Preliminary characterization and antioxidant and hypoglycemic activities in vivo of polysaccharides from Huidouba

Abstract

Here, the antioxidant and hypoglycemic activities of polysaccharides from Huidouba were preliminarily characterized. Two novel polysaccharides, HDBP-1 and HDBP-2 (127.33 kDa and 9.703 kDa, respectively), were purified by ultrafiltration using a Sephadex G-200 column and then characterized by high-performance gel permeation chromatography (HPGPC), high-performance liquid chromatography (HPLC), infrared spectroscopy (FT-IR), GC-MS, NMR and the Congo red test. HDBPs (crude Huidouba polysaccharide (CHDBP), HDBP-1 and HDBP-2) exhibited significant antioxidant and α-glucosidase inhibitory activities in vitro. In addition, in vivo hypoglycemia experiments in mice revealed that CHDBP, HDBP-1 and HDBP-2 demonstrated active roles in reversing diabetic symptoms. These polysaccharides decreased the serum triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels and significantly improved oral glucose tolerance (OGT), indicating that HDBPs suppressed obesity and alleviated insulin resistance. Moreover, HDBP-2 with lower molecular weight performed better in antioxidant capacity, α-glucosidase-inhibiting activity and hypoglycemic activity. These results suggest that HDBPs have the potential to be functional foods with hypoglycemic properties.