响应曲面法优化撕裂蜡孔菌多糖的微波辅助提取工艺及抗氧化活性研究

Abstract

本论文以实验室自行筛选并鉴定的一株撕裂蜡孔菌为材料，以多糖得率为评价指标，在单因素试验的基础上，利用响应曲面法的中心组合设计，对菌丝体多糖的微波辅助提取工艺进行优化，并对多糖的体外抗氧化活性进行了研究。结果表明：以水为浸提溶剂，微波辅助提取多糖的最优条件为微波时间30 s、微波功率480 W、液料比1:20、浸提时间30 min、浸提温度35℃。在此条件下菌丝体多糖得率预测值为6.523%，实测值为6.437%。体外抗氧化试验结果证实菌丝体多糖具有一定的抗氧化活性，抗氧化能力与浓度间有很好的量效关系，浓度越大，抗氧化能力越强。其中菌丝体多糖的抗脂质过氧化能力和清除超氧阴离子自由基能力较强，对羟自由基和过氧化氢的清除效果较好，但还原能力较弱。撕裂蜡孔菌菌丝体多糖具有天然的抗氧化能力，在开发多糖类天然抗氧化剂用品方面具有一定的现实意义。 Crude polysaccharides were analyzed from the mycelium of Ceriporia lacerate isolated and identified in our laboratory. According to the single-factor experiments, response surface methodology (RSM) based on a central composite design (CCD) was applied for the optimization of microwave-assisted extraction process. The antioxidant activities of crude polysaccharides were also detected in this paper. The test results indicated that the optimum extraction conditions were obtained as follows: microwave time 30 s, microwave power 480 W, ratio of sample to water 1:20, extract time 30 min and extract temperature 35˚C. Under these conditions, the predictive and verified values of maximal yield of polysaccharides were 6.523% and 6.437%, respectively. Crude polysaccharides from the mycelium of Ceriporia lacerate showed a certain amount of antioxidant activity. The antioxidant capacity of polysaccharide and its concentration had good dose-effect relationship. With the increase of concentration, the antioxidant activities became stronger. Crude polysaccharides had strong anti-lipid peroxidation and scavenging superoxide anion radical effects, but weak in reducing effects. At the same time, scavenging effects of hydroxyl free radicals and hydrogen peroxide were also good. Crude polysaccharides from the mycelium of Ceriporia lacerate had natural antioxidant capacity, and had some realistic practical significance to develop multi-functional antioxidant products.