Heat-Epimerized Tea Catechins Rich in Gallocatechin Gallate and Catechin Gallate Are More Effective To Inhibit Cholesterol Absorption than Tea Catechins Rich in Epigallocatechin Gallate and Epicatechin Gallate

Abstract

It has been known that tea catechins, (-)-epicatechin (1), (-)-epigallocatechin (2), (-)-epicatechin gallate (3), and (-)-epigallocatechin gallate (4) are epimerized to(-)-catechin (5), (-)-gallocatechin (6), (-)-catechin gallate (7), and (-)-gallocatechin gallate (8), respectively, during retort pasteurization. We previously reported that tea catechins, mainly composed of 3 and 4, effectively inhibit cholesterol absorption in rats. In this study, the effect of heat-epimerized catechins on cholesterol absorption was compared with tea catechins. Both tea catechins and heat-epimerized catechins lowered lymphatic recovery of cholesterol in rats cannulated in the thoracic duct and epimerized catechins were more effective than tea catechins. The effect of purified catechins on micellar solubility of cholesterol was examined in an in vitro study. The addition of gallate esters of catechins reduced micellar solubility of cholesterol by precipitating cholesterol from bile salt micelles. Compounds 7 and 8 were more effective to precipitate cholesterol than 3 and 4, respectively. These observations strongly suggest that heat-epimerized catechins may be more hypocholesterolemic than tea catechins.

Chá verde brasileiro (Camellia sinensis var assamica): efeitos do tempo de infusão, acondicionamento da erva e forma de preparo sobre a eficiência de extração dos bioativos e sobre a estabilidade da bebida

“…Os maiores produtores de Camellia sinensis são a China e a Índia e os chás provenientes desses países já foram objeto de muitos estudos (ASTILL et al, 2001;FERNANDEZ et al, 2002;LIN et al, 2003;PERVA-UZUNALIC et al, 2006). O cultivo do chá verde é hoje, entretanto, realizado em diversos países em praticamente todos os continentes (CHAN;LIM;CHEW, 2007;YAO et al, 2005).…”

“…Originário da China, o chá é cultivado e consumido pelas suas características de aroma e sabor e propriedades medicinais em mais de 160 países, especialmente asiáticos (KUMUDAVALLY et al, 2008;MIYATA, 2000). Os chás de Camellia sinensis podem ser classificados em três tipos básicos: preto, verde e oolong, diferenciando-se pelo beneficiamento das folhas.…”

“…Diversos estudos têm mostrado os benefícios do consumo de chá verde, incluindo redução dos níveis de colesterol, atividades imunoestimulatória, antimicrobiana e antioxidante, auxiliando na prevenção de doenças crônico-degenerativas, como o câncer e doenças cardiovasculares (CHENG, 2006;IKEDA et al, 2003;…”

Inhibitory Effects of Eight Green Tea Catechins on Cytochrome P450 1A2, 2C9, 2D6, and 3A4 Activities

“…Therefore, unwanted drug interactions may occur when green tea beverage and medicinal drug are taken at the same time. Green tea catechins, the major components of which are (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin-3-O-gallate (ECG), and EGCG, are found in various tea products, such as green tea, oolong tea, and black tea (20). The consumption of canned and bottled green tea beverages is increasing in Asian countries, particularly in Japan.…”

Epigallocatechin 3-gallate Binds to Human Salivary α-Amylase with Complex Hydrogen Bonding Interactions

“…17 Since it is an epimer of EGCG, its conformation could not be specified at the active site of HSA. The rest of five theaflavin family flavonoids were too large to dock into the active site of HSA.…”