A subclass of flavonoids found in tea. Up to 30% of the dry weight of green tea leaves is catechins. Scientists believe catechins to be one of the important active substances that gives green tea extract its cancer-preventive and possibly curative properties in animal studies. But population studies show no such clear-cut protective effect.
These are polyphenolic compounds which occur in plants naturally. One of these, polyphenol oxidase, causes the darkening of certain vegetables when these vegetables are cut by a knife thus rupturing the cell wall and exposing the chemical to oxygen. It is also responsible for turning freshly picked tea leaves black (as in black tea--this process is explained elsewhere in "The Tea Man’s Tea Talk"). PIGALLOCATECHIN GALLATE (EGCG, ECG, EGC, EC): A group (family) which are directly related to catechins (see above). These appear mostly in green tea but also in black tea in a somewhat changed configuration.
A class of flavonoids found in green tea with powerful cell DNA protection properties. The primary catechin found in green tea is epigallocatechin gallate (EGCG).
class of polyphenol present in high concentrations in green tea, but found in varying levels in other teas derived from the teaplant
A group of related polyphenolic compounds which occur in plants and are darkened by the action of certain plant enzymes and oxygen an example of browning of cut fruit and vegetables. Catechins can function as antioxidants.
One of a group of antioxidants known as flavonoids that occur naturally in tea. Catechins are said to be 20 times more effective as antioxidants than vitamin C.