Natural antioxidant ingredients contained in some plants are much less toxic than those in synthetic antioxidants. Under the circumstances of nature respect, synthetic antioxidants are boycotted by customers increasingly because of it’s safety issues; meanwhile, many countries in the world are developing all kinds of natural antioxidants in order to replace synthetic antioxidants. The polyphenols found in tea as natural antioxidants are incomparable to those of other plants.
Tea is the most widely consumed plant-based beverage in the world. Three basic polyphenol groups can be distinguished in tea leaves: catechin, theaflavins and thearubigenes. Both green and black tea contains a similar quantity of flavonoids, differing in respect of their chemical structures. Green tea is characterized by a higher content of simple flavonoids-catechins which become transformed to more complex compounds during the fermentation of tea leaves. Other products of polyphenol oxidation are tannins.
The anticarcinogenic potential of tea polyphenols may be attributed to their ability to bind directly to carcinogens, induce Phase II enzymes such as UDP-glucuronosyltransferase (UDP-GT), and inhibit heterocyclic amine formation. Long-term ingestion of green tea increases UDP-GT activity, and the increased glucuronidation through UDP-GT induction is postulated to contribute to the anticarcinogenic effect of green tea. This facilitates the metabolism of chemical carcinogens into inactive products that are readily excreted.
Unique characteristics of green tea polyphenols include their ability to induce growth arrest and apoptosis in tumor cells, especially in epithelial-type cells, as well as protecting normal epithelial cells from carcinogens.The life span of both normal and cancer cells is significantly affected by the rate of apoptosis, a programmed type of cell death that differs from necrotic cell death and is regarded as a normal process of cell elimination. Intake of tea either as a liquid or as a tea extract may inhibit the development of cancers of the skin, lung, esophagus, stomach, liver, duodenum and small intestine, pancreas, colon, bladder, prostate, ovary, oral cavity, and mammary gland.
Tea polyphenols act as antioxidants and prevent tissues from damage by free radicals. They appear to protect genes from the mutagenic effects of environmental factors. Tea may be used as a therapeutic agent against premalignant lesions in the mouth. The polyphenols eliminate active forms of carcinogens and other toxicants, accounting for lower risk of cancer. Follow OKCHEM.com in linkedin here!