پلی فنول چای سبز: مواد آرایشی چند منظوره Green Tea Polyphenols: Versatile Cosmetic Ingredient

Increasing spending power has made the cosmetic industry one of the rapidly growing sectors in India. Indian cosmetic sector analysis (2009-2012) done by market researchers RNCOS shows that the last year sale of cosmetics in India was around INR 356.6bn. Herbs have been used in medicines and cosmetics from centuries. Their potential to treat different skin diseases, to adorn and improve the skin appearance is well-known. The tea plant, Camellia sinensis, is a member of the Theaceae family. Tea is a large shrub with white flowers and is indigenous to Asia and China, but commercially grown in Africa, Sri Lanka, Malaysia and Indonesia. The young leaves and buds are used for production of black, oolong, and green tea. Unlike black and oolong tea, green tea production does not involve oxidation of young tea leaves. Green tea is produced from steaming fresh leaves at high temperatures, thereby inactivating the oxidizing enzymes and leaving the polyphenol content intact. Various extraction methods have been reported in the literature like microwave extraction, ultrasonic extraction, Soxhlet extraction, heat reflux extraction and ultrahigh pressure extraction for extraction of polyphenols from green tea. Caffeine may be excluded in green tea extracts in order to avoid side effects ; caffeine free green tea extract supplements are now available.1 The cardinal antioxidative ingredient in the green tea extract is green tea catechins (GTC), which comprise four major epicatechins derivative; namely, epicatechin(EC),epigallocatechin(EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG). Other components include three kinds of flavonoids, known as kaempferol, quercetin, and myricetin. 2 A remarkably higher content of myricetin is detected in tea and its extracts than in many other plants, and this high concentration of myricetin may have some implications with the bioactivity of tea and its extracts.3