curcumin and 1-1-diphenyl-2-picrylhydrazyl

On the basis of our previous work, a novel series of (4-(1,2,4-oxadiazol-5-yl)phenyl)-2-aminoacetamide derivatives were synthesized and evaluated as multifunctional ligands for the treatment of Alzheimer's disease (AD). Biological evaluations indicated that the derivatives can be used as anti-AD drugs that have multifunctional properties, inhibit the activity of butyrylcholinesterase (BuChE), inhibit neuroinflammation, have neuroprotective properties, and inhibit the self-aggregation of Aβ. Compound f9 showed good potency in BuChE inhibition (IC

Topics: Acetamides; Alzheimer Disease; Amyloid beta-Peptides; Antioxidants; Biphenyl Compounds; Butyrylcholinesterase; Cholinesterase Inhibitors; Dose-Response Relationship, Drug; Drug Design; Humans; Molecular Structure; Neuroprotective Agents; Oxadiazoles; Picrates; Protein Aggregates; Structure-Activity Relationship

Topics: Animals; Antineoplastic Agents; Antioxidants; Biphenyl Compounds; Cell Proliferation; Cell Survival; Cells, Cultured; Curcumin; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Lung Neoplasms; Mitogen-Activated Protein Kinases; Molecular Structure; Neoplasms, Experimental; NF-kappa B; Picrates; STAT3 Transcription Factor; Structure-Activity Relationship; Triazoles; Zebrafish

By coupling a quaternary pyridinium compound and curcumin (CM), a new antimicrobial agent called CP was obtained. The poor water-solubility was the most important limiting factor in the use of CM and CP. To address this problem, a hydrophilic hyperbranched polyglycerol (PG) was synthesized and reacted with CM and CP via Schiff base reaction to form two new macromolecules. Due to the presence of polymer, the solubility and stability of CM and CP increased significantly in aqueous media. Since the new macromolecules were including the hydrophilic polymeric and curcumin hydrophobic units, they self-assembled into spherical nanostructures, which were characterized by Field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) images. The synthetic nanostructures exhibited a controlled release of curcumin unit in the acidic environment. In vitro experiments showed that the new macromolecules are potent antibacterial and antioxidant agents.

Topics: Anti-Bacterial Agents; Antioxidants; Biphenyl Compounds; Curcumin; Dose-Response Relationship, Drug; Drug Design; Escherichia coli; Glycerol; Microbial Sensitivity Tests; Molecular Structure; Nanostructures; Picrates; Polymers; Solubility; Staphylococcus aureus; Structure-Activity Relationship

Hypoxia is a condition that gradually leads to ischemic damages in organs which is marked by poor tissue perfusion. Depending on the severity of the condition, revascularisation therapies are needed for reducing the risk of organ dysfunction. This study was aimed at developing an injectable nanocurcumin and arginine incorporated chitosan hydrogel (nC/R) that can prevent hypoxia induced endothelial damage. The prepared hydrogel has shear thinning, stable and injectable nature. The (nC and nC/R) hydrogels showed significant antioxidant activity and biodegradation in vitro. The release of curucmin and arginine from the nC/R was found to be higher at acidic pH, which predominates in an ischemic site. To mimic low oxygen environment, an in vitro hypoxic endothelial dysfunction model was developed which showed decreased expressions of phosphorylated eNOS (serine 1177) when compared to the cells cultured in normoxic condition. In vitro tube formation assay demonstrated the protective effect of nC/R towards hypoxia induced reduction of tube width. The nC/R hydrogel was found to enhance phosphorylation of eNOS at serine 1177 site in cultured endothelial cells subjected to hypoxia. Therefore, nC/R hydrogel could effectively deliver both curcumin and arginine and therapeutically reduce the effect of hypoxia induced endothelial dysfunction.

Topics: Antioxidants; Arginine; Biphenyl Compounds; Cell Hypoxia; Chitosan; Curcumin; Human Umbilical Vein Endothelial Cells; Humans; Hydrogels; Nanoparticles; Neovascularization, Physiologic; Nitric Oxide Synthase Type III; Phosphorylation; Picrates; Spectroscopy, Fourier Transform Infrared; Superoxides

Strong hydrophilicity of polysaccharide and physicochemical instability of peptides limit application of polysaccharide-peptide mixtures in food industry. In this study, a natural resource platform of polysaccharide-peptide conjugates was constructed through Maillard reaction from chitosan and casein hydrophobic peptide. By choosing the molecular weight and deacetylation degree of chitosan and other reaction parameters, the conjugated chitosan-peptides possess extensive HLB values from 6 to 14 were obtained with grafting degree of 3.10%-15.08%. The conjugates have gained dramatically improved emulsifying ability, and endowed the emulsion higher antioxidant capacity than the peptide, chitosan and the mixture of peptide-chitosan has. Emulsions prepared with all conjugates exhibited long-term stability and strengthened tolerance towards temperature and electrolyte stimuli. This stable emulsion system also provided an effective encapsulation, protection and controlled release of curcumin, which may provide a method for transfer polysaccharides to stable emulsifiers with broader HLB values and application.

Topics: Antioxidants; Biphenyl Compounds; Chitosan; Curcumin; Drug Compounding; Drug Delivery Systems; Drug Liberation; Drug Stability; Electrolytes; Emulsifying Agents; Emulsions; Free Radical Scavengers; Free Radicals; Hydrophobic and Hydrophilic Interactions; Lipids; Maillard Reaction; Oxidants; Peptides; Picrates; Polysaccharides; Solubility; Surface Properties; Surface-Active Agents; Temperature; Viscosity

Topics: Adsorption; Animals; Antioxidants; Biphenyl Compounds; Buffers; Cattle; Curcumin; Flavonoids; Free Radical Scavengers; Hydrogen-Ion Concentration; Inhibitory Concentration 50; Ions; Metals; Phenols; Picrates; Polysaccharides; Protective Agents; Serum Albumin, Bovine; Solutions; Spectroscopy, Fourier Transform Infrared; Ultraviolet Rays

A pectin/chitosan matrix-loaded curcumin film (PCCF) with a deep eutectic solvent (DES) as the solvent and plasticizer was prepared in this study. Different quantities of curcumin (identified as PCCF-0, PCCF-1, PCCF-2. PCCF-3) were loaded on the pectin/chitosan film in order to evaluate their effects on the film properties. Results showed that curcumin could interact with the pectin/chitosan matrix and form a complex three-dimensional network structure. PCCF could promote the thickness, tensile strength, thermal properties, antioxidant and antiseptic capacities, but deteriorate the light transmission and elongation at the same time. The addition of curcumin would change the color of the film, without significantly affecting the moisture content. The tensile strength of PCCF-3 reached the maximum value of 3.75 MPa, while the elongation decreased to 10%. Meanwhile, the water-resistance properties of PCCF-3 were significantly promoted by 8.6% compared with that of PCCF-0. Furthermore, PCCF showed remarkable sustained antioxidant activities in a dose-dependent manner. PCCF-3 could inhibit DPPH and ABTS free radicals by 58.66% and 29.07%, respectively. It also showed antiseptic capacity on fresh pork during storage. Therefore, curcumin addition could improve the barrier, mechanical, antioxidant and antiseptic properties of the polysaccharide-based film and PCCF has the potential to be used as a new kind of food packaging material in the food industry.

Topics: Anti-Infective Agents, Local; Antioxidants; Benzothiazoles; Biocompatible Materials; Biphenyl Compounds; Chitosan; Curcumin; Food; Free Radical Scavengers; Humidity; Pectins; Picrates; Solubility; Spectroscopy, Fourier Transform Infrared; Sulfonic Acids; Water; X-Ray Diffraction

A new 3,4-difluorobenzylidene analog of curcumin, CDF, was recently reported, which demonstrated significantly enhanced bioavailability and in vivo anticancer activity compared with curcumin. For highlighting the antiparasitic behavior of CDF, we tested this compound together with its new O-methylated analog MeCDF against Leishmania major and Toxoplasma gondii parasites. Both CDF and MeCDF were tested in vitro against L. major and T. gondii. In addition, the in vitro cytotoxicity against Vero cells and macrophages was determined and selectivity indices were calculated. The DPPH radical scavenging activity assay was carried out in order to determine the antioxidant activity of the test compounds. Both compounds showed high activities against both parasite forms with EC

Topics: Animals; Antioxidants; Antiparasitic Agents; Biphenyl Compounds; Chlorocebus aethiops; Curcumin; Diarylheptanoids; Female; Halogenation; Leishmania major; Macrophages; Mice; Mice, Inbred BALB C; Molecular Structure; Parasitic Sensitivity Tests; Picrates; Toxoplasma; Vero Cells

Curcuminoids are the main bioactive components of the well-known Asian spice and traditional medicine turmeric. Curcuminoids have poor chemical stability and bioavailability; in vivo they are rapidly metabolized to a set of bioreduced derivatives and/or glucuronide and sulfate conjugates. The reduced curcuminoid metabolites were also reported to exert various bioactivities in vitro and in vivo. In this work, we aimed to perform a comparative evaluation of curcuminoids and their hydrogenated metabolites from a medicinal chemistry point of view, by determining a set of key pharmacokinetic parameters and evaluating antioxidant potential in relation to such properties.Reduced metabolites were prepared from curcumin and demethoxycurcumin through continuous-flow hydrogenation. As selected pharmacokinetic parameters, kinetic solubility, chemical stability, metabolic stability in human liver microsomes, and parallel artificial membrane permeability assay (PAMPA)-based gastrointestinal and blood-brain barrier permeability were determined. Experimentally determined logP for hydrocurcumins in octanol-water and toluene-water systems provided valuable data on the tendency for intramolecular hydrogen bonding by these compounds. Drug likeness of the compounds were further evaluated by a in silico calculations. Antioxidant properties in diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and oxygen radical absorbance capacity (ORAC) assays were comparatively evaluated through the determination of ligand lipophilic efficiency (LLE). Our results showed dramatically increased water solubility and chemical stability for the reduced metabolites as compared to their corresponding parent compound. Hexahydrocurcumin was found the best candidate for drug development based on a complex pharmacokinetical comparison and high LLE values for its antioxidant properties. Development of tetrahydrocurcumin and tetrahydro-demethoxycurcumin would be limited by their very poor metabolic stability, therefore such an effort would rely on formulations bypassing first-pass metabolism.

Topics: Antioxidants; Biological Availability; Biphenyl Compounds; Cell Membrane Permeability; Chemistry, Pharmaceutical; Curcuma; Curcumin; Diarylheptanoids; Glucuronides; Humans; Hydrogenation; Microsomes, Liver; Picrates; Solubility

An electrospun nanofiber based on pullulan/chitin nanofibers (PCN) containing curcumin (CR) and anthocyanins (ATH) was developed using an electrospinning technique for active-intelligent food packaging. The results of scanning electron microscopy and attenuated total reflection Fourier transform infrared spectroscopy indicated that CR and ATH were successfully immobilized on the film-forming substrate based on PCN. The physical and chemical properties of nanofibers with no colorant, a single colorant, and double colorants were compared. The nanofiber containing ATH and CR (PCN/CR/ATH) had stronger antioxidant and antimicrobial activities than those of nanofibers containing CR (PCN/CR) or ATH (PCN/ATH). With respect to pH sensitivity, the color of the PCN/CR nanofibers did not change obviously, but the color of the PCN/ATH and PCN/CR/ATH nanofibers changed significantly with the change in pH. Furthermore, the PCN/CR/ATH nanofibers clearly changed color with the progressive spoilage of Plectorhynchus cinctus at room temperature. Therefore, the electrospun PCN/CR/ATH nanofiber have great application potential in active-intelligent food packaging.

Topics: Animals; Anthocyanins; Anti-Bacterial Agents; Antioxidants; Biphenyl Compounds; Chitin; Color; Curcumin; Escherichia coli; Fishes; Food Microbiology; Food Packaging; Food Preservation; Food Quality; Glucans; Hydrogen-Ion Concentration; Nanofibers; Nanotechnology; Picrates; Seafood; Smart Materials; Staphylococcus aureus

Neurodegenerative diseases have a complex nature which highlights the need for multitarget ligands to address the complementary pathways involved in these diseases. Over the last decade, many innovative curcumin-based compounds have been designed and synthesized, searching for new derivatives having anti-amyloidogenic, inhibitory of tau formation, as well as anti-neuroinflammation, antioxidative, and AChE inhibitory activities. Regarding our experience studying 3-substituted coumarins with interesting properties for neurodegenerative diseases, our aim was to synthesize a new series of curcumin-coumarin hybrid analogues and evaluate their activity. Most of the 3-(7-phenyl-3,5-dioxohepta-1,6-dien-1-yl)coumarin derivatives

Topics: Acetylcholinesterase; Animals; Antioxidants; Biphenyl Compounds; Butyrylcholinesterase; Cell Line, Tumor; Cell Survival; Cholinesterase Inhibitors; Coumarins; Curcumin; GPI-Linked Proteins; Humans; Hydrogen Peroxide; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Motor Cortex; Nanoparticles; Neurons; Neuroprotective Agents; Picrates; Primary Cell Culture; Rats; Structure-Activity Relationship

The intelligent pH indicator films were prepared by incorporating curcumin-loaded Pickering emulsion with corn starch (CS) and polyvinyl alcohol (PVA) matrix. The mechanical properties, barrier properties and functional characteristics of the films were studied and the films were applied to monitor fish freshness. Fourier transform infrared (FTIR) spectroscopy and Scanning electron microscopy (SEM) showed that Pickering emulsion can form hydrogen bonds with CS and PVA. The antioxidant activity of the films was detected, which showed that Pickering emulsion could reduce the decomposition of curcumin during the process of preparation and storage. Bactericidal tests showed that the films can inhibit the growth of S. aureus, B. subtilis, and E. coli, and the effect of the films on Gram-positive (G

Topics: Animals; Anti-Bacterial Agents; Antioxidants; Biphenyl Compounds; Color; Curcumin; Emulsions; Fishes; Food Packaging; Free Radical Scavengers; Hydrogen-Ion Concentration; Microbial Sensitivity Tests; Picrates; Polyvinyl Alcohol; Spectroscopy, Fourier Transform Infrared; Starch; Tensile Strength

Curcumin extracted from the rhizome of

Topics: Anti-Infective Agents; Biofilms; Biphenyl Compounds; Cell Death; Cell Line; Curcumin; Drug Liberation; Free Radical Scavengers; Humans; Infections; Kinetics; Microbial Sensitivity Tests; Nanofibers; Picrates; Polyesters; Quorum Sensing; Thermogravimetry; Tissue Engineering

The functional gelatin/curcumin composite film was prepared using an emulsifier, sodium dodecyl sulfate (SDS). The composite films were characterized using field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FTIR). The FE-SEM test results showed that curcumin was evenly distributed in the gelatin polymer matrix to form a flexible composite film with a smooth surface. The addition of 1.5 % of curcumin improved the UV blocking effect by more than 99 % at a loss of 5.7 % of transparency compared to neat gelatin films. The addition of curcumin (up to 1 wt%) significantly improved mechanical and water vapor barrier properties. Also, the gelatin/curcumin composite films exhibited remarkable antimicrobial activity against foodborne pathogenic bacteria, E. coli and L. monocytogenes, and showed strong antioxidant activity comparable to ascorbic acid. Antibacterial and antioxidant gelatin/curcumin composite films with improved UV protection, water vapor barrier and mechanical properties have high potential in active food packaging applications.

Topics: Anti-Bacterial Agents; Antioxidants; Benzothiazoles; Biphenyl Compounds; Curcumin; Escherichia coli; Food Packaging; Gelatin; Listeria monocytogenes; Microbial Sensitivity Tests; Particle Size; Picrates; Sodium Dodecyl Sulfate; Stress, Mechanical; Sulfonic Acids; Surface Properties

In this manuscript, lysozyme/κ-carrageenan (LYS-CRG) complexes were prepared and used to encapsulate curcumin. The LYS-CRG complexes demonstrate good encapsulation of curcumin (CUR), and the encapsulation efficiency (EE) and loading capacity (LC) reach 96.2% and 2.31%, respectively. The encapsulated CUR has high antioxidant activity, while the thermal stability and photostability of CUR are also increased. The LYS-CRG complexes could effectively improve the storage stability of CUR and increase its retention rate. In simulated gastric fluid, only 17.91% CUR in the CUR-LYS-CRG complex nanoparticles is released in 3 h, while in the simulated intestinal fluid, the CUR release rate quickly reaches 62.56% in 1.5 h. The release rate tends to be stable within 1.5 h to 3 h and the final release rate reaches 67.23%, suggesting that the formation of CUR-LYS-CRG complex nanoparticles does not affect CUR release in the simulated intestinal fluid.

Topics: Biphenyl Compounds; Carrageenan; Curcumin; Delayed-Action Preparations; Drug Carriers; Drug Liberation; Emulsions; Free Radical Scavengers; Light; Muramidase; Nanoparticles; Nephelometry and Turbidimetry; Particle Size; Picrates

The aim of this study was to develop a zein/potato starch (PS) film based on chitosan nanoparticles incorporated with curcumin (CCN). The CCN film was characterized for encapsulation efficiency, particle size, zeta potential, polydispersity index (PDI), relative release, and DPPH radical scavenging test. Our results showed that the CCN encapsulated effectively curcumin (CUR) (84.8% ± 1.1%) and presented with high oxidation resistance and relative release efficiency. The CCN/zein/PS composite films were round, smooth, and compact. We measured and compared the mechanical properties, oxygen permeability (OP), water vapor permeability (WVP), relative release efficiency, and DPPH radical scavenging properties of the composite films of different mass ratios. We observed that the composite film had good mechanical and barrier properties. Further, we evaluated the preservative efficacy of the composite film on Schizothorax prenati fillets by measuring pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid-reactive substances (TBARS), hardness, microbial counts, organoleptic characteristics, and other fillet quality parameters. The CCN/zein/PS composite film delayed physicochemical changes in the Schizothorax prenati fillets and prolonged their shelf life by up to 15 days. In conclusion, our work shows that CCN/zein/PS composite film holds promise as a potential bioactive packaging material for Schizothorax prenati fillets.

Topics: Animals; Biphenyl Compounds; Chitosan; Cryopreservation; Curcumin; Cyprinidae; Food Packaging; Food Preservation; Food Preservatives; Hydrogen-Ion Concentration; Manufactured Materials; Materials Testing; Meat; Microscopy, Electron; Nanoparticles; Oxygen; Particle Size; Permeability; Picrates; Solanum tuberosum; Starch; Static Electricity; Steam; Tensile Strength; Zein

We previously reported the antifungal, antioxidant, and vasodilator effects of Ryudai gold (RD) and isolated some potentially active compounds. Here, we aimed to identify other active compounds present in RD and investigate their pharmacological effects, in terms of antioxidant, and inhibitory activities against skin disease-related enzymes, pancreatic α-amylase, and lipase enzymes. The methanol extract of RD rhizomes was subjected to repeated fractionation by silica gel column, Toyopearl HW-40F column, and high-performance liquid chromatography to obtain a pure compound. The isolated compound was characterized by analyzing its spectroscopic data, particularly nuclear magnetic resonance spectra. Inhibitory activities against α-amylase, pancreatic lipase, elastase, collagenase, xanthine oxidase, and tyrosinase were evaluated to investigate its potential antidiabetic, antiobesity, and enzyme inhibitory effects. Antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl-scavenging, reducing power, and 2-deoxyribose degradation assays. The purified compound was recognized as 4-methylene-8-hydroxybisabola-2,10-diene-9-one, a new compound. The content of this compound was 0.068 μmol/g or 0.016 mg/g of dry RG powder. Our results suggested that 4-methylene-8-hydroxybisabola-2,10-diene-9-one exhibited antidiabetic, antiobesity, enzyme inhibitory, and antioxidant activities by inhibiting their respective enzymes activity. 4-methylene-8-hydroxybisabola-2,10-diene-9-one could be a promising candidate therapeutic agent or a lead compound for the development of new synthetic drugs.

Topics: Animals; Anti-Obesity Agents; Antioxidants; Biphenyl Compounds; Cell Line, Tumor; Cell Survival; Curcuma; Enzyme Inhibitors; Hypoglycemic Agents; Mice; Monophenol Monooxygenase; Picrates; Plant Extracts; Rhizome

This investigation was designed to evaluate the chemical composition, antioxidant, anti-inflammatory, genotoxicity, and antimicrobial activities of Curcuma caesia Roxb rhizome essential oil.. Gas Chromatography/Mass Spectroscopy (GC/MS) analysis was performed to determine the chemical composition, standard antioxidative test DPPH assay, reducing power assay, in vitro antiinflammatory activity (egg albumin denaturation, protease inhibitory assay) by using standard methods. Similarly, antimicrobial activity was tested using the disc diffusion method, minimum inhibitory concentration ability (MIC); while to test genotoxicity, Allium cepa assay was used.. GC/MS analysis revealed eucalyptol (28.55%), epicurzerenone (19.62%), and camphor (21.73%) as the major components of C. caesia rhizome essential oil. Potent antioxidant (IC50= 48.08±0.003 μg/mL), anti-inflammatory (IC50= 121.7±0.0013 μg/mL), and antimicrobial activities of the essential oil were recorded better than the standard drugs Fluconazole for fungus and Ciprofloxacin for bacteria. The essential oil also possessed a strong antibacterial effect against two tested bacterial strains B. subtilis and B. cereus with 7.5 μg/mL MIC value, while for fungal strains the essential oil was most effective against S. cereviaceae with an MIC value of 2.5 μg/mL. All the data were recorded in triplicates. Allium cepa assay revealed minor genotoxicity with mitotic index, MI= 27.70%; chromosome aberration, A= 1.1% of C. caesia rhizome essential oil.. C. caesia rhizome essential oil possesses potent antioxidant, anti-inflammatory, and antimicrobial properties with negligible genotoxicity. Hence, the present study is highly significant for the utilization of rhizome of C. caesia, a high-value ethnopharmacological plant for advanced R & D and commercial application.

Topics: Anti-Infective Agents; Anti-Inflammatory Agents; Antioxidants; Bacillus subtilis; Biphenyl Compounds; Chromosome Aberrations; Curcuma; Egg Proteins; Gas Chromatography-Mass Spectrometry; India; Microbial Sensitivity Tests; Oils, Volatile; Onions; Picrates; Protein Denaturation; Rhizome; Saccharomyces cerevisiae

In this study, we fabricated a series of novel sodium alginate/ZnO hydrogel beads to optimize the release profile of curcumin (Cur) and to avoid the burst release associated with pure hydrogels, which were used to mitigate the weaknesses of Cur, such as rapid physiological clearance and sensitivity to ultraviolet (UV) light and alkaline solutions. The results show that the composite hydrogel beads exhibit good pH sensitivity and controlled-release capacity, which could prolong the residence time of Cur in the gastrointestinal tract. After exposure to UV irradiation for 6 h, the 1,1-Diphenyl-2-picrylhydrazyl (DPPH) scavenging capacity of Cur-loaded hydrogel beads was decreased by only 13.70%, whereas that of pure Cur decreased by 62.04% under the same conditions; therefore, the encapsulated Cur showed a higher antioxidant activity. The composite hydrogel beads protected the Cur from light degradation and can therefore prolong the antioxidant activity of Cur. These results are beneficial for the design of delivery systems to entrap and control the release of unstable drugs.

Topics: Alginates; Antioxidants; Biphenyl Compounds; Curcumin; Drug Carriers; Drug Liberation; Gastrointestinal Tract; Hydrogels; Hydrogen-Ion Concentration; Microspheres; Picrates; Zinc Oxide

Pelleted preparations were formulated from sacran (Sac), an anionic, sulfated, carboxyl-containing polysaccharide, which is extracted from the Japanese indigenous cyanobacterium Aphanothece sacrum, and surface-deacetylated chitin nanofibers (SDACNF). The use of this material as an extended-release excipient for tetrahydrocurcumin (THC), a model drug that is used to treat wounds via its radical scavenging ability was examined. The THC used in the study was complexed with 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), which increases its water solubility. The radical scavenging activity of the THC/HP-β-CD complex (molar ratio of 1:1) was significantly higher than the values for SDACNF or Sac alone. The rate of release of THC from the Sac/SDACNF pellets containing the THC/HP-β-CD complex decreased with increasing Sac content in the pellet, suggesting that Sac/SDACNF (1:1) and Sac alone pellets function as extended-release excipients for THC. The findings reported here indicate that this can be attributed to the ability of the Sac component to retain fluids, thus extending the effects of the drug. In view of the above experimental outcomes, i.e. wound healing efficacy, fluid absorption, retention and the extended drug release of the system indicates that this preparation, in the appropriate ratios, has the potential for use as a controlled-release drug in wound healing.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Animals; Biphenyl Compounds; Chitin; Curcumin; Cyanobacteria; Delayed-Action Preparations; Drug Liberation; Excipients; Free Radical Scavengers; Kinetics; Male; Nanofibers; Picrates; Polysaccharides; Rats; Rats, Sprague-Dawley; Solubility; Surgical Wound; Water; Wound Healing

In this work, in order to enhance the stability, bioavailability and antioxidant activity of insoluble antioxidants used into juice, yoghourt and nutritional supplements, the oligo-hyalurosomes nano-delivery system (CRHs) based on oligo-hyaluronic acid -curcumin (oHC) polymer loaded curcumin(Cur) and resveratrol (Res) was fabricated with new nanotechnolgy. The rosy biodegradable amphiphilic oHC polymer was successfully synthesized and used to fabricate the hyalurosomes containing both Cur and Res, called CRHs. The CRHs can spontaneously self-assemble into nano-sized spherical shape of average particle size 134.5±5.1nm and Zeta potential -29.4±1.2 at pH 7.4 PBS conditions. In vitro gastrointestinal release test showed a perfect stability and outstanding sustained release character. Moreover, compared to the single formulations and liposomes, CRHs showed a dose-dependent manner with a higher radical scavenging activity. Therefore, the novel CRHs nano-food manifested the hopeful properties for the new effective gastrointestinal formulation and promising new nano-food delivery system in the use of juice, yoghourt and nutritional supplements.

Topics: Antioxidants; Biphenyl Compounds; Curcumin; Dietary Supplements; Drug Compounding; Drug Liberation; Food; Free Radical Scavengers; Hyaluronic Acid; Nanoparticles; Particle Size; Picrates; Polymers; Proton Magnetic Resonance Spectroscopy; Resveratrol; Stilbenes

A series of fourteen new asymmetrical 1,3-diketone derivatives have been synthesized and evaluated in the ABTS, FRAP and DPPH assays as a new chemotype with antioxidant and drug-like properties. All the compounds displayed low cytotoxicity in comparison to curcumin against the human neuroblastoma SH-SY5Y cell line. Among them, (3

Topics: Antioxidants; Apoptosis; Benzothiazoles; Biphenyl Compounds; Cell Line, Tumor; Cell Survival; Curcumin; Humans; Hydrogen Peroxide; Inhibitory Concentration 50; Iron Chelating Agents; Ketones; Membrane Potential, Mitochondrial; Neurons; Neuroprotective Agents; Oxidative Stress; Picrates; Quinones; Structure-Activity Relationship; Sulfonic Acids

The objective of this work was to investigate and profoundly characterize low-energy nanoemulsions as multifunctional carriers, with slight reference to dermal administration. An evidence-based approach was offered for deepening the knowledge on their formation via spontaneous emulsification. Curcumin, a compound of natural origin, potentially powerful therapeutic, was chosen as a model API. Due to curcumin's demanding properties (instability, poor solubility, low permeability), its potentials remain unreached. Low-energy nanoemulsions were considered carriers capable of overcoming imposed obstacles. Formulation consisting of Polysorbate 80 and soybean lecithin as stabilizers (9:1, 10%), medium-chain triglycerides as the oil phase (10%) and ultrapure water was selected for curcumin incorporation in 3 different concentrations (1, 2 and 3 mg/mL). Physicochemical stability was demonstrated during 3 months of monitoring (mean droplet size: 111.3-146.8 nm; PDI < 0.2; pH: 4.73-5.73). Curcumin's release from developed vehicles followed Higuchi's kinetics. DPPH (IC50 = 0.1187 mg/mL) and FRAP (1.19 ± 0.02 mmol/g) assays confirmed that curcumin acts as a potent antioxidant through different mechanisms, with no alterations after incorporation in the formulation. High biocompatibility in line with antigenotoxic activity of curcumin-loaded formulations (protective and reparative) was estimated through Comet assay. A multidisciplinary approach is needed to fully characterize developed systems, directing them to more concrete application possibilities.

Topics: Adult; Antioxidants; Biphenyl Compounds; Comet Assay; Curcumin; Drug Administration Routes; Drug Liberation; Emulsions; Female; Humans; Nanoparticles; Picrates

This study evaluated the efficacy of various organic solvents (80% acetone, 80% ethanol, 80% methanol) and distilled water for extracting antioxidant phenolic compounds from turmeric, curry leaf, torch ginger and lemon grass extracts. They were analyzed regarding the total phenol and flavonoid contents, antioxidant activity and concentration of some phenolic compounds. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and the ferric reducing antioxidant power (FRAP) assay. Quantification of phenolic compounds was carried out using high-performance liquid chromatography (HPLC). All the extracts possessed antioxidant activity, however, the different solvents showed different efficiencies in the extraction of phenolic compounds. Turmeric showed the highest DPPH values (67.83-13.78%) and FRAP (84.9-2.3 mg quercetin/g freeze-dried crude extract), followed by curry leaf, torch ginger and lemon grass. While 80% acetone was shown to be the most efficient solvent for the extraction of total phenolic compounds from turmeric, torch ginger and lemon grass (221.68, 98.10 and 28.19 mg GA/g freeze dried crude extract, respectively), for the recovery of phenolic compounds from curry leaf (92.23 mg GA/g freeze-dried crude extract), 80% ethanol was the most appropriate solvent. Results of HPLC revealed that the amount of phenolic compounds varied depending on the types of solvents used.

Topics: Acetone; Antioxidants; Biphenyl Compounds; Chromatography, High Pressure Liquid; Curcuma; Cymbopogon; Ethanol; Flavonoids; Liquid-Liquid Extraction; Methanol; Phenols; Picrates; Plant Extracts; Solvents; Spices; Zingiber officinale

Curcumin (CUR) has properties that can be useful for the treatment of Alzheimer's disease. Such properties are the inhibition of amyloid-β-protein (Aβ) aggregation, Aβ-induced inflammation, and activities of β-secretase and acetylcholinesterase. However, previous studies have revealed that CUR exhibited low bioavailability and difficulties in reaching the brain.. To overcome such drawbacks, this study aims at developing nasal lipid nanocarriers loaded with CUR to effectively target the brain.. The lipid nanocarriers (NE) were prepared using the hot solvent diffusion associated with the phase inversion temperature methods. Physico-chemical and morphological characterizations and in vitro drug release of the nanocarriers were carried out. The CUR permeation/retention was analyzed in Franz-type diffusion cell using porcine nasal mucosa. Confocal laser scan and histopathological studies were also performed.. The results showed that the NE sizes ranged between 18 nm and 44 nm with negative zeta potential. The CUR content ranged from 0.24 to 1.50 mg/mL with an encapsulation efficiency of 99%. The profiles of CUR release indicated a biphasic kinetics. CUR-NE permeation across the porcine nasal mucosa was higher when compared to free CUR. These results have also been validated through an analysis on a confocal microscopy. In addition, no toxicity on the nasal mucosa has been observed in a histopathological analysis.. These results suggest that it is possible to develop NEs with a high content of CUR and small particle size. Such an encapsulation increases the potential of CUR permeation across the porcine nasal mucosa.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Biphenyl Compounds; Curcumin; Dose-Response Relationship, Drug; Drug Compounding; Lipids; Microscopy, Confocal; Microscopy, Electron, Transmission; Nanoparticles; Nasal Mucosa; Picrates; Polyethylene Glycols; Swine; Time Factors

Topics: alpha-Tocopherol; Biphenyl Compounds; Cell Survival; Chemical Phenomena; Curcumin; Drug Carriers; Drug Liberation; Emulsions; Hep G2 Cells; Humans; Hydrogen-Ion Concentration; Isothiocyanates; Nanostructures; Oils; Osmolar Concentration; Particle Size; Picrates; Polysorbates; Sonication; Stearates; Surface-Active Agents; Water

Core-shell nanofibers were designed via electrospinning using inclusion complex (IC) of model hydrophobic drug (curcumin, CUR) with cyclodextrin (CD) in the core and polymer (polylactic acid, PLA) in the shell (cCUR/HPβCD-IC-sPLA-NF). CD-IC of CUR and HPβCD was formed at 1:2 molar ratio. The successful formation of core-shell nanofibers was revealed by TEM and CLSM images. cCUR/HPβCD-IC-sPLA-NF released CUR slowly but much more in total than PLA-CUR-NF at pH 1 and pH 7.4 due to the restriction of CUR in the core of nanofibers and solubility improvement shown in phase solubility diagram, respectively. Improved antioxidant activity of cCUR/HPβCD-IC-sPLA-NF in methanol:water (1:1) is related with the solubility enhancement achieved in water based system. The slow reaction of cCUR/HPβCD-IC-sPLA-NF in methanol is associated with the shell inhibiting the quick release of CUR. On the other hand, cCUR/HPβCD-IC-sPLA-NF exhibited slightly higher rate of antioxidant activity than PLA-CUR-NF in methanol:water (1:1) owing to the enhanced solubility. To conclude, slow release of CUR was achieved by core-shell nanofiber structure and inclusion complexation of CUR with HPβCD provides high solubility. Briefly, electrospinning of core-shell nanofibers with CD-IC core could offer slow release of drugs as well as solubility enhancement for hydrophobic drugs.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Antioxidants; beta-Cyclodextrins; Biphenyl Compounds; Curcumin; Drug Carriers; Drug Liberation; Nanofibers; Picrates; Polyesters; Solubility; Water

New fourteen 3,4-dihydropyrimidine derivatives/analogues of curcumin (2a-2n) were designed, synthesized and biologically evaluated for their cytotoxicity and antioxidant activity. Cytotoxicity effect has been evaluated against three cell lines HeLa, HCT-116 and QG-56 by MTT assay method. From SAR study, it has been revealed that particularly, compound 2e and 2j (IC50 value 12.5 μM) have shown better cytotoxicity effect against three cell lines. According to results of SAR study, it was found that 3,4-dihydropyrimidines of curcumin, 2c, 2d, 2j and 2n exhibited better antioxidant activity than curcumin. A correlation of structure and activities relationship of these compounds with respect to drug score profiles and other physico-chemical properties of drugs are described and verified experimentally. Therefore, we conclude that physico-chemical analyses may prove structural features of curcumin analogues with their promising combined cytotoxicity/antioxidant activity and it is also concluded from virtual and practical screening that the compounds were varied to possess a broad range of lipophilic character, revealed by Log P values.

Topics: Antineoplastic Agents; Biphenyl Compounds; Cell Line, Tumor; Curcumin; Drug Design; Free Radical Scavengers; Humans; Nitric Oxide; Picrates; Structure-Activity Relationship

Curcumin nanoemulsions (Cur-NEs) were developed with various surfactant concentrations by using high pressure homogenization and finally applied to the commercial milk system. Characterization of Cur-NEs was performed by measuring the droplet size and polydispersity index value at different Tween 20 concentrations. The morphology of the Cur-NEs was observed by confocal laser scanning microscopy and transmission electron microscopy. Antioxidant activity and in vitro digestion ability were tested using 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, pH-stat method, and thiobarbituric acid reactive substances assays. Cur-NEs were found to be physically stable for 1 mo at room temperature. The surfactant concentration affects particle formation and droplet size. The mean droplet size decreased from 122 to 90 nm when surfactant concentration increased 3 times. Cur-NEs had shown an effective oxygen scavenging activity. Cur-NEs-fortified milk showed significantly lower lipid oxidation than control (unfortified) milk and milk containing curcumin-free nanoemulsions. These properties make Cur-NEs suitable systems for the beverage industry.

Topics: Animals; Antioxidants; Biological Availability; Biphenyl Compounds; Curcuma; Curcumin; Diet; Digestion; Emulsions; Food Handling; Humans; In Vitro Techniques; Lipid Peroxidation; Milk; Oxidation-Reduction; Picrates; Polysorbates; Reactive Oxygen Species; Solubility; Surface-Active Agents

Eight phenolic compounds including: p-coumaric acid, vanillic acid, caffeic acid, chlorogenic acid, trolox, quercetin, curcumin, and resveratrol were treated with riboflavin (RF) photosensitization and in vitro antioxidant capacities of the mixtures were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2' azino bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. Mixtures containing p-coumaric acid and vanillic acid under RF photosensitization showed increases in ferric ion reducing ability and radical scavenging activity of DPPH, whereas mixtures of other compounds had decreases in both radical scavenging ability and ferric reducing antioxidant power. Hydroxycoumaric acid and conjugated hydroxycoumaric and coumaric acids were tentatively identified from RF photosensitized p-coumaric acid, whereas dimmers of vanillic acid were tentatively identified from RF photosensitized vanillic acid. RF photosensitization may be a useful method to enhance antioxidant properties like ferric ion reducing abilities of some selected phenolic compounds.

Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; Caffeic Acids; Chlorogenic Acid; Chromans; Coumaric Acids; Curcumin; Light; Molecular Structure; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Propionates; Quercetin; Resveratrol; Riboflavin; Stilbenes; Sulfonic Acids; Vanillic Acid

The role of vesicle-to-micelle transition has been investigated in the interactions of phospholipid vesicles, phospholipid/sodium cholate (NaC) mixed vesicles, and phospholipid/NaC mixed micelles with curcumin in aqueous solution. The addition of NaC causes phospholipid vesicles to transit into phospholipid/NaC mixed vesicles and phospholipid/NaC mixed micelles. Turbidity measurement reveals that the presence of curcumin increases the NaC concentration for the solubilization of phospholipid vesicles, which indicates that the bound curcumin tends to suppress the vesicle-to-micelle transition. The pyrene polarity index and curcumin fluorescence anisotropy measurements suggest that phospholipid/NaC mixed micelles have a more compact structure than that of phospholipid vesicles and phospholipid/NaC mixed vesicles. Curcumin associated with phospholipid vesicles, phospholipid/NaC mixed vesicles, and phospholipid/NaC mixed micelles often results in higher intensities of absorption and fluorescence than those of free curcumin. However, phospholipid/NaC mixed vesicles lead to the highest values of absorption and fluorescence intensities, binding constant, and radical-scavenging capacity with curcumin. The different structures in the phospholipid bilayer of phospholipid/NaC mixed vesicles and the hydrophobic part of phospholipid/NaC mixed micelles where curcumin located are discussed to explain the interaction behaviors of phospholipid/NaC mixed systems with curcumin.

Topics: Biphenyl Compounds; Curcumin; Drug Carriers; Fluorescence Polarization; Free Radical Scavengers; Hydrogen Bonding; Hydrophobic and Hydrophilic Interactions; Micelles; Microscopy, Electron, Transmission; Phospholipids; Picrates; Sodium Cholate; Spectrophotometry; Water

'Ubtan' is a traditional herbal formulation in the Indian system of medicine being used in India and its subcontinent for a long time. Several commercial skin care formulations are marketed throughout this region as the name of Ubtan. Therefore, it is worthwhile to evaluate Ubtan in respect of its efficacy as skin care formulation.. The present study was designed for the preparation of Ubtan and standardization through the chromatographic techniques by using suitable phyto-markers. Further, its antioxidant, sun protection factor (SPF) and anti-tyrosinase potential have been explored.. Four in-house formulations (UF-1, UF-2, UF-3 and UF-4) were prepared by mixing a varied quantity of each powdered plants, i.e. turmeric (Curcuma longa L.), Chickpea (Cicer arietinum L.) and sandalwood (Santalum album L.). Optimization of the formulations was made by evaluating its biological activity through in vitro assay. Evaluation of physicochemical properties of the optimized formulation (UF-1) has been carried out by analysis of pH, flow properties and stability. Moreover, RP-HPLC (reverse phase - high performance liquid chromatography) and HPTLC (high performance thin layer chromatography) standardization of UF-1 was performed for its quantitative and qualitative analysis.. Ubtan formulations (UF-1to UF-4) showed free radical scavenging and ferric reducing potential. It may be due to its high phenolic and flavonoid content. Statistically, significant Pearson's correlation (r) was confirmed the positive correlation between phenolic content and SPF of the formulations. The tyrosinase inhibition study indicated that the formulations showed both diphenolase and monophenolase inhibitory activity. Among four formulations, UF-1 showed notable biological activity (p<0.05). The content of curcumin and ascorbic acid was found to be 1.6% and 2.1% w/w respectively in UF-1 through RP-HPLC estimation. Physiochemical properties of the UF-1 exhibited good flow rate and aqueous solubility. From the stability studies, it can be anticipated that the UF-1 was stable at 40°C for longer periods. Microbial load count and heavy metal content (lead-Pb, arsenic-As, mercury-Hg and cadmium-Cd) of the formulation was also within the permissible limit of a pharmacopeial standard.. This scientific exploration helps to set the quality and safety standard of traditional cosmetic formulation, Ubtan and its further use as an herbal skin care product.

Topics: Antioxidants; Ascorbic Acid; Bacterial Load; Biphenyl Compounds; Chromatography, High Pressure Liquid; Chromatography, Reverse-Phase; Chromatography, Thin Layer; Cicer; Consumer Product Safety; Curcuma; Curcumin; Dermatologic Agents; Dose-Response Relationship, Drug; Drug Compounding; Drug Contamination; Drug Stability; Enzyme Inhibitors; Ferricyanides; Hydrogen-Ion Concentration; India; Medicine, Traditional; Metals, Heavy; Monophenol Monooxygenase; Oxidation-Reduction; Phytotherapy; Picrates; Plant Preparations; Plants, Medicinal; Powders; Quality Control; Rheology; Risk Assessment; Santalum; Skin Care; Solubility; Spectrophotometry, Atomic; Spectrophotometry, Ultraviolet; Sunscreening Agents

The decay of dpph˙ in absolute ethanol at 25 °C and in the presence of curcumin (1), 4-methylcurcumin (3), 4,4-dimethylcurcumin (4) or curcumin 4'-methyl ether (5) follows bi-exponential kinetics. These unusual reaction kinetics are compatible with a two-step process in which an intermediate accumulates in a reversible first step followed by an irreversible process. As in other similar cases (Foti et al., Org. Lett., 2011, 13, 4826-4829), we have hypothesised that the intermediate is a π-stacked complex, formed between one curcumin anion (in the case of 1, 3 and 5 the enolate anion) and the picryl moiety of dpph˙, in which an intra-complex electron transfer from the (enolate) anion takes place. By comparing the kinetics of curcumin 4',4''-dimethyl ether (2) (no phenolic OH), (5) (one phenolic OH) and (1) (two phenolic OHs), we have deduced that the electron transfer process must be accompanied by a simultaneous proton transfer from the phenolic OHs to the bulk solvent (separated coupled proton-electron transfer). The rate constants kα for the forward reaction of 2, 5 and 1 with dpph˙ are in fact ∼0, 7.5 × 10(3) and 1.8 × 10(4) M(-1) s(-1), respectively, in a clear dependence on the number of phenolic OHs.

Topics: Biphenyl Compounds; Curcumin; Electron Transport; Electrons; Kinetics; Molecular Structure; Oxidation-Reduction; Picrates; Protons; Solvents

The influence of solid state fermentation (SSF) by Trichoderma spp. on the solubility, total phenolic content, antioxidant, and antibacterial activities of turmeric was determined and compared with unfermented turmeric. The solubility of turmeric was monitored by increase in its phenolic content. The total phenolic content of turmeric extracted by 80% methanol and water after SSF by six species of Trichoderma spp. increased significantly from 2.5 to 11.3-23.3 and from 0.5 to 13.5-20.4 GAE/g DW, respectively. The antioxidant activities of fermented turmeric were enhanced using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS), and ferric ion-reducing antioxidant power (FRAP) assays. The antibacterial activity of fermented turmeric against human-pathogenic bacteria Escherichia coli, Streptococcus agalactiae, Staphylococcus aureus, Entreococcus faecalis, Methicillin-Resistant S. aureus, Klebsiella pneumonia, and Pseudomonas aeruginosae showed a broad spectrum inhibitory effect. In conclusion, the results indicated the potentials of using fermented turmeric as natural antioxidant and antimicrobial material for food applications.

Topics: Anti-Bacterial Agents; Antioxidants; Biphenyl Compounds; Curcuma; Enterococcus faecalis; Escherichia coli; Fermentation; Klebsiella pneumoniae; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Phenols; Picrates; Plant Extracts; Pseudomonas aeruginosa; Solubility; Staphylococcus aureus; Streptococcus agalactiae; Trichoderma

Extraction parameters, chemical fingerprint, and the single compounds' activity levels were considered for the selection of active botanicals. For an initial survey, the total bioactivity (i.e., total reducing capacity, total flavonoids contents and free radical scavenging capacity) of 21 aqueous and 21 ethanolic plant extracts was investigated. Ethanolic extracts showed a higher yield and were further analyzed by HPTLC in detail to obtain fingerprints of single flavonoids and further bioactive components. Exemplarily shown for turmeric (Curcuma longa) and milk thistle (Silybum marianum), effect-directed analysis (EDA) was performed using three selected (bio)assays, the Aliivibrio fischeri bioassay, the Bacillus subtilis bioassay and the 2,2-diphenyl-1-picrylhydrazyl (DPPH*) assay. As a proof of principle, the bioactive components found in the extracts were confirmed by HPTLC-MS. Bioassays in combination with planar chromatography directly linked to the known, single effective compounds like curcumin and silibinin. However, also some unknown bioactive components were discovered and exemplarily characterized, which demonstrated the strength of this kind of EDA. HPTLC-UV/Vis/FLD-EDA-MS could become a useful tool for selection of active botanicals and for the activity profiling of the active ingredients therein. The flexibility in effect-directed detections allows a comprehensive survey of effective ingredients in samples. This streamlined methodology comprised a non-targeted, effect-directed screening first, followed by a highly targeted characterization of the discovered bioactive compounds. HPTLC-EDA-MS can also be recommended for bioactivity profiling of food on the food intake side, as not only effective phytochemicals, but also unknown bioactive degradation products during food processing or contamination products or residues or metabolites can be detected. Thus, an efficient survey on potential food intake effects on wellness could be obtained. Having performed both, sum parameter assays and HPTLC analysis, a comparison of both approaches was made and discussed.

Topics: Aliivibrio fischeri; Anti-Bacterial Agents; Antioxidants; Bacillus subtilis; Biological Assay; Biphenyl Compounds; Chromatography, Thin Layer; Curcuma; Curcumin; Picrates; Plant Extracts; Silybin; Silybum marianum; Silymarin; Spectrometry, Mass, Electrospray Ionization

The quantitative free radical scavenging capacity of curcumin and its demethoxy derivatives (demethoxycurcumin (Dmc) and bisdemethoxycurcumin (Bdmc)) and hydrogenated derivatives (tetrahydrocurcumin (THC), hexahydrocurcumin (HHC) and octahydrocurcumin (OHC)) towards 1,1-diphenyl-2-picryl hydrazyl (DPPH), nitric oxide radical (NO), hydroxyl radical (HO(·)) and superoxide anion radical (O2(·)) were investigated by electron paramagnetic resonance (EPR) spectroscopy. One mole of the hydrogenated derivatives scavenged about 4 mol of the DPPH radical, while curcumin and Dmc scavenged about 3 mol of the DPPH radical. Curcumin and THC showed moderate scavenging activity towards NO, yielding 200 mmol of NO scavenged per 1 mol of the scavenger. In contrast, curcumin and its derivatives showed very low scavenging activity towards HO(·) and O2(·), yielding approximately only 3-12 mmol scavenged per 1 mol of the tested compounds. Our results suggest that curcumin and its derivatives principally act as chain breaking antioxidants rather than as direct free radical scavengers. Furthermore, we showed that the ortho-methoxyphenolic group and the heptadione linkage of these molecules greatly contributed to their DPPH and NO scavenging activity.

Topics: Biphenyl Compounds; Curcumin; Electron Spin Resonance Spectroscopy; Free Radical Scavengers; Hydroxyl Radical; Nitric Oxide; Picrates; Superoxides

A solvent-free, mechanochemical method for the synthesis of curcumin (1) derived 3,5-bis(styryl)pyrazoles and 3,5-bis(styryl)isoxazole (2a-g) at room temperature, with very short reaction time, is reported. Such earlier structural modifications of curcumin, at its β-diketone unit by transforming it into an isosteric pyrazole or isoxazole unit, required prolonged heating. The evaluation of the antioxidant activity of these compounds, based on DPPH, FRAP, and β-carotene bleaching assays, showed that several of these azoles are better antioxidants than curcumin, with the isoxazole derivative 2g being overall the best. Typically, the inhibition of 2,2-diphenyl-1-picrylhydrazyl (10(-2) mmol), expressed as EC50 values, by curcumin (1), 3,5-bis(4-hydroxy-3-methoxystyryl)pyrazole (2a), and 3,5-bis(4-hydroxy-3-methoxystyryl)isoxazole (2g) are 40 ± 0.06, 14 ± 0.18, and 8 ± 0.11 μmol, respectively. Moreover, the reported method is useful in accessing 3,5-bis(4-hydroxy-3-methoxystyryl)-1-phenylpyrazole (2b), which is important in studies related to neuroprotection and Alzheimer's disease, and 2a and 2g, which are inhibitors of protein kinases involved in neuronal excitotoxicity.

Topics: Antioxidants; Azoles; beta Carotene; Biphenyl Compounds; Curcumin; Dose-Response Relationship, Drug; Drug Design; Fluorescence Recovery After Photobleaching; Molecular Structure; Picrates; Structure-Activity Relationship

The phytochemical composition and antioxidant capacities of 6 new NRCRI turmeric (Curcuma longa L.) accessions (39, 35, 60, 30, 50 and 41) were determined using standard techniques. The moisture contents of the tumeric samples ranged from 15.75 to 47.80% and the curcumin contents of the turmeric samples fell within the range of curcumin obtained from turmeric in other countries of the world. Furthermore, the turmeric accessions contained considerable amounts of antioxidants (measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and reducing power assays), alkaloids, flavonoids, anthocyanins, and phenolics. There was significant correlation between the anthocyanin contents of the tumeric accessions versus their alkaloid (0.744) and flavonoid contents (0.986) suggesting an additive effect between the anthocyanins and alkaloids in turmeric; significant correlation between the inhibition of the turmeric accessions on DPPH radical versus their flavonoid (0.892) and anthocyanin (0.949) contents and significant correlation between the reducing power of the turmeric accessions versus their flavonoid (0.973) and anthocyanin (0.974) contents suggesting that anthocyanins as flavonoids largely contribute to the antioxidant activities of turmeric. The positive regression recorded between inhibition of DPPH radical by the turmeric accessions and quercetin versus reducing power (R2 = 0.852) suggest that any of these methods could be used to assess the antioxidant activities of tumeric. Finally, the study indicated the potentials of the turmeric accessions especially accessions 30 and 50 as promising sources of antioxidants.

Topics: Alkaloids; Anthocyanins; Antioxidants; Biphenyl Compounds; Curcuma; Flavonoids; Humans; Oxidation-Reduction; Patents as Topic; Phenols; Picrates; Plant Extracts; Polyphenols

The objective of this study was to evaluate the effect of Curcuma longa powder and ascorbic acid on some quality traits of rabbit burgers. The burgers (burgers control with no additives; burgers with 3.5 g of turmeric powder/100g meat; burgers with 0.1g of ascorbic acid/100g meat) were analyzed at Days 0 and 7 for pH, color, drip loss, cooking loss, fatty acid profile, TBARS, antioxidant capacity (ABTS, DPPH and FRAP) and microbial growth. The addition of turmeric powder modified the meat color, produced an antioxidant capacity similar to ascorbic acid and determined a lower cooking loss than other formulations. Turmeric powder might be considered as a useful natural antioxidant, increasing the quality and extending the shelf life of rabbit burgers.

Topics: Animals; Antioxidants; Ascorbic Acid; Benzothiazoles; Biphenyl Compounds; Color; Cooking; Curcuma; Food Handling; Food Preservation; Food Preservatives; Food Storage; Humans; Meat; Meat Products; Picrates; Plant Extracts; Powders; Rabbits; Sulfonic Acids; Thiobarbituric Acid Reactive Substances; Water

Potency of medicinal plant is related to microorganisms lived in the plant tissue. Those microorganisms are known as endophytic microbes that live and form colonies in the plant tissue without harming its host. Each plant may contains several endophytic microbes that produce biological compounds or secondary metabolites due to co-evolution or genetic transfer from the host plant to endophytic microbes. Endophytic fungi research done for turmeric plant (Curcuma longa L.) gave 44 isolated fungi as results. Those 44 fungi isolated were fermented in Potato Dextrose Broth (PDB) media, filtered, extracted with ethylacetate and then were analyzed by Thin Layer Chromatography (TLC) method and tested for their antioxidant activity by radical scavenging method. The antioxidant activity of the ethylacetate filtrate extracts either from Sukabumi or Cibinong were higher than the biomass extracts. There were 6 fungi that showed antioxidant activities over 65%, i.e., with code name K.Cl.Sb.R9 (93.58%), K.Cl.Sb.A11 (81.49%), KCl.Sb.B1 (78.81%), KCl.Sb.R11 (71.67%) and K.Cl.Sb.A12 (67.76%) from Sukabumi and K.Cl.Cb.U1 (69.27%) from Cibinong. These results showed that bioproduction by endophytic microbes can gave potential antioxidant compounds.

Topics: Antioxidants; Biphenyl Compounds; Curcuma; Endophytes; Fungi; Indonesia; Phytotherapy; Picrates; Plants, Medicinal

The cellular and molecular mechanisms by which neuroinflammatory pathways respond to and propagate the reactive tissue response to intracortical microelectrodes remain active areas of research. We previously demonstrated that both the mechanical mismatch between rigid implants and the much softer brain tissue, as well as oxidative stress, contribute to the neurodegenerative reactive tissue response to intracortical implants. In this study, we utilize physiologically responsive, mechanically adaptive polymer implants based on poly(vinyl alcohol) (PVA), with the capability to also locally administer the antioxidant curcumin. The goal of this study is to investigate if the combination of two independently effective mechanisms - softening of the implant and antioxidant release - leads to synergistic effects in vivo. Over the first 4weeks of the implantation, curcumin-releasing, mechanically adaptive implants were associated with higher neuron survival and a more stable blood-brain barrier at the implant-tissue interface than the neat PVA controls. 12weeks post-implantation, the benefits of the curcumin release were lost, and both sets of compliant materials (with and without curcumin) had no statistically significant differences in neuronal density distribution profiles. Overall, however, the curcumin-releasing softening polymer implants cause minimal implant-mediated neuroinflammation, and embody the new concept of localized drug delivery from mechanically adaptive intracortical implants.

Topics: Animals; Antioxidants; Astrocytes; Biphenyl Compounds; Blood-Brain Barrier; Cell Count; Cellulose; Cerebral Cortex; Cicatrix; Curcumin; Glial Fibrillary Acidic Protein; HMGB1 Protein; Immunoglobulin G; Implants, Experimental; Inflammation; Macrophages; Male; Microglia; Nanoparticles; Neuraminidase; Neurons; Permeability; Picrates; Polyvinyl Alcohol; Rats; Urochordata; Wound Healing

The antioxidative properties of a novel curcumin analogue (2E,6E)-2,6-bis(3,5-dimethoxybenzylidene)cyclohexanone (MCH) were assessed by several in vitro models, including superoxide anion, hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and PC12 cell protection from H2O2 damage. MCH displayed superior O2•- quenching abilities compared to curcumin and vitamin C. In vitro stability of MCH was also improved compared with curcumin. Exposure of PC12 cells to 150 µM H2O2 caused a decrease of antioxidant enzyme activities, glutathione (GSH) loss, an increase in malondialdehyde (MDA) level, and leakage of lactate dehydrogenase (LDH), cell apoptosis and reduction in cell viability. Pretreatment of the cells with MCH at 0.63-5.00 µM before H2O2 exposure significantly attenuated those changes in a dose-dependent manner. MCH enhanced cellular expression of transcription factor NF-E2-related factor 2 (Nrf2) at the transcriptional level. Moreover, MCH could mitigate intracellular accumulation of reactive oxygen species (ROS), the loss of mitochondrial membrane potential (MMP), and the increase of cleaved caspase-3 activity induced by H2O2. These results show that MCH protects PC12 cells from H2O2 injury by modulating endogenous antioxidant enzymes, scavenging ROS, activating the Nrf2 cytoprotective pathway and prevention of apoptosis.

Topics: Animals; Antioxidants; Apoptosis; Biphenyl Compounds; Blotting, Western; Caspase 3; Catalase; Cell Survival; Curcumin; Cyclohexanones; Free Radical Scavengers; Gene Expression; Glutathione; Hydrogen Peroxide; Hydroxyl Radical; Lipid Peroxidation; Molecular Structure; NF-E2-Related Factor 2; Oxidants; PC12 Cells; Picrates; Plant Preparations; Protective Agents; Rats; Reverse Transcriptase Polymerase Chain Reaction; Superoxide Dismutase; Superoxides

The purpose of this work was to synthesize a series of symmetrical analogs (CA2-CA7) of curcumin and determine their efficacy as antioxidant and anticancer agents in vitro. The six analogs were successfully synthesized and characterized, one of which, CA6, had not been previously reported in the literature. With the exception of CA2, the analogs had lower predicted aqueous solubilities and higher partition coefficients than curcumin. Two analogs, CA2 and CA3, had lower potencies as anticancer agents compared with curcumin, while CA6 had a slightly higher IC50 value. Two different trends in the antioxidant capabilities of curcumin and its analogs were determined when assessed in vitro or in cell culture. The in vitro DPPH assay clearly showed curcumin as the strongest antioxidant as compared with the analogs when tested at the same concentration or at their IC50 value. The cell culture-based reactive oxygen species/reactive nitrogen species assay indicated that CA3 and CA6 were equal to curcumin in their free radical scavenging ability at the same concentration, but when curcumin and its analogs were tested at their respective IC50 values, CA4 and CA5 showed excellent antioxidant capacities. These results indicate that in cell culture, the ability of these analogs to produce antioxidant effects may be tied to their downstream effects.

Topics: Antineoplastic Agents, Phytogenic; Antioxidants; Biphenyl Compounds; Cell Line, Tumor; Cell Survival; Curcumin; Free Radicals; Humans; Molecular Structure; Picrates; Solubility; Structure-Activity Relationship

An attempt to augment the antioxidant ability of curcumin, a natural phenolic compound via encapsulation in nontoxic nanoemulsions, has been made. Ethanol and glycerol catalyzed curcumin encapsulated nanoemulsions using cottonseed oil with mild cationic, anionic and nonionic surfactants have been prepared. The prepared bionanoemulsions were found to possess characteristic particle diameter between 100 and 900nm. The curcumin encased bionanoemulsions have been further screened for antioxidant efficacy with free radical 2, 2-diphenyl-1-picrylhydrazyl that enabled a radical scavenging activity of more than 90% as compared to pure curcumin. Alongside, the reduced surface tension and increased viscosity of curcumin encapsulated bionanoemulsions within 38.37-52.85mN/m and 0.7947-1.042mPa-s have quantitatively verified curcumin dispersion and interaction within the continuous medium, enabled via thermodynamic shift.

Topics: Antioxidants; Biphenyl Compounds; Curcumin; Emulsions; Free Radical Scavengers; Nanocapsules; Picrates; Surface Tension; Thermodynamics; Viscosity

Curcumin, a polyphenolic compound extracted from Curcuma longa, has several pharmacological activities such as anticancer, anti-inflammatory, and antioxidant effects. The purpose of this study was to investigate the protective effects of curcumin and THERACURMIN, a highly bioavailable curcumin, against sodium nitroprusside (SNP)-induced oxidative damage in primary striatal cell culture. THERACURMIN as well as curcumin significantly prevented SNP-induced cytotoxicity. To elucidate the cytoprotective effects of curcumin and THERACURMIN, we measured the intracellular glutathione level in striatal cells. Curcumin and THERACURMIN significantly elevated the glutathione level, which was decreased by treatment with SNP. Moreover, curcumin showed potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging ability. Finally, a ferrozine assay showed that curcumin (10-100 µg/mL) has potent Fe(2+)-chelating ability. These results suggest that curcumin and THERACURMIN exert potent protective effects against SNP-induced cytotoxicity by free radical-scavenging and iron-chelating activities.

Topics: Animals; Biphenyl Compounds; Cells, Cultured; Corpus Striatum; Curcumin; Free Radical Scavengers; Glutathione; Iron; L-Lactate Dehydrogenase; Neuroprotective Agents; Nitroprusside; Oxidative Stress; Picrates; Rats; Rats, Wistar

Human mesenchymal stem cells (hMSCs) are considered a highly promising candidate cell type for cell-based tissue engineering and regeneration because of their self-renewal and multi-lineage differentiation characteristics. Increased levels of reactive oxygen/nitrogen species (ROS/RNS) are associated with tissue injury and inflammation, impact a number of cellular processes, including cell adhesion, migration, and proliferation, and have been linked to cellular senescence in MSCs, potentially compromising their activities. Naturally occurring polyphenolic compounds (polyphenols), epigallocatechin-3-gallate (EGCG), and curcumin, block ROS/RNS and are potent inflammation-modulating agents. However, their potential protective effects against oxidative stress in hMSCs have not been examined. In this study, we carried out a systematic analysis of the effects of polyphenols on hMSCs in their response to oxidative stress in the form of treatment with H(2)O(2) and S-nitroso-N-acetylpenicillamine (SNAP), respectively. Parameters measured included colony forming activity, apoptosis, and the levels of antioxidant enzymes and free reactive species. We found that polyphenols reversed H(2)O(2) -induced loss of colony forming activity in hMSCs. In a dose-dependent manner, polyphenols inhibited increased levels of ROS and NO, produced by H(2)O(2) or SNAP, respectively, in MSCs. Notably, polyphenols rapidly and almost completely blocked H(2)O(2) -induced ROS in the absence of significant direct effect on H(2)O(2) itself. Polyphenols also protected the antioxidant enzymes and reduced apoptotic cell death caused by H(2)O(2) exposure. Taken together, these findings demonstrate that EGCG and curcumin are capable of suppressing inducible oxidative stress in hMSCs, and suggest a possible new approach to maintain MSC viability and potency for clinical application.

Topics: Biphenyl Compounds; Bone Marrow Cells; Catalase; Catechin; Colony-Forming Units Assay; Curcumin; Cytoprotection; Cytosol; DNA Damage; Female; Glutathione Peroxidase; Humans; Hydrogen Peroxide; Intracellular Space; Male; Mesenchymal Stem Cells; Middle Aged; Nitric Oxide; Oxidative Stress; Picrates; Polyphenols; S-Nitroso-N-Acetylpenicillamine

Leaf extracts of C. vamana, endemic to Kerala state in India, were found to inhibit cell cycle progression in synchronous cultures of P. polycephalum in a concentration and phase-specific manner. Crude alkaloid extract (CAE) elicited maximum cell cycle delays in comparison to soxhletted chloroform, acetone and aqueous extracts. Total alkaloid content of CAE was found to be 64.9 mg/g. CAE showed lowest DPPH radical scavenging activity. Other extracts with higher free radical scavenging activity exhibited lesser cell cycle inhibiting potential. Upto 21% decrease in nuclear DNA was observed in CAE treated samples. However, genotoxicity as evidenced by comet assay was not observed. The extracts were also found to be non-toxic to human RBCs at the highest concentration tested (750 microg/mL). CAE treatment completely suppressed a 63 kDa polypeptide with a concomitant, but weak induction of a 60 kDa polypeptide suggesting that these may be cell cycle related. CAE was found to possess potent antiproliferative activity against PBLs. The study clearly demonstrates the cell cycle inhibitory activity of C. vamana leaf extracts, with CAE being the most potent of them.

Topics: Alkaloids; Biphenyl Compounds; Cell Cycle; Cell Nucleus; Cell Proliferation; Comet Assay; Curcuma; DNA Damage; Dose-Response Relationship, Drug; Flow Cytometry; Free Radicals; Humans; Lymphocytes; Mitosis; Models, Biological; Physarum polycephalum; Picrates; Plant Extracts; Plant Leaves

The capability of crude ethanolic extracts of certain medicinal plants like Phytolacca decandra, Gelsemium sempervirens, Hydrastis canadensis and Thuja occidentalis used as homeopathic mother tinctures in precipitating silver nanoparticles from aqueous solution of silver nitrate has been explored. Nanoparticles thus precipitated were characterized by spectroscopic, dynamic light scattering, X-ray diffraction, atomic force and transmission electron microscopic analyses. The drug-DNA interactions of silver nanoparticles were analyzed from data of circular dichroism spectroscopy and melting temperature profiles using calf thymus DNA (CT-DNA) as target. Biological activities of silver nanoparticles of different origin were then tested to evaluate their effective anti-proliferative and anti-bacterial properties, if any, by exposing them to A375 skin melanoma cells and to Escherichia coli C, respectively. Silver nanoparticles showed differences in their level of anti-cancer and anti-bacterial potentials. The nanoparticles of different origin interacted differently with CT-DNA, showing differences in their binding capacities. Particle size differences of the nanoparticles could be attributed for causing differences in their cellular entry and biological action. The ethanolic extracts of these plants had not been tested earlier for their possible efficacies in synthesizing nanoparticles from silver nitrate solution that had beneficial biological action, opening up a possibility of having therapeutic values in the management of diseases including cancer.

Topics: Biphenyl Compounds; Cell Division; Cell Line; Cell Survival; Circular Dichroism; Comet Assay; DNA Damage; Escherichia coli; Ethanol; Free Radical Scavengers; G2 Phase; Gelsemium; Hydrastis; Microbial Sensitivity Tests; Microscopy, Atomic Force; Microscopy, Electron, Transmission; Nanoparticles; Particle Size; Phytolacca dodecandra; Picrates; Real-Time Polymerase Chain Reaction; Silver; Silver Nitrate; Solvents; Spectrophotometry, Ultraviolet; Thuja; X-Ray Diffraction

Twenty-nine phenolic compounds were isolated from the root bark of fresh (Yunnan) ginger and their structures fully characterized. Selected compounds were divided into structural categories and twelve compounds subjected to in-vitro assays including DPPH radical scavenging, xanthine-oxidase inhibition, monoamine oxidase inhibition, rat-brain homogenate lipid peroxidation, and rat pheochromocytoma PC12 cell and primary liver cell viability to determine their antioxidant and cytoprotective properties. Isolated compounds were also tested against nine human tumor cell lines to characterize anticancer potency. Several diarylheptanoids and epoxidic diarylheptanoids were effective DPPH radical scavengers and moderately effective at inhibiting xanthine oxidase. An enone-dione analog of 6-shogaol (compound 2) was isolated and identified to be most effective at protecting PC12 cells from H₂O₂-induced damage. Almost all tested compounds inhibited lipid peroxidation. Three compounds, 6-shogaol, 10-gingerol and an enone-diarylheptanoid analog of curcumin (compound 6) were identified to be cytotoxic in cell lines tested, with KB and HL60 cells most susceptible to 6-shogaol and the curcumin analog with IC₅₀<10 μM. QSAR analysis revealed cytotoxicity was related to compound lipophilicity and chemical reactivity. In conclusion, we observed distinct compounds in fresh ginger to have biological activities relevant in diseases associated with reactive oxygen species.

Topics: Animals; Antineoplastic Agents, Phytogenic; Antioxidants; Biphenyl Compounds; Catechols; Curcumin; Cytoprotection; Fatty Alcohols; HL-60 Cells; Humans; Hydrogen Peroxide; Hydrophobic and Hydrophilic Interactions; KB Cells; Lipid Peroxidation; Neoplasms; PC12 Cells; Phenols; Phytotherapy; Picrates; Plant Bark; Plant Extracts; Plant Roots; Rats; Xanthine Oxidase; Zingiber officinale

This paper investigated the influences of temperature on the stability and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of curcumin encapsulated in liposome at pH 7.0. Liposomal curcumin showed higher stability and DPPH scavenging activity than free curcumin at 25°C. When temperature increased from 25 to 80°C, liposomal curcumin degraded more pronouncedly above the phase transition temperature (T(m)=45.7°C) of liposome than lower temperatures, suggesting a weaker curcumin protection from the liquid crystalline phase of phospholipid bilayer than that from the gel phase. Moreover, the presence of remarkable "jump" increases around T(m) in the values of observed pseudo-first-order rate constant and the percent of DPPH scavenging activity of liposomal curcumin indicated that the liquid crystalline phase of phospholipid bilayer is more beneficial for curcumin to reduce DPPH. This study reveals that changing the microstructure of encapsulation carrier may effectively control the properties of phytochemicals like curcumin.

Topics: Biphenyl Compounds; Curcumin; Drug Compounding; Free Radical Scavengers; Hydrogen-Ion Concentration; Liposomes; Picrates; Temperature

The biological importance of antioxidants influenced to synthesize some curcumin-related compounds as potential antioxidants. Accordingly, a series of 2,4-diaryl-3-azabicyco[3.3.1]nonan-9-ones were synthesized with polyphenolic and/or polymethoxyphenyl groups by modified Mannich condensations. The yield was significantly improved using BF(3)·SiO(2) as heterogeneous catalyst under mild conditions. Stereochemistry of all the synthesized compounds was established as twin-chair with an equatorial disposition of the aryl groups, through their NMR and XRD interpretations. The ABNs 8 (curcumin analog) and 10 (bis-demethoxycurcumin analog) showed an effective profile over curcumin, α-tocopherol, and vitamin C by chemical methods. Further, the efficiency of one of the active molecules, ABN 10, was demonstrated by its intracellular ROS inhibition activity on RAW 264.7 macrophage cells by FACS analysis in dose-dependent manner.

Topics: alpha-Tocopherol; Animals; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Boranes; Catalysis; Cell Line; Curcumin; Macrophages; Mannich Bases; Mice; Models, Molecular; Oxidation-Reduction; Picrates; Reactive Oxygen Species; Silicon Dioxide

A wide range of proteinaceous inhibitors are present in plants to protect themselves from hydrolytic enzymes. In this study, turmerin, a water-soluble peptide in turmeric rhizomes, was evaluated for its inhibitory potential against glucosidase and its antioxidant (AO) capacity. Turmerin inhibited α-amylase and α-glucosidase activities with IC₅₀ values 31 and 192 µg mL⁻¹, respectively. Under the experimental conditions, those values for a standard glucosidase inhibitor, acarbose, were 81 and 296 µg mL⁻¹, respectively. The AO capacity of turmerin was evaluated using in vitro assay systems. Turmerin showed good DPPH (IC₅₀ = 29 µg mL⁻¹) and superoxide (IC₅₀ = 48 µg mL⁻¹) and moderate ABTS (IC₅₀ = 83 µg mL⁻¹) radical scavenging and Fe(II) chelation (IC₅₀ = 101 µg mL⁻¹) capacities. The inhibitory potential showed by turmerin against enzymes linked to type 2 diabetes, as well as its moderate AO capacity, could rationalise the traditional usage of turmeric rhizome preparations against diabetes.

Topics: alpha-Amylases; alpha-Glucosidases; Antioxidants; Benzothiazoles; Biphenyl Compounds; Curcuma; Hypoglycemic Agents; Intercellular Signaling Peptides and Proteins; Peptides; Picrates; Sulfonic Acids; Superoxides

Free radicals and reactive oxygen species are compounds usually present in healthy organisms as natural products of many metabolic pathways, and they are important in cell signaling and homeostasis. As a source of reactive oxygen species one can mention phagocytic cells and enzymes such as xanthine oxidase. Sometimes the level of reactive oxygen species strongly increases. This may lead to damage of very important cell structures such as nucleic acids, proteins or lipids. In this situation one should provide the organism with powerful antioxidants as a medicine or in the diet. A rich source of strong antioxidants such as phenolic compounds is plant raw materials, which are the subject of our study.. Antiradical potential of extracts was measured with DPPH radical (2,2-diphenyl-1-picrylhydrazyl) and was expressed as the number of units per mg of extracts (TAU(515/mg)) and per g of raw material (TAU(515/g)). The amount of phenolic compounds was determined colorimetrically using Folin-Ciocalteu phenol reagent (3H₂O • P₂O5 • 13WO₃ • 5MoO₃ • 10H₂O).. The strongest antiradical activity was noted for extracts obtained from Cinnamomi cortex; the number of antiradical units per mg of extract (TAU(515/mg)) was 10.31±1.052. The lowest antiradical features were exhibited by extract from Zingiberis rhizoma (0.28±0.174) and extract from Cichorii radix (0.38±0.669). The highest amount of phenolic compounds was measured for extracts from Bistortae rhizoma, with a value (in percentage) of 78.6±13.5. The correlation coefficient between the number of antiradical units in extracts and amount of phenolic compounds in these extracts was 0.7273. When the number of antiradical units was calculated per g of raw material (TAU(515/g)) the strongest antiradical properties were noted for Bistortae rhizoma (1406±274.9), the weakest for Cichorii radix (122±158.3).

Topics: Biphenyl Compounds; Cichorium intybus; Cinnamomum zeylanicum; Curcuma; Drugs, Chinese Herbal; Free Radical Scavengers; Free Radicals; Models, Chemical; Phenols; Picrates; Plant Bark; Plant Extracts; Plant Roots; Polygonum; Reactive Oxygen Species; Rhizome; Tannins; Zingiberales

Three curcumin analogues viz., bisdemethoxy curcumin, monodemethoxy curcumin, and dimethoxycurcumin that differ at the phenolic substitution were synthesized. These compounds have been subjected for free radical reactions with DPPH radicals, superoxide radicals (O(2)(•-)), singlet oxygen ((1)O(2)) and peroxyl radicals (CCl(3)O(2)(•)) and the bimolecular rate constants were determined. The DPPH radical reactions were followed by stopped-flow spectrometer, (1)O(2) reactions by transient luminescence spectrometer, and CCl(3)O(2)(•) reactions using pulse radiolysis technique. The rate constants indicate that the presence of o-methoxy phenolic OH increases its reactivity with DPPH and CCl(3)O(2)(•), while for molecules lacking phenolic OH, this reaction is very sluggish. Reaction of O(2)(•-) and (1)O(2) with curcumin analogues takes place preferably at β-diketone moiety. The studies thus suggested that both phenolic OH and the β-diketone moiety of curcumin are involved in neutralizing the free radicals and their relative scavenging ability depends on the nature of the free radicals.

Topics: Biphenyl Compounds; Carbon Tetrachloride; Curcumin; Diarylheptanoids; Free Radical Scavengers; Free Radicals; Hydroxyl Radical; Peroxides; Picrates; Pulse Radiolysis; Reactive Oxygen Species; Singlet Oxygen; Spectrum Analysis; Structure-Activity Relationship; Superoxides

A series of polyphenolic curcumin analogs were synthesized and their inhibitory effects on mushroom tyrosinase and the inhibition of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical formation were evaluated. The results indictated that the analogs possessing m-diphenols and o-diphenols exhibited more potent inhibitory activity on tyrosinase than reference compound rojic acid, and that the analogs with o-diphenols exhibited more potent inhibitory activity of DPPH free-radical formation than reference compound vitamin C. The inhibition kinetics, analyzed by Lineweaver-Burk plots, revealed that compounds B(2) and C(2) bearing o-diphenols were non-competitive inhibitors, while compounds B(11) and C(11) bearing m-diphenols were competitive inhibitors. In particular, representative compounds C(2) and B(11) showed no side effects at a dose of 2,000 mg/kg in a preliminary evaluation of acute toxicity in mice. These results suggest that such polyphenolic curcumin analogs might serve as lead compounds for further design of new potential tyrosinase inhibitors.

Topics: Agaricales; Animals; Biphenyl Compounds; Catalytic Domain; Curcumin; Drug Discovery; Enzyme Inhibitors; Female; Free Radical Scavengers; Hydroxides; Inhibitory Concentration 50; Male; Mice; Models, Molecular; Monophenol Monooxygenase; Picrates; Polyphenols

Our previous report has showed that demethoxycurcumin (DMC), a natural derivative of curcumin (Cur), exhibited stronger inhibitory activity on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production compared with Cur in lipopolysaccharide (LPS) activated rat primary microglia. In the present study, the effect and possible mechanism of DMC on the production of pro-inflammatory mediators in LPS-activated N9 microglial cells were further investigated. The results showed that DMC significantly suppressed the NO production induced by LPS in N9 microglial cells through inhibiting the protein and mRNA expression of inducible NO synthase (iNOS). DMC also decreased LPS-induced TNF-alpha and IL-1beta expression at both transcriptional and protein level in a concentration-dependent manner. Further studies revealed that DMC blocked IkappaBalpha phosphorylation and degradation, inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs). Moreover, the level of intracellular reactive oxygen species (iROS) was significantly increased by LPS, which is mainly mediated by the up-regulated expression of gp91phox, the catalytic subunit of nicotinamide adenine dinucleotide phosphate reduced (NADPH) oxidase. Both DMC and Cur could markedly decrease iROS production and the expression of NADPH oxidase induced by LPS, with more potent inhibitory activity of DMC. In summary, these data suggest that DMC exerts its in vitro anti-inflammatory effect in LPS-activated N9 microglial cells by blocking nuclear factor-kappaB (NF-kappaB) and MAPKs activation, which may be partly due to its potent down-regulation of the NADPH-derived iROS production.

Topics: Animals; Anti-Inflammatory Agents; Biphenyl Compounds; Blotting, Western; Cell Survival; Curcumin; Diarylheptanoids; Down-Regulation; Inflammation; Interleukin-1beta; Lipopolysaccharides; Macrophage Activation; Mice; Microglia; Mitogen-Activated Protein Kinases; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Nitrites; Picrates; Reactive Oxygen Species; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Tumor Necrosis Factor-alpha

A facile, convenient and high yielding synthesis of a combinatorial library of 3-alkanoyl/aroyl/heteroaroyl-2H-chromene-2-thiones has been developed by the condensation of easily accessible beta-oxodithioesters and salicylaldehyde/substituted 2-hydroxybenzaldehydes under solvent-free conditions. The assessment of radical scavenging capacity of the compounds towards the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) was measured and these compounds were found to scavenge DPPH free radical efficiently. Five selected compounds were able to protect curcumin from the attack of sulfur free radical generated by radiolysis of glutathione (GSH). The newly synthesized compounds exhibited profound antioxidant activities. Five of them rendered comparatively high antioxidant capacity.

Topics: Biphenyl Compounds; Curcumin; Free Radical Scavengers; Picrates; Sulfur; Thiones

Research on curcumin (polyphenol derived from the rhizome of herb Curcuma longa) has occupied a unique niche owing to its distinctive properties, unique molecular architecture and multi-potent efficacies, particularly in the bio-medical domain with recent interest in material science. In the present study, conjugation of curcumin onto biocompatible poly(ethylene glycol)--templated magnetic iron oxide nanoparticles (MNP) (2-5 nm), prepared through a simple wet chemical route is reported along with modulation of the activity of the partners. Statistical optimization, using response surface methodology, of sonication parameters (8 min, 0.4 cycle and 60% amplitude) for maximal curcumin loading (86%), has shown major morphology directing effect generating triads, tetrads, amongst others and chain-like arrangement (TEM imaging) of the bio-conjugated nanoparticles (80-90 nm). Intonation of the magnetometric parameters of the PEG assisted MNPs on bioconjugation was also evident. The synergistic potency of the partners, the polymer templated iron oxide nanoparticles and curcumin, was unmasked during scavenging of diphenyl picryl hydrazyl (DPPH). The system represents an architecturally appealing, magnetically responsive bio-conjugated system possessing synergistic participation of the partners, with prospective applications in medical domain.

Topics: Biphenyl Compounds; Curcumin; Ferric Compounds; Free Radical Scavengers; Magnetics; Nanoparticles; Particle Size; Picrates; Polyethylene Glycols; Surface Properties

The phytoconstituents of essential oil and ethanol oleoresin of fresh and dry rhizomes of turmeric (Curcuma longa Linn.) were analyzed by GC-MS. The major constituents were aromatic-turmerone (24.4%), alpha-turmerone (20.5%) and beta-turmerone (11.1%) in fresh rhizome and aromatic-turmerone (21.4%), alpha-santalene (7.2%) and aromatic-curcumene (6.6%) in dry rhizome oil. Whereas, in oleoresins, the major components were alpha-turmerone (53.4%), beta-turmerone (18.1%) and aromatic-turmerone (6.2%) in fresh and aromatic-turmerone (9.6%), alpha-santalene (7.8%) and alpha-turmerone (6.5%) in dry rhizome. Results showed that alpha-turmerone, a major component in fresh rhizomes is only minor one in dry rhizomes. Also, the content of beta-turmerone in dry rhizomes is less than a half amount found in fresh rhizomes. The antioxidant properties have been assessed by various lipid peroxidation assays as well as DPPH radical scavenging and metal chelating methods. The essential oil and ethanol oleoresin of fresh rhizomes have higher antioxidant properties as compared dry ones.

Topics: Antioxidants; Biphenyl Compounds; Chelating Agents; Curcuma; Ferrous Compounds; Free Radical Scavengers; Gas Chromatography-Mass Spectrometry; Lipid Peroxidation; Picrates; Plant Extracts; Rhizome; Technology, Pharmaceutical

A series of 46 curcumin related diarylpentanoid analogues were synthesized and evaluated for their anti-inflammatory, antioxidant and anti-tyrosinase activities. Among these compounds 2, 13 and 33 exhibited potent NO inhibitory effect on IFN-gamma/LPS-activated RAW 264.7 cells as compared to L-NAME and curcumin. However, these series of diarylpentanoid analogues were not significantly inhibiting NO scavenging, total radical scavenging and tyrosinase enzyme activities. The results revealed that the biological activity of these diarylpentanoid analogues is most likely due to their action mainly upon inflammatory mediator, inducible nitric oxide synthase (iNOS). The present results showed that compounds 2, 13 and 33 might serve as a useful starting point for the design of improved anti-inflammatory agents.

Topics: Animals; Anti-Inflammatory Agents; Biphenyl Compounds; Cell Line; Cell Survival; Curcumin; Drug Design; Ethylenediamines; Free Radical Scavengers; Humans; Inhibitory Concentration 50; Monophenol Monooxygenase; Nitric Oxide; Picrates; Sulfanilamides

The aim of this work is to clarify the antioxidant abilities of phenolic and enolic hydroxyl groups in curcumin. 1,7-bis(4-benzyloxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (BEC), 1,7-bis(4-hydroxy-3-methoxyphenyl)heptane-3,5-diol (OHC), 1,7-bis(4-hydroxy-3-methoxyphenyl)heptane-3,5-dione (THC), and 1,7-bis(3,4-dihydroxyphenyl)-1,6-heptadiene-3,5-dione (BDC) are synthesized to determine the antioxidant activities by using antiradical assays against 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical, galvinoxyl radical, and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cation radical (ABTS*+) and by protecting DNA and erythrocyte against 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH) induced oxidation. The phenolic hydroxyl is the main group for curcumin to trap DPPH, galvinoxyl, and ABTS*+ radicals. The conjugative system between enolic and phenolic hydroxyl groups is beneficial for curcumin to protect erythrocytes against hemin-induced hemolysis and to protect DNA against AAPH-induced oxidation, but is not beneficial for curcumin to protect erythrocytes against AAPH-induced hemolysis. More hydroxyl groups enhance the antioxidant effectiveness of curcumin in the experimental systems employed herein. Therefore, curcumin acts as an antioxidant through the phenolic hydroxyl group.

Topics: Antioxidants; Benzhydryl Compounds; Benzothiazoles; Biphenyl Compounds; Curcumin; DNA; Free Radical Scavengers; Hemolysis; Humans; Oxidation-Reduction; Phenols; Picrates; Sulfonic Acids

Curcumin (diferuoyl methane) is a phenolic compound and a major component of Curcuma longa L. In the present paper, we determined the antioxidant activity of curcumin by employing various in vitro antioxidant assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH*) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, N,N-dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by the Fe(3+)-Fe(2+) transformation method, superoxide anion radical scavenging by the riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe(2+)) chelating activities. Curcumin inhibited 97.3% lipid peroxidation of linoleic acid emulsion at 15 microg/mL concentration (20 mM). On the other hand, butylated hydroxyanisole (BHA, 123 mM), butylated hydroxytoluene (BHT, 102 mM), alpha-tocopherol (51 mM) and trolox (90 mM) as standard antioxidants indicated inhibition of 95.4, 99.7, 84.6 and 95.6% on peroxidation of linoleic acid emulsion at 45 microg/mL concentration, respectively. In addition, curcumin had an effective DPPH* scavenging, ABTS*(+) scavenging, DMPD*(+) scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe(3+)) reducing power and ferrous ions (Fe(2+)) chelating activities. Also, BHA, BHT, alpha-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. According to the present study, curcumin can be used in the pharmacological and food industry because of these properties.

Topics: alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Curcumin; Free Radical Scavengers; Hydrazines; Hydrogen Peroxide; Iron Chelating Agents; Picrates; Superoxides

One of the pathological hallmarks of Alzheimer's disease is the progressive accumulation of beta-amyloid (Abeta) in the form of senile plaques, and Abeta insult to neuronal cells has been identified as one of the major causes of the onset of the disease. Curcumin, the major and most active antioxidant of Curcuma longa, protects neuronal cells against Abeta-induced toxicity. Therefore, in this study, we investigated the neuroprotective mechanisms by which curcumin acts against Abeta (25-35)-induced toxicity in PC12 cells. Following the exposure of PC12 cells to 10 microM Abeta (25-35) for 24h, significant increases in the level of antioxidant enzymes, and DNA damage were observed, and these increases were accompanied by a decrease in cell viability, and an increase in intracellular calcium levels and tau hyperphosphorylation. In addition, pretreatment of PC12 cells with 10 microg/ml curcumin for 1h significantly reversed the effect of Abeta, by decreasing the oxidative stress, and DNA damage induced by Abeta, as well as attenuating the elevation of intracellular calcium levels and tau hyperphosphorylation induced by Abeta. Taken together, these data indicate that curucmin protected PC12 cells against Abeta-induced neurotoxicity through the inhibition of oxidative damage, intracellular calcium influx, and tau hyperphosphorylation.

Topics: Amyloid beta-Peptides; Animals; Biphenyl Compounds; Calcium; Catalase; Comet Assay; Curcumin; DNA Damage; Electrophoresis, Polyacrylamide Gel; Oxidative Stress; PC12 Cells; Phosphorylation; Picrates; Rats; Superoxide Dismutase; tau Proteins

We investigated the inhibitory effects of curcumin, curcumin derivatives and degradation products on OKT3-induced human peripheral blood mononuclear cell (PBMC) proliferation and the role of their radical scavenging activity.. OKT3-induced human PBMC proliferation was determined by measuring 3H-thymidine incorporation. Radical scavenging activity was evaluated by using an in vitro DPPH assay.. OKT3-induced PBMC proliferation was inhibited by curcumin, isocurcumin, bisdesmethoxy-, diacetyl-, tetrahydro-, hexahydro-, and octahydrocurcumin as well as by vanillin, ferulic acid, and dihydroferulic acid with IC50-values of 2.8, 2.8, 6.4, 1.0, 25, 38, 82, 729, 457, and >1,000 microM, respectively. The investigated substances with the strongest effect on radical scavenging were tetrahydro-, hexahydro-, and octahydrocurcumin with IC50 values of 10.0, 11.7, and 12.3 microM, respectively. IC50-values of dihydroferulic acid, ferulic acid, and curcumin were 19.5, 37, and 40 microM. The substances with the lowest radical scavenging activities were vanillin, isocurcumin, diacetylcurcumin, and bisdesmethoxycurcumin with IC50 values higher than 100 microM each.. Curcuminoid-induced inhibition of OKT3-induced PBMC proliferation depends on the number of carbon atoms and double bonds of the 1,6-heptadiene-3,5-dione structure as well as on the phenolic ring substitutes of the curcuminoids but is not correlated to their respective radical scavenging activity.

Topics: Adult; Biphenyl Compounds; CD3 Complex; Cell Proliferation; Curcumin; Free Radical Scavengers; Humans; In Vitro Techniques; Magnetic Resonance Spectroscopy; Picrates; Spectrophotometry, Infrared; Spectrophotometry, Ultraviolet; T-Lymphocytes

The antioxidant activities of curcumin, its natural demethoxy derivatives (demethoxycurcumin, Dmc and bisdemethoxycurcumin, Bdmc) and metabolite hydrogenated derivatives (tetrahydrocurcumin, THC; hexahydrocurcumin, HHC; octahydrocurcumin; OHC) were comparatively studied using 2,2-diphenyl-1-picrylhydrazyl (DDPH) radical, 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) induced linoleic oxidation and AAPH induced red blood cell hemolysis assays. Hydrogenated derivatives of curcumin exhibited stronger DPPH scavenging activity compared to curcumin and a reference antioxidant, trolox. The scavenging activity significantly decreased in the order THC>HHC=OHC>trolox>curcumin>Dmc>>>Bdmc. Stronger antioxidant activities toward lipid peroxidation and red blood cell hemolysis were also demonstrated in the hydrogenated derivatives. By the model of AAPH induced linoleic oxidation, the stoichiometric number of peroxyl radical that can be trapped per molecule (n) of hydrogenated derivatives were 3.4, 3.8 and 3.1 for THC, HHC and OHC, respectively. The number (n) of curcumin and Dmc were 2.7 and 2.0, respectively, which are comparable to trolox, while it was 1.4 for Bdmc. The inhibition of AAPH induced red blood cell hemolysis significantly decreased in the order OHC>THC=HHC>trolox>curcumin=Dmc. Results in all models demonstrated the lower antioxidant activity of the demethoxy derivatives, suggesting the ortho-methoxyphenolic groups of curcumin are involved in antioxidant activities. On the other hand, hydrogenation at conjugated double bonds of the central seven carbon chain and beta diketone of curcumin to THC, HHC and OHC remarkably enhance antioxidant activity.

Topics: Amidines; Antioxidants; Biphenyl Compounds; Chromans; Curcumin; Diarylheptanoids; Erythrocyte Membrane; Free Radical Scavengers; Free Radicals; Hemolysis; Humans; Hydrogenation; In Vitro Techniques; Linoleic Acid; Lipid Peroxidation; Molecular Structure; Oxidants; Picrates; Structure-Activity Relationship; Time Factors

Guaiacol (2-methoxyphenol) and curcumin [1E,6E-1,7-di(4-hydroxy-3-methoxy-phenyl)-1,6-heptadiene-3,5-dione] were converted into their corresponding glucosides using glucose and an amyloglucosidase from Rhizopus. Guaiacol-alpha-D: -glucoside yields ranged from 3 to 52% with the highest at pH 7.0. Curcumin-bis-alpha-D: -glucoside yields ranged from 3 to 48% with the highest at pH 4.0 with 50% (w/w D: -glucose) of enzyme. The phenolic hydroxyl group of guaiacol and both phenolic hydroxyl groups of curcumin were glucosylated at the C1 carbon of alpha-D: -glucose indicating that the enzymatic reaction is stereospecific. Both guaiacol-alpha-D: -glucoside and curcumin-bis-alpha-D: -glucosides had antioxidant activities.

Topics: Antioxidants; Biphenyl Compounds; Buffers; Chromatography, High Pressure Liquid; Curcumin; Glucan 1,4-alpha-Glucosidase; Glucosides; Glycosylation; Guaiacol; Hydrazines; Hydrogen-Ion Concentration; Kinetics; Molecular Structure; Picrates; Rhizopus; Spectrophotometry, Ultraviolet

The rates of reaction of 1,1-diphenyl-2-picrylhydrazyl (dpph*) radicals with curcumin (CU, 1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), dehydrozingerone (DHZ, "half-curcumin"), and isoeugenol (IE) have been measured in methanol and ethanol and in two non-hydroxylic solvents, dioxane and ethyl acetate, which have about the same hydrogen-bond-accepting abilities as the alcohols. The reactions of all three substrates are orders of magnitude faster in the alcohols, but these high rates can be suppressed to values essentially equal to those in the two non-hydroxylic solvents by the addition of acetic acid. The fast reactions in alcohols are attributed to the reaction of dpph* with the CU, DHZ, and IE anions (see J. Org. Chem. 2003, 68, 3433), a process which we herein name sequential proton loss electron transfer (SPLET). The most acidic group in CU is the central keto-enol moiety. Following CU's ionization to a monoanion, ET from the [-(O)CCHC(O)-](-) moiety to dpph* yields the neutral [-(O)CCHC(O)-]* radical moiety which will be strongly electron withdrawing. Consequently, a phenolic proton is quickly lost into the alcohol solvent. The phenoxide anion so formed undergoes charge migration to produce a neutral phenoxyl radical and the keto-enol anion, i.e., the same product as would be formed by a hydrogen atom transfer (HAT) from the phenolic group of the CU monoanion. The SPLET process cannot occur in a nonionizing solvent. The controversy as to whether the central keto-enol moiety or the peripheral phenolic hydroxyl groups of CU are involved in its radical trapping (antioxidant) activity is therefore resolved. In ionizing solvents, electron-deficient radicals will react with CU by a rapid SPLET process but in nonionizing solvents, or in the presence of acid, they will react by a slower HAT process involving one of the phenolic hydroxyl groups.

Topics: Antioxidants; Biphenyl Compounds; Curcumin; Electron Transport; Models, Chemical; Molecular Structure; Oxidation-Reduction; Picrates; Protons

Turmeric (Curcuma longa) has been used in Indian cooking, and in herbal remedies. Its possible mechanism of action was examined in terms of antioxidant availability during actual cooking conditions and in therapeutic applications using standardized extracts. The assays involve different levels of antioxidant action such as oxygen radical absorbance capacity (ORAC), radical scavenging abilities using 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2'-azobis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS), ferric reducing antioxidant power (FRAP) and protection of membranes examined by inhibition of lipid peroxidation besides the content of phenols and total flavonoids. The aqueous and ethanol extracts of two major preparations of turmeric, corresponding to its use in cooking and medicine, showed significant antioxidant abilities. In conclusion, the studies reveal that the ability of turmeric to scavenge radicals, reduce iron complex and inhibit peroxidation may explain the possible mechanisms by which turmeric exhibits its beneficial effects in relation to its use in cooking and medicine.

Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; Cooking; Curcuma; Ferric Compounds; Free Radical Scavengers; Humans; India; Lipid Peroxidation; Medicine, Traditional; Phytotherapy; Picrates; Plant Extracts; Reactive Oxygen Species; Sulfonic Acids

Hemidesmus indicus R. Br. (Asclepiadaceae) is a well known drug in Ayurveda system of medicine. In the present study, antioxidant activity of methanolic extract of H. indicus root bark was evaluated in several in vitro and ex vivo models. Further, preliminary phytochemical analysis and TLC fingerprint profile of the extract was established to characterize the extract which showed antioxidant properties. The in vitro and ex vivo antioxidant potential of root bark of H. indicus was evaluated in different systems viz. radical scavenging activity by DPPH reduction, superoxide radical scavenging activity in riboflavin/light/NBT system, nitric oxide (NO) radical scavenging activity in sodium nitroprusside/Greiss reagent system and inhibition of lipid peroxidation induced by iron-ADP-ascorbate in liver homogenate and phenylhydrazine induced haemolysis in erythrocyte membrane stabilization study. The extract was found to have different levels of antioxidant properties in the models tested. In scavenging DPPH and superoxide radicals, its activity was intense (EC50 = 18.87 and 19.9 microg/ml respectively) while in scavenging NO radical, it was moderate. It also inhibited lipid peroxidation of liver homogenate (EC50 = 43.8 microg/ml) and the haemolysis induced by phenylhydrazine (EC50 = 9.74 microg/ml) confirming the membrane stabilization activity. The free radical scavenging property may be one of the mechanisms by which this drug is effective in several free radical mediated disease conditions.

Topics: alpha-Tocopherol; Animals; Antioxidants; Apocynaceae; Ascorbic Acid; Biphenyl Compounds; Chromatography, Thin Layer; Curcumin; Erythrocyte Membrane; Free Radical Scavengers; Hemolysis; Lipid Peroxidation; Liver; Medicine, Ayurvedic; Nitric Oxide; Oxidants; Phenylhydrazines; Picrates; Plant Bark; Plant Extracts; Plant Roots; Pyrogallol; Rats; Superoxides

Three natural curcuminoids (curcumin (CAS 458-37-7), demethoxycurcumin, bisdemethoxycurcumin) and acetylcurcumin were compared for their ability to scavenge superoxide radicals and to interact with 1,1-diphenyl-2-picryl-hydrazyl (DPPH) stable free radicals. The results showed that curcumin is the most potent scavenger of superoxide radicals followed by demethoxycurcumin and bisdemethoxycurcumin. Acetylcurcumin was inactive. Interaction with DPPH showed a similar activity profile. The study indicates that the phenolic group is essential for the free radical scavenging activity and presence of methoxy group further increases the activity.

Topics: Bepridil; Biphenyl Compounds; Curcumin; Free Radical Scavengers; Free Radicals; Picrates; Structure-Activity Relationship; Superoxides; Xanthine Oxidase

Phenolic and non phenolic derivatives of phenyl styryl ketones were synthesized and evaluated as in vitro inhibitors of iron and cumene hydroperoxide dependent lipid peroxidation in rat brain homogenates. The compounds were also tested for antioxidant activity in phosphatidylcholine liposomes. Phenyl 3,5-di-tert-butyl-4-hydroxystyryl ketone was found to be the most potent inhibitor of peroxidation among all the compounds tested. It was found to be more active than vitamin E. It also reduced the stable free radical 1,1-diphenyl-2-picrylhydrazyl to an appreciable extent.

Topics: Animals; Antioxidants; Benzene Derivatives; Bepridil; Biphenyl Compounds; Brain; Curcumin; Dose-Response Relationship, Drug; Female; In Vitro Techniques; Iron Compounds; Lipid Peroxidation; Liposomes; Male; Picrates; Pregnatrienes; Rats; Rats, Inbred Strains; Thiobarbituric Acid Reactive Substances; Time Factors; Vitamin E