Protection of Lipids from Oxidation by Epicatechin, trans-Resveratrol, and Gallic and Caffeic Acids in Intestinal Model Systems

详细信息    查看全文

• 作者：Zohar Kerem ; David Chetrit ; Oded Shoseyov ; Gilly Regev-Shoshani
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2006
• 出版时间：December 27, 2006
• 年：2006
• 卷：54
• 期：26
• 页码：10288 - 10293
• 全文大小：120K
• 年卷期：v.54,no.26(December 27, 2006)
• ISSN：1520-5118

文摘

Consumption of polyphenols is associated with health promotion through diet, although many arepoorly absorbed in animals and humans alike. Lipid peroxides may reach the intestine and initiatedeleterious oxidation. Here we measured inhibition of the oxidation of linoleic acid (LA) in authenticfluid from rat small intestine (RIF) by two dietary polyphenols, a flavonoid, epicatechin (EC), and astilbene, resveratrol (RV), and by gallic (GA) and caffeic (CA) acids, and their partition coefficients.Both polyphenols inhibited 80%, and CA inhibited 65%, of the production of hexanal. GA was theweakest antioxidant in this assay. Interestingly, measuring peroxides production in RIF showed thatonly epicatechin inhibited the first stage of oxidation. The oxidizing agent, the antioxidant comound,the solution pH and lipophilicity are known to affect the total antioxidative activity. We suggest thatthe mechanism of this activity changes in accord with the environment: i.e., RV may act as a freeradial scavenger, but here, in protecting lipids in intestinal fluid from oxidation, it acts as a hydrogenatom donor. Since the concentration of phenolics is much higher in the intestinal fluid than is everachieved in plasma or other body tissues, it is suggested that their antioxidant activity could be exertedin the gastrointestinal tract (GIT), breaking the propagation of lipid peroxides oxidation and productionof toxic compounds.