杜仲板皮多糖的超声波辅助提取及脱色工艺

Ultrasonic-assisted extraction and decolorization of polysaccharides from the bark of Eucommia ulmoides Oliver.

以杜仲板皮为试材,用超声波辅助提取其多糖。以多糖提取率为评价指标,在单因素试验的基础上,通过正交试验对杜仲板皮多糖提取工艺进行优化;以脱色率和多糖保留率为考察指标,利用正交试验优化活性炭脱除杜仲板皮多糖中色素的工艺。结果表明,杜仲板皮多糖的较佳提取工艺为:液料比30∶1(mL∶g),超声温度50℃,超声功率400W,超声时间30min。在此条件下,杜仲板皮多糖的平均提取率为2.16%,相对标准偏差(RSD)为1.86%。杜仲板皮多糖活性炭法脱色的较优组合为:活性炭用量0.6%(m/m),脱色温度60℃,脱色时间50min,脱色溶液pH=5.0。在此条件下进行脱色处理,平均脱色率为76.20%,RSD为2.46%;多糖平均保留率为62.68%,RSD为2.35%。

The polysaccharides from the bark of Eucommia ulmoides Oliver. were extracted by ultrasonic- assisted extraction. With the extraction rate of polysaccharides as the evaluation index, on the basis of single factor experiment, the extraction process of polysaccharides from the bark of Eucommia ulmoides Oliver. was optimized by orthogonal test;with the decolorization rate and the retention rate of polysaccharides as the evaluation indexes, the process of removing pigment in the polysaccharides extracted from the bark of Eucommia ulmoides Oliver. by activated carbon was optimized by orthogonal test. The results showed the optimum extraction technology of polysaccharides from the bark of Eucommia ulmoides Oliver., in which the liquid-solid ratio was 30∶1(mL∶g), the ultrasonic temperature was 50 ℃, the ultrasonic power was 400 W, and the ultrasonic time was 30 min. Under these conditions, the average extraction rate of polysaccharides from the bark of Eucommia ulmoides Oliver. is 2.16%, and the relative standard deviation(RSD)is 1.86%. The optimum conditions for decolorization of polysaccharides from the bark of Eucommia ulmoides Oliver. by activated carbon method are as follows: the dosage of activated carbon is 0.60%(m/m), the decolorization temperature is 60 ℃, the decolorization time is 50 min, and the pH of decolorization solution is 5.0. Under these conditions, the average decolorization rate is 76.20%, and the RSD is 2.46%;the average retention rate of polysaccharides is 62.68%, and the RSD is 2.35%.