Therapeutic potential of epigallocatechin gallate

Abstract

Green tea leaves (Camellia sinensis, Family Theaceae) have been consumed in the form of beverage since long, but their widespread health benefits have been discovered relatively recently. Epigallocatechin gallate (EGCG) is a polyphenol found abundantly in these leaves. It is a potent antioxidant which helps greatly in combating the oxidative stress generated in the body during various physiological processes. Oxidative stress plays a great role in the development of various chronic diseases such as heart diseases, cancer, and neurodegenerative diseases, such as Parkinson’s and Alzheimer’s diseases. Oxidative stress is also involved in the process of aging. The oxygen radical absorbance capacity assay conducted by the US Department of Agriculture clearly signifies that brewed green tea is a potent antioxidant in comparison to majority of antioxidant rich foods, such as brewed black tea, raw kiwi, lemon juice, and extra virgin olive oil. EGCG has shown promising results in the therapy of various diseases and disorders such as cancers, fatty liver disease, HIV infection, hypertension, Type-II diabetes mellitus, obesity, and neurodegenerative diseases. Some recent studies have revealed novel actions of EGCG, such as interaction with proteins and phospholipids in the plasma membrane. This review presents a comprehensive outlook on the reported pharmacological activities of EGCG along with its green extraction method, pharmacokinetic and toxicity profiles. The data have been collected by several research and review papers obtained from various journal resources including PubMed Central and Elsevier.