响应曲面法优化玉竹水溶性多糖提取及体外抗氧化研究

Optimization of Water-Soluble Polysaccharides Extraction from Rhizome of Polygonatum odoratum Using Response Surface Methodology and Its Antioxidant Activities in Vitro

采用响应曲面法优化玉竹(Polygonatum odoratum(Mill.)Druce)水溶性多糖(POP)提取的工艺条件。在单因素试验基础上选取液料比、提取温度和提取时间3个关键影响因子,以POP提取率为响应值,依据回归分析确定POP最佳提取条件为:液料比为35∶1 mL/g,提取温度为88.35℃,提取时间为2.24 h,POP的提取率理论预测值为8.47%。在修正条件下,POP的实际提取率可达(8.46±0.02)%。POP对DPPH.、.OH和O2-.自由基均有一定的清除活性,相比之下对H2O2清除活性尤其明显,而且POP清除H2O2的IC50值为0.541 mg/mL,小于VC的IC50值(0.901 mg/mL)。

A Box-Behnken design was used to optimize the extraction conditions of waler-soluble polysaccharides （POP） from Polygonatum odoratum （Mill.） Druce. Three factors such as extraction time （h）,extraction temperature （RE） and ratio of water to raw material were investigated. The experimental data were fitted to a second-order polynomial equation using muhiple regression analysis and also examined using the appropriate statistical methods. The optinmm extraction conditions were listed as follows：extraction time 2.24 h,temperature 88.35 ℃ ,and ratio of water to raw material 35：1 mL/g,the predicted yield of polysaeeharides extracted was 8.47%. Under the optimum conditions,the mean extraction yield of polysaccharides was （8.46±0.02）. The antioxidant in vitro results showed that the inhibition effects of POP on 2,2-diphenyl-2-picrylhydrazyl free radical, hydroxyl free radical and superoxide anion radical with IC50 values were 0.646,10.029,0.2dl mg/mL,respectively,which were higher than 0.048,0.238,0.078 mg/mL of ascorbic acid,respectively. POP showed significant inhibitory effects on hydrogen peroxide with IC50 value of 0.541 mg/mL,which was lower than 0.901 mg/mL of ascorbic acid.