杜仲叶茯砖茶多糖提取工艺优化及抗氧化降血脂活性

Optimization of the extraction process and evaluation of antioxidant activities and hypolipidemic effects of polysaccharides from Eucommia ulmoides leaves Fu brick tea

目的:采用响应面法优化杜仲叶茯砖茶多糖提取工艺,并研究杜仲叶茯砖茶多糖的体外抗氧化降血脂活性。方法:通过单因素实验考察了提取时间、液料比、提取温度等对杜仲叶茯砖茶多糖得率的影响,在此基础上,采用响应面分析法优化提取工艺。考察了杜仲叶多糖对DPPH·,·OH,ABTS+的清除能力以及铁还原能力,并进行胆酸盐结合试验评价降血脂作用。结果:杜仲叶茯砖茶多糖最佳提取工艺如下:提取时间为1.5 h、液料比为25 m L/g、提取温度为51℃,在该最佳条件下,杜仲叶茯砖茶多糖得率为8.4769%。体外抗氧化实验结果表明,当多糖浓度为100μg/m L时,对ABTS+的清除率达98.74%;当多糖浓度为60μg/m L时,对DPPH自由基的清除率为69.28%;当多糖浓度为0.875 mg/m L时,对·OH的清除率为43.97%;当多糖浓度为0.28 mg/m L,杜仲叶茯砖茶多糖的铁还原力可达Vc的53.08%。体外降血脂实验结果表明,当多糖浓度为4.8 mg/m L时,其对牛磺胆酸盐和甘氨胆酸盐的结合率分别达到35.74%和63.77%。结论:该杜仲叶茯砖茶多糖优选提取工艺稳定可行,杜仲叶茯砖茶多糖具有较好的体外抗氧化降血脂活性。

Objective： To optimize extraction process of polysaccharides from Eucommia ulmoides leaves Fu brick tea, and evaluate its antioxidant activities and hypolipidemic effects. Method： On the basis of the effects of extraction time, liquid-solid ratio and extraction temperature on the yield of polysaccharides were investigated by single factor experiment. Response surface methodology was used to optimize the extraction process. Antioxidant activities of polysaccharides were investigated by the scavenging ability on DPPH., .OH, ABTS＋ and the reduction ability, and the combination test of sodium cholate and polysaccharides to evaluate hypolipidemic. Results： The optimum extraction process conditions were as follows： extraction time 1.5 h, ratio of liquid to solid 25 mL/g, extraction temperature 51 ℃, under the best condition, yield of polysaccharides from Eucommia ulmoides leaves Fu brick tea was 8.4769%. When the Eucommia ulmoides leaves Fu brick tea polysaccharides concentration was 100 μg/mL, the rate of scavenging ABTS＋ radicals was 98.74%. When the polysaccharides concentration was 60 μg/mL, the rate of scavenging DPPH. radicals was 69.28%. When the polysaccharides concentration was 0.875 mg/ mL, the rate of scavenging OH. radicals was 43.97%. When the polysaccharides concentration was 0.28 mg/mL, polysaccharides reduction ability up to Vc 53.08%. When the Eucommia ulmoides leaves Fu brick tea polysaccharides concentration was 4.8 mg/mL, the combination rate of sodium taurine sodium cholate and sodium glycine sodium cholate respectively reached to 35.74% and 63.77%. Conclusion： The optimum extraction process is stable and feasible, and the Eucommia ulmoides leaves Fu brick tea polysaccharides have good antioxidant activities and hypolipidemic.