药桑叶多糖提取工艺优化及其降血糖活性研究

采用Box-Behnken试验设计对药桑叶多糖提取条件（液料比、提取温度、提取时间）进行优化，并用对硝基苯-α-D-吡喃葡萄糖苷（p-NPG）法对药桑叶多糖进行α-葡萄糖苷酶抑制活性测定。结果显示，药桑叶粗多糖提取最佳工艺为：在液料比25∶1（mL∶g），提取温度90 ℃、提取时间3 h条件下，药桑叶粗多糖提取率最高为（13.39±0.53）%。降血糖初步研究结果为：药桑叶粗多糖对α-葡萄糖苷酶有较好的抑制活性，其半抑制浓度（IC50）为0.96 mg/mL。

Optimization of polysaccharides extraction technology from Morus nigra leaves and its hypoglycemic activity

Extraction parameters of polysaccharides from Morus nigra leaves, such as liquid-solid ratio, extraction temperature and time, was optimized with Box-Behnken experiments. The inhibition rate of polysaccharides from M. nigra leaves against α-glycosidase was measured by p-NPG method. The results showed that the polysaccharides extraction rate of M. nigra leaves was the highest of (13.39±0.53)% under the optimized conditions of extraction temperature 90 ℃, time 3 h and liquid-solid ratio 25∶1 (ml∶g). The preliminary results of hypoglycemic activity showed that the crude polysaccharides from M. nigra leaves had good hypoglycemic inhibition activity against α-glycosidase, and half maximal inhibitory concentration (IC50) was 0.96 mg/ml.