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
Angelica sinensis Angelica sinensis Angelica sinensis, commonly known as dong quai or "female ginseng" is a herb from the family Apiaceae, indigenous to China. "Angelica sinensis" grows in cool high altitude mountains in China, Japan, and Korea. The yellowish brown root of the plant is harvested in fall and is a well-known Chinese medicine used over thousands of years. The dried root of "A. sinensis" is commonly known as Chinese angelica () and is widely used in Chinese traditional medicine in the belief it benefits women's health, cardiovascular conditions, osteoarthrosis, inflammation, headache, infections, mild anemia, fatigue and high blood pressure. The dong