A SURVEY OF THE STUDIES ON THE EXTRACTION, PURIFICATION,COMPOSITION AND PHARMACEUTICAL EFFECTS OF TEA POLYSACCHARIDE

The methods of extraction and purification, composition and pharmacological effects of tea polysaccharide is summarized. The extraction of tea polysaccharide are affected by the crude material, the methods of subsidiary preconditioning, the conditions of abstraction and the precipitating agent. Now the crude tea polysaccharide is abstracted in water mostly. It's purified initiatively by removing protein and decoloration. For the analysis of the chemical structure of tea polysaccharide, it must be purified further by means of precipitation, ultra-filtration or column chromatography. The compositions of tea polysaccharide vary largely with the crude material and the method of isolation and purification. The tea polysaccharide has the pharmacological effects of anti-thrombosis, reducing blood sugar,lipid and blood pressure and strengthening the body's immunization function. It can be used in curing diabetes and disease of heart, brain and blood vessel as healthy foods and subsidiary medicine.