无患子果皮多糖微波提取工艺及抗氧化活性研究

Technology of Microwave-assisted Extraction of Sapindus Peel Polysaccharide and Its Antioxidant Activity

探讨了无患子果皮多糖的微波提取工艺和体外抗氧化能力,并对多糖结构进行了初步表征。考察了微波提取温度、时间和液料比对无患子果皮多糖得率的影响,利用响应面分析法优化微波提取工艺,确定了提取的最佳工艺参数为:温度92℃,时间26 min,液料比25∶1(mL∶g),此条件下,多糖得率达3.47%。无患子果皮多糖主要由葡萄糖、木糖、半乳糖、阿拉伯糖和果糖组成,具有典型的多糖红外光谱特征。此外,通过测定无患子果皮多糖对·OH、DPPH·的清除能力评价其抗氧化活性,无患子果皮多糖以浓度依赖性方式表现出较强的抗氧化活性,且粗多糖抗氧化活性明显高于纯化多糖,无患子果皮多糖抗氧化活性与糖蛋白结构有一定的关联性。

The microwave extraction technology and in vitro antioxidant capacity of polysaccharides from Sapindus peel were studied in this work, and the primary structure of the polysaccharide was also characterized. The effects of microwave extraction temperature, extraction time and liquid-solid ratio on the yield of polysaccharides were investigated. The microwave extraction process was optimized by response surface analysis. The results showed that the optimum extraction process conditions were as follows： extraction temperature 92 ℃, extraction time 26 min, liquid-solid ratio 25 ∶1（mL ∶g）. The maximal yield of polysaccharides reached 3.47%. Sapindus peel polysaccharide is mainly composed of glucose, xylose, galactose, arabinose and fructose, with typical polysaccharide IR characteristics. In addition, the anti-oxidative activity of polysaccharides was evaluated by the scavenging ability on hydroxyl radicals and DPPH free radicals. Sapindus peel polysaccharides showed strong antioxidant activity in a concentration-dependent manner, and the antioxidant activity of the crude polysaccharides was significantly higher than that of purified polysaccharides. The antioxidant activity of polysaccharides has a certain correlation with the glycoprotein structure.