玉竹多糖低共熔溶剂提取工艺优化及其抗氧化和抗糖基化活性研究

Optimization of extraction process of Polygonatum odoratum polysaccharide by deep eutectic solvent and its antioxidant and anti glycosylation activities

为提高玉竹多糖提取率,采用响应面分析法优化低共熔溶剂(deep eutectic solvents,DESs)提取玉竹多糖的工艺,通过DPPH自由基、ABTS阳离子自由基的清除率和氧化自由基吸收能力(oxygen radical absorbance capacity,ORAC)法评价低共熔溶剂提取的玉竹多糖(Polygonatum odoratum polysaccharide extracted by deep eutectic solvents,DPoP)体外抗氧化活性,通过荧光分光光度法测定DPoP对体外非酶糖基化体系中晚期糖基化终产物(advanced glycation end products,AGEs)形成的抑制能力。结果表明,DESs提取法是一种高效的提取玉竹多糖的方法,尿素-氯化胆碱为供试方案中提取率最高的DESs组合,其优化的工艺参数为:尿素-氯化胆碱摩尔比3∶1,提取温度92℃,提取时间41 min,含水量19%,液料比29∶1。此条件下的多糖提取率达到(29.03±0.54)%,是热水浸提法的4.67倍。DPoP对DPPH自由基、ABTS阳离子自由基清除率随质量浓度增加而增加,在质量浓度为20 mg/mL时,清除率分别达到(17.97±0.47)%、(40.69±0.34)%,ORAC值达到(121.67±3.65)μmol/g;DPoP对糖基化终末产物AGEs相对抑制率达到(87.63±0.66)%。该研究为玉竹多糖的开发利用提供理论性指导,同时在植物活性成分提取方面也具有一定的意义。

In order to improve the extraction rate of Polygonatum odoratum polysaccharide, the extraction process of Polygonatum odoratum polysaccharide with deep eutectic solvents was optimized by response surface methodology. The antioxidant activity of Polygonatum odoratum polysaccharide extracted by deep eutectic solvents(DPoP) was evaluated by DPPH radical scavenging rate, ABTS cationic radical scavenging rate and ORAC methods, and the inhibitory ability of DPoP on the formation of advanced glycation end products(AGES) in non-enzymatic glycation system in vitro was determined by fluorescence spectrophotometry. The results showed that DESs extraction method was an efficient method for extracting Polygonatum odoratum polysaccharide. Urea-choline chloride was the best combination of DESs in the test scheme, and the optimum process parameters for Polygonatum odoratum polysaccharide extracted by DESs were as follows: The urea-choline chloride molar ratio was 3∶1 with extraction temperature at 92 ℃ for 41 min;water content was 19% and liquid-material ratio was 29∶1. Under this condition, the extraction rate of Polygonatum odoratum polysaccharide reached(29.03±0.54)%, which was 4.67 times higher than that extracted by the traditional hot water. The scavenging rates of DPPH radical and ABTS cationic radical by DPoP increased with the increase of mass concentration. When the mass concentration was 20 mg/mL, the scavenging rates reached(17.97±0.47)%,(40.69±0.34)% respectively, and ORAC value reached(121.67±3.65) μmol/g. This study not only provides theoretical guidance for the development and utilization of Polygonatum odoratum polysaccharide, but also has certain significance in the extraction of plant active components.