桑叶多糖提取及抑菌实验研究

Extraction and Antibacterial Experiment Research of Polysaccharide From Mulberry Leaves

以超声波辅助水提醇沉法提取桑叶多糖,采用正交实验法优化桑叶多糖的提取工艺;采用滤纸片法进行抑菌试验评价桑叶多糖体外抑菌作用。实验考察提取时间、液固比、提取温度等因素对桑叶多糖提取率的影响,观察桑叶醇提物和桑叶多糖对枯草芽孢杆菌、大肠杆菌抑制作用。实验结果证明:超声波提取时间50 min,液固比40:1(m L.g^(-1)),提取温度为70℃,其桑叶浸提液中的多糖得率达到5.50%,体外抑菌实验结果显示桑叶醇提物对枯草芽孢杆菌、大肠杆菌有明显的抑制作用,桑叶多糖对这两种菌则没有抑制作用。

The polysaccharides from mulberry leaf were extracted by water and precipitated by alcohol with the help of ultrasonic. The extraction process of polysaccharides from mulberry leaves was optimized by orthogonal experimental method and the antibacterial effect of mulberry polysaccharide in vitro was evaluated by the filter paper method. The effects of extraction time,liquid-solid ratio and extraction temperature were investigated on the extraction rate of polysaccharide from mulberry leaves. The inhibitory effects of mulberry polysaccharide on Bacillus subtilis and Escherichia coli were observed.The experimental results show that the ultrasonic extraction time was 50min; liquid-solid ratio was 40∶ 1; extraction temperature was 70℃; and the extraction of mulberry leaf polysaccharide liquid yield reached 5. 50%. The ethanolic extract from Mulberry leaves had obvious inhibitory effect on Bacillus subtilis and Escherichia coli. The polysaccharides of Mulberry leaves have no inhibitory effect on Bacillus subtilis and Escherichia coli.