Bioavailability of tea polyphenols

In this book, the mannfacturing and chemistry of varions teas, including green tea, black tea, Pu-erh tea, white tea, and GABA tea, are discussed. We present the analysis, formation mechanism, and bioavailability of tea polyphenols. Various bioactivities of teas, including anticancer, anti-inflammatory, antiobesity, and antidiabetes, are also discussed. The flavor stability of ready-to-drink tea beverages is subsequently reviewed. 

Zou L-Q, Liu W, Liu W-L, Liang R-H, Li T, Liu C-M et al. Characterization and bioavailability of tea polyphenol nanoliposome prepared by combining an ethanol injection method with dynamic high-pressure microfluidization. J Agric Food Chem. 2014 62(4) 934-941. 

We herein report recent studies on the biological activities and bioavailability of tea polyphenols. 

Lambert JD, Yang CS. Cancer chemopreventive activity and bioavailability of tea and tea polyphenols. Mutat Res 2003 523-524 201-208. 

Lambert, J.D. et al., Piperine enhances the bioavailability of the tea polyphenol (-)-epigallo-catechin-3-gallate in mice, J. Nutr., 134, 1948, 2004. 

Another important field of application concerns food and beverages, especially wine, juices, and tea (A2, A11, A17, B4, K12, V7, Yl). The antioxidant components of food include vitamin E (a-tocopherol), vitamin A (retinoids), vitamin C (ascorbic acid), and also fi-carotene (provitamin A), other carotenoids (of which more than 600 compounds have been identified), flavonoids, simple phenols, and glucobrasicins (H3). Unfortunately, the TAC value of a food is not informative on the bioavailability of its antioxidants. It has been estimated that polyphenols are normally present in blood plasma at concentrations of 0.2-2 //M (PI). However, it has been demonstrated that feeding rats a quercetin-augmented diet can increase their plasma levels of quercetin and its metabolites up to 10-100 //M (M27), and transient increases in the concentration of plant-derived phenolic compounds can take place after ingestion of food and beverages, which may affect blood plasma TAC (see later). 

M.K. Parris, Bioavailability and activity of phytosome complexes from botanical polyphenols The silymarin, curcumin, green tea and grape seed extracts, Altem. Med. Rev., 14 3-8, 2009. 

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