玉米须多糖的分离纯化、结构表征及降血糖活性研究OA

The effects of corn silk polysaccharide(CSPSS)wereobtained from corn silk by hot water extraction,ultrafiltration,and ethanol precipitation,and then purified by DEAE Sepharose Fast Flow column chromatography and Sephacryl S300 gel column chromatog-raphy.The chemical composition,molecular weight,monosaccharide composition,and other structures of CSPSS were analyzed by chemi-cal composition,high-performance liquid chromatography,UV-visible spectrum,infrared spectrum,nuclear magnetic resonance spec-trum,X-ray diffraction,thermogravimetric analysis,Congo red experiment,particle size potential,and scanning electron microscope.The hypoglycemic activity of CSPSS in vitro and in vivo was evaluated by the inhibition rate of CSPSS on α-glucosidase and α-amylase and the re-duction rate of blood glucose value of zebrafish with diabetes.Results showed that CSPSS was an acidic homogeneous polysaccharide,with to-tal sugar and protein content(91.60±1.06)％and(2.48±0.08)％,respectively,and molecular weight(6.88±0.28)× 104 Da.It was mainly composed of rhamnose,galacturonic acid,galactose,and xylose,with a molar ratio of 0.78∶1.08∶1.00∶2.81.Its glycosidic bond configuration was mainly beta configuration,with a small amount of alpha configuration pyranose present.It did not possess the structure of a crystalline and triple helix,mainly in the form of a sheet under electron microscopy.CSPSS had an inhibitory effect on α-glucosidase andα-amylase and exhibited a concentration-dependent manner.The half inhibitory concentration was(3.56±0.27)and(2.29±0.36)mg/mL,re-spectively.In the zebrafish model of type Ⅱ diabetes,CSPSS demonstrated significant hypoglycemic activity,reducing blood glucose levels by 19.96％and 33.63％at concentrations of 250 and 500 μg/mL,respectively.