响应面优化超声辅助酶法提取北芪菇多糖及其抑菌活性研究

Optimization of ultrasonic-assisted enzymatic extraction of polysacchairides from astragali mushroom by response surface analysis and its antimicrobial activity

优化酶法辅助超声提取北芪菇多糖工艺并研究其抑菌活性。以多糖提取率为指标,采用单因素试验和响应面法对提工艺条件进行优化。并采用最低抑制浓度法考察北芪菇多糖对大肠杆菌等5种试验菌的抑制效果。结果表明,最佳提取工艺条件为:料液比1∶45,酶添加量1%,超声温度70℃,超声时间50min,超声功率200W,北芪菇多糖提取率最大为9.59%±0.16。抑菌结果表明,对大肠杆菌、枯草芽孢杆菌、金黄色葡萄球菌有抑制作用,最小抑制浓度MIC是25~50mg/mL之间,对禾谷镰刀菌有一定抑制作用,最小抑制浓度MIC是75~100mg/mL之间,对青霉和酿酒酵母无抑制作用。

In this study,optimization of zymolysis-assisted ultrasonic extraction of polysaccharide from Astragali mushroom and its antimicrobial activities in vitro were investigated. The extraction rate was used as the indicator,the extraction condition was optimized by single factor experiments and response surface methodology（RSM）. The antimicrobial activities of Astragali mushroom polysacchairides were measured by using minimum inhibiting concentration method against five microorganisms. The optimal extraction conditions were as follows ：ultrasonic temperature 70 ℃,ultrasonic time 50 min,ratio of solid to liquid 1 ∶ 45. Under the above conditions,maximum extraction rate of Astragali mushroom polysacchairides reached to 9.59%±0.16. The inhibitory effect results showed a good inhibitory effect to E.coli,Bacillus subtilis and S.aureus with a minimum inhibition concentration MIC range of 25 ~ 50 mg/mL. The minimum inhibition concentration MIC to Fusarium graminearum was 75 ~ 100 mg/mL. However,no inhibitory effect on Penicillium sp. and Saccharomyces cerevisiae was observed.