ascorbic-acid and salvin

The antiradical power, at equal concentrations of active principles, of the following antioxidants were studied using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) assay: butylated-hydroxyanisole, butylated-hydroxytoluene, tert-butylhydroquinone, ascorbyl palmitate, tocopherol, grape seed extract, olive extract and five rosemary extracts with different concentrations of carnosic acid (CA) and carnosol (COL). The reaction kinetics of DPPH scavenging activity in each studied substance identified significant variations in the time needed to reach the steady state. Rosemary extracts were seen to be more effective than the other compounds. CA had higher antioxidant activity than COL, although COL seemed to react faster with DPPH. The relevance of the CA/COL ratio for the antioxidant activity of rosemary extracts was also analysed. The presence of COL in rosemary extracts increased the antioxidant activity with an optimal CA/COL ratio of 2.5-3.0. Olive extract and grape seed extract seem to be very promising additives for use as technological antioxidants.

Topics: Abietanes; Antioxidants; Ascorbic Acid; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Food Additives; Plant Extracts; Rosmarinus; Tocopherols

Biosynthesis of carnosic acid (CA), one of the most industrially valuable medicinal compounds present in rosemary (Rosmarinus officinalis L.) leaves, is affected by various plant stressors. In this study, effects of silver nanoparticle (AgNP) treatment on the secondary metabolism and CA production of rosemary plants were investigated. AgNP of 0, 25, 50, 100, and 200 ppm were utilized on hydroponically grown plants using foliar spray. Efficient absorbance and translocation of AgNPs to the plant roots were confirmed by XRF (X-ray fluorescence) analysis. The fluctuations of important antioxidant compounds such as CA content, phenolics, flavonoids, and acid ascorbic were analyzed and their correlations evaluated. Results revealed that application of 200 ppm AgNPs for 12 days increased CA level more than 11%, as compared to the control plants. Furthermore, significant positive correlations were observed between total flavonoids and CA content under AgNP treatment, suggesting that AgNP acted as an elicitor and triggered the enhancement of CA accumulation effectively. These data suggest that concentration-dependent AgNP may be used to boost antioxidant activity and phytochemical contents of other medicinal plants.

Topics: Abietanes; Antioxidants; Ascorbic Acid; Flavonoids; Iran; Metal Nanoparticles; Phenols; Phytochemicals; Plant Extracts; Plant Leaves; Plant Roots; Rosmarinus; Silver

The oxidative stability of liver pâté was investigated in relation to different doses of rosemary extract (RE) and sodium nitrite. Colour stability, lipid oxidation (TBARS) and concentrations of ascorbic acid, α-tocopherol, carnosic acid and nitrite were measured on the batters before cooking and on the cooked liver pâté before and after exposure to light and air for 48 h at 4°C. Results showed that the use of RE significantly reduced lipid oxidation, whereas it had no effect on colour stability. Ascorbic acid and nitrite concentrations were significantly higher and lower respectively when RE was added. RE dose-dependently increased the concentration of carnosic acid. Lower sodium nitrite doses resulted in significantly lower nitrite concentrations and slightly lower TBARS values. It was concluded that in liver pâté sodium nitrite levels may be lowered to 80 mg/kg without negatively affecting colour and lipid stability and that the use of RE may help in maintaining lipid stability.

Topics: Abietanes; alpha-Tocopherol; Animals; Antioxidants; Ascorbic Acid; Color; Cooking; Dose-Response Relationship, Drug; Lipid Metabolism; Meat Products; Plant Extracts; Rosmarinus; Sodium Nitrite; Swine; Thiobarbituric Acid Reactive Substances

During the microencapsulation process, the fish oil undergoes multiple changes in its physical properties such as bulkiness and dispersibility in aqueous phase and dry matrix. Autoxidation already occurred in the first stages of the microencapsulation process itself during emulsification and spray-drying. An efficient stabilization was achieved using a ternary combination of lipophilic antioxidants, synergistic compounds and a trace metal chelator, e.g. a combination of tocopherols, rich in the δ-derivative and low in the α-derivative, with ascorbyl palmitate and lecithin. Trace metal chelation by, e.g. Citrem or lecithin in combination with ascorbyl palmitate proved to be of particular importance in the emulsion, but not during the storage of the microencapsulated oil. In the microencapsulated oil, the addition of rosemary extract rich in carnosic acid to ternary blends of tocopherols, ascorbyl palmitate and lecithin or Citrem significantly retarded autoxidation.

Topics: Abietanes; Aldehydes; Antioxidants; Ascorbic Acid; Chelating Agents; Drug Compounding; Emulsions; Fatty Acids, Unsaturated; Fish Oils; Food Handling; Hydrogen Peroxide; Lecithins; Oils, Volatile; Oxidation-Reduction; Plant Extracts; Rosmarinus; Tocopherols

The aim of this study was to evaluate the antioxidant substances present in the human diet with an antimutagenic protective capacity against genotoxic damage induced by exposure to X-rays in an attempt to reduce biological damage to as low a level as reasonably possible.. Ten compounds were assessed using the lymphocyte cytokinesis-block micronucleus (MN) cytome test. The compounds studied were added to human blood at 25 μM 5 min before exposure to irradiation by 2 Gy of X-rays.. The protective capacity of the antioxidant substances assessed was from highest to lowest according to the frequency of the MN generated by X-ray exposure: rosmarinic acid = carnosic acid = δ-tocopherol = l-acid ascorbic = apigenin = amifostine (P < 0.001) > green tea extract = diosmine = rutin = dimetylsulfoxide (P < 0.05) > irradiated control. The reduction in genotoxic damage with the radiation doses administered reached 58%, which represents a significant reduction in X-ray-induced chromosomal damage (P < 0.001). This degree of protection is greater than that obtained with amifostine, a radioprotective compound used in radiotherapy and which is characterised by its high toxicity.. Several antioxidant substances, common components of the human diet and lacking toxicity, offer protection from the biological harm induced by ionizing radiation. Administering these protective substances to patients before radiological exploration should be considered, even in the case of small radiation doses and regardless of the biological damage expected.

Topics: Abietanes; Amifostine; Analysis of Variance; Antimutagenic Agents; Antioxidants; Apigenin; Ascorbic Acid; Catechin; Cells, Cultured; Cinnamates; Cytokinesis; Depsides; Diet; Diosmin; DNA Damage; Female; Humans; Lymphocytes; Micronucleus Tests; Plant Extracts; Radiation-Protective Agents; Radiometry; Rosmarinic Acid; Rutin; Tocopherols; X-Rays

To assess antioxidative protection by carnosic acid (CA) in combination with that of other low-molecular weight (M(r)) antioxidants (alpha-tocopherol [alpha-T] and ascorbate [Asc]) in chloroplasts, we measured endogenous concentrations of these antioxidants, their redox states, and other indicators of oxidative stress in chloroplasts of three Labiatae species, differing in their CA contents, exposed to drought stress in the field. Damage to the photosynthetic apparatus was observed neither in CA-containing species (rosemary [Rosmarinus officinalis]) and sage [Salvia officinalis]) nor in CA-free species (lemon balm [Melissa officinalis]) at relative leaf water contents between 86% and 58%, as indicated by constant maximum efficiency of photosystem II photochemistry ratios and malondialdehyde levels in chloroplasts. The three species showed significant increases in alpha-T, a shift of the redox state of alpha-T toward its reduced state, and increased Asc levels in chloroplasts under stress. Lemon balm showed the highest increases in alpha-T and Asc in chloroplasts under stress, which might compensate for the lack of CA. Besides, whereas in rosemary and sage, the redox state of CA was shifted toward its oxidized state and the redox state of Asc was kept constant, lemon balm displayed a shift of the redox state of Asc toward its oxidized state under stress. In vitro experiments showed that both CA and Asc protect alpha-T and photosynthetic membranes against oxidative damage. These results are consistent with the contention that CA, in combination with other low-M(r) antioxidants, helps to prevent oxidative damage in chloroplasts of water-stressed plants, and they show functional interdependence among different low-M(r) antioxidants in chloroplasts.

Topics: Abietanes; alpha-Tocopherol; Ascorbic Acid; Chloroplasts; Disasters; Diterpenes; Lamiaceae; Osmotic Pressure; Oxidation-Reduction; Plant Extracts; Plant Leaves; Species Specificity; Water

Preparative-scale incubations with Nocardia sp. NRRL 5646 were conducted to produce new derivatives of the abietane diterpene chemoprotectant and antioxidant carnosic acid (1). Reductive biotransformation of the C-20 carboxylic acid functional group followed by biological methylation at the C-11 phenol afforded 4. Oxidative cyclization of 1 to carnosol 5 followed by dihydroxylation at the isopropyl moiety afforded 6. Metabolites 4 and 6 are new carnosic acid derivatives whose structures were confirmed by mass spectrometry and NMR spectroscopic analysis. The radical quenching properties of 4-6 using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging assay showed activities similar to that of mixed tocopherols and carnosic acid.

Topics: Abietanes; Antioxidants; Biphenyl Compounds; Cyclization; Diterpenes; Free Radical Scavengers; Mass Spectrometry; Methylation; Molecular Structure; Nocardia; Nuclear Magnetic Resonance, Biomolecular; Oxidation-Reduction; Picrates; Plant Extracts; Rosmarinus; Structure-Activity Relationship

The photoprotective potential of the dietary antioxidants vitamin C, vitamin E, lycopene, beta-carotene, and the rosemary polyphenol, carnosic acid, was tested in human dermal fibroblasts exposed to ultraviolet-A (UVA) light. The carotenoids were prepared in special nanoparticle formulations together with vitamin C and/or vitamin E. Nanoparticle formulations, in contrast to dimethylsulphoxide, stablized lycopene in the cell culture medium and allowed efficient cellular uptake. The presence of vitamin E in the formulation further increased the stability and cellular uptake of lycopene. UVA irradiation of the human skin fibroblasts led to a 10-15-fold rise in metalloproteinase 1 (MMP-1) mRNA. This rise was suppressed in the presence of low microM concentrations of vitamin E, vitamin C, or carnosic acid but not with beta-carotene or lycopene. Indeed, in the presence of 0.5-1.0 microM beta-carotene or lycopene, the UVA-induced MMP-1 mRNA was further increased by 1.5-2-fold. This increase was totally suppressed when vitamin E was included in the nanoparticle formulation. Heme-oxygenase 1 (HO-1) mRNA expression was strongly induced by UVA irradiation but none of the antioxidants inhibited this effect at the concentrations used in this study. Indeed, beta-carotene or lycopene (0.5-1.0 microM) led to a further 1.5-fold rise in the UVA-induced HO-1 mRNA levels. In conclusion, vitamin C, vitamin E, and carnosic acid showed photoprotective potential. Lycopene and beta-carotene did not protect on their own but in the presence of vitamin E, their stability in culture was improved and the rise in MMP-1 mRNA expression was suppressed, suggesting a requirement for antioxidant protection of the carotenoids against formation of oxidative derivatives that can influence the cellular and molecular responses.

Topics: Abietanes; Adult; Antioxidants; Ascorbic Acid; beta Carotene; Biomarkers; Blotting, Northern; Carotenoids; Cells, Cultured; Chromatography, High Pressure Liquid; Cytoprotection; Diterpenes; DNA Damage; Fibroblasts; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Humans; Lycopene; Male; Matrix Metalloproteinase 1; Membrane Proteins; Plant Extracts; Radiation-Protective Agents; Skin; Ultraviolet Rays; Vitamin E