Green Tea Polyphenols
Green tea polyphenols are members of the flavonoids. Flavonoids are what give color to many flowers and fruits. As a whole, flavonoids are able to act against allergens, carcinogens, and viruses. This accessory nutrient is a powerful antioxidant, even stronger than vitamin C and vitamin E. Green tea polyphenols are effective for disrupting the formation of nitrosamines. Nitrosamines are the compounds formed when nitrites bind to amino acids. Nitrites are found in the curing of ham, bacon, and the like. Sources of flavonoids in general include: green tea, citrus fruits, legumes, and berries.
The polyphenols are the active players in green tea, mediating both taste profile and biological actions. From a chemical perspective, green tea polyphenols are catechins, phytochemicals composed of several linked ring-like structures. Attached to each structure are chemical tags called phenol groups, and because there are many phenol groups, these catechins are called polyphenols. Polyphenols act as antioxidants. They protect cells and body chemicals against damage caused by free radicals, reactive atoms that contribute to tissue damage in the body. For example, when low-density lipoprotein (LDL) cholesterol is oxidized, it can become glued to arteries and cause coronary heart disease. Polyphenols can also block the action of enzymes that cancers need for growth and they can deactivate substances that promote the growth of cancers. The polyphenol most strongly associated with cancer prevention is epigallocatechin-3-gallate, or EGCG.
All tea contains polyphenols. Teas and polyphenols isolated from tea have been shown in the laboratory to act as scavengers of oxygen and nitrogen-free radicals, protecting the fatty membranes of cells, proteins and DNA. However, the results of human studies of tea and polyphenols to date (2001) have been inconsistent and have yet to prove anything one way or the other as regards the value of polyphenols. In native green tea, approximately 15-30% of the weight of the leaf is composed of polyphenols; over 50% of this polyphenol fraction is comprised of (-) Epigallocatechin Gallate(EGCG), the most biologically active and influential polyphenol in green tea. Other components include the unique amino acid theanine, carotenoids, chiorophyll and caffeine. Anthocyanidins, plant pigments also found in Bilberry, Ginkgo biloba and pine bark extracts (Pycnogenol), are also found in green tea. Caffeine occurs in green tea leaves at a level of 3%; brewed green tea contains approximately 35-50 mg of caffeine per cup, contrasted to a cup of coffee, which contains between 75-95mg.
Green tea is a popular beverage consumed worldwide. The epicatechin derivatives, which are commonly called `polyphenols', are the active ingredients in green tea and possess antioxidant, anti-inflammatory and anti-carcinogenic properties. Studies on human skin have demonstrated that green tea polyphenols (GTP) prevent ultraviolet (UV)-B-induced cyclobutane pyrimidine dimers (CPD), which are considered to be mediators of UVB-induced immune suppression and skin cancer induction. GTP treated human skin prevented penetration of UV radiation, which was demonstrated by the absence of immunostaining for CPD in the reticular dermis. The topical application of GTP or its most potent chemopreventive constituent (-)-epigallocatechin-3-gallate (EGCG) prior to exposure to UVB protects against UVB-induced local as well as systemic immune suppression in laboratory animals. Additionally, studies have shown that EGCG treatment of mouse skin inhibits UVB-induced infiltration of CD11b+ cells. CD11b is a cell surface marker for activated macrophages and neutrophils, which are associated with induction of UVB-induced suppression of contact hypersensitivity responses. EGCG treatment also results in reduction of the UVB-induced immunoregulatory cytokine interleukin (IL)-10 in skin as well as in draining lymph nodes, and an elevated amount of IL-12 in draining lymph nodes. These in vivo observations suggest that GTPs are photoprotective, and can be used as pharmacological agents for the prevention of solar UVB light-induced skin disorders associated with immune suppression and DNA damage.
Green tea polyphenols can made of all kinds of drinks, such as tea carbonated drinks, tea cola, tea icecream. Tea ice sucker, ice tea, degrease caffeine tea, canister tea drinks as teabutter, clean tea wine, tea arrack. The common accretion amount is about 0.02-0.4%.
Green tea polyphenols can apply the course of processing0 and freshkeeping to fruit juice, adding to GTP by 0.02% can restraining the orange juice is annual concentrated foul, and also GTP by 0.005-0.01% in vitamin A, B, and B carrot, to guarantee the effective finished product and product quality.