lignans and 1-1-diphenyl-2-picrylhydrazyl

Topics: Antifungal Agents; Antioxidants; Basidiomycota; Biphenyl Compounds; Dose-Response Relationship, Drug; Fusarium; Hydroxybenzoates; Lignans; Microbial Sensitivity Tests; Penicillium; Picrates; Plant Extracts; Polyporaceae; Schizophyllum; Wood

From MeOH-soluble fraction of the flowers of

Topics: Biphenyl Compounds; Flowers; Free Radical Scavengers; Hibiscus; Lignans; Picrates

Defatted-sesame meal (DSM), a byproduct of sesame oil, has attracted considerable interest in the food industry because of its strong antioxidant activity. The aim of this study was to measure the content and distribution of lignans in DSM and evaluate their antioxidant activity after thermal processing and in vitro digestion. The results showed that the sesame lignans (SL) content and antioxidant activity were significantly influenced by the temperature and time during thermal preparation, and the maximum antioxidant potency composite index (ACI) was obtained after roasting the samples at 240 °C for 20 min. As sesame seed was processed with longer time and higher temperature, more pinoresinol diglucoside (PD) and sesamol were measured in DSM. According to the correlation matrix under thermal preparation, a significant contribution to the antioxidant potency of DSM was discovered. After in vitro digestion, the release amount of lignans increased by 19.6%, and the values of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ACI gradually declined after digestion, with a 40% decrease in both the DPPH radical scavenging activity and the ACI from oral to intestinal phase. These results could be used to help improve the bioavailability of SL and obtaining high quality sesame byproducts.

Topics: Antioxidants; Biological Availability; Biphenyl Compounds; Hot Temperature; Hydrolysis; In Vitro Techniques; Lignans; Models, Biological; Picrates; Seeds; Sesamum

A new series of furofuran lignans containing catechol moiety were prepared from the reactions between lignans and a variety of phenolics. All 22 products obtained were evaluated against three different α-glucosidases (maltase, sucrase and Baker's yeast glucosidase) and DPPH radical. Of furofuran lignans evaluated, β-14, having two catechol moieties and one acetoxy group, was the most potent inhibitor against Baker's yeast, maltase, and sucrase with IC

Topics: alpha-Glucosidases; Biphenyl Compounds; Dose-Response Relationship, Drug; Free Radical Scavengers; Glycoside Hydrolase Inhibitors; Hypoglycemic Agents; Kinetics; Lignans; Models, Molecular; Molecular Structure; Picrates; Saccharomyces cerevisiae; Structure-Activity Relationship

Hairy root culture is a promising alternative method for the production of secondary metabolites. In this study, transformed root of Linum usitatissimum was established using Agrobacterium rhizogenes A4 strain from root cultures for lignans, phenolic acids and antioxidant capacity determination. Total lignin content (secoisolariciresinol diglucoside, secoisolariciresinol and matairesinol) was 55.5% higher in transformed root cultures than in the non-transformed root culture. Secoisolariciresinol was detected in higher concentration (2.107 μmol/g DM) in the transformed root culture than non-transformed culture (1.099 μmol/g DM). Secoisolariciresinol diglucoside and matairesinol were exclusively detected in the transformed root culture, but were not found in the non-transformed root culture. The overall production of phenolic acids in transformed roots was approximately 3.5 times higher than that of the corresponding non-transformed culture. Free radical scavenging DPPH˙ and ABTS˙

Topics: Antioxidants; Biphenyl Compounds; Butylene Glycols; Flax; Furans; Glucosides; Hydroxybenzoates; Lignans; Picrates; Plant Roots; Tissue Culture Techniques

Twenty Schisandra samples were collected from different locations. Contents of 7 lignans in the samples were determined and analyzed by HPLC method coupled with hierarchical clustering analysis (HCA) and principal component analysis (PCA), and the antioxidant capacity of Schisandra from the different locations was evaluated by reducing power, ferric thiocyanate (FTC) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) assay. The results showed that there was a significant difference in the content of lignans between Schisandra chinensis and Schisandra sphenanthera. The Schisandra sphenanthera samples in the southwest of China were significantly different from those from the other locations. The antioxidant capacity of Schisandra chinensis was significantly superior to that of Schisandra sphenanthera, and the main antioxidant components were schisandrol A, schisandrol B and schisandrin B based on the result of discrimination analyses. The differences in the chemical composition and antioxidant activity of lignans in Schisandra chinensis and Schisandra sphenanthera from the different locations were investigated in this study, which may provide an experimental basis for the quality control of Schisandra.

Topics: Antioxidants; Biphenyl Compounds; China; Democratic People's Republic of Korea; Discriminant Analysis; Lignans; Picrates; Schisandra

The lignan 7'-hydroxymatairesinol (1), extracted from the knotwoods of fir (Abies alba), spruce (Picea abies), and Douglas fir (Pseudotsuga menziesii), exhibited unexpected reactivity when esterification reactions were attempted on the hydroxy group at position C-7'. To circumvent the rapid intramolecular cyclization procedure, leading quantitatively to the lignan conidendrin (7), a simple strategy for 7'-esterification of 1 under mild conditions (three steps, up to 80% overall yield) was developed. Compared to hydroxymatairesinol (1) (log K'

Topics: alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Lignans; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Picea; Picrates; Pinus; Stereoisomerism; Tetrahydronaphthalenes

Inhibition of intestinal α-amylase and α-glucosidase is an important strategy to regulate diabetes mellitus (DM). Antioxidants from plants are widely regarded in the prevention of diabetes. Fruits of Elettaria cardamomum (L.) Maton (Zingiberaceae) and Piper cubeba L. f. (Piperaceae) and flowers of Plumeria rubra L. (Apocynaceae) are traditionally used to cure DM in different countries. However, the role of these plants has been grossly under reported and is yet to receive proper scientific evaluation with respect to understand their traditional role in the management of diabetes especially as digestive enzymes inhibitors. Hence, methanol and aqueous extracts of the aforementioned plants were evaluated for their in vitro α-glucosidase and α-amylase inhibition at 1 mg/mL and quantification of their antioxidant properties (DPPH, FRAP tests, total phenolic and total flavonoids contents). In vitro optimization studies for the extracts were also performed to enhance in vitro biological activities. The % inhibition of α-glucosidase by the aqueous extracts of the fruits of E. cardamomum, P. cubeba and flowers of P. rubra were 10.41 (0.03), 95.19 (0.01), and -2.92 (0.03), while the methanol extracts exhibited % inhibition 13.73 (0.02), 92.77 (0.01), and -0.98 (0.01), respectively. The % inhibition of α-amylase by the aqueous extracts were 82.99 (0.01), 64.35 (0.01), and 20.28 (0.02), while the methanol extracts displayed % inhibition 39.93 (0.01), 31.06 (0.02), and 39.40 (0.01), respectively. Aqueous extracts displayed good in vitro antidiabetic and antioxidant activities. Moreover, in vitro optimization experiments helped to increase the α-glucosidase inhibitory activity of E. cardamomum. Our findings further justify the traditional claims of these plants as folk medicines to manage diabetes, however, through digestive enzymes inhibition effect.

Topics: Antioxidants; Apocynaceae; Biphenyl Compounds; Chlorides; Ferric Compounds; Flowers; Fruit; Glycoside Hydrolase Inhibitors; Hypoglycemic Agents; Lignans; Methanol; Oxidation-Reduction; Phytotherapy; Picrates; Piper; Plant Extracts; Plants, Medicinal; Solvents; Water; Zingiberaceae

The biphenyl neolignan honokiol is a neuroprotectant which has been proposed as a treatment for central nervous system disorders such as Alzheimer's disease (AD). The death of cholinergic neurons in AD is attributed to multiple factors, including accumulation and fibrillation of amyloid beta peptide (Aβ) within the brain; metal ion toxicity; and oxidative stress. In this study, we used a transgenic Caenorhabditis elegans model expressing full length Aβ

Topics: Amyloid beta-Peptides; Animals; Biphenyl Compounds; Caenorhabditis elegans; Catechin; Chelating Agents; Cholinesterase Inhibitors; Drug Stability; Free Radical Scavengers; Humans; Iron; Lignans; Molecular Docking Simulation; Molecular Structure; Neuroprotective Agents; Paralysis; Peptide Fragments; Picrates; Protein Aggregation, Pathological; Protein Multimerization; Resveratrol; Stilbenes

Nine new phenylpropanoids, one new coumarin, and 43 known polyphenols were isolated from wolfberry. Their structures were determined by spectroscopic analyses, chemical methods, and comparison of NMR data. Polyphenols, an important type of natural products, are notable constituents in wolfberry. 53 polyphenols, including 28 phenylpropanoids, four coumarins, eight lignans, five flavonoids, three isoflavonoids, two chlorogenic acid derivatives, and three other constituents, were identified from wolfberry. Lignans and isoflavonoids were firstly reported from wolfberry. 22 known polyphenols were the first isolates from the genus Lycium. This research presents a systematic study on wolfberry polyphenols, including their bioactivities. All these compounds exhibited oxygen radical absorbance capacity (ORAC), and some compounds displayed DPPH radical scavenging activity. One compound had acetylcholinesterase inhibitory activity. The discovery of new polyphenols and their bioactivities is beneficial for understanding the scientific basis of the effects of wolfberry.

Topics: Acetylcholinesterase; Alzheimer Disease; Benzothiazoles; Biphenyl Compounds; Chlorogenic Acid; Cholinesterase Inhibitors; Flavonoids; Food Analysis; Free Radical Scavengers; Free Radicals; Lignans; Lycium; Molecular Structure; Oxygen; Picrates; Plant Extracts; Polyphenols; Spectrophotometry, Ultraviolet; Structure-Activity Relationship; Thiazoles

In the search for biologically active compounds from the roots of Bupleurum chinense D C., phytochemical investigation of its ethanol extract led to the isolation and identification of a new 8-O-4' neolignan glucoside, saikolignanoside A (1), along with eight known lignans (2-9). Their structures were determined on the basis of IR, UV, HRESIMS, and NMR spectroscopic analyses. The antioxidant and cytotoxic effects of isolated compounds were evaluated in vitro. The isolated compounds (IC

Topics: Antineoplastic Agents, Phytogenic; Antioxidants; Benzothiazoles; Biphenyl Compounds; Bupleurum; Cell Line, Tumor; Drug Screening Assays, Antitumor; Fluorouracil; Humans; Inhibitory Concentration 50; Lignans; MCF-7 Cells; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Picrates; Plant Roots

Chemical investigation of Cassia grandis leaves resulted in the isolation of the new 2-methoxy 6,7,2',6'-tetrahydroxy flavanone 6-O-β-glucoside together with the known flavonol glycosides, kaempferol-3-O-α-rhamnoside, and quercetin 3-O-α-rhamnoside. The structure assign ments were based on conventional analytical methods and confirmed by HRFTESIMS, 1H and 13C NMR, COSY, HSQC and HMBC data. The total phenolic content of the extract was estimated by Folin-Ciocalteu's method. The antioxidant capacity was investigated using DPPH radical scavenging assay. The ethyl acetate and the n-butanol fractions showed poor cytotoxic activity only at high concentrations against the three different cancer cell lines, hepatocellular (HepG-2), breast (MCF-7), and prostate (PC3) by the neutral red uptake assay.

Topics: Antineoplastic Agents, Phytogenic; Antioxidants; Biphenyl Compounds; Cassia; Cell Line, Tumor; Cell Survival; Female; Free Radical Scavengers; Furans; Humans; Lignans; Magnetic Resonance Spectroscopy; Male; Phenols; Picrates; Plant Extracts; Plant Leaves

An efficient method for the rapid extraction, separation and purification of bioactive lignans, arctiin and arctigenin, from Fructus arctii by microwave-assisted extraction coupled with high-speed countercurrent chromatography was developed. The optimal extraction conditions of arctiin and arctigenin were evaluated by orthogonal array. Arctigenin could be converted from arctiin by hydrochloric acid hydrolysis. The separations were performed at a preparative scale with two-phase solvents composed of ethyl acetate-ethanol-water (5 : 1 : 5, v/v/v) for arctiin, and n-hexane-ethyl acetate-ethanol-water (4 : 4 : 3 : 4, v/v/v/v) for arctigenin. From 500 mg of crude extract sample, 122.3 mg of arctiin and 45.7 mg of arctigenin were obtained with the purity of 98.46 and 96.57%, and the recovery of 94.3 and 81.6%, respectively. Their structures were determined by comparison with the high-performance liquid chromatography retention time of standard substance as well as UV, FT-IR, electrospray ion source (ESI)-MS, (1)H-NMR and (13)C-NMR spectrum. According to the antioxidant activity assay, arctigenin had stronger 1,1-diphenyl-2-picrylhydrazyl free radicals scavenging activity.

Topics: Acetates; Arctium; Biphenyl Compounds; Chromatography, High Pressure Liquid; Countercurrent Distribution; Ethanol; Free Radical Scavengers; Furans; Glucosides; Hexanes; Hydrochloric Acid; Hydrolysis; Lignans; Liquid-Liquid Extraction; Microwaves; Picrates; Plant Extracts; Solvents; Water

Aristolochic acids (AA) are nephrotoxic agents found in Aristolochia species whose consumption leads to the onset of a progressive tubulointerstitial fibrosis. This AA-nephropathy was first reported during the Belgian outbreak of the 1990's in which more than a hundred patients consumed slimming pills containing an Aristolochia species and Magnolia officinalis. The patients developed an end-stage kidney disease requiring dialysis or transplantation. Magnolol and honokiol are bioactive compounds from M. officinalis known for their potent antioxidant activity. As they can alleviate oxidative stress, we investigated their respective effects on AA-mediated tubulotoxicity using HK-2 cells. Magnolol and honokiol were able to reduce the oxidative stress associated with AA-treatment. Cytotoxicity alleviation was further investigated and overall cell viability measurements unexpectedly revealed that both compounds worsened the survival of AA-treated cells. Flow cytometry analyses of annexin V/PI stained cells indicated that the lignans efficiently prevented AA-induced apoptosis; but favored necrosis. Microscopy observations highlighted extensive vacuolization; other types of cell death, including autophagy, paraptosis or accelerated senescence were excluded. Ki-67 index and cell cycle analysis indicated that both magnolol and honokiol inhibited proliferation by blocking the cell cycle at the G1 phase; they also prevented the AA-induced G2/M arrest.

Topics: Aristolochic Acids; Biphenyl Compounds; Cell Cycle; Cell Line; Free Radical Scavengers; Humans; Kidney Tubules; Lignans; Molecular Structure; Oxidative Stress; Picrates

Eleven new lignans and neolignans, named acortatarinowins G-N (1-8), including three pairs of enantiomers (1a/1b-3a/3b) and five optically pure lignans and neolignans (4-8), along with five known analogs (9-14), were isolated from the rhizomes of Acorus tatarinowii Schott. Compounds 1-3 were successfully separated by chiral HPLC to afford 1a/1b-3a/3b. The planar structures of 1-8 were elucidated by extensive spectroscopic analyses including HRESIMS and NMR. Their absolute configurations were determined by analyses of single-crystal X-ray diffraction and a modified Mosher's method, assisted by experimental and calculated electronic circular dichroism (ECD) data. Compounds 1a and 1b were rare 7,8'-epoxy-8,7'-oxyneolignane. Compounds 1-8 were evaluated for their antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl (DPPH) reducing antioxidant power assay. Compound 6, exhibiting strong DPPH radical scavenging capacity with IC50 value of 16.4 ± 0.22 μg/mL, could interpret the herbal traditional usage.

Topics: Acorus; Antioxidants; Biphenyl Compounds; Circular Dichroism; Crystallography, X-Ray; Lignans; Magnetic Resonance Spectroscopy; Picrates

Two new norditerpenoids, miltiolactones A and B (1a, 1b); seven new neolignans, miltiolignanolides A-G (2a, 2b and 3a, 3b and 4a, 4b, and 5) were obtained from the root extract of Salvia miltiorrhiza. Using HPLC separation with a chiral column, compounds 1-4 were found to exist as four pairs of enantiomers. Compounds 2-5 are novel neolignans with a dibenzocycloheptatriene ring system, which form an unprecedented 6/7/6 carbon skeleton. The structures were established via extensive spectroscopic analysis, and experimental and calculated electronic circular dichroism (ECD) spectra, and compound 1 was also elucidated by X-ray diffraction experiments. Compounds 2a and 2b significantly increased the viability of H9c2 cells from H

Topics: Benzothiazoles; Biphenyl Compounds; Cell Line; Diterpenes; Free Radical Scavengers; Lignans; Microglia; Models, Molecular; Molecular Conformation; Nitric Oxide; Picrates; Plant Roots; Salvia miltiorrhiza; Sulfonic Acids

Seven new neolignans (1-2, 7-11) and five known compounds (3-6, 12) were isolated from the 70% EtOH extract of hawthorn seeds. Their structures were determined by spectroscopic analyses. The antioxidant and anti-inflammatory activities of all the isolates were investigated. Most of the isolates showed moderate radical scavenging activity in the DPPH assay and significant activities in the ABTS and FRAP assays. Furthermore, compounds 7-12 exhibited marked nitric oxide (NO) inhibition and compounds 1-4 had a potent necrosis factor-α (TNF-α) inhibitory effect. The results we obtained showed that hawthorn seeds can be regarded as a potential new and cheap source of antioxidants and inflammation inhibitors.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Benzothiazoles; Biphenyl Compounds; Crataegus; Lignans; Mice; Nitric Oxide; Picrates; Plant Extracts; RAW 264.7 Cells; Seeds; Sulfonic Acids; Tumor Necrosis Factor-alpha

Background. Liver diseases still represent a major health burden worldwide. Moreover, medicinal plants have gained popularity in the treatment of several diseases including liver. Thus, the present study was to evaluate the effectiveness of Piper cubeba fruits in the amelioration of CCl4-induced liver injuries and oxidative damage in the rodent model. Methods. Hepatoprotective activity was assessed using various biochemical parameters like SGOT, SGPT, γ-GGT, ALP, total bilirubin, LDH, and total protein. Meanwhile, in vivo antioxidant activities as LPO, NP-SH, and CAT were measured in rat liver as well as mRNA expression of cytokines such as TNFα, IL-6, and IL-10 and stress related genes iNOS and HO-1 were determined by RT-PCR. The extent of liver damage was also analyzed through histopathological observations. Results. Treatment with PCEE significantly and dose dependently prevented drug induced increase in serum levels of hepatic enzymes. Furthermore, PCEE significantly reduced the lipid peroxidation in the liver tissue and restored activities of defense antioxidant enzymes NP-SH and CAT towards normal levels. The administration of PCEE significantly downregulated the CCl4-induced proinflammatory cytokines TNFα and IL-6 mRNA expression in dose dependent manner, while it upregulated the IL-10 and induced hepatoprotective effect by downregulating mRNA expression of iNOS and HO-1 gene.

Topics: Animals; Antioxidants; Biphenyl Compounds; Carbon Tetrachloride; Catalase; Chemical and Drug Induced Liver Injury; Cytokines; Disease Models, Animal; Ethanol; Free Radical Scavengers; Lignans; Liver; Male; Malondialdehyde; Oxidative Stress; Phytochemicals; Picrates; Piper; Plant Extracts; Protective Agents; Rats, Wistar; RNA, Messenger; Sulfhydryl Compounds

The Stewartia koreana Nakai (SK) had been used in oriental traditional medicine as a remedy for acute gastroenteritis, liver diseases, quadriplegia and pain. The antioxidant activity guided isolation 80% methyl extract from stems of SK yielded eight phenolic compounds. We evaluated the anti-oxidative and anti-inflammatory effects of these compounds via assays of 1,1-diphenyl-2-picrylhydazyl (DPPH) radicals and inhibition of nitric oxide (NO) production in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. The results demonstrated that syringaresinol (6) exhibited significant DPPH radical-scavenging activity and inhibitory effects on NO production compared with its positive controls, ascorbic acid and L-NMMA, respectively.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Free Radical Scavengers; Furans; Lignans; Lipopolysaccharides; Macrophages; Mice; Molecular Structure; Nitric Oxide; omega-N-Methylarginine; Oxidation-Reduction; Phenols; Picrates; Plant Stems; Theaceae

Two rare 7,8-seco-lignans (1, 2), three new lignan glycosides (3, 4a, 4b), and 10 known lignans (5-14) were isolated from the fruit of Schisandra glaucescens Diels. The absolute configurations of 1 and 2 were determined by comparing their experimental and calculated electronic circular dichroism spectra. The molecular structures of the new compounds (3, 4a, and 4b), including their absolute configurations, were determined using various spectroscopic methods and hydrolysis reactions. The antioxidant activities of the isolated compounds were tested using 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power assays. Compounds 4, 7, 8, 10, 11, and 12 exhibited antioxidant activities of varying potential in both assays. Of these compounds, 7 showed the strongest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, with IC50 values of 15.7 (150 μM DPPH) and 34.6 μM (300 μM DPPH), respectively, and 4, 12, and 7 displayed higher total antioxidant activities than Trolox in the ferric reducing antioxidant power assay. The neuroprotective effects of these compounds against Aβ25-35-induced cell death in SH-SY5Y cells were also investigated. Compounds 1, 2, 6, 7, 8, 11, and 12 exhibited statistically significant neuroprotective effects against Aβ25-35-induced SH-SY5Y cell death compared with the group treated only with Aβ25-35.

Topics: Amyloid beta-Peptides; Antioxidants; Biphenyl Compounds; Chromans; Drugs, Chinese Herbal; Fruit; Glycosides; Inhibitory Concentration 50; Lignans; Molecular Structure; Neuroprotective Agents; Nuclear Magnetic Resonance, Biomolecular; Oxidation-Reduction; Peptide Fragments; Picrates; Plant Extracts; Schisandra

A new phenyldihydronaphthalene-type lignan, vitexdoin F (1), along with 22 known lignan derivatives (2-23) was isolated from the seeds of Vitex negundo var. cannabifolia. Their structures were established by comprehensive 1D and 2D NMR spectroscopic analyses. The antioxidant activities of these lignans were evaluated through 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assays, and 16 of these isolates exhibited obvious radical-scavenging effect on the stable-free radical, DPPH.

Topics: Antioxidants; Biphenyl Compounds; Free Radical Scavengers; Lignans; Nuclear Magnetic Resonance, Biomolecular; Picrates; Seeds; Vitex

A phytochemical investigation on the ethyl acetate soluble fraction of Zanthoxylum armatum led in the isolation of two new prenylated alkaloids 2,6,7-trimethoxy-8-(3-methyl-2-butenyl)carbazole-3-carbaldehyde (1) and methyl-2,6,7-trimethoxy-8-(3-methyl-2-butenyl)carbazole-3-carboxylate (2), along with three known lignans cisamin (3), methyl pirpirtol (4), and fargesin (5) and one known alkaloid dictamine (6). Their structures were established on the basis of spectroscopic and crystallographic analysis and by comparison of the data with those in the literature. All the isolated compounds were screened for the DPPH free radical scavenging activity. Compounds 1, 2, and 6 showed profound activity while compounds 3-5 showed moderate activity.

Topics: Alkaloids; Benzodioxoles; Biphenyl Compounds; Carbazoles; Free Radical Scavengers; Lignans; Molecular Structure; Pakistan; Picrates; Prenylation; Quinolines; Zanthoxylum

In the course of screening for neuroprotective natural products, Magnoliae Cortex showed potent inhibition of hippocampal neuronal HT22 cell death. Obovatol, honokiol, and magnolol were isolated from the ethanolic extract of Magnoliae Cortex. Isolated compounds obovatol, honokiol, and magnolol were protective against 5mM glutamate-induced cell death. When cells were stressed using glutamate, cell viability decreased to 16.98±4.58% over the control (100.00±10.15%). In contrast, 10 μM obovatol, 10 μM honokiol, and 50 μM magnolol increased cell viability to 91.80±1.70%, 93.59±1.93%, and 85.36±7.40%, respectively. The neuroprotective effects of obovatol and honokiol were attributable to the inhibition of intracellular reactive oxygen species production, followed by protection of the mitochondrial membrane potential (ΔΨm), recovery of Bcl-2 and Bid levels, inhibition of apoptosis-inducing factor expression, and phosphorylation of mitogen-activated protein kinases such as p38 kinases, extracellular signal-regulated kinases, and c-Jun N-terminal kinases. On the contrary, magnolol did not show any significant effect on the ΔΨm and apoptotic factors. Among three compounds, obovatol most strongly scavenged 2,2-diphenyl-1-picrylhydrazyl radicals and inhibited the elevation of intracellular reactive oxygen species levels in glutamate-stressed HT22 cells. These data suggest that obovatol and honokiol may have clinical applications for preventing neurodegenerative disorders.

Topics: Animals; Apoptosis; Apoptosis Inducing Factor; BH3 Interacting Domain Death Agonist Protein; Biphenyl Compounds; Cell Death; Cell Line; Cell Survival; Extracellular Signal-Regulated MAP Kinases; Glutamic Acid; JNK Mitogen-Activated Protein Kinases; Lignans; Magnoliaceae; Membrane Potential, Mitochondrial; Mice; Neurons; Neuroprotective Agents; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Phenyl Ethers; Phosphorylation; Picrates; Plant Extracts; Reactive Oxygen Species; Signal Transduction

Four new 8,8',7,2'-lignans, (+)-ovafolinin B-9'-O-β-d-glucopyranoside (1), (-)-ovafolinin B-9'-O-β-d-glucopyranoside (2), (+)-ovafolinin E-9'-O-β-d-glucopyranoside (3), and (-)-ovafolinin E-9'-O-β-d-glucopyranoside (4), two neolignans, eusiderin N (5) and (7S,8R)-3,5,5'-trimethoxy-4',7-epoxy-8,3'-neolignan-9,9'-diol-4-O-β-d-xylopyranoside (6), and two new chromone glycosides, 5,7-dihydroxy-4H-chromen-4-one-3-O-β-d-glucopyranoside (7) and 5,7-dihydroxy-4H-chromen-4-one-3-O-β-d-xylopyranoside (8), together with 25 known compounds, were isolated from the stems of Eurya japonica. Structural elucidation of compounds 1-8 was established by spectroscopic methods, especially 2D NMR techniques, electronic circular dichroism data, and comparison with reported data. The isolates were evaluated for antioxidant and anti-NO production activities. Compounds 1, 2, 12-20, and 29 (ED50 23.40 μM for 1) demonstrated potent antioxidant activity compared to the positive control α-tocopherol (ED50 27.21 μM). On the other hand, compounds 1, 2, 7-9, 12-20, and 32 showed only weak anti-NO production activity when compared to the positive control quercetin.

Topics: alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Chromones; Glycosides; Lignans; Molecular Structure; Nitric Oxide; Nuclear Magnetic Resonance, Biomolecular; Picrates; Plant Stems; Quercetin; Stereoisomerism; Taiwan; Theaceae

Phytochemical investigation of the leaves of Ribes nigrum resulted in the isolation of fourteen compounds, including four 7,7'-epoxylignans, three tetrahydrofuran-type sesquilignans, and a spirocyclic dilignan. Their structures were elucidated by extensive spectroscopic analyses and by chemical transformations. The isolated compounds were evaluated for their antioxidant activities using superoxide anion scavenging assay and DPPH free radical scavenging assay. Ribesin D and ribesin G showed the most potent superoxide anion scavenging activity with EC50 values of 1.24 and 1.12 μM, respectively, and the structure-activity relationship was discussed.

Topics: Antioxidants; Biphenyl Compounds; Furans; Lignans; Molecular Structure; Picrates; Plant Extracts; Plant Leaves; Ribes; Structure-Activity Relationship; Superoxides

Three new lignans (1, 2, and 8) and ten known ones (3-7, 9-13) were isolated from the roots of Vladimiria muliensis. Their structures and configurations were elucidated by means of spectroscopic techniques (IR, MS, NMR, and CD) and chemical methods. The isolated compounds were evaluated for their antioxidant and antibacterial activities. The antioxidant activity was the greatest for lignans 7 and 10 with IC50 values of 11.2 and 7.3 µM against DPPH radical, and of 1.6 and 1.7 µM against ABTS+ radical, respectively. Moreover, 7 also displayed broad-spectrum antibacterial activity with MIC values around 7.25 µg/mL.

Topics: Anti-Bacterial Agents; Antioxidants; Asteraceae; Benzothiazoles; Biphenyl Compounds; Lignans; Microbial Sensitivity Tests; Molecular Structure; Picrates; Plant Extracts; Plant Roots; Sulfonic Acids

Eight new dihydrobenzofuran neolignans, pinnatifidanin C I-VIII (1-8), together with two known analogs (9-10) were isolated from the seeds of Crataegus pinnatifida. Their structures were elucidated by spectroscopic analyses, especially 1D, 2D NMR and CD spectra. The cytotoxic activities of all isolates against human cancer cell lines were assayed, and most interestingly, compound 10 revealed preferred cytotoxicity on the HT-1080 cell line and displayed much stronger inhibitory activity (IC50=8.86 μM) compared with positive control 5-fluorouracil (IC50=35.62 μM). Meanwhile, antioxidant activities of all the isolates were evaluated using 2,2-diphenyl-1-pikrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays, and the results showed that most of the isolates exhibited potent antioxidant activity.

Topics: Antineoplastic Agents, Phytogenic; Antioxidants; Benzofurans; Benzothiazoles; Biphenyl Compounds; Cell Line, Tumor; Crataegus; Humans; Inhibitory Concentration 50; Lignans; Molecular Structure; Neoplasms; Phytotherapy; Picrates; Plant Extracts; Seeds; Sulfonic Acids

From the stems of Liriodendron tulipifera, seventeen known compounds have been extracted, isolated and purified. By using spectroscopic analysis, the structures of these pure constituents were determined as three lignans, four steroids and ten benzenoids. Identified compounds were screened for antioxidant abilities using: 1,1-diphenyl-2-picrylhydrazul (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging free radical activity assays; metal chelating power test; and ferric reducing/antioxidant power (FRAP) examination. The result revealed that seventeen compounds had potential anti-oxidative capabilities. In addition, the anti-tyrosinase effect was determined by calculating the hydroxylation of L-tyrosine to L-dopa and the oxidization of L-dopa to dopaquinone, according to in vitro mushroom tyrosinase evaluation platform. Furthermore, based on assays on B16F10 cell line, our data suggest that five compounds isolated from L. tulipifera would be able to inhibit tyrosinase activity and reduce the melanin content in animal cells. Therefore, some of the examined compounds could be potentially used in the cosmetic skin whitening business, therapeutic applications or the food industry.

Topics: Animals; Antioxidants; Benzene Derivatives; Biphenyl Compounds; Cell Line, Tumor; Cell Survival; Dose-Response Relationship, Drug; Free Radical Scavengers; Lignans; Liriodendron; Melanins; Mice; Molecular Structure; Monophenol Monooxygenase; Picrates; Plant Extracts; Plant Stems; Steroids

Antioxidants could be promising agents for management of oxidative stress-related diseases. New biologically active compounds, belonging to a rare class of natural lignans with antiangiogenic, antitumoral and DNA intercalating properties, have been recently synthesized. These compounds are benzo[kl]xanthene lignans (1,2) and dihydrobenzofuran neolignans (3,4). The radical scavenging and chain-breaking antioxidant activities of compounds 1-4 were studied by applying different methods: radical scavenging activity by DPPH rapid test, chain-breaking antioxidant activity and quantum chemical calculations. All studied compounds were found to be active as DPPH scavengers but reaction time with DPPH and compounds' concentrations influenced deeply the evaluation. The highest values of radical scavenging activity (%RSAmax) and largest rate constants for reaction with DPPH were obtained for compounds 2 and 3. Comparison of %RSAmax with that of standard antioxidants DL-α-tocopherol (TOH), caffeic acid (CA) and butylated hydroxyl toluene (BHT) give the following new order of %RSA max: TOH (61.1%) > CA (58.6%) > 3 (36.3%) > 2 (28.1%) > 4 (6.7%) > 1 (3.6%) = BHT (3.6%). Chain-breaking antioxidant activities of individual compounds (0.1-1.0 mM) and of their equimolar binary mixtures (0.1 mM) with TOH were determined from the kinetic curves of lipid autoxidation at 80 °C. On the basis of a comparable kinetic analysis with standard antioxidants a new order of the antioxidant efficiency (i.e., protection factor, PF) of compounds 1-4 were obtained: 2 (7.2) ≥ TOH (7.0) ≥ CA (6.7) > 1 (3.1) > 3 (2.2) > ferulic acid FA (1.5) > 4 (0.6); and of the antioxidant reactivity (i.e. inhibition degree, ID): 2 (44.0) >> TOH (18.7) >> CA (9.3) >> 1 (8.4) > 3 (2.8) > FA (1.0) > 4 (0.9). The important role of the catecholic structure in these compounds, which is responsible for the high chain-breaking antioxidant activity, is discussed and a reaction mechanism is proposed. Higher oxidation stability of the lipid substrate was found in the presence of equimolar binary mixtures 2 + TOH, 3 + TOH and 4 + TOH. However, an actual synergism was only obtained for the binary mixtures with compounds 3 and 4. The geometries of compounds and all possible phenoxyl radicals were optimized using density functional theory. For description of the scavenging activity bond dissociation enthalpies (BDE), HOMO energies and spin densities were employed. The best correlation between theoretical and experimental d

Topics: alpha-Tocopherol; Antioxidants; Benzofurans; Biphenyl Compounds; Butylated Hydroxytoluene; Caffeic Acids; Free Radical Scavengers; Hot Temperature; Kinetics; Lignans; Lipids; Oxidation-Reduction; Phenols; Picrates; Quantum Theory; Solutions; Structure-Activity Relationship; Thermodynamics; Xanthenes

The 70% alcohol extract of Oxytropis myriophylla (PALL.) DC. (Leguminosae) exhibited high radical scavenging activity (IC(50) value: 88.0 µg mL(-1) and 86.7 µg mL(-1)) on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays. Further chemical investigation led the isolation of one new lignan, namely myriophylloside G (1), together with three known compounds. Their structural elucidations of all the compounds were based on extensive spectroscopic methods, including HRESIMS and 2D NMR experiments (HSQC, HMBC and (1)H-(1)HCOSY) and by comparison with reference values.

Topics: Benzothiazoles; Biphenyl Compounds; Flavonoids; Free Radical Scavengers; Lignans; Magnetic Resonance Spectroscopy; Molecular Structure; Oxytropis; Picrates; Plant Extracts; Sulfonic Acids

Eight norlignan glucosides, including two novel skeleton-rearranged compounds, sinenside A (1) and B (2), and six known compounds, crassifoside D (3), capituloside (4), a mixture of (1S,2R)-1-O-methylnyasicoside (5), (1R,2R)-1-O-methylisonyasicoside (6), and a mixture of (1S,2R)-1-O-methylcurculigine (7) and (1R,2R)-1-O-methylisocurculigine (8), were isolated from the rhizomes of Curculigo sinensis. Compounds 3-8 were isolated for the first time from this plant. Structures of the isolated compounds were established by spectroscopic analysis, including UV, IR, HRESI-MS, and 1D/2D NMR, and hydrolysis experiments. The free radical scavenging activity of the isolated compounds was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. All the isolated compounds showed strong radical scavenging activities.

Topics: Biphenyl Compounds; Carbohydrate Conformation; Curculigo; Free Radical Scavengers; Glucosides; Lignans; Models, Molecular; Picrates; Rhizome

To investigate the bioactive constituents in the stem of Piper wallichii.. Compounds were separated by column chromatography of silica gel, ODS-A and Sephadex LH-20. Their structures were elucidated based on spectral analysis. DPPH scavenging activity and AchE inhibitory activity were tested.. 10 compounds were isolated and their structures were identified as 3,4-methylenedioxy-benzoic acid (1), vanillic acid (2), benzoic acid (3), N-p-coumaroyltyramine (4), futoenone (5), futoquinol (6), isofutoquinol A (7), 4-hydroxy-3,5-dimethoxy-benzoic acid (8), futoamide (9), dihydropiperlonguminine (10).. Compounds 1-6 are isolated from P. wallichii for the first time. Vanillic acid (2) and 4-hydroxy-3,5-dimethoxy-benzoic acid (8) show scavenging activity against DPPH radical with ED50 at 224.33 microg/mL and 11.44 microg/mL, respectively. No compound shows inhibition activity against AchE.

Topics: Benzoates; Benzoic Acid; Biphenyl Compounds; Cholinesterase Inhibitors; Coumaric Acids; Free Radical Scavengers; Hydroxybenzoates; Lignans; Molecular Structure; Picrates; Piper; Plant Stems; Plants, Medicinal; Vanillic Acid

Two new compounds, (2S,3R)-methyl 7-hydroxy-2-(4-hydroxy-3-methoxy-phenyl)-3-(hydroxymethyl)-2,3-dihydrobenzofuran-5-carboxylate (1) and (4R,5S)-5-(3-hydroxy-2,6-dimethylphenyl)-4-isopropyldihydrofuran-2-one (2), tentatively named norcurlignan and limlactone, respectively, were isolated from Liriope muscari, together with the known compound (-)-pinoresinol (3). The structures of these compounds were elucidated and characterized on the basis of 1D NMR, 2D NMR, CD and MS data. The in vitro antioxidant activities of compounds 1-3 were assessed by the DPPH and ABTS scavenging methods.

Topics: Benzofurans; Benzothiazoles; Biphenyl Compounds; Chromatography, Gel; Free Radical Scavengers; Free Radicals; Furans; Lignans; Liriope Plant; Magnetic Resonance Spectroscopy; Medicine, Chinese Traditional; Molecular Conformation; Molecular Structure; Picrates; Sulfonic Acids

This work deals with antioxidant properties of pyrolytic lignins against two free radicals, 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid). Pyrolytic lignins produced by the thermal pyrolysis of the Etek lignin were extracted from the liquid pyrolysis product and fractionated using solvents of different polarities. The main functional groups linked to the lignin skeleton have been characterized by (1)H NMR and (19)F NMR upon acetylation and trifluoromethylation, respectively. Their radical scavenging activity against targeted free radicals was evaluated in vitro, and it was correlated to the content of studied functional groups. In contrast to the extracted Etek lignin, thermal pyrolysis produces lignin adducts that have higher scavenging efficacy than the nonthermally altered lignin and even higher than that of quercetin, a well-known phenolic antioxidant. The phenyl hydroxyl and methoxyl groups appear to be the main lignin structural factors contributing to the overall scavenging properties against the DPPH and ABTS free radicals. Also, these results show that there is no correlation between the content of aliphatic hydroxyl and carbonyl groups and the antioxidant activity.

Topics: Acetylation; Antioxidants; Benzothiazoles; Biphenyl Compounds; Free Radical Scavengers; Hot Temperature; Lignans; Magnetic Resonance Spectroscopy; Methylation; Picrates; Structure-Activity Relationship; Sulfonic Acids; Thiazoles

The chemical constituents of the stems and twigs of Lindera umbellata were investigated, and a new lignan derivative and four known compounds were isolated. The structure of the new compound was established as (2S,3S)-2,3-bis[(4-hydroxy-3,5-dimethoxyphenyl)methyl]-1,4-butanediol 1,4-diferulate on the basis of spectroscopic analysis and the result of alkaline methanolysis. The isolated compounds were evaluated for their scavenging effects on 1,1-diphenyl-2-picrylhydrazyl and O(2) (-) radicals.

Topics: Biphenyl Compounds; Free Radical Scavengers; Free Radicals; Lignans; Lindera; Oxygen; Peroxides; Picrates; Plant Stems

From the aqueous extract of the wood of Taxus yunnanensis, which showed cytochrome P450 3A4 (CYP3A4) inhibition, a new isoflavan [(3S,4R)-4'-hydroxy-6,3'-dimethoxyisoflavan-4-ol (1)], a new degraded lignan [2,3-bis(hydroxymethyl)-7-hydroxy-6-methoxy-1-tetralone (2)], and a new lignan [(7R)-7-hydroxytaxiresinol (3)] were isolated, together with nine known lignans. Among the isolates obtained, α-conidendrin (12) showed strong CYP3A4 inhibition with an IC(50) value of 0.2 μM.

Topics: Antineoplastic Agents, Phytogenic; Antioxidants; Biphenyl Compounds; Colletotrichum; Cytochrome P-450 CYP3A; Cytochrome P-450 CYP3A Inhibitors; Drug Screening Assays, Antitumor; Free Radical Scavengers; Furans; Hep G2 Cells; Humans; Isocoumarins; Isoflavones; Lignans; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Picrates; Taxus; Tetrahydronaphthalenes; Wood

Euryale ferox seed is consumed medicinally or for food in China. The present study revealed it to contain significant antioxidant activity, which may be associated with its medical applications as a proteinuria inhibitor of diabetic nephropathy. This study resulted in the identification of 3 new sesquineolignans, named euryalins A-C (1-3), and 16 known compounds, which were all first isolated from this plant apart from 5,7,4-trihydroxy-flavanone. The antioxidant potential of the partial isolates was evaluated using the DPPH radical scavenging assay and mesangial cellular assay. Compounds 2, rel-(2α,3β)-7-O-methylcedrusin (4), syringylglycerol-8-O-4-(sinapyl alcohol) ether (5), and (+)-syringaresinol (7) were found to be most active on DPPH assay, whereas compounds 2, 4, 7, (1R,2R,5R,6S)-2-(3,4-dimethoxyphenyl)-6-(3,4-dihydroxyphenyl)-3,7-dioxabicyclo[3.3.0]octane, and buddlenol E could significantly inhibit high glucose-stimulated reactive oxygen species production in mesangial cells. The results suggested that E. ferox seed could be considered as an excellent source of natural antioxidants and is useful in the prevention of diabetic nephropathy.

Topics: Animals; Antioxidants; Biphenyl Compounds; Cell Line; Diabetic Nephropathies; Glomerular Mesangium; Glucose; Lignans; Nymphaeaceae; Phytotherapy; Picrates; Plant Extracts; Proteinuria; Rats; Reactive Oxygen Species; Seeds

The antioxidative activity of secocyclolignanes was compared with that of the corresponding dibenzyl lignans for the first time. The radical scavenging activity of the secocyclolignanes was weaker than that of the corresponding dibenzyl lignans, the butane diol type showing the highest activity. The butane type of secocyclolignane exhibited the highest antioxidant activity of the unsaturated fatty acid.

Topics: Benzhydryl Compounds; Biphenyl Compounds; Free Radical Scavengers; Lignans; Picrates; Stereoisomerism; Substrate Specificity

A new neolignan, 3,4-dimethoxy-3',4'-methylenedioxy-2,9-epoxy-6,7-cyclo-1,8-neolign-11-en-5(5H)-one, which has been named (+)-kunstlerone (1), together with six known alkaloids: (+)-norboldine (2), (+)-N-methylisococlaurine (3), (+)-cassythicine (4), (+)-laurotetanine (5), (+)-boldine (6) and (-)-pallidine (7), were isolated from the leaves of Beilschmiedia kunstleri. The structures were established through various spectroscopic methods notably 1D- and 2D-NMR, UV, IR and LCMS-IT-TOF. (+)- Kunstlerone (1) showed a strong antioxidant activity, with an SC(50) of 20.0 µg/mL.

Topics: Alkaloids; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Chemistry, Pharmaceutical; Chromatography, Liquid; Free Radicals; Lauraceae; Lignans; Magnetic Resonance Spectroscopy; Malaysia; Mass Spectrometry; Models, Molecular; Picrates; Plant Leaves

Forsythia suspensa extract has been proved as a potential antioxidant in the recent years. The present study was undertaken to obtain the optimal antioxidant fraction in vitro and examine its antioxidative potential against diquat-induced oxidative stress in male Sprague Dawley rats in vivo. In vitro, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging experiment indicated that the CH2Cl2 fraction of F. suspensa (FSC) exerted the strongest scavenging activities; forsythoside A, forythialan A and phillygenin from it might be the major antioxidant constituents. In vivo, pretreatment of rats with different doses of FSC (25, 50 and 100 mg/kg bw) and vitamin C (100 mg/kg bw, positive control) for 15 days significantly lowered the tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6) in plasma compared to the negative control group. Also, FSC significantly increased the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and the levels of glutathione (GSH) in plasma, liver and kidney whereas it decreased the levels of malondialdehyde (MDA) in plasma and kidney. Moreover, the protective effect of FSC (100 mg/kg bw) was better than vitamin C. These results revealed that FSC exerted a protective effect against diquat-induced oxidative stress and is worthy of becoming a potential dietary antioxidant.

Topics: Animals; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Cytokines; Diquat; Forsythia; Free Radicals; Fruit; Glycosides; Herbicides; Indicators and Reagents; Kidney; Lignans; Liver; Male; Oxidative Stress; Oxidoreductases; Picrates; Rats; Rats, Sprague-Dawley

Four new oxygenated dibenzocyclooctadiene lignans, arisanschinins A-D ( 1- 4), and a new 1,4-bis(phenyl)-2,3-dimethylbutane lignan, arisanschinin E ( 5), together with 15 known compounds, were isolated from the EtOAc-soluble fraction of the aerial parts of SCHISANDRA ARISANENSIS Hay. The structures of 1- 5 were elucidated on the basis of extensive spectroscopic analyses, including 2D NMR (HMQC, HMBC, and NOESY) experiments. The configurations of the biphenyl and octadiene moieties were deduced from circular dichroism (CD) and NOESY spectra, respectively. Compound 1 showed significant inhibition of α-glucosidase IN VITRO. The radical-scavenging activities of these compounds were evaluated using DPPH.

Topics: Biphenyl Compounds; Cyclooctanes; Free Radical Scavengers; Lignans; Nuclear Magnetic Resonance, Biomolecular; Picrates; Plant Extracts; Schisandra

Two novel antioxidants, obtusilactone A (1) and (-)-sesamin (2) have been identified in Cinnamomum kotoense Kanehira. Both showed effective 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity compared with vitamin C, and reducing power compared with BHA. These results suggest that these constituents of C. kotoense act as natural antioxidants and play a potential role in cancer prevention.

Topics: Antioxidants; Biphenyl Compounds; Cinnamomum; Dioxoles; Lignans; Molecular Structure; Oxidation-Reduction; Picrates; Plant Leaves

To study the chemical constituents from Pachysandra terminalis and their antioxidant activity.. Chemical constituents were isolated by repeated column chromatography (silica gel, Toyopearl HW-40C and preparative HPLC). The structures of isolated compounds were elucidated on the basis of spectral data analysis. DPPH method was used to evaluate the free radical scavenging activity of the isolated compounds.. Six compounds were isolated and their structures were identified as follow: 2-Phenylethyl-beta-D-glucopyranoside (1), (+)Pinoresinol-4'-O-beta-D-glucopyranoside (2), Pinoresinol (3), cis-Syringin (4), 4-hydroxy-4-(3-oxo-l-butenyl)-3,5,5-trimethylcyclohex-2-en-l-one (5), 3alpha-hydroxy-5,6-epoxy-7-megastigmen-9-one (6). Compounds 2, 4, 5 showed obviously antioxidant activity, their DPPH free radical scavenging rates were 82.50%, 87.36%, and 84.56% on the concentration of 50 micromol/L, respectively.. Compounds 1-6 are isolated from this genus for the first time. Compounds 2, 4, and 5 showed significant antioxidant activities.

Topics: Antioxidants; Biphenyl Compounds; Chromatography, High Pressure Liquid; Free Radical Scavengers; Furans; Glucosides; Glycosides; Lignans; Magnetic Resonance Spectroscopy; Molecular Structure; Pachysandra; Phenylethyl Alcohol; Phenylpropionates; Picrates; Plant Extracts; Plants, Medicinal

A new lignan glucoside (1) was isolated from the stems of Callicarpa japonica Thunb. var. luxurians Rehd. (Verbenaceae), along with six known lignan glucosides and three known triterpenoids. The chemical structure of 1 was characterized as (+)-lyoniresinol 3 alpha-O-(6''-3,5-dimethoxy-4-hydroxybenzoyl)-beta-D-glucopyranoside on the basis of spectroscopic data. In addition, the radical-scavenging effect of four lignans on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Among the tested compounds, three compounds, including 1, showed almost the same scavenging activity as that of alpha-tocopherol.

Topics: Antioxidants; Biphenyl Compounds; Callicarpa; Free Radical Scavengers; Glucosides; Hydrazines; Lignans; Magnetic Resonance Spectroscopy; Molecular Structure; Picrates; Plant Extracts; Plant Stems; Triterpenes

Three new compounds, magnolianone (1), erythro-honokitriol (2), and threo-honokitriol (3), together with 14 known compounds, magnaldehyde (4), magnatriol B (5), randaiol (6), obovatol (7), magnolignan B (8a and 8b), magnolol, honokiol (9), p-hydroxylbenzaldehyde, coniferaldehyde, coniferol alcohol, syringaldehyde, syringaresinol, and acteoside, were isolated from the MeOH-soluble part of a water extract of the stem bark of Magnolia officinalis. Among these compounds, 2-8b were studied for anti-inflammatory and antioxidative activities. Compound 7 displayed more potent antioxidative potential than 9. Compounds 4-7 effectively inhibited LPS-induced NO production, whereas 5 and 6 were more potent than 9.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Biphenyl Compounds; Cyclohexanones; Lignans; Lipopolysaccharides; Magnolia; Mice; Microglia; Molecular Structure; Nitric Oxide; Picrates; Plant Bark; Plants, Medicinal; Taiwan

A new lignan rhamnoside, racemiside (1), has been isolated from the ethyl acetate-soluble fraction of Cotoneaster racemiflora, along with scopoletin (2), 7,8-dimethoxy-6-hydroxycoumarin (3), 3,3',4'-tri-O-methylellagic acid (4), and cereotagloperoxide (5), reported for the first time from this species. All of them showed profound antioxidative activities in the DPPH assay.

Topics: Antioxidants; Biphenyl Compounds; Glycosides; Lignans; Molecular Structure; Pakistan; Picrates; Plants, Medicinal; Rosaceae; Scopoletin

A new flavonol galloylrhamnoside, kaempferol 3-O-(2'',3''-di-O-galloyl)-alpha-L: -rhamnopyranoside, and a new lignan glycoside, hinokinin 7-O-beta-D: -glucopyranoside were isolated from the leaves of Koelreuteria henryi, along with 18 known compounds, including six flavonol glycosides (3-8), three lignans (9-11), four chlorophyll derivatives (12-15), two steroids (16, 17), and three aromatic compounds (18-20). The structures were determined on the basis of spectral analysis and chemical evidence. The scavenging effect of 1-8 and 20 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 5, 6, and 20 showed more potent activity than that of trolox.

Topics: Antioxidants; Biphenyl Compounds; Chromans; Dioxoles; Flavonols; Free Radical Scavengers; Glucosides; Glycosides; Kaempferols; Lignans; Medicine, Chinese Traditional; Picrates; Plant Leaves; Proanthocyanidins; Sapindaceae; Spectrum Analysis; Taiwan

Nine new lignans, chushizisins A-I (1-9), and three known lignans, threo-1-(4-hydroxy-3-methoxyphenyl)-2-{4-[(E)-3-hydroxy-1-propenyl]-2-methoxyphenoxy}-1,3-propanediol (10), erythro-1-(4-hydroxy-3-methoxyphenyl)-2-{4-[(E)-3-hydroxy-1-propenyl]-2-methoxyphenoxy}-1,3-propanediol (11), and 3-[2-(4- hydroxyphenyl)-3-hydroxymethyl-2,3-dihydro-1-benzofuran-5-yl]propan-1-ol (12), were isolated from the fruits of Broussonetia papyrifera. Their structures were elucidated using spectroscopic methods. Compounds 1, 5, 6, 8, 9, and 11 exhibited antioxidant activities against H(2)O(2)-induced impairment in PC12 cells, while compounds 1, 2, 4, 7, and 11 showed DPPH radical-scavenging activities with IC(50) values of 236.8, 156.3, 273.9, 281.1, and 60.9 microM, respectively.

Topics: Animals; Antioxidants; Biphenyl Compounds; Broussonetia; Drugs, Chinese Herbal; Fruit; Hydrogen Peroxide; Lignans; Molecular Structure; PC12 Cells; Picrates; Rats; Stereoisomerism

The fruits of Capsicum annuum were extracted using 80% aqueous MeOH, and fractionated using EtOAc and water. Repeated column chromatography using silica gel, octadecyl silica gel, and Sephadex LH-20 for the EtOAc fraction led to the isolation of a new lignan glycoside and a known one, icariside E(5). From the results of spectroscopic data, including EIMS, FABMS, UV, IR, (1)H and (13)C-NMR, DEPT, and 2D-NMR (COSY, HSQC, HMBC), the chemical structure of the new lignan glycoside was determined as (8R)-isodehydrodiconiferyl alcohol-4'-O-(6''-vanilloyl)-beta-D-glucopyranoside named vanilloylicariside E(5). All isolated compounds were tested for antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Icariside E(5) (2) and (8R)-Isodehydrodiconiferyl alcohol (3) exhibited a strong scavenging effect on DPPH (2: IC(50)=42.1 microM, 3: IC(50)=4.5 microM).

Topics: Antioxidants; Biphenyl Compounds; Capsicum; Free Radicals; Fruit; Lignans; Molecular Structure; Picrates

Schisandra propinqua (Wall.) Baill.(Schisandraceae) is widely used as a Chinese folk medicine. In this study, activity-guided fractionation of the ethanol extract from the stem of Schisandra propinqua led to the isolation of four extracts. Subsequently, a neolignan 4,4-di(4-hydroxy-3-methoxyphenly)-2,3-dimethylbutanol was isolated from the EtOAc part of the stem of Schisandra propinqua, the free radical scavenging activities of which were researched in vitro. The present work demonstrated that extracts and pure compound possessed scavenging activities to DPPH, superoxide anions and hydroxy radical, and could depress lipid peroxidation reaction induced by oxygen radical produced by the Fe2+/cysteine system in vitro. This suggests that the traditional application of Schisandra propinqua in China may be related to its antioxidant activities, and the EtOAc part of the stems of Schisandra propinqua can be utilized as an effective source of antioxidants.

Topics: Animals; Antioxidants; Biphenyl Compounds; Hydroxyl Radical; Lignans; Lipid Peroxidation; Male; Peroxides; Picrates; Plant Extracts; Rats; Rats, Wistar; Schisandra; Superoxides

A novel norlignan derivative, crassifogenin C (1), and a known compound, curcapital (2), were isolated from the ethanolic extract of the rhizomes of Curculigo crassifolia. Their structures were elucidated on the basis of spectroscopic evidence and comparisons with literature data. Curcapital (2) was isolated from this plant for the first time. The free radical scavenging activity of the isolated compounds along with crassifoside E (3) and crassifoside F (4), which were reported previously, was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. All compounds showed strong radical scavenging activity. The primary structure-activity relationship is also discussed.

Topics: Ascorbic Acid; Biphenyl Compounds; Curculigo; Free Radical Scavengers; Lignans; Magnetic Resonance Spectroscopy; Molecular Conformation; Picrates; Plant Roots; Spectrophotometry, Infrared; Spectrophotometry, Ultraviolet

Two new phenyldihydronaphthalene-type lignan glucosides, vitecannasides A (1) and B (2) were isolated from the fruit of Vitex cannabifolia Sieb. et. Zucc. (Verbenaceae) along with the six known lignan derivatives (3-8), four known iridoid glucosides (9-12), three known flavonoids (13-15), and one known phenylbutanone glucoside (16). Their chemical structures were determined on the basis of spectroscopic data as well as chemical evidence. The scavenging effect of 1, 2, and 11-16 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 2, 14, and 15 exhibited stronger activity than that of L: -cysteine. Especially, 14 and 15 showed more potent activity than that of alpha-tocopherol.

Topics: alpha-Tocopherol; Biphenyl Compounds; Cysteine; Flavonoids; Free Radical Scavengers; Fruit; Glucosides; Iridoids; Lignans; Magnetic Resonance Spectroscopy; Molecular Structure; Picrates; Vitex

Dibenzo[a,c]cyclooctadiene lignans of Schisandra chinensis Baill are well known because of their hepatoprotective activity, antioxidant activity, and anticancer effect. For the isolation of the dibenzo[a,c]cyclooctadiene lignans of Schisandra chinensis Baill two extraction methods were used: modified-ultrasonic extraction and supercritical fluid extraction. A specific and fast analytical method for structure identification is established for quality control because structure elucidation could be accomplished by means of liquid chromatography-mass spectrometry (LC-MS) technologies. The separation and identification of the compounds were completed by: (i) a water-acetonitrile gradient system using a C18 reversed-phase column; (ii) UV detection at 225 nm; (iii) MS/MS experiments with electrospray ionization interface (ESI) ion trap mass spectrometry in the positive mode. Normalized collision energy was used to obtain fragment ions of structural relevance in the LC-MS/MS. These results provided a reliable LC-MS/MS method for the determination of the dibenzo[a,c]cyclooctadiene lignans from Schisandra chinensis Baill. Finally, we also detected 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging effects (%) of the modified-ultrasonic and supercritical fluid extracts of Schisandra chinensis Baill compared with 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox). The antioxidant activities of the modified-ultrasonic and supercritical fluid extracts were lower than that of trolox.

Topics: Antioxidants; Biphenyl Compounds; Carbon Dioxide; Chromans; Chromatography, High Pressure Liquid; Chromatography, Liquid; Chromatography, Supercritical Fluid; Cyclooctanes; Free Radical Scavengers; Free Radicals; Hydrazines; Lignans; Mass Spectrometry; Picrates; Schisandra; Spectrometry, Mass, Electrospray Ionization; Ultrasonics

Six new mixed lignan-neolignans and 20 known compounds were isolated from the whole plant of Tarenna attenuata. By analysis of physical and spectroscopic data, the structures of the new compounds were elucidated as (1R,5R,6R)-6-{4-O-[2-(1-(4-hydroxy-3-methoxyphenyl))glycerol]-3,5-dimethoxyphenyl}-3,7-dioxabicyclo[3.3.0]octan-2-one (1), 5' '-methoxyhedyotisol A (2), 4' '-O-(8-guaiacylglycerol)buddlenol A (3), 5' '-methoxy-4' '-O-(8-guaiacylglycerol)buddlenol A (4), 4,6-dimethoxy-5-hydroxy-3-hydroxymethyl-2-(3,4,5-trimethoxyphenyl)-2,3-dihydrobenzofuran (5), and 7-O-ethylguaiacylglycerol (6). Compounds 1, 5, 6, and 8 showed potent antioxidant activities against H2O2-induced impairment in PC12 cells, and compounds 1, 2, 5, and 7 scavenged DPPH radical strongly with IC50 values of 72, 87, 45, and 55 microM, respectively.

Topics: Analgesics; Animals; Antioxidants; Biphenyl Compounds; Drugs, Chinese Herbal; Free Radical Scavengers; Hydrogen Peroxide; Inhibitory Concentration 50; Lignans; PC12 Cells; Picrates; Plants, Medicinal; Rats; Rubiaceae

The antioxidant (DPPH radical and superoxide anion scavenging activities), and cytotoxic (in tumor, Jurkat, PC-3, Colon 205, HepG2, and normal PBMCs cells) activities of 16 plant phenolic or related compounds were evaluated in vitro. Different categories compounds corresponding to 10 flavonoids, three lignans, two phenolic acids, and a catechin showed significant mean differences in antioxidant and cytotoxic activities. Particularly, the flavonols, quercetin (3) and tiliroside (11) possess significant antioxidant activity, as well as cytotoxic activity against Jurkat; and Jurkat and HepG2 cells, respectively. In contrast, the flavanone, 5,7-dimethoxy-3',4'-methylenedioxyflavanone (7), and homoisoflavonoid, isobonducellin (10) shown to have no significant antioxidant activity, but exhibited potent cytotoxic activity in Jurkat and HepG2 cells, while moderate growth inhibition against Colon205 cells. Interestingly, none of these derivatives shown to have toxicity toward normal peripheral blood mononuclear cells, over the concentration range tested (5-200 microM). Cytotoxic activities of some natural flavonoids identified in the medicinal plants were evaluated for the first time.

Topics: Antineoplastic Agents; Antioxidants; Biphenyl Compounds; Catechin; Cell Line, Tumor; Dose-Response Relationship, Drug; Flavonoids; Free Radical Scavengers; Humans; Hydrazines; Hydroxybenzoates; Lignans; Phenols; Picrates; Superoxides

Eight new oxygenated lignans, kadsuphilols A-H (1-8), were isolated from the leaves and stems of Kadsura philippinensis. Four of the isolated lignans (1-4) possess the normal C18-dibenzocyclooctadiene skeleton, while the other four lignans (5-8) are C19-homolignans possessing a substituted cyclohexadienone ring with a spiro-benzofuranoid moiety. The structures of the isolated metabolites were elucidated through spectroscopic analyses, including 2D NMR experiments. Compounds 1 and 4 are the first report of an R-biphenyl configuration with a beta-oxygenated substituent at the C-9 position. The in vitro radical-scavenging activities of these compounds using DPPH were tested and evaluated. Compound 3 exhibited more potent activity than vitamins C and E.

Topics: Ascorbic Acid; Biphenyl Compounds; Free Radical Scavengers; Kadsura; Lignans; Molecular Structure; Picrates; Plant Leaves; Plant Stems; Plants, Medicinal; Taiwan; Vitamin E

The flaxseed lignan secoisolariciresinol diglucoside (SDG) and mammalian lignans enterodiol (ED) and enterolactone (EL) were previously shown to be effective antioxidants against DNA damage and lipid peroxidation. Others reported inhibition of activated cell chemiluminescence by supra-physiological concentrations of secoisolariciresinol (SECO), ED and EL. Thus, we evaluated the antioxidant efficacy of potential physiological concentrations of SDG, SECO, ED and EL against 1,1-diphenyl-2-picrylhydrazyl (DPPH()), and 2,2'-azo-bis(2-amidinopropane) dihydrochloride (AAPH)-initiated peroxyl radical plasmid DNA damage and phosphatidylcholine liposome lipid peroxidation. SDG and SECO were effective (p<0.01) antioxidants against DPPH() at 25-200muM; whereas, ED and EL were inactive. Efficacy of lignans and controls against AAPH peroxyl radical-induced DNA damage was: SDG>SECO=17alpha-estradiol>ED=EL>genistein>daidzein. Lignan efficacy against AAPH-induced liposome lipid peroxidation was: SDG>SECO=ED=EL. Plant lignan antioxidant activity was attributed to the 3-methoxy-4-hydroxyl substituents of SDG and SECO, versus the meta mono-phenol structures of ED and EL. Benzylic hydrogen abstraction and potential resonance stabilization of phenoxyl radicals in an aqueous environment likely contributed to the antioxidant activity of the mammalian lignans. These represent likely extra- and intracellular antioxidant activities of flax-derived lignans at concentrations potentially achievable in vivo.

Topics: 4-Butyrolactone; Animals; Biphenyl Compounds; Butylene Glycols; Flax; Free Radical Scavengers; Glucosides; Hydrazines; Lignans; Liposomes; Mammals; Molecular Structure; Picrates; Seeds

A new lignan, actaealactone (1), and a new phenylpropanoid ester derivative, cimicifugic acid G (2), together with 15 known polyphenols, protocatechuic acid, protocatechualdehyde, p-coumaric acid, caffeic acid, methyl caffeate, ferulic acid, ferulate-1-methyl ester, isoferulic acid, 1-isoferuloyl-beta-d-glucopyranoside, fukinolic acid, and cimicifugic acids A, B, and D-F, were isolated from an extract of the rhizomes and roots of black cohosh (Actaea racemosa). The structures of the new compounds were determined on the basis of NMR spectroscopic analysis. Compounds 1 and 2 displayed antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical assay with IC(50) values of 26 and 37 microM, respectively. Other antioxidants identified from A. racemosa include cimicifugic acid A (3), cimicifugic acid B (4), and fukinolic acid (5). Compounds 1 and 2 also exhibited a small stimulating effect on the growth of MCF-7 breast cancer cell proliferation 1.24-fold (14 microM) and 1.14-fold (10 microM), respectively, compared to untreated cells.

Topics: Biphenyl Compounds; Breast Neoplasms; Caffeic Acids; Cimicifuga; Female; Flavonoids; Free Radical Scavengers; Humans; Lignans; Molecular Structure; Phenols; Phenylacetates; Picrates; Plant Roots; Plants, Medicinal; Polyphenols; Rhizome; Tumor Cells, Cultured

Four new C18 dibenzocyclooctadiene lignans, kadsuphilins A (1) and B (3), 6-epi-gomisin (2), and 1-demethylkadsuphilin A (4), along with eight known related metabolites, were isolated from an EtOAc fraction of an alcoholic extract of the aerial parts of Kadsura philippinensis growing in Taiwan. The structures of 1-4 were elucidated on the basis of spectroscopic analyses, including 2D NMR (HMQC, HMBC, and NOESY) experiments, and by comparison of their spectroscopic data with those of related metabolites. The configurations of the biphenyl and cyclooctadiene moieties were deduced from circular dichroism (CD) and NOESY NMR spectra, respectively. Some of the compounds showed radical-scavenging activity in a DPPH-HPLC method.

Topics: Biphenyl Compounds; Cyclooctanes; Free Radical Scavengers; Kadsura; Lignans; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Picrates; Plants, Medicinal; Taiwan

To evaluate the antioxidant capacity and quality of traditional Chinese medicines using TLC-bioautography.. Two chromatograms of each crude drug sample were obtained, after developing, by spraying with 1,1-diphenyl-2-picrylhydrazyl (DPPH) solution in ethanol and classical stained reagents, separately. The images sprayed with DPPH solution were captured under light after the plates were heated at 40 degrees C for 30 min, and scanned using video scan software to get peak areas of active compounds.. Total peak areas of the spots on TLC were calculated to evaluate the antioxidant capacity of the tested crude drugs from different habitats and sources. The results indicated that Radix Linderae cultivated in Tiantai (Zhejiang province), Cortex Magnoliae Officinalis cultivated in Liangshan (Sichuan province), and Fructus Perillae acquired in Shanghai have the highest scavenging properties towards DPPH in their respective TLC-autographic assays. Norisoboldine, magnolol and honokiol, luteolin, apigenin and an unknown compound "U" proved to be the major antioxidant components in the corresponding crude drugs as they contribute the dominating peak areas to the total ones.. TLC-bioautography can not only be used for screening of the components with antioxidant potency but also for the purpose of quality evaluation of traditional Chinese medicines at the same time, and the method proved to be selective, simple and reproducible.

Topics: Alkaloids; Antioxidants; Biphenyl Compounds; China; Chromatography, Thin Layer; Drugs, Chinese Herbal; Hydrazines; Lignans; Lindera; Luteolin; Magnolia; Perilla; Picrates; Plants, Medicinal; Quality Control; Reproducibility of Results

Propionibacterium acnes, an anaerobic pathogen, plays an important role in the pathogenesis of acne and seems to initiate the inflammatory process by producing proinflammatory cytokines. In order to demonstrate the anti-inflammatory effects and action mechanisms of magnolol and honokiol, several methods were employed. Through DPPH and SOD activity assays, we found that although both magnolol and honokiol have antioxidant activities, honokiol has relatively stronger antioxidant activities than magnolol {[for DPPH assay, % of DPPH bleaching of magnolol and honokiol (500 microM magnolol: 19.8%; 500 microM honokiol: 67.3%)]; [for SOD assay, SOD activity (200 microM magnolol: 53.4%; 200 microM honokiol: 64.3%)]}. Moreover, the production of interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-alpha) induced by P. acnes in THP-1 cells, a human monocytic cell line, was reduced by magnolol and honokiol {[for IL-8 (10 microM magnolol: 42.7% inhibition; 10 microM honokiol: 51.4% inhibition)]; [for TNF-alpha (10 microM magnolol: 20.3% inhibition; 10 microM honokiol: 39.0% inhibition)]}. Cyclooxygenase-2 (Cox-2) activity was also suppressed by them [(15 microM magnolol: 45.8% inhibition), (15 microM honokiol: 66.3% inhibition)]. Using a nuclear factor-kappaB (NF-kappaB) luciferase reporter assay system and Western analysis, we identified that magnolol and honokiol exert their anti-inflammatory effects by inhibiting the NF-kappaB element, which exists in Cox-2, IL-8, and TNF-alpha promoters [(15 microM magnolol: 44.8% inhibition), (15 microM honokiol: 42.3% inhibition)]. Of particular note is that magnolol and honokiol operate downstream of the MEKK-1 molecule. Together with their previously known antibacterial activity against P. acnes and based on these results, we suggest that magnolol and honokiol may be introduced as possible acne-mitigating agents.

Topics: Anti-Bacterial Agents; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Biphenyl Compounds; Cytokines; Humans; Interleukin-8; Lignans; Magnolia; MAP Kinase Kinase Kinase 1; Microbial Sensitivity Tests; Monocytes; NF-kappa B; Phytotherapy; Picrates; Plant Extracts; Propionibacterium acnes; Superoxide Dismutase; Tumor Necrosis Factor-alpha

In our investigation of in vitro anti-allergic screening of medicinal herbal extracts, the ethyl acetate extract of the root of Wikstroemia indica was observed to inhibit nitric oxide (NO) production in a lipopolysaccharide (LPS) and recombinant mouse interferon-gamma (IFN-gamma) activated murine macrophage-like cell line, RAW 264.7. Fractionation of the active extract led to the isolation of two new lignan dimer bis-5,5-nortrachelogenin (1) and bis-5,5'-nortrachelogenin (2), and three known lignans. Compound 1 and lirioresinol B (5) inhibited NO production with IC50 values at 48.6 and 53.5 microM, respectively. Compound 5 also showed free radical scavenging effect on 1,1-diphenyl-2-picrylhydrazil (DPPH) at IC50 values at 19.5 microM.

Topics: Animals; Biphenyl Compounds; Carbon Isotopes; Cell Line; Drug Evaluation, Preclinical; Free Radical Scavengers; Interferon-gamma; Lignans; Lipopolysaccharides; Macrophages; Magnetic Resonance Spectroscopy; Mice; Molecular Structure; Nitric Oxide; Picrates; Plant Extracts; Plant Roots; Protons; Recombinant Proteins; Reference Standards; Wikstroemia

The antioxidant activities of Acanthopanax senticosus stems were evaluated in CCl4-intoxicated rats. The n-butanol fraction from the water extract of the stems, when pretreated orally at 200 mg/kg/day for 7 consecutive days in rats, was demonstrated to exhibit significant increases in antioxidant enzyme activities such as hepatic cytosolic superoxide dismutase, catalase and glutathione peroxidase by 30.31, 19.82 and 155%, respectively. The n-butanol fraction whereas showed a significant inhibition of serum GPT activity (65.79% inhibition) elevated with hepatic damage induced by CCl4-intoxication. Eleutheroside B, a lignan component, isolated from the n-butanol fraction was found to cause a moderate free radical scavenging effect on DPPH, its scavenging potency as indicated in IC50 value, being 58.5 microM. These results suggested that the stems of A. senticosus possess not only antioxidant but also hepatoprotective activities.

Topics: Administration, Oral; Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Biphenyl Compounds; Butanols; Carbon Tetrachloride Poisoning; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Eleutherococcus; Free Radical Scavengers; Glucosides; Hepatocytes; Indicators and Reagents; Lignans; Male; Phenylpropionates; Picrates; Plant Extracts; Plant Stems; Rats; Rats, Sprague-Dawley; Silymarin; Solubility; Water

The free radical scavenging capacity (RSC) of antioxidants from sesame cake extract was studied using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)()) on a kinetic model. Pure lignans and lignan glycosides isolated from methanolic extract by preparative HPLC were used in the study. To understand the kinetic behavior better and to determine the RSC of sesame antioxidants, the second-order rate constant (k(2)) was calculated for the quenching reaction with [DPPH(*)] radical. The k(2) values of the sesame antioxidants were compared with those of butylated hydroxytoluene and alpha-tocopherol. The k(2) values for sesamol, sesamol dimer, sesamin, sesamolin, sesaminol triglucoside, and sesaminol diglucoside were 4.00 x 10(-)(5), 0.50 x 10(-)(5), 0.36 x 10(-)(5), 0.13 x 10(-)(5), 0.33 x 10(-)(5), and 0.08 x 10(-)(5) microM(-)(1) s(-)(1), respectively.

Topics: Antioxidants; Benzodioxoles; Biphenyl Compounds; Dioxoles; Free Radical Scavengers; Free Radicals; Furans; Kinetics; Lignans; Phenols; Picrates; Plant Extracts; Sesamum

From the stem of Strychnos vanprukii, two new lignan glucosides, vanprukoside (1) and strychnoside (2), were isolated together with the known lignan glucoside, (+)-lyoniresinol-3 alpha-O-beta-glucopyranoside (3). The structures of these compounds were elucidated on the basis of their spectroscopic data. All three compounds exhibited antioxidant activity.

Topics: Antioxidants; Biphenyl Compounds; Glucosides; Humans; Lignans; Phytotherapy; Picrates; Plant Extracts; Plant Stems; Strychnos

A new furofuran lignan, styraxlignolide B (1), and four new dibenzyl-gamma-butyrolactone lignans, styraxlignolides C-F (2-5), were isolated from the EtOAc-soluble fraction of stem bark of Styrax japonica. Known compounds, taraxerol (6), syringin (7), and (-)-pinoresinol glucoside (8), were also obtained. The structures of styraxligonolides B-F were determined as 2alpha-(4'-hydroxy-3'-methoxyphenyl)-6alpha-(3' ',4' '-methylenedioxyphenyl)-8-oxo-3,7-dioxabicyclo[3.3.0]octane 4'-O-(beta-D-glucopyranoside) (1), (2S,3S)-2alpha-(3' '-hydroxy-4' '-methoxybenzyl)-3beta-(4'-hydroxy-3'-methoxybenzyl)-gamma-butyrolactone 4'-O-(beta-D-glucopyranoside) (2), (2S,3S)-2alpha-(4' '-hydroxy-3' '-methoxybenzyl)-3beta-(4'-hydroxy-3'-methoxybenzyl)-gamma-butyrolactone 4'-O-(beta-D-glucopyranoside) (3), (2S,3S)-2alpha-(4' '-hydroxy-3' '-methoxybenzyl)-3beta-(4'-hydroxy-3'-methoxybenzyl)-gamma-butyrolactone 4' '-O-(beta-D-glucopyranoside) (4), and (2S,3S)-2alpha-(3' ',4' '-dimethoxybenzyl)-3beta-(4'-hydroxy-3'-methoxybenzyl)-gamma-butyrolactone 4'-O-(beta-D-glucopyranoside) (5) by spectroscopic means including 2D NMR. Compounds 1-8 were tested in vitro for antioxidant activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Styraxlignolide C (2), styraxlignolide D (3), styraxlignolide E (4), and (-)-pinoresinol glucoside (8) exhibited weak radical-scavenging activity in the DPPH assay, with IC50 values of 380, 278, 194, and 260 microM, respectively.

Topics: 4-Butyrolactone; Antioxidants; Biphenyl Compounds; Furans; Glucosides; Glycosides; Korea; Lignans; Molecular Structure; Oleanolic Acid; Phenylpropionates; Picrates; Plant Bark; Plants, Medicinal; Stereoisomerism; Styrax

A new phenyldihydronaphthalene-type lignan, vitedoin A (1), a new phenylnaphthalene-type lignan alkaloid, vitedoamine A (2), and a new trinorlabdane-type diterpene, vitedoin B (3), were isolated from the seeds of Vitex negundo along with five known lignan derivatives (4-8). Their chemical structures were determined mainly on the basis of NMR and MS data. Compounds 1, 2, and 4-7 showed stronger antioxidative activity than alpha-tocopherol using the ferric thiocyanate method. Compounds 1, 2, and 4-7 showed higher radical-scavenging effect on the stable free radical, 1,1-diphenyl-2-picrylhydrazyl, than L-cysteine.

Topics: alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Cysteine; Diterpenes; Drugs, Chinese Herbal; Lignans; Molecular Structure; Naphthalenes; Nuclear Magnetic Resonance, Biomolecular; Picrates; Plants, Medicinal; Seeds; Vitex

The aim of this study was to evaluate the cytoprotective effects upon primary human hepatocytes of silymarin extract and its main flavonolignans following exposure to the cytotoxic actions of model toxins. The conditions for the hepatocyte intoxication were optimised for allyl alcohol, carbon tetrachloride, D-galactosamine and paracetamol. Silymarin extract, silychristin and silydianin did not exert cytotoxicity (10-100 microM), whereas silybin and isosilybin at higher concentrations and after longer incubation periods were cytotoxic. All main flavonolignans of silymarin tested displayed concentration-dependent cytoprotection against the toxic effects of both allyl alcohol and carbon tetrachloride but neither paracetamol nor galactosamine. The best protection was achieved by silydianin and silychristin and to a lesser degree by silymarin, while silybin and isosilybin were less effective. It is concluded that these differing outcomes result from the varying abilities of the Silybum marianum substances tested to stabilize the cell membrane, exert antioxidant properties and exhibit intrinsic toxicity.

Topics: Acetaminophen; Analgesics, Non-Narcotic; Antioxidants; Asteraceae; Biphenyl Compounds; Cell Separation; Cell Survival; Cells, Cultured; Flavonoids; Free Radical Scavengers; Galactosamine; Hepatocytes; Humans; L-Lactate Dehydrogenase; Lignans; Picrates; Plant Extracts; Propanols; Protein Biosynthesis; tert-Butylhydroperoxide; Toxins, Biological

Sesamin, a major lignan in sesame oil, is known to have many biological activities, especially protective effects against oxidative damage in the liver. As sesamin itself has no antioxidative properties in vitro, to elucidate the mechanism of its antioxidative effects, the reaction products of sesamin in rat liver homogenate were analyzed. The methylenedioxyphenyl moiety in the structure of sesamin was shown to be changed into a dihydrophenyl (catechol) moiety. The enzymatic reaction products in vitro were identified as (1R,2S,5R,6S)-6-(3,4-dihydroxyphenyl)-2-(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo[3,3,0]octane and (1R,2S,5R,6S)-2,6-bis(3,4-dihydroxyphenyl)-3,7-dioxabicyclo[3,3,0]octane, which showed strong radical scavenging activities; the latter was a novel compound. The same metabolites were found as glucuronic acid and/or sulfic acid conjugates in substantial amounts in rat bile after oral administration of sesamin. It is suggested that sesamin is a prodrug and the metabolites containing the catechol moieties in their structures are responsible for the protective effects of sesamin against oxidative damage in the liver.

Topics: Animals; Antioxidants; Bile; Biphenyl Compounds; Chromatography, High Pressure Liquid; Dioxoles; Free Radical Scavengers; Hydroxyl Radical; Lignans; Lipid Peroxidation; Liver; Magnetic Resonance Spectroscopy; Male; Picrates; Rats; Rats, Wistar; Spectrometry, Mass, Electrospray Ionization

Antioxidant activity of Pinus densiflora Sieb. et Zucc. (Pinaceae) was evaluated for potential to inhibit hydroxyl radicals, inhibit total reactive oxygen species generation in kidney homogenates using 2',7'-dichlorodihydro fluorescein diacetate (DCHF-DA) and scavenge authentic peroxynitrites. The methanolic extract of P. densiflora showed strong antioxidant activity in the tested model systems and thus fractionated with several solvents. The antioxidant activity potential of the individual fraction was in the order of ethyl acetate > n-butanol > water > dichloromethane fraction. The ethyl acetate soluble fraction exhibiting strong antioxidant activity was further puri fi ed by repeated silica gel and Sephadex LH-20 column chromatographies. An active lignan (+)-isolarisiresinol xylopyranoside, as well as two active flavonoids [kaempferol 3-O-beta-galactopyranoside and its 6"-acetyl derivative], were isolated.

Topics: Antioxidants; Biphenyl Compounds; Free Radical Scavengers; Humans; Hydroxyl Radical; Kidney; Lignans; Peroxynitrous Acid; Phytotherapy; Picrates; Pinus; Plant Extracts; Plant Structures; Reactive Oxygen Species

We have investigated the developdment of potential antioxidants based on magnolol, a naturally occurring biphenolic obtained from the bark of Magnolia officinalis. A series of aminomethylated derivatives of magnolol were synthesized under the aromatic Mannich reaction. In-vitro testing for diphenyl-p-picrylhydrazyl (DPPH) scavenging and chemiluminescence assays in whole cell models revealed that the pyrrolidyl-containing magnolols (2b (5,5'-diallyl-3-(pyrrolidin-1-ylmethyl)-biphenyl-2,2'-diol), 3a (5,5'-diallyl-3,3'-bis-(pyrrolidin-1-ylmethyl)-biphenyl-2,2'-diol) and 4c (5,5'-diallyl-3-(morphorin-4-ylmethyl)-3'-(pyrrolidin-1-ylmethyl)-biphenyl-2,2'-diol)) displayed promising free radical scavenging effects as compared with magnolol. The results from compound 4c indicated that the naturally occurring component was suitable to be a lead compound toward promising antioxidants.

Topics: Biphenyl Compounds; Free Radical Scavengers; Hydrazines; Lignans; Luminescent Measurements; Magnolia; Picrates; Plant Bark; Plant Oils