Much attention has been focused on natural polysaccharides because of its multiple bioactivities, pharmacological activities and safety. The conformation of polysaccharides has stronger effects on bioactivities according to the recent studies. Tea, which is the most popular beverage in the world, was studied in this paper. Tea polysaccharides (TPS) fractions were isolated and purified from low-grade green tea. And the physico-chemical properties and the chemical structure of TPS fractions were in...