3种乔木树皮及枝叶提取物体外抑菌活性分析

【目的】研究槐树皮及枝叶、落叶松树皮及枝叶和水杉树皮的不同极性提取物的体外抑菌活性。【方法】分别采用水和95％乙醇进行回流提取获得10种提取物，采用试管稀释法对大肠埃希菌、金黄色葡萄球菌和肠炎沙门菌进行体外抑菌活性测试。【结果】乙醇提取物抑菌作用普遍优于水提取物，槐树皮的乙醇提取物抑菌活性最强，对以上3种细菌的最低抑菌浓度分别为31．3、15．7、62．5μg／ml。【结论】槐树皮的乙醇提取物具有较强的抑菌作用。

In vitro antibacterial effects of different polar extracts of barks and branches from three arbors

Objective] To study the inhibitory activities of different extracts from the barks and branches of Sophora japonica Linn, Larix gmelinii Rupr, and the barks of Metasequoia glyptostroboides Hu and Cheng on three bacterial strains. Methods ] The barks and branches from 3 arbors were extracted by circumfluence with two different polar solvents （water or 95% ethanol）, respectively. Antibacterial effects of different extracts on Eschcrichia coli, Staphylococcus aureus, and Salmonella enteritidis were determined by tube dilution method. Results] The antibacterial effects of ethanol extracts were generally better than that of the water extracts. The minimum inhibitory concentrations of the ethanol extracts from the bark of Sophora japonica Linn. against the three strains were 31.3 μg/ ml, 15.7 μg/ml, and 62.5 μg/ml respectively, showed the highest antibacterial activities. Conclusion] The extracts of the barks of Sophora japonica Linn. have as better antibacterial effects than the other two.