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

Abstract:

[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.