半枝莲水提液体外抑菌及抑菌稳定性研究

目的 探究半枝莲水提液对大肠埃希菌、金黄色葡萄球菌、铜绿假单胞菌、耻垢分枝杆菌的体外抑菌活性及抑菌稳定性，为临床应用及开发植源性抑菌药物提供研究基础。方法 采用纸片扩散法测定半枝莲水提液对供试菌的抑菌活性，琼脂稀释法测定其最小抑菌浓度（minimum inhibitory concentration，MIC）；同时以抑菌圈直径为指标，探究盐浓度、紫外光照射和不同pH对半枝莲水提液抑菌稳定性的影响。结果 半枝莲水提液对4种供试菌有抑菌活性，抑菌圈直径分别为（18.27±0.25）、（18.0±0.50）、（17.7±0.26）、（18.0±0.00）mm，为高度敏感，MICs分别为5.41、6.08、6.08、5.41mg/ml。抑菌稳定性实验结果表明，盐浓度、紫外光照射、pH对半枝莲水提液体外抑菌活性均无显著影响（P>0.05），抑菌活性保留率均>95.0%。结论 半枝莲水提液对4种供试菌有良好的体外抑菌活性和抑菌稳定性。

Study on antibacterial activity and stability of Scutellaria barbata aqueous extract in vitro

Objective To explore the antibacterial activity and stability of Scutellaria barbata aqueous extract on Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Mycobacterium smegmatis in vitro. It provides the research basis for clinical application and the development of phyto-bacteriostatic drugs. Methods The antibacterial activity of Scutellaria barbata aqueous extract was determined by the disk diffusion method, and the minimum inhibitory concentration (MIC) was determined by the agar dilution method. At the same time, the diameter of the inhibition zone was taken as an indication, and the effects of salt concentration, ultraviolet irradiation and different pH on the antibacterial activity of Scutellaria barbata aqueous extract were investigated. Results The Scutellaria barbata aqueous extract had antibacterial activity against the four tested bacteria. The diameter of the inhibition zone was (18.27±0.25), (18.0±0.50), (17.7±0.26), and (18.0±0.00) mm respectively, which were highly sensitive, and the MICs were 5.41, 6.08, 6.08, 5.41mg/ml respectively. The results of the bacteriostatic stability test showed, Salt concentration, UV irradiation and pH had no significant effect (P>0.05) on the external antibacterial activity of the aqueous extract, and the retention rates of antibacterial activity were greater than 95.0%. Conclusion The Scutellaria barbata aqueous extract showed good antibacterial activity and stability in vitro against the four tested bacteria.