Cocoa and cocoa products have received much attention due to their significant polyphenol contents. Cocoa and cocoa products, namely cocoa liquor, cocoa powder and chocolates (milk and dark chocolates) may present varied polyphenol contents and possess different levels of antioxidant potentials. For the past ten years, at least 28 human studies have been conducted utilizing one of these cocoa p...

Objective: Polyphenol oxidase or PPO (EC 1.14.18.1) is considered the enzyme responsible for quality deterioration and browning in different fruits during postharvest period. The objective of this study was to evaluate the antibrowning (inhibition of polyphenol oxidase activity) effect of Cysteine, Ascorbic acid, citric acid, kojic acid and glycine at two different pH (6 and 7) in  hawthorn. Me...

Dietary polyphenols in tea and wine have been associated with beneficial health effects. After ingestion, most polyphenols are metabolized by the colonic microbiota. The current study aimed at exploring the interindividual variation of gut microbial polyphenol bioconversion from 10 healthy human subjects. In vitro fecal batch fermentations simulating conditions in the distal colon were performe...

We report here a novel bioelectrode based on self-assembled multilayers of polyphenol oxidase intercalated with cationic polyallylamine built up on a thiol-modified gold surface. We use an immobilization strategy previously described by Hodak J. et al. (Langmuir 1997, 13, 2708-2716) Quartz crystal microbalance with electroacustic impedance experiments were carried out to follow quantitatively t...

Phloroglucinol and resorcinol are not substrates for clingstone peach (Prunus persica) polyphenol oxidase, but they react with 4-methyl-o-quinone, produced either enzymatically or nonenzymatically, to give an intense red or red-brown color with a maximal absorption at about 470 nanometers. Several colored products were isolated from an ethyl acetate extract of the reaction by two-dimensional th...

Objective: Determination and comparison of the effect of infusion time on the antioxidant activity and total polyphenol contents of bagged and loosely packed black teas. Materials and Methods: For twenty loosely packed and eleven bagged tea samples, the antioxidant activity and total polyphenol content were analyzed using FRAP and Folin-Ciocalteau methods, respectively. The ANOVA with Tukey pos...

Partridgeberry (Vaccinium vitis-idaea) is a polyphenol-rich berry of the Ericaceous family, grown in Newfoundland and Labrador province of Canada. The aims of this study were to identify extraction solvents for the maximum recovery of polyphenols, to establish fractionation technique for isolation of major sub-classes of polyphenols, and to evaluate antioxidant and cytoprotective properties of ...

Herb teas, Arabian jasmine, Balsam pear, Barley grass, Guava, Hardy rubber tree, Japanese persimmon, Jobs tears, Oolong tea, Puerh tea and Wolofberry have been consumed as beverages for health in Asia. Oxidative stress induces various diseases. Some of them, Arabian jasmine, Guava, Hardy rubber tree, Japanese persimmon, Oolong tea and Puerh tea, have high total polyphenol content and antioxidan...

In the article title of the original publication, the word ''polyphenol'' was incorrectly published as ''ployphenol''. The correct article title should read as follows. ''High quality RNA isolation from polyphenol-, poly-saccharide-and protein-rich tissues of lentil (Lens culinaris)'' Open Access This article is distributed under the terms of the Creative Commons Attribution License which permi...