Antioxidant Activity Of Polyphenol Extracts Research Articles

Obtaining and determining antioxidant activity of polyphenolic extracts obtained from propolis

Over the years, time has given us a whole series of novelties in the fi eld of natural medicine, which have managed to truly prove their value and keep up to date. Th e application of apitherapy has been known since ancient times and today the interest in this branch of natural medicine is growing worldwide. Among bee products, with an indisputable value is also propolis, which is currently widely studied, and as a result is the subject of multiple therapeutic uses based on evidence. Research in the fi eld of propolis preparations has expanded considerably and is of major medical and pharmaceutical interest. Propolis is an excellent anti-infl ammatory, healing and epithelializing, hepatoprotective, immuno-biostimulator, capillary tonic and tissue regenerator. It is remarkable that, due to its complexity and compositional variability, propolis retains its full antimicrobial capacity, unlike synthetic antibiotics, which bacteria develop resistance over time, requiring the periodic introduction of new antibiotics. Th e study on obtaining and analyzing propolis extracts, by determining the total polyphenolic and antioxidant activity, by scavenging method of the free radical DPPH, is an important premise for the use and development of new pharmaceutical forms containing propolis for multiple curative-prophylactic uses based on local raw materials.

The study of the antioxidant activity of polyphenol extracts from cranberry leaves on the model of insulin resistance

Topicality. In Ukraine, the number of patients with diabetes is growing rapidly, it ranks the 4th in the structure of diseases of the endocrine system, and it is one of the main causes of incapacitation and disability among the population and takes the second place by the number of deaths. Polyphenolic extracts from leaves of the heather (Ericaceae) family, in particular blueberries, cranberries and bearberry, in the previous studies demonstrated the presence of antioxidant, hypoglycemic and lipotropic properties. However, the pharmacological activity of extracts from cranberry leaves has not been sufficiently studied. Aim. To study the effect of polyphenolic extracts from cranberry leaves on the processes of LPO and the state of the antioxidant defense in the liver and serum in rats with the experimental insulin resistance. Materials and methods. The study was performed on white outbred male rats weighing 180 ± 15 g, kept in the vivarium of the NUPh. Insulin resistance was induced by keeping animals on a high fructose diet for 6 weeks according to the recommendations. The extracts were administered intragastrically in the dose of 200 μg/100 g of the body weight from the fourth week of the experiment for 14 days. The POL activity was assessed by the level of TBA reactants, diene conjugates and conjugated trienes in the liver and serum. The state of the antioxidant defense was assessed by the level of reduced glutathione, as well as the activity of catalase and superoxide dismutase. Indicators were determined by the spectrophotometric method. Results and discussion. The development of the experimental resistance was accompanied by an increase in LPS activity in the liver and serum of rats. In the serum of animals with IR the content of primary products of LPO increased in 1.75 times, the content of triene conjugates in 1.7 times, respectively, while the content of TBA reactants in 1.61 times. The introduction of the polyphenolic concentrate from cranberry leaves was accompanied by a sharp decrease in the products of lipid peroxidation both in the eserum and liver to almost ascending levels. There was normalization of the activity of enzymes of the first line of the antioxidant defense compared to animals with insulin resistance due to the presence of plant flavonoids in the extract. Conclusions. Thus, the data obtained indicate that the polyphenolic extract from cranberry leaves exhibits antioxidant properties in the liver and serum of rats with the experimental insulin resistance. The polyphenolic extract also restored the antioxidant defense of cells and the body as a whole. The data obtained indicate the need for further research to create a new herbal medicine for use in the treatment of insulin resistance and diabetes.

Antioxidant activity of polyphenolic extracts of filamentous fungus Mucor circinelloides (WJ11): Extraction, characterization and storage stability of food emulsions

Optimized extraction of antioxidants from Mucor circinelloides WJ11 (MCWJ11) biomass was studied. Storage, stability, composition and antioxidant properties in model food emulsion systems were also investigated. Both the extraction approach and solvent type were found to significantly (p<0.05) influence the recovery yield of antioxidants and their antioxidant capacity. The 90% aqueous binary solvent system with semi-polar solvents (i.e., acetone and ethanol) showed increased recovery levels of TPC, TFC and TCT, with the highest antioxidant bioactivity obtained using a pressurized liquid extraction. Ninety-day storage studies of microbial ethanolic extracts with accelerated storage/processing showed increased degradation of antioxidants at elevated temperatures (22–28 oC), with a negligible influence of white light. Substantial loss of microbial polyphenolic compounds was also observed, especially in fetal bovine serum at 37 °C with a 48 h stability test in biologically relevant buffers. Liquid–liquid fractionation of microbial ethanolic extracts led to the most active antioxidative fractions with ethyl acetate and 1-butanol. Comparatively, EtAc had better antioxidative activity (in a dose-dependent manner) against lipid oxidation in the tested food model emulsion systems. Furthermore, metabolic fingerprinting of the ethanolic extracts showed that the secondary metabolites of MCWJ11 were alkaloids, pigments, benzoic acids, terpenoids, cinnamic acids, benzopyrans, aspalathins and phloretins.

Разработка биотехнологии получения фитовеществ из вторичных продуктов переработки зерна

The present research features a new biotechnological approach for complex processing of secondary cereal products. The approach makes it possible to obtain new functional foods and ingredients, such as carbohydrate-protein concentrate, dietary fiber concentrates, biologically active substances, polyphenols, and xylo-oligosaccharides. The complex biotechnology involves oat bran biotransformation and includes chemical, hydrothermal, and enzymatic methods of extraction, which allows manufacturers to obtain functional ingredients with antioxidant and prebiotic properties. The concentrates obtained as a result of the study contained a significant amount of protein, hydrolysis products of polysaccharides (glucose, maltodextrins), and free polyphenols. The experiment produced concentrates of biologically active substances containing xylo-oligosaccharides and phenolic compounds. The content of polyphenols was 67% of the total amount in oat bran, protein – 6.9%, carbohydrates – 80.7% xylo-oligosaccharides whith prebiotic properties 35.3%–71.5%, and ash 11.3%. The obtained data indicated a high antioxidant activity of polyphenol extracts. The differences in antioxidant activity between various methods of extraction are associated primarily with the completeness of extraction and the stability of the extracted phenolic compounds. Ultrasonic treatment proved beneficial for the extraction kinetics and the polyphenol yield at the initial stage, with an increase in antioxidant properties. As for the antioxidant activity of polyphenol concentrate during storage, the research did not reveal changes for 8 months at a temperature of 20 ± 1°C and a relative humidity of 70 ± 5%. The study of the growth dynamics of Lactobacillus acidophilus and Bifi obacterium bifi um in media containing xylo-oligosaccharide concentrate confirmed the presence of prebiotic properties and their selectivity. The accumulation of biomass of prebiotic cultures occurred faster with the use of nutrient media with the use of xylo-oligosaccharide concentrate and lactulose, as compared with milk. Thus, the research confirmed the feasibility of biotechnology for transforming oat bran into functional ingredients, which makes it possible to use them in new technological solutions for products with bifidogenic properties.

The Antioxidant Activities of Polyphenolic Extracts from Grape Pomace on Seven Types of Chinese Edible Oils

The Antioxidant Activities of Polyphenolic Extracts from Grape Pomace on Seven Types of Chinese Edible Oils

Nutritional and functional characteristics of Erophaca baetica seeds, a legume endemic to the Mediterranean region

Erophaca baetica is a legume endemic to the Mediterranean region. Although the fruits and seeds are large, the presence of the “locoism” which produces the alkaloid, swainsonine has prevented its use as animal feed or for human nutrition. Their protein content and chromatographic profile, amino acid composition, fatty acid composition, and polyphenol contents have been determined in order to explore the potential of the E. baetica seeds as a source of dietary protein with functional components. The protein content was found to be 36% (w/w), and an amino acid analysis revealed a deficiency in sulphur amino acids, tryptophane, and lysine. The low lysine content is probably due to the abundance of alkaloids metabolically derived from this amino acid. Oleic and linoleic acids are the major fatty acids in the seeds. The antioxidant activity of polyphenol extracts was higher than the activity of the polyphenols extracted from most edible legume seeds. Hence, E. baetica seeds represent a promising source of functional and nutritional components on the condition that the anti-nutritional alkaloids are previously removed.

Antioxidant activity of polyphenolic extracts of Ichnocarpus frutescens

In the present study antioxidant activities by (1,1-diphenyl-2-picrylhydrazyl radical (DPPH), hydrogen peroxide, hydroxyl radical inhibition, hemolysis by hydrogen peroxide assay, reducing power and total antioxidant activities of polyphenolic extract of Ichnocarpus frutescens leaves were investigated. The flavonoids and total polyphenolic contents of the extract were also determined using standard methods. Phytochemical analyses revealed the presence of flavonoids, polyphenols, anthocyanins and simple phenolic acids. The results of antioxidant activities of polyphenol extract obtained by different in vitro methods were varied depending on the method used. Nevertheless, polyphenol extract showed significant inhibitory activities in all in vitro reactive oxygen species scavenging, might be attributed due to the high level of polyphenolic compound. Also, these various antioxidant activities were compared to α-tocopherol and l-ascorbic acid as reference antioxidant compounds. These findings provide evidence that the polyphenolic extract of I. frutescens is a natural source of antioxidant against oxidative damage.

Antioxidant Properties of Coriandrum Sativum (Coriander)

Antioxidants prevent the damage done to cells by free radical‐molecules that are released during the normal metabolic process of oxidation. Some of these free radicals include reactive oxygen free radicals species (ROS), reactive hydroxyl radicals (OH), the superoxide anion radical (O2), hydrogen peroxides (H2O2) and peroxy (ROO) which generates metabolic products that attack lipids in cell membranes or DNA. These are associated with several types of biological damage, DNA damage; carcinogenesis and cellular degeneration related to aging and also contribute to heart disease and arthritis. Spice coriander reduces fever and promotes a feeling of coolness. It is highly beneficial in the deficiency of vitamin A, B1, B2, C and iron. High concentration of polyphenol and other bio reactive components are reported in this spice. The present study was aimed to determine the antioxidant properties of coriander. The antioxidant activity of polyphenolic extracts of Coriandrum Sativum was evaluated in vitro with the systronic Spectrophotometer at 517nm based on the reduction of the stable DPPH free radical. Total phenolic content extracted from the coriander spice sample was 240.0 mg GAE/g dry weight of the spice as estimated by Folin's reagent and calculated with standard curve prepared with gallic acid by the same procedure. Antioxidant activity measured from coriander as DPPH free radical scavenging activity was dose dependent. Incubation of 10μl of extract in DPPH free radical solution eradicated free radicals and caused decrease in OD of 0.01. Antioxidants present in coriander extract were able to protect DNA damage against hydroxyl ion caused by (ferrous sulphate + H2O2 + ascorbate) Fenton's reaction. The study indicate coriander is one of the most effective spice in terms of antioxidant properties and can serve as natural source to develop the free radical scavengers and antioxidant agents.

Effect of Reddening–Ripening on the Antioxidant Activity of Polyphenol Extracts from Cv. ‘Annurca’ Apple Fruits

Apple is among the most consumed fruits worldwide, and several studies suggest that apple polyphenols could play a role in the prevention of degenerative diseases. 'Annurca' apple fruit undergoes, after harvest, a typical reddening treatment to turn the apples' skin red, and it is noted for its high firmness. This paper reports the effect of reddening-ripening treatment on polyphenol concentration and antioxidant activity of both peel and flesh extracts. The in vitro antioxidant properties have been compared with the protective effect against the cytotoxic effects of reactive oxygen species using Caco-2 cells as model system. Pretreatment of cells with different polyphenolic apple extracts provides a remarkable protection against oxidative damage. This effect seems to be associated with the antioxidant activity of 'Annurca' apple polyphenolic compounds. The flesh has antioxidant properties comparable to those possessed by the peel. Neither the reddening nor the fruit conservation causes changes in the antioxidant properties possessed by this apple variety. The data indicate that polyphenolic compounds in 'Annurca' apples are relatively stable in the peel and also in the flesh; therefore, the health benefits of polyphenols should be maintained during long-term storage. Finally, a diet rich in apple antioxidants could exert a beneficial effect in the prevention of intestinal pathologies related to the production of reactive oxygen species.

In vitro antioxidant activity of polyphenol extracts with antiviral properties from Geranium sanguineum L

Recent evidence shows that plant polyphenols exhibit antioxidant and radical scavenging properties. By three separate and complementary methods - DPPH assay, β-carotene-linoleic acid assay and NBT-reduction assay it was established that a polyphenol-rich extract from the medicinal plant Geranium sanguineum L. with strong anti-influenza virus activity, possessed antioxidant and radical scavenging capacities. For comparative reasons caffeic acid and the synthetic antioxidant BHT were used. Total soluble phenolic constituents of the MeOH extract measured by Folin-Ciocalteu reagent were found as 34.60% (w/w). Further it was demonstrated that the EtOAc fraction, retaining the majority of the in vivo protective effect exhibited a strong O 2 −scavenging activity while the n-BuOH fraction, containing the majority of the in vitro antiviral activity provoked generation of O 2 −. The O 2 − scavenging activity of all three preparations correlated with the rate of the protective effect shown in the murine model of experimental influenza virus infection. The present results are in accordance with our intensive studies on the mode of the protective effect of the plant extract which showed positively that the protection may possibly be attributed to the combination of more than one biological activities and that the use of antioxidants might be an useful approach in the treatment of influenza infection.