Flavonoids in green tea

Green tea contains polyphenols, which include flavanols, flavandiols, flavonoids, and phenolic acids; these compounds may account for up to 30% of the dry weight.

All teas from Camellia Sinensis leaves contain natural flavonoids. The levels of flavonoids vary among the type of tea – black, green, oolong and white. On average, the flavonoid content of black tea is approximately 180 mg per cup and in green tea, approximately 160 mg per cup.

Flavonoids are composed of a variety of health-promoting compounds and might have antioxidative, antimicrobial, and possibly anticarcinogenic, and cardioprotective effects.

Flavonoids are capable of modulating the activity of enzymes and affect the behavior of many cell systems and exerting beneficial effects on the body.

The major flavonoids of green tea are various catechins, which are found in greater amounts in green tea than in black or Oolong tea. There are four kinds of catechins mainly find in green tea: epicatechin, epigallocatechin, epicatechin-3-gallate, and EGCG.

Many of the beneficial effects of green tea are related to its catechin, particularly (-)-epigallocatechin-3-gallate, content. Long-term consumption of tea catechins could be beneficial against high-fat diet-induced obesity and type II diabetes and could reduce the risk of coronary disease.

Tea polyphenols, catechins and flavonols scavenge reactive oxygen species, and chelate transition metal ions in a structure‐dependent manner. These flavonoids are antioxidants by virtue of the number and arrangement of their phenolic hydroxyl groups.
Flavonoids in green tea