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
Darjeeling tea 1839 from Kathmandu, Nepal. In 1841, he brought seeds of the Chinese tea plant ("Camellia sinensis") from Kumaun and began to experiment with tea planting in Darjeeling. The British government also established tea nurseries during that period (1847). Commercial development began during the 1850s. In 1856, the Alubari tea garden was opened by the Kurseong and Darjeeling Tea company, followed by others. According to the Tea Board of India, "Darjeeling Tea" can only refer to tea that has been cultivated, grown, produced, manufactured and processed in tea gardens (see 'Tea Estates' section below) in the hilly areas of Sadar Subdivision,