http://www.mdpi.com/journal/nutrients/special_issues/polyphenolic/ Dear Colleagues, Polyphenols are a complex group of phytochemicals that have ubiquitous distribution in plants, some fungi and even some micro-organisms. Most are best known for their potent antioxidant potential, however this is only one of a plethora of activities that have been associated with polyphenols. Some have hormone-like activity, behaving as estrogens or estrogen antagonists (e.g. phytoestrogens), others are protein kinase inhibitors, anti-inflammatory agents, antimicrobials, anti-fungals, and even insect repellants or attractants. Others control cell cycle progression, cellular differentiation, senescence and apoptosis. They may modulate enzymes associated with eicosanoid metabolism and thereby affect cell signaling, lipid peroxidation, and DNA-damage. Some polyphenols are excellent chelating agents and can interfere with metal induced oxidative damage. As well as being antioxidants themselves, several polyphenols, particularly the flavonoids, have been shown to modulate the expression of endogenous antioxidant molecules and proteins such as glutathione, glutathione peroxidase, superoxide dismutase and catalase. Because of their wide-ranging activities, polyphenols are aggressively being studies for their activities as human and animal health promotion agents and effective disease preventive or treatment agents for a number of human ailments including: Alzheimer’s disease, cancer, atherosclerosis and other cardiovascular diseases, multiple sclerosis, and autoimmune disorders. Major issues continue to be identifying the “active metabolites” and their mechanisms of action as well as determining the barriers to bioavailability of polyphenols from foods, herbs and extracts, and determining the “recommended” levels that should be being consumed by humans for optimal health. Prof. Dr. Kelly Meckling Guest Editor {snippet name="submission_info"} http://www.mdpi.com/2072-6643/2/12/1231/ Polyphenols are the biggest group of phytochemicals, and many of them have been found in plant-based foods. Polyphenol-rich diets have been linked to many health benefits. This paper is intended to review the chemistry and biochemistry of polyphenols as related to classification, extraction, separation and analytical methods, their occurrence and biosynthesis in plants, and the biological activities and implications in human health. The discussions are focused on important and most recent advances in the above aspects, and challenges are identified for future research. http://www.mdpi.com/2072-6643/2/12/1231/ Fri, 10 Dec 2010 00:00:00 CET Nutrients 2010-12-10 2 12 Review 1231 1246 2072-6643 Chemistry and Biochemistry of Dietary Polyphenols 2010-12-10 doi: 10.3390/nu2121231 Rong Tsao http://www.mdpi.com/2072-6643/2/10/1048/ It has been suggested that the dietary intake of antioxidant supplements could be a useful strategy to reduce the incidence of diseases associated with oxidative stress. The aim of present work is to study the possibility to obtain compounds with antioxidant activity from wine wastes using water as solvent. Results have shown that it is possible to obtain flavan-3-ol compounds from wine wastes both from V. vinifera (cv. Cabernet Sauvignon and Merlot) and V. labrusca (cv. Bordo and Isabella) species. The main phenolic compounds found in the extracts were catechin and epicatechin, followed by procyanidin B3, procyanidin B1, procyanidin B2, gallic acid, epigallocatechin, and procyanidin B4. All flavan-3-ol extracts showed significant in vitro and in vivo activities. It was found that the extracts were able to prevent lipid and protein oxidative damage in the cerebral cortex, cerebellum and hippocampus tissues of rats. Although further studies are necessary, these flavan-3-ol extracts show potential to be used to reduce the incidence of degenerative diseases associated with oxidative stress. http://www.mdpi.com/2072-6643/2/10/1048/ Mon, 11 Oct 2010 00:00:00 CEST Nutrients 2010-10-11 2 10 Article 1048 1059 2072-6643 Flavan-3-ol Compounds from Wine Wastes with in Vitro and in Vivo Antioxidant Activity 2010-10-11 doi: 10.3390/nu2101048 Gustavo Scola Danusa Conte Patrícia Wilmsen Dalla-Santa Spada Caroline Dani Regina Vanderlinde Claudia Funchal Mirian Salvador