西藏凹乳芹多糖的分离纯化、结构表征及抗氧化活性研究OACSTPCD

A new polysaccharide was extracted from Vicatia thibetica de Boiss using an ultrasound-assisted enzymatic method.After separation and purification by DEAE-52 cellulose ion column chromatography and Sephadex G-100 glucan gel column chromatography,the water-soluble Vicatia thibetica de Boiss polysaccharide(VTP-1)was obtained.High-performance gel permeation chromatography(HPG-PC),ion chromatography,UV-vis spectrum,Fourier transform infrared spectroscopy,and Congo red experiment were applied to analyze the molecular weight,monosaccharide composition,spatial structure,physicochemical properties,and antioxidant activity in vitro of poly-saccharides.Results showed that the relative molecular weight of VTP-1 was 96.81 kDa.It was composed of arabinose,galactose,glu-cose,xylose,and mannose in the molar ratio of 5.63∶2.79∶86.36∶3.02∶1.59.VTP-1 was identified as a neutral heteropolysaccharide containing both α-and β-type glycosidic bonds and did not have a triple helix structure.The IC50 values of DPPH free radical,ABTS cat-ionic radical,and hydroxyl radical scavenging ability were 1.808,1.845,and 4.634 mg/mL,respectively,and the inhibition rates showed a dose-dependent increase,indicating that VTP-1 had good antioxidant activity in vitro.In conclusion,this experiment was the first to study the polysaccharide of Vicatia thibetica de Boiss,which proved its antioxidant activity in vitro.It could provide a theoretical basis for the application of Vicatia thibetica de Boiss polysaccharides in the functional food and medicine industry.