采用超声辅助提取法分别从茯苓皮中提取多糖和三萜类物质。考察提取溶剂、超声功率、液料比、提取温度、提取时间等对茯苓皮多糖和三萜类物质的影响。结果表明，选用乙醇提取多糖，选用乙酸乙酯浸提三萜类物质，最佳提取条件为：超声功率450 W，液料比为45 mL／g，提取温度80℃，提取时间35 min。通过对DPPH自由基清除作用、还原力、羟基自由基清除作用的测定，评价茯苓皮中多糖和三萜类物质的抗氧化活性。结果表明，抗氧化能力与质量浓度存在量效关系。在质量浓度达到0.4 mg／mL时，茯苓皮多糖和三萜类物质提取液对DPPH和羟基自由基的清除能力均高于VC；茯苓皮三萜类物质提取液还原力与VC相当。茯苓皮提取物作为一种天然的抗氧化剂具有良好的应用前景。%Microwave assisted extracting conditions of polysaccharides and triterpenoids from peel of Poria cocos were studied.The in-fluence of extraction solvent , solvent-material ratio , ultrasonic power , temperature , extraction time was evaluated by single factor ex-periments.The results showed that the polysaccharides were obtained by ethanol , while the triterpenoids was obtained by ethyl acetate . The optimal conditions were as follows .Ultrasonic power 450 W;solvent-material ratio , 45 mL/g;temperature , 80℃;and extraction time, 35 min.The antioxidant activity was evaluated based on DPPH radical scavenging capacity , reducing power and hydroxyl free radical scavenging capacity .The ability of antioxidative activity was increased with the inerease concentrations of polysaccharides and triterpenoids.When extracted at the concentration of 0.4 mg/mL, polysaccharides and triterpenoids revealed relatively better DPPH radical scavenging capacity and hydroxyl free radical scavenging capacity than V C .Reducing power of riterpenoids was comparable to those of V C .Therefore , the peel of Poria cocos is effective as novel natural antioxidants .
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