芦笋老茎多糖体外抗氧化及降血糖作用研究

以芦笋老茎为原料,经提取、分离纯化获得芦笋老茎多糖,对不同浓度芦笋老茎多糖的DPPH·清除能力、·OH清除能力、还原能力、α-葡萄糖苷酶抑制率、α-淀粉酶抑制率等抗氧化及降血糖活性指标进行了研究。结果表明:在一定浓度范围内,随着芦笋老茎多糖浓度的增大,其对DPPH·的清除率呈逐渐上升趋势,存在一定的浓度依赖性;当浓度为3 mg/mL时,芦笋老茎多糖对DPPH自由基的清除率可达73.37%,与相同浓度的Vc清除率的差值约为20%。随着浓度的增加,芦笋老茎多糖对·OH清除率呈先上升后逐渐趋于平稳趋势,当浓度为1.5 mg/mL时,清除率可达90.56%,随后增速放缓;且当浓度低于1.5 mg/mL时,清除能力明显弱于Vc,高于1.5 mg/mL时,清除能力逐渐接近Vc。随着浓度的增加,芦笋老茎多糖的还原能力呈逐渐上升趋势,存在一定的浓度依赖性,且在相同浓度下,芦笋老茎多糖的还原能力要明显弱于Vc。在一定浓度范围内,芦笋老茎多糖对α-葡萄糖苷酶和α-淀粉酶的抑制率整体上存在一定的浓度依赖性,随着多糖浓度的增加,抑制率呈逐渐增强随后略有降低趋势,当多糖浓度为7 mg/mL时抑制率最大,抑制率分别可达87.46%和90.91%。说明芦笋老茎多糖具有较好的体外抗氧化及降血糖作用效果,为芦笋老茎的综合利用提供一定的应用指导。

Antioxidant and Hypoglycemic Effects in Vitro of Asparagus Old Stem Polysaccharide

In this study,the old stems of asparagus were used as raw materials,and the asparagus old stem polysaccharides were obtained by extraction,separation and purification.DPPH· clearing ability,OH scavenging ability,reducing ability and α-glucosidase inhibition rate of stem polysaccharides of different concentrations of asparagus were observed.Antioxidation and hypoglycemic activity indicators such as α-amylase inhibition rate were studied.The results showed that within a certain concentration range,with the increase of the concentration of old stem polysaccharides,the clearance rate of DPPH· increased gradually,and there was a certain concentration dependence.When the concentration is 3 mg/mL,the scavenging rate of DPPH free radicals by asparagus old stem polysaccharides can reach 73.37%,and the difference with Vc clearance rate at the same concentration is about 20%.With the increase of concentration,the removal rate of ·OH increased gradually and then gradually became stable.When the concentration was 1.5 mg/mL,the clearance rate reached 90.56%,and then the increasing rate slowed down.When the concentration is lower than 1.5 mg/mL,the scavenging ability is obviously weaker than Vc.When the concentration is higher than 1.5 mg/mL,the scavenging ability is closer to Vc.With the increase of concentration,the reducing ability of the old stem polysaccharide of asparagus is gradually increasing.There is a certain concentration dependence,and at the same concentration,the reducing ability of the old stem polysaccharide of asparagus is significantly weaker than Vc.In a certain concentration range,the inhibition rate of α-glucosidase and α-amylase by the old stem polysaccharide of asparagus is overall,there was a certain concentration dependence.With the increase of polysaccharide concentration,the inhibition rate increased gradually and then decreased slightly.When the concentration of polysaccharide was 7 mg/mL,the inhibition rate was the highest,and the inhibition rate was 87.46% and 90.91%,respectively.It indicated that the old stem polysaccharide of asparagus had better antioxidation and hypoglycemic effects in vitro,and provided some application guidance for the comprehensive utilization of old stems of asparagus.