新疆藁本多糖提取、理化性质与生物活性研究

Study on Extraction physicochemical properties and activity of polysaccharide from Conioselinum vaginatium

摘要:

为研究新疆藁本多糖最佳提取工艺、理化性质和抗氧化、降糖活性,采用超声辅助1-乙基-3甲基咪唑溴盐(离子液)对新疆藁本多糖进行提取,单因素和响应面实验优化多糖最佳提取工艺。对新疆藁本多糖经除蛋白、色素和小分子等杂质后的粗多糖(CV-1),进行初步的理化性质研究。通过ABTS自由基清除率和羟基自由基清除率评价CV-1体外抗氧化能力,通过α-葡萄糖苷酶、α-淀粉酶抑制率评价 CV-1体外降糖能力。结果表明:CV-1最佳提取工艺为:超声时间115 min、酶解时间90 min、超声温度55 ℃、离子液质量浓度4 g/L、料液比1:50、果胶酶质量分数0.6 %,此条件下 CV-1提取量为(125.278 ± 0.707 mg/g)。CV-1重均相对分子质量为17.57 KDa,主要由5种糖残基(甘露糖、葡萄糖、鼠李糖、阿拉伯糖、岩藻糖,摩尔百分比为5.94 %、6.8 %、28.03 %、18.4 %、40.83 %)组成,是无定形与晶体结构共存的具有三螺旋构象的α-构型糖苷,且不含有蛋白质和糖醛酸,CV-1具有优异的热稳定性,扫描电镜发现 CV-1呈片状结构,局部表面平整。对ABTS自由基、羟基自由基半清除浓度(IC50)分别为1.122 mg/mL、1.373 mg/mL,对α-葡萄糖苷酶和α-淀粉酶IC50为14.799 mg/mL、15.739 mg/mL。

Abstract:

In order to study the optimal extraction process, physicochemical properties and antioxidant and hypoglycemic activities of Conioselinum vaginatium,ultrasound-assisted extraction of Conioselinum vaginatium was carried out using 1-ethyl-3methylimidazole bromide (ionic liquid), and the optimal extraction process of polysaccharides was optimized by single-factor and response surface experiments. The crude polysaccharide (CV-1) of Conioselinum vaginatium after removing impurities such as protein, pigment and small molecules, was subjected to preliminary physicochemical property studies.The in vitro antioxidant capacity of CV-1 was evaluated by ABTS radical scavenging and hydroxyl radical scavenging, and the in vitro hypoglycemic capacity of CV-1 was evaluated by α-glucosidase and α-amylase inhibition. The results showed that the optimal extraction process of CV-1 was as follows: sonication time of 115 min, enzyme digestion time of 90 min, sonication temperature of 55 ℃, ionic liquid mass concentration of 4 g/L, material-liquid ratio of 1:50, and mass fraction of pectinase of 0.6 %, and the amount of CV-1 extracted under these conditions was (125.278 ± 0.707 mg/g).The weighted relative molecular mass of CV-1 was 17.57 CV-1 has a gravimetric relative molecular mass of 17.57 KDa, and is mainly composed of five sugar residues (mannose, glucose, rhamnose, arabinose, fucose, molar percentages of 5.94 %, 6.8 %, 28.03 %, 18.4 %, 40.83 %), is a triple-helical conformational α-constituent glycoside coexisting in an amorphous and crystalline structure, and does not contain proteins and glucuronic acid, and has an excellent thermal stability, and has an excellent thermal stability.Scanning electron microscopy revealed that CV-1 has a lamellar structure with locally flat surfaces.The half-scavenging concentrations (IC50) for ABTS radical and hydroxyl radical were 1.122 mg/mL and 1.373 mg/mL, respectively, and the IC50 for α-glucosidase and α-amylase were 14.799 mg/mL and 15.739 mg/mL.
Keywords:Conioselinum vaginatium polysaccharide; chemicalcomposition; physico chemical; antio-xidant activity; hypoglycemic activity