Anti-aging cosmetics are often sought after in order to slow down the aging process. Free radicals one of main causes skin aging, and therefore antioxidants used anti-aging cosmetics. The aim this study was investigate which method is most suitable for determining antioxidant capacity these products. Having samples extracted, extracts obtained determined by following spectrophotometric methods:...

BACKGROUND The interest in potato juice as a therapeutic agent goes back to the 19th century but its application was not supported by any knowledge about biological activity of this raw material. Factors restricting the medical application of potato juice include its inattractive sensory and functional properties. The aim of the presented investigations was preliminary evaluation of the biologi...

We describe a reversed-phase HPLC method that uses gradient elution and diode array detection to determine four biologically active phenolic constituents of red wines: gallic acid, trans-resveratrol, quercetin and rutin. The method permits direct injection without sample pre-treatment. ODS Hypersil served as the stationary phase; the gradient was formed by acetic acid, methanol, and water. Each...

Antioxidant capacities of 56 selected Chinese medicinal plants were evaluated using the Trolox equivalent antioxidant capacity (TEAC) and ferric reducing antioxidant power (FRAP) assays, and their total phenolic content was measured by the Folin-Ciocalteu method. The strong correlation between TEAC value and FRAP value suggested that the antioxidants in these plants possess free radical scaveng...

The antioxidant capacities and the total phenolic content in cocoa liquor directly manufactured chocolate from an artisan manufacturer were measured using different in vitro methods (BR, TEAC, and Folin– Ciocalteu Reagent). These parameters were then compared with those of a chocolate made by a leading manufacturing company producing chocolate and cocoa-containing products. A statistical analys...

The purpose of this study was to analyze polyphenol rich beverages (vitamin enhanced waters (VEWs), fruit juices and berry juices) to determine free polyphenol concentrations and free polyphenols per Calorie based on a serving size. The Folin-Ciocalteu reagent was used in a colorimetric assay based on a catechin standard. Fruit and berry juices contained, on average, more than eight-times the c...

A novel polymeric material with antioxidant properties and suitable for ophthalmic application was synthesized by free radical grafting reaction between 2-hydroxyethyl methacrylate and quercetin. The presence of quercetin in the polymeric chain was confirmed by FT-IR and UV-Vis analyses, while an estimation of the amount of quercetin bound per gram of polymer was obtained by the Folin-Ciocalteu...

In the current study, changes in health-promoting substances (phenolics and flavonoids) and antioxidant activity of carrot and mango beverages during storage at 25 and 35°C for 30, 60 and 90 days were investigated. The total phenolic content was determined using Folin–Ciocalteu method. The antioxidant activity was based on the evaluation of free–radical scavenging activity (FRSA) using DPPH rad...