Combination Of Natural Antioxidants Research Articles

More natural more better: triple natural anti-oxidant puerarin/ferulic acid/polydopamine incorporated hydrogel for wound healing

BackgroundDuring wound healing, the overproduction of reactive oxygen species (ROS) can break the cellular oxidant/antioxidant balance, which prolongs healing. The wound dressings targeting the mitigation of ROS will be of great advantages for the wound healing. puerarin (PUE) and ferulic acid (FA) are natural compounds derived from herbs that exhibit multiple pharmacological activities, such as antioxidant and anti-inflammatory effects. Polydopamine (PDA) is made from natural dopamine and shows excellent antioxidant function. Therefore, the combination of natural antioxidants into hydrogel dressing is a promising therapy for wound healing.ResultsHydrogel wound dressings have been developed by incorporating PUE or FA via PDA nanoparticles (NPs) into polyethylene glycol diacrylate (PEG-DA) hydrogel.This hydrogel can load natural antioxidant drugs and retain the drug in the gel network for a long period due to the presence of PDA NPs. Under oxidative stress, this hydrogel can improve the activity of superoxide dismutase and glutathione peroxidase and reduce the levels of ROS and malondialdehyde, thus preventing oxidative damage to cells, and then promoting wound healing, tissue regeneration, and collagen accumulation.ConclusionOverall, this triple antioxidant hydrogel accelerates wound healing by alleviating oxidative injury. Our study thus provides a new way about co-delivery of multiple antioxidant natural molecules from herbs via antioxidant nanoparticles for wound healing and skin regeneration.Graphic

Evaluation of small scale n‐heptane fire extinguishing efficacy by natural antioxidants based pyrotechnic compositions: An experimental study

SummaryThe conventional pyrotechnic compositions (PCs) for firefighting application mostly consist of potassium nitrate, chlorate or perchlorate as oxidants and organic resin‐like phenol‐formaldehyde, melamine‐formaldehyde, epoxy resin and polyurethanes are used as reducers. Unfortunately, there are also some potential disadvantages to the use of conventional compositions. These are related to high combustion temperature with the generation of heat and flame which may cause secondary fire chances and hazards associated with the use of organic resins. Exposure to phenol, melamine, epoxy resins and polyurethanes are considered as a life‐threatening occupational hazard. Under the present study, new pyrotechnic compositions were prepared with the combination of natural antioxidants like ascorbic acid and gallic acid as reductant and mixture of potassium nitrate with potassium chlorate as oxidant. Fire extinguishing efficacies, calorific value, burn rate, the flame temperature of newly developed compositions was evaluated against potassium nitrate and phenol‐formaldehyde resin‐based conventional composition. Although both the new and conventional composition has shown good fire extinguishing efficacies, extinguishing 4.57 KW of small scale n‐heptane pool fire in 3 to 4 seconds, these newly developed compositions showed 67% to 76% reduction in flame temperature. It was also found that these new compositions exhibit a faster burn rate and lower calorific value than the conventional composition. To understand the fire extinguishing mechanism by the discharged aerosol particulate, its physical and chemical characteristics were assessed by a series of techniques viz; HRXRD, SEM, FTIR, EDX.

Combined effect of natural antioxidants and antimicrobial compounds during refrigerated storage of nitrite-free frankfurter-type sausage

The effects of nisin (200 and 400 ppm), ε-polylysine (0.1 and 0.2%) and chitosan (0.5 and 1%) in combination with a Mixed Extract (green tea, stinging nettle and olive leaves extracts) on the physicochemical, microbiological characteristics, fatty acid composition and sensory attributes of the nitrite-free frankfurter-type sausages were assessed during 45 days of storage. The results revealed no significant differences on moisture, fat, protein, ash, salt and water activity (aw) among treatments. 1% Chitosan + Mixed Extract sausages displayed the lowest thiobarbituric acid reactive substances (TBARS) and total volatile nitrogen (TVN) values compared to Control after 45 days of refrigerated storage. Combinations of 0.2% ε-Polylysine or 1% Chitosan with Mixed Extract were effective to inhibit total viable count (TVC), yeasts and molds growth. 1% Chitosan preserved the luminosity of sausages during refrigerated storage. However, redness values of 1% Chitosan treatment was lower than those obtained from Control sausages and a significant increase was observed between days 30–45. Total amounts of saturated, monounsaturated and polyunsaturated fatty acids (SFA, MUFA, and PUFA) of frankfurter-type sausages were not largely influenced by the combination of natural antioxidants and antimicrobial compounds. Combinations of 0.2% ε-Polylysine and 1% Chitosan with Mixed Extract were effective to improve the shelf life of nitrite-free frankfurter-type sausages. Therefore, these combinations could be considered as promising nitrite replacer in frankfurter-type sausages.

Synergistic Anti-Oxidative Effects of Lycopene with Other Bioactive Compounds

Lycopene belongs to the carotenoid family, which has more than 700 members. In human serum, only 14 caroteinoids have been identified, and, among these, lycopene was the most abundant. Lycopene is regarded as one of the most efficient singlet oxygen quencher and peroxyl radical scavenger of all the carotenoids and may represent an important defense mechanism in the human body. Singlet oxygen and free radicals can cause biological damage to important macromolecules and membrane constituents, and the presence of natural antioxidants may help to control these degradative reactions.The oxidation of low density lipoproteins (LDL) has been implicated in the development of atherosclerosis which makes the antioxidants that protect LDL potential antiatherogenic agents. There is growing evidence that certain combinations of natural antioxidants have synergistic antioxidant activity, that is, the actual inhibitory activity of the mixture is greater than the additive activities of the individual antioxidants. Lycopene on its own can retard the oxidation of LDL, but in combination with vitamin E, a synergistic effect is observed. There is clear evidence that lycopene in association with α-tocopherol synergistically inhibits the proliferation of two prostate carcinoma cell lines. Polyphenols are very potent antioxidants found in tomatoes and many other fruits, vegetables, and herbs. The polyphenols glabridin, rosmarinic acid, and carnosic acid, when used in combination with lycopene, inhibited the oxidation of LDL to a greater extent than the additive values by 32%, 32%, and 15%, respectively. Extracts and powders containing mixtures of antioxidants also showed synergism. Tomato oleoresin produced a 5-fold increase in antioxidant activity against LDL oxidation when compared to pure lycopene at the same concentration. A 33% increase in LDL inhibition was observed when lycopene was used with garlic powder. Of the six major carotenoids found in human blood and tissue, lycopene plus lutein produced the greatest synergistic effect against oxidation of multilamellar liposomes. It also has been shown that low concentrations of 1,25-dihydroxylvitamin D3 and lycopene synergistically inhibit cell proliferation and differentiation in HL-60 leukemic cells. A number of hypotheses have been put forward to explain the synergistic effects between lycopene and other natural antioxidants. It has been suggested that the synergistic effects may be related to their physicochemical properties and or their location within the biomembrane or LDL particle; that one antioxidant is able to regenerate the second antioxidant; or that vitamin E and lycopene affect different signal transduction pathways leading to the synergistic inhibition of cell proliferation.

Reduced Concentrations of Soluble Adhesion Molecules after Antioxidant Supplementation in Postmenopausal Women with High Cardiovascular Risk Profiles – A Randomized Double-Blind Study

Background: One of the suggested mechanisms of increased cardiovascular risk in postmenopause is a loss of the antioxidant effects of estrogens. It has been shown that classical cardiovascular risk factors increase oxidative stress on the arterial wall, and that endothelial cells react to this insult by increased expression of cellular adhesion molecules (CAM), which in turn are markers of arterial wall inflammation. Methods: A randomized, placebo-controlled, double-blind study was performed in 60 postmenopausal women with high cardiovascular risk profiles, but free from clinical atherosclerotic disease. Patients were randomized to either antioxidant supplementation (using a combination of natural antioxidants; n = 30) or placebo (n = 30), and followed for 12 weeks. The concentrations of the adhesion molecules sVCAM-1 and sICAM-1 were measured by ELISA at baseline and at the end of the study, as well as total cholesterol, LDL, HDL, triglycerides and blood pressure. Results: 27 women in the antioxidant supplementation group and 29 on placebo completed the study. At baseline, there were no significant differences in measured parameters between the groups: sICAM-1 concentrations were 341.8 ± 116.9 vs. 349.9 ± 104.6 ng/ml (active treatment vs. placebo; p = n.s.) and sVCAM-1 concentrations were 780.5 ± 325.8 vs. 761.0 ± 333.7 ng/ml (p = n.s.). In contrast, at the end of the study, sICAM-1 concentrations were 301.6 ± 56.0 vs. 356.0 ± 134.8 ng/ml (active treatment vs. placebo; p = 0.053) and sVCAM-1 concentrations were 656.0 ± 326.5 vs. 818.5 ± 381.0 ng/ml (p = 0.04). There were no significant differences between or changes within the groups in measured cholesterol and blood pressure. Conclusion: Antioxidant supplementation reduces serum concentrations of endothelium-derived adhesion molecules sICAM-1and sVCAM-1 in postmenopausal women with high cardiovascular risk profiles.