Study on hypoglycemic mechanism of tea polysaccharide

Objective To study the hypoglycemic mechanism of tea polysaccharide.Methods The inhibitory activities of tea polysaccharide against alpha-glucosidase(EC 3.2.1.20)and alpha-amylase(EC 3.2.1.1)were tested by colorimetric method,glucose uptake into brush border membrane vehicles were determined by rapid filtration method.Results In alphaglucosidase inhibitory assay,tea polysaccharide showed potent inhibitory activity with IC₅₀ value of 3.2g/L;while inhibitory effect of tea polysacchar ide on alpha-amylase was low,the inhibitory activity were about 10% at the concentration of 1 g/L.Tea polysaccharide also significantly decreased glucose transport potency of brush border membrane vehicle of rabbit small intestine with IC₅₀ value of 15g/L.Conclusion Tea polysaccharide can inhibit alpha-g lucosidase and alpha-amylase activities and glucose uptake into br ush border membrane vehicles,therefore can delay carbohydrate dig estion and absor ption.