摘要
目的：探讨白头翁汤正丁醇提取物butyl alcohol extract of Baitouweng decoction,BAEB对热带念珠菌（Candida tropicalis）毒力因子细胞表面疏水性、菌丝及生物膜形成的影响。方法：采用微量稀释法测定BAEB对热带念珠菌的最低抑菌浓度（MIC）;XTT还原法测定BAEB对热带念珠菌生物膜抑制作用（SMIC80）,Time-Kill法检测BAEB对热带念珠菌活菌数的动态影响;水-烃两相法测定BAEB对热带念珠菌细胞表面疏水性（cell surface hydrophobicity,CSH）的影响;荧光显微镜观察BAEB对热带念珠菌菌丝形态的影响;扫描电镜观察BAEB对热带念珠菌生物膜形态的影响;激光共聚焦显微镜检测BAEB对热带念珠菌生物膜荧光信号强度的影响;实时荧光定量PCR（q RT-PCR）检测菌丝及生物膜相关基因UME6,NRG1,ALST3的表达量变化。结果：BAEB对9株热带念珠菌的MIC在64-128 mg·L^-1,对热带念珠菌生物膜的SMIC80为256-512 mg·L^-1,FLZ对热带念珠菌的MIC在1-1 024 mg·L^-1,SMIC80为1 024 mg·L^-1或以上,Time-Kill曲线显示256,512 mg·L^-1BAEB具有明显的杀菌作用,CSH实验显示128,256,512 mg·L^-1BAEB均能够降低其表面疏水性,SEM观察到512 mg·L^-1BAEB能够有效抑制热带念珠菌在硅胶导尿管上生物膜完整度,CLSM显示256,512 mg·L^-1BAEB可以明显降低生物膜荧光信号强度,q RT-PCR检测显示在256,512 mg·L^-1BAEB作用下,ALST3,UME6基因表达量显著下调,NRG1无明显变化。结论：BAEB可以抑制热带念珠菌细胞表面疏水性、菌丝及生物膜形成等毒力因子。
Objective ： To investigate the effects of butyl alcohol extract of baitouweng decoction （BAEB） on the fungal cell surface hydrophobicity （CSH）, filamentation and biofilm formation of Candida tropicalis. Method： Gradual dilution method was used to determine the MIC. XTI＇ assay was applied to determine the SMIC80. Time-Kill assay was employed to draw the Time-Kill curve. The water- hydrocarbon two-phase assay was used to measure the cell surface hydrophobicity. Scanning electron microscopy （SEM） was applied to observe the morphological changes of the biofilm. Confocal laser scanning microscopy （CLSM） was applied to determine the thickness of the biofilm. The quantification real-time PCR （qRT-PCR） was used to detect expression changes of releated genes （ UME6, ALST3 and NRG1）. Result： The MICs of BAEB against C. tropicalis strains are determined as 64-128 mg ·L^-1. The SMICs0s of BAEB against the biofilm of Candida tropicalis strains are determined as 256-512 mg ·L^-1. Time-Kill curve results indicate that BAEB has a promise fungicidal effect at 256 and 512 mg ·L^-1. SEM results shows that 512 mg ·L^-1 BAEB can inhibit the formation of C. tropicalis biofilm on Sihcone catheter , and the morphology of biofilm is also affected by BAEB. The thickness of C. tropicalis biofilm is reduced by BAEB according to CLSM results. Furthermore, qRT-PCR results indicate that expression of UME6 and ALST3 are significantly down-regulated by BAEB 256,512 mg·L^-1 , and NRG1 is not affected by BAEB. Conclusion： BAEB inhibits effectively the CSH, filamentation and biofilm formation of VVC strains of C. tropicalis.
出处
《中国中药杂志》
CAS
CSCD
北大核心
2015年第12期2396-2402,共7页
China Journal of Chinese Materia Medica
基金
安徽省自然科学基金项目(1408085MH165)
安徽中医药大学校级科研项目(2014zr026)
