黄芩苷对嗜水气单胞菌生物膜形成的影响及体内外的抑菌作用

目的] 探讨中药单体黄芩苷对嗜水气单胞菌在体内外生长及生物膜形成的影响。方法] 体外实验中，利用牛津杯法检测抑菌圈直径，结晶紫法检测生物膜的形成，通过泳动实验检测黄芩苷对嗜水气单胞菌运动性的影响，紫外吸收法检测细胞膜完整性，用透射电镜技术观察黄芩苷对细菌形态的影响。体内实验利用草鱼为对象检测黄芩苷对嗜水气单胞菌增殖的影响。结果] 黄芩苷在体外对嗜水气单胞菌有明显的抑菌效果，通过对生物膜的研究发现黄芩苷对生物膜形成具有抑制作用，并同时抑制其运动性。同时黄芩苷可以破坏细胞结构，并增加了细胞膜通透性。体内实验结果显示黄芩苷对嗜水气单胞菌具有清除作用，且具有一定的浓度依赖性。结论] 黄芩苷在体内外均具有抑制嗜水气单胞菌增殖的作用，有望在水产养殖病害防治工作中得到应用。

Bacteriostatic and antibiofilm effects of baicalin on Aeromonas hydrophila: in vitro and in vivo evaluation

Objective] To investigate the effects of baicalin, a monomer of traditional Chinese medicine on growth and biofilm formation of Aeromonas hydrophila. Methods] In vitro, antibacterial activity was determined based on the diameter of inhibition zone measured by Oxford cup method, biofilm formation was detected using the crystal violet method, bacteria motility was detected by swimming experiment. The ultraviolet (UV) absorption of the culture supernatant were measured to determine membrane integrity. Transmission electron microscopy (TEM) were performed to observe bacterial morphology. In vivo, the baicalin''s effect on the proliferation of A. hydrophila was determined in grass carps. Results] Baicalin has obvious bacteriostatic effect on A. hydrophila in vitro. The drug inhibited biofilm formation and bacterial motility. Under the action of baicalin, the cell structure was destroyed and the membrane permeability was increased. In vivo experiments showed a dose-dependent scavenging activity of baicalin on A. hydrophila. Conclusion] The results showed the inhibitory effects of baicalin on the proliferation of A. hydrophila in vitro and in vivo, suggesting the potential use of this drug to control of aquaculture diseases.