两性霉素B与人参茎叶皂苷联合抗念珠菌生物膜作用的研究

Effect of amphotericin B combined with ginseng stem-leaf saponins against Candida biofilms

目的探讨人参茎叶皂苷(Ginseng stem-leaf saponins,GSLS)联合两性霉素B(amphotericin B,AMB)对念珠菌生物膜的体外抑制活性。方法采用ITS及β-tubulin基因部分测序对临床分离的31株经形态学鉴定为念珠菌菌株进行分子鉴定;按照美国标准化实验室与研究所(CLSI)推荐的M27-A3微量液基稀释法对收集的临床菌株及标准菌株进行体外抗念珠菌生物膜联合药敏试验;使用甲基四氮盐(XTT)减低法和结晶紫分光光度法分别对生物膜的活性和生物膜总量测定。结果 31株临床念珠菌中,其中白念珠菌16株、近平滑念珠菌6株、热带念珠菌8株、季也蒙念珠菌1株。两性霉素B联合人参茎叶皂苷对所有试验菌株的FICI值均小于等于0. 5(FICI≤0. 5)。相对于单独用药,二者联合能更有效地抑制菌株生物膜的形成和活力,单药与两药联合的生物膜形成量的差异有统计学意义(P<0. 05)。结论两性霉素B与人参茎叶皂苷在体外联用对几种念珠菌生物膜以协同作用为主。

Objective To explore the inhibitory activity of Ginseng stem-leaf saponins（GSLS） combined with amphotericin B（AMB） against Candida.spp biofilms in vitro.Methods Thirty one clinical isolates of Candida were identified to species level based on ITS and beta-tubulin gene sequencing. Drug sensitivity assays were performed on clinical and standard strains according to a modified version of CLSI M27-A3 reference method. The activity and total amount of biofilms were measured by colorimetric XTT-reduction assay and crystal violet spectrophotometry.Results There were 16 strains of Candida albicans , 6 Candida parapsilosis, 8 Candida tropicalis and 1 Meyerozyma guilliermondi i among 31 clinical isolates of Candida species. The FICI values of the combined inhibitory effects of AMB and GSLS on the test strains were all ≤0.5. The formation of the biofilms and viability of the strains were more markedly inhibited by AMB combined with GSLS comparing to AMB or GSLS used alone in vitro. The difference of biofilm production between single and combined treatment was statistically significant（ P 〈0.05）.Conclusion AMB combined with GSLS has synergistic effects on Candida biofilms.