两性霉素B对假丝酵母菌与乳杆菌生物膜作用的研究

Study on the effect of amphotericin B on the biofilm of Candida and Lactobacillus

目的研究两性霉素B对假丝酵母菌与乳杆菌生物膜的作用。方法选取2022年7月至8月在首都医科大学附属北京妇产医院就诊患者阴道来源的4株假丝酵母菌及4株乳杆菌,测定其不同时期生物膜形成能力,并观察其生物膜形成情况。分别测定两性霉素B对假丝酵母菌及乳杆菌的最小抑菌浓度(MIC)及最小抑制生物膜浓度(MBIC),并在扫描电镜下观察两性霉素B对上述菌生物膜的作用。结果白假丝酵母菌及卷曲乳杆菌生物膜形成能力48 h高于24 h(P<0.05),7号乳杆菌生物膜形成能力48 h高于72 h(P<0.05)。两性霉素B对白假丝酵母菌的MIC值为0.12500μg/ml;1、3、4号假丝酵母菌在两性霉素B浓度为2μg/ml时生物膜形成能力低于阳性对照组(两性霉素B浓度为0μg/ml时)(P<0.05),均与后续各浓度差异无统计学意义(P>0.05),两性霉素B对白假丝酵母菌的MBIC值为2μg/ml。两性霉素B对卷曲乳杆菌无抑制作用;除7号乳杆菌在两性霉素B浓度为1、8、16μg/ml时生物膜形成能力高于阳性对照组(P<0.05)外,其余各卷曲乳杆菌在各浓度生物膜形成能力与阳性对照组差异无统计学意义(P>0.05)。结论白假丝酵母菌及卷曲乳杆菌在48 h生物膜形成能力最强。两性霉素B对白假丝酵母菌有较强抑菌能力,但对已形成生物膜的白假丝酵母菌需更大剂量才有破坏生物膜的作用。对卷曲乳杆菌无抑制及生物膜破坏作用。

Objective To study the effect of amphotericin B on Candida and Lactobacillus biofilm.Methods From July 2022 to August 2022,four strains of Candida and four strains of Lactobacillus from the vagina of patients in Beijing Obstetrics and Gynecology Hospital,Capital Medical University were selected to determine their biofilm formation ability at different stages and observe their biofilm formation.The minimum inhibitory concentration(MIC)and minimum biofilm inhibitory concentration(MBIC)of amphotericin B on Candida and lactobacillus were determined respectively,and the effect of amphotericin B on the biofilms was observed under scanning electron microscope.Results The biofilm formation ability of Candida and Lactobacillus at 48 h was higher than that at 24 h(P<0.05),and the biofilm formation ability of Lactobacillus No.7 at 48 h was higher than that at 72 h(P<0.05).The MIC of amphotericin B against Candida albicans was 0.12500μg/ml.When the concentration of amphotericin B was 2μg/ml,the biofilm forming ability of Candida No.1,No.3 and No.4 was lower than that of the positive control group(amphotericin B 0μg/ml)(P<0.05),and there was no difference between them and the subsequent concentrations(P>0.05),the MBIC of amphotericin B against Candida albicans was 2μg/ml.Amphotericin B had no inhibitory effect on Lactobacillus crispatus.The biofilm forming ability of Lactobacillus No.7 at concentration of 1,8,and 16μg/ml was higher than that of positive control group(P<0.05),and the other Lactobacillus crispatus had no difference in biofilm forming ability at different concentrations(P>0.05).Conclusion Candida albicans and Lactobacillus crispatus had the strongest biofilm forming ability at 48 h.Amphotericin B has strong antibacterial ability to Candida albicans,but it needs a larger dose to destroy the biofilms of Candida albicans which have formed.It has no inhibitory effect on Lactobacillus crispatus and biofilms destructive effect.