Molecular characterization and hypoglycemic activity of a novel water-soluble polysaccharide from tea (Camellia sinensis) flower

Two water-soluble polysaccharide fractions, coded as TFP-1 and TFP-2, were isolated from tea (Camellia sinensis) flower and further characterized using Ubbelohde viscometer, laser light scattering, particle size analyzer and thermo-gravimetric analyzer. Meanwhile, the intrinsic viscosities, weight-average molar mass, gyration radius and hydrodynamic radius for TFP-1 and TFP-2 were shown as follows: [eta] = 0.767 and 0.207 dL/g, M-w = 15.9 x 10(4) and 1.12 x 10(4) g/mol, R-g = 37.2 and 14.1 nm, R-h = 44.8 and 14.4 nm. Moreover, the shape-factor suggested the molecule morphology adopted a branched spherical shape in NaCl solution and the typical thermal behaviors of TFP-1 and TFP-2 were presented in analysis curves. Furthermore, research also presented the inhibitory effects against alpha-glucosidase and alpha-amylase. Moreover. continuous administration of TFP-2 with 75, 150 and 300 mg/kg/b.wt for 3 weeks caused a significant (p < 0.01) decrease in blood glucose levels of alloxan-induced diabetic mice. The results concluded that TFP-2 should be considered as a potential candidate for new antidiabetic agent. (C) 2011 Elsevier Ltd. All rights reserved.