响应面优化博爱赤松茸多糖提取工艺及其抑菌和抗氧化活性研究

Optimization of Extraction Process of Polysaccharides from Stropharia rugosoannulata in Bo'ai County by Response Surface Method and Evalation of Their Antibacterial and Antioxidant Activity

优化博爱赤松茸多糖超声辅助提取工艺,并研究其抑菌和抗氧化活性。以多糖得率为评价指标,在单因素实验基础上,采用3因素3水平的Box-Benhnken设计优化赤松茸多糖超声辅助提取工艺;分别采用二倍稀释法和平板涂布法测定博爱赤松茸多糖提取物的最小抑菌浓度(Minium inhibitionconcentration,MIC)和最小杀菌浓度(Minimum bactericidal concentration,MBC);分别采用ABTS法和FRAP法测定博爱赤松茸多糖的抗氧化能力。结果表明:博爱赤松茸多糖超声辅助最佳提取工艺为超声温度62℃、料液比1:30(g/mL)、超声时间62 min,在此条件下,博爱赤松茸多糖的平均得率为13.25%,与理论预测值(13.35%)相对误差为0.75%。在供试的5种常见致病菌中,博爱赤松茸多糖提取物仅对鼠伤寒沙门氏菌具有较强的抑制作用,其MIC和MBC分别为6.25 mg/mL和12.5 mg/mL。博爱赤松茸多糖提取物具有较强的清除ABTS+自由基的能力和还原Fe3+的能力,且在一定质量浓度范围内呈量效关系,但均弱于相同质量浓度下的阳性对照VC。优化后的博爱赤松茸多糖超声辅助提取工艺稳定可行,且其提取物具有较强抗氧化活性和抑菌活性,但其抑菌作用具有选择性。

The ultrasonic-assisted extraction process of polysaccharides from Stropharia rugosoannulata in Bo'ai County and the antibacterial and antioxidant activities were analyzed.On the basis of single factor experiments,with the polysaccharide yield as response value,the ultrasonic-assisted extraction process of polysaccharides from Stropharia rugosoannulata in Bo'ai County was optimized using Box-Behnken experimental design with three factors and three levels.The minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of the polysaccharides extracted from Stropharia rugosoannulata in Bo'ai County were determined using the double dilution method and the plate coating method,respectively.The antioxidant activity was determined using ABTS method and FRAP methods.The results showed that the optimal ultrasonic-assisted extraction conditions were 62℃(ultrasonic temperature),1:30 g/mL(solid-liquid ratio)and 62 min(ultrasonic time).Under these conditions,the average yield of polysaccharide was 13.25%,which agreed well with the predicted value of 13.35%,the relative error was 0.75%.Among the five common pathogenic bacteria tested,the polysaccharide extract showed the strongest inhibitory effect on Salmonella typhimurium with the minimum inhibitory concentration of 6.25 mg/mL and the minimum bactericidal concentration of 12.5 mg/mL.Meanwhile,the polysaccharide extract showed strong ability to scavenge ABTS+free radicals and reduce Fe3+,and showed dose-effect relationship within a certain concentration range,although weaker than the positive control(VC)at the same concentration.The results suggested that the regression models were stable and feasible for polysaccharide extraction from Stropharia rugosoannulata in Bo'ai County and the extract had strong antioxidant and antibacterial activities,but its antibacterial effect was selective.