黄芩苷对变异链球菌UA159体外的抑制作用

目的探讨黄芩苷对变异链球菌国际标准株UA159的体外抑制作用。方法采用液体倍比稀释法结合酶标仪测OD600值测定黄芩苷对变异链球菌UA159的最低抑菌浓度(minimum inhibitory concentration,MIC)。利用酶标仪测定不同浓度的黄芩苷药液中变异链球菌UA159的OD600值,绘制生长曲线;计算黏附率及黏附抑制率;用结晶紫定量法测定黄芩苷对变异链球菌UA159生物膜形成的影响;用扫描电镜观察黄芩苷对变异链球菌UA159细菌总量的影响。结果黄芩苷对变异链球菌UA159最低抑菌浓度为12 mg/mL;随着黄芩苷药液浓度的增加,变异链球菌UA159生长速度缓慢,并且其黏附率下降,黏附抑制率增加(P<0.05)。结晶紫定量法结果显示,与菌液组相比,0、6、12 h时加入黄芩苷药液变异链球菌UA159生物膜形成量显著降低(P<0.001)。扫描电子显微镜下,0、6、12 h时加入黄芩苷后细菌总量均明显下降。结论黄芩苷能够抑制体外变异链球菌UA159的生长繁殖;同时其对变异链球菌UA159的黏附、生物膜形成均有抑制作用。

Inhibitory effect of baicalin on Streptococcus mutans UA159 in vitro

Objective To investigate the inhibitory effect of baicalin on Streptococcus mutans UA159 in vitro.Methods The minimum inhibitory concentration(MIC)of baicalin on Streptococcus mutans UA159 was determined by the liquid multiple dilution method combined with the OD600 value measured by microplate.The OD600 value of Streptococcus mutans UA159 in different concentrations of baicalin was measured by an enzyme mapping instrument.A growth curve was drawn,and the adhesion rate and adhesion inhibition rate were calculated.The effect of baicalin on the formation of Streptococcus mutans UA159 biofilms was observed by the crystal violet quantitative method and scanning electron microscopy.The effect of baicalin on the total number of Streptococcus mutans UA159 bacteria was observed by scanning electron microscopy.Results The MIC of baicalin on Streptococcus mutans UA159 was 12 mg/mL.With increasing baicalin concentration,the growth rate of Streptococcus mutans UA159 was slowed,the adhesion rate of Streptococcus mutans UA159 decreased and the adhesion inhibition rate increased(P<0.05).The results of crystal violet quantitative method showed that compared with the bacterial control group,the biofilm formation of Streptococcus mutans UA159 was significantly reduced after adding baicalin at 0 h,6 h and 12 h(P<0.001).Under a scanning electron microscope,the total number of bacteria decreased significantly after adding baicalin at 0 h,6 h and 12 h.Conclusion Baicalin can inhibit the growth and reproduction of Streptococcus mutans UA159 in vitro as well as the adhesion and biofilm formation of Streptococcus mutans UA159.