连翘苷的提取工艺优化及其抑菌活性

本研究以连翘叶为原料,采用超声辅助半仿生法提取连翘苷,在单因素实验的基础上,设计四因素三水平的响应面试验,确定最佳提取工艺条件。通过滤纸片法测定其抑菌活性,并研究了温度、p H以及紫外对连翘苷抑菌保持率的影响。方差分析结果表明:回归模型较好的反映了连翘苷得率与乙醇体积分数、液料比、提取温度以及提取时间之间的关系,得到最佳提取工艺条件:乙醇体积分数为40%,液料比为36:1(m L/g),提取温度为48℃,提取时间为100 min。在此工艺条件下,连翘苷得率为4.42%,高于其他提取方法。抑菌活性试验表明连翘苷对金黄色葡萄球菌、大肠杆菌、沙门氏菌和枯草芽孢杆菌均有抑制作用,对四种供试菌种的抑菌圈直径分别为8.33、9.85、8.85、和8.81mm。高温以及强酸、强碱会减弱连翘苷的抑菌效果,而紫外对连翘苷的抑菌效果基本没有影响。

Optimization of Extraction Process of Phillyrin and Its Antibacterial Activity

Forsythia suspensa leaves were used as raw materials for phillyrin extraction by ultrasonic assisted semi-bionic method. According to the results of one-factor-at-a-time method, a four-factor and three-level response surface methodology was applied with ethanol concentration, liquid-to-solid ratio, extraction time, temperature as influencing factors. The antibacterial activity was determined by the filter paper method, and the effects of temperature, pH and UV on the antibacterial retention rate of phillyin were studied. The results of variance analysis showed that the regression model better reflected the relationship between the yield of phillyrin and ethanol concentration, liquid-to-solid ratio, extraction time, temperature. The optimum extraction conditions were obtained: the ethanol concentration was 40%, the liquid-to-liquid ratio was 36:1, the extraction temperature was 48 °C and the extraction time was 100 min. Under these condition, the yield of phillyrin reached 4.42%, which was higher than other extraction methods. Antibacterial activity test showed that phillyrin could inhibit Staphylococcus aureus, Escherichia coli, Salmonella and Bacillus subtilis. In addition, the diameters of inhibition zone of the four tested strains were 8.33, 9.85, 8.85, and 8.81 mm respectively. The high temperature, strong acid and strong base could weaken the antibacterial effect of phillyrin, while UV had little effect on the antibacterial effect of phillyrin.