Phenolic content in tea green tea. Catechins constitute about 25% of the dry mass of a fresh tea leaf, although total catechin content varies widely depending on species, clonal variation, growing location, season, light variation, and altitude. They are present in nearly all teas made from "Camellia sinensis", including white tea, green tea, black tea and oolong tea. Of all the catechins in tea, EGCG is the main subject of scientific study with regard to its potential health effects. 4-Hydroxybenzoic acid, 3,4-dihydroxybenzoic acid (protocatechuic acid), 3-methoxy-4-hydroxy-hippuric acid and 3-methoxy-4-hydroxybenzoic acid (vanillic acid) are the main catechins metabolites found in humans after consumption of green
Camellia sinensis Robert Sweet shifted all formerly "Thea" species to the genus "Camellia" in 1818. The name "sinensis" means "from China" in Latin. Four varieties of "Camellia sinensis" are recognized. Of these, "C. sinensis" var. "sinensis" and "C. sinensis" var. "assamica" (JW Masters) Kitamura are most commonly used for tea, and "C. sinensis" var. "pubilimba" Hung T. Chang and "C. sinensis" var. "dehungensis" (Hung T. Chang & BH Chen) TL Ming are sometimes used locally. There are hundreds, if not thousands of cultivars of "C. sinensis." Some Japanese cultivars include: "Camellia sinensis" is native to East Asia, the Indian Subcontinent and Southeast