拟小叶喇叭藻和喇叭藻多糖对α-葡萄糖苷酶活性的影响

Theα-glucosidase inhibitory effects of polysaccharides from Turbinaria conoides and Turbinaria ornata

目的研究喇叭藻多糖对α-葡萄糖苷酶抑制活性。方法采用热水提取从拟小叶喇叭藻(Turbinaria conoides)和喇叭藻(Turbinaria ornata)中获得水溶性多糖TCP和TOP,并采用硫酸-苯酚法测定其总糖含量;用改良的咔唑法测定其糖醛酸含量;用Folin-酚法(Lowry法)测定其蛋白含量;用高效液相色谱法(HPLC)测定其单糖组成;用离子色谱法(IC)测定其硫酸根含量;用高效凝胶渗透色谱与多角度激光散射仪联用法(HPGPC-MALLS)测定其平均分子量;用PNPG显色法测定TCP和TOP对α-葡萄糖苷酶抑制活性。结果 TCP和TOP具有良好的α-葡萄糖苷酶抑制活性,IC50值分别为204.1和113.2μg·mL^(-1),效果优于阿卡波糖(220.3μg·mL^(-1))。初步动力学研究表明其均为混合型抑制方式。结论热水提取自拟小叶喇叭藻和喇叭藻的多糖具有良好的α-葡萄糖苷酶抑制活性。

Objective To study theα-glucosidase inhibitory activities of the polysaccharides fromTurbinaria conoides and Turbinaria ornata.Methods Two polysaccharides,namely TCP and TOP,were obtained with hot-water extraction.The contents of total sugar,uronic acid,protein,monosaccharide and sulfate were determined by sulfuric acid-phenol method,modified carbazole method,Lowry assay,high performance liquid chromatography（HPLC）and ion chromatography（IC）,respectively.Meanwhile,the average molecular weights（Mw）andα-glucosidase inhibitory activities of TCP and TOP were analyzed by HPGPC-MALLS and PNPG methods.Results TCP and TOP showed potent inhibitory effects onα-glucosidase with the IC50 values of 204.1and 113.2μg·mL^（-1） respectively,which were better than those of acarbose（220.3μg·mL^（-1））.Preliminary kinetic study exhibited that theα-glucosidase inhibitions were both in mixed-type manner.Conclusion Two polysaccharides extracted with hot water from Turbinaria conoides and Turbinaria ornata possessed goodα-glucosidase inhibitory activities.