ABSTRACT
Tea (Camellia sinensis) originated in the southern part of Yunna province in southwest China and has since spread worldwide. ere are two major varieties of tea in the eaceae family: Camellia sinensis var. sinensis, which is characterized by its small leaves and bushlike plants, originating in China and growing in some countries in Southeast Asia with a mild cold climate, and
3.1 Introduction 39 3.2 Metabolism 44
3.2.1 Methylation 44 3.2.2 Glucuronidation and Sulfation 45 3.2.3 Ring Fission 47 3.2.4 Metabolism in Animals 49 3.2.5 Metabolism in Humans 50
3.3 Bioavailability 51 3.3.1 GTP Bioavailability in Animals 51 3.3.2 GTP Bioavailability in Humans 52
3.4 Safety Study of Green Tea Polyphenols 53 3.5 Conclusion and Perspectives 53 References 54
Camellia sinensis var. assamica, which is a large-leaved tree discovered in the region of southwest China and India and immigrated to several other countries with a semitropical climate. Owing to its unique flavor and taste, the sinensis tea dominates green tea production, whereas the assamica tea is mainly used for black tea production because of its high contents of catechins and tannins . Original tea consumption was mainly for its central nerve-stimulating and soothing effects, and tea drinking has been linked to health for centuries.
