Inhibitory Effects of Prunus mume, Coptis chinensis, and Crataegus pinnatifida on Vibrio alginolyticus and Its Biofilm In Vitro

[Objectives] To explore the inhibitory effects of Prunus mume, Coptis chinensis, and Crataegus pinnatifida on Vibrio alginolyticus and its biofilm in vitro. [Methods] The agar diffusion method was applied to determine the inhibition zone diameter of three Chinese herbal medicines on V. alginolyticus; double dilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of three Chinese herbal medicines on V. alginolyticus; methylthiazolyl tetrazolium (MTT) method was applied to evaluate the effects of three Chinese herbal medicines on the biofilm formation of V. alginolyticus. [Results] The three Chinese herbal medicines had different inhibitory effects on V. alginolyticus. The inhibition zones of P. mume, C. chinensis, and C. pinnatifida on V. alginolyticus were (18.31 ± 0.29) mm, (20.31 ± 0.30) mm, and (30.24 ± 0.14) mm respectively, and P. mume had strong bacteriostatic effects on V. alginolyticus. The double dilution method was used to determine the bacteriostatic effects of three Chinese herbal medicines on V. alginolyticus. Results showed that P. mume has the highest antibacterial and bactericidal ability. The MIC and MBC of P. mume, C. pinnatifida, and C. chinensis on V. alginolyticus was 3.91 , 31.25 , and 125 mg/mL, respectively. Finally, MTT method was applied to evaluate the effects of C. pinnatifida, C. chinensis, and P. mume on the biofilm formation of V. alginolyticus, and results showed that the MIC on the biofilm formation of V. alginolyticus was 15.63 , 7.81,and 3.91 mg/mL, respectively; the MIC of P. mume was the lowest. [Conclusions] This experiment proves that P. mume, C. chinensis, and C. pinnatifida have inhibitory effects on V. alginolyticus and its biofilm formation. It is expected to provide references for prevention and control of pathogenic vibrio induced diseases of aquatic animals.