虎尾草多糖提取工艺优化及其抗氧化研究

Optimization of Extraction Process of Polysaccharide from Chloris virgata and Its Antioxidant Activity

为确定虎尾草多糖的超声协同蜗牛酶辅助提取工艺及其对油脂的抗氧化活性,以虎尾草为原料、多糖提取率为指标,设计超声协同蜗牛酶辅助提取虎尾草多糖工艺的单因素试验;在确定单因素的最佳取值范围后,利用响应面法进行优化,确定了最佳的提取工艺,进一步采用红外光谱(FTIR)对多糖的结构进行分析;最后探讨了虎尾草多糖对油脂的抗氧化活性。结果表明:虎尾草多糖的最佳提取工艺为:超声温度52℃、酶用量1.4%,超声时间41 min和pH 5.1,得到虎尾草多糖提取率为85.12 mg/g,与多糖最大提取率预测值的相对误差为0.83%,说明该回归方程误差小,准确性好。红外光谱表明:所提取的物质具有多糖的基本特征。油脂抗氧化表明:虎尾草多糖对植物油脂和动物油脂均表现出一定的脂质抗氧化作用,其用量与油脂的过氧化值呈现出负向的量效关系,说明虎尾草多糖可作为提高油脂产品货架期的添加剂。

The aim of this experiment was to determine the ultrasonic synergistic snailase assisted extraction process of polysaccharide from Chloris virgata and its antioxidant activity to oil.A single factor experiment was designed to determine the ultrasonic synergistic snailase assisted extraction process of polysaccharide from Chloris virgata with the polysaccharide extraction yield as the index.After determining the optimal value range of the single factor,the response surface methodology was used to optimize and determine the optimal extraction process.The structure of polysaccharide was further analyzed by infrared spectroscopy(FTIR).Finally,the antioxidant activity of Chloris virgata polysaccharide on oil was detectet.The results showed that the optimal extraction process of polysaccharide from Chloris virgata was as follows:ultrasonic temperature 52℃,enzyme dosage 1.4%,ultrasonic time 41 min and pH 5.1.The extraction yield of polysaccharide from the Chloris virgata was 85.12 mg/g,and the relative error with the predicted maximum extraction yield of polysaccharide was 0.83%,indicating that the regression equation had small error and good accuracy.The FTIR spectra showed that the extracted substance had the basic characteristics of polysaccharides.The lipid antioxidation showed that the polysaccharide of Chloris virgata had a certain lipid antioxidation effect on both plant oil and animal oil,and its dosage showed a negative dose effect relationship with the peroxide value of oil,indicating that the polysaccharide of Chloris virgata could be used as an additive to extend the storage time of oil products.