大黄酸抗耐甲氧西林金黄色葡萄球菌的抗菌机制  

Antibacterial mechanism of rhein against methicillin-resistant Staphylococcus aureus

作　　者：覃静 祖敬芝 罗沙 彭静 任瑶瑶[1] 谭睿[1] QIN Jing;ZU Jingzhi;LUO Sha;PENG Jing;REN Yaoyao;TAN Rui(School of Life Science and Engineering,Southwest Jiaotong University,Chengdu,Sichuan 610000,China;School of Medicine,Southwest Jiaotong University,Chengdu,Sichuan 610000,Chin)

机构地区：[1]西南交通大学生命科学与工程学院,四川成都610000 [2]西南交通大学医学院,四川成都610000

出　　处：《微生物学通报》2021年第6期2111-2117,共7页Microbiology China

基　　金：国家重点研发计划(2018YFC1706200);四川省重点研发项目(20ZDYF3291);四川省中医药管理局重点项目(2018C031);中央高校基本科研业务费专项基金(A0920502052001-8)。

摘　　要：【背景】耐甲氧西林金黄色葡萄球菌(Methicillin-Resistant Staphylococcus aureus,MRSA)是医院及社区常见的机会性致病菌,具有多重耐药性、高发病率和高死亡率的特点。MRSA感染已成为全球医学界的普遍难题之一。【目的】研究大黄酸对MRSA的抗菌机制。【方法】以二倍稀释法测定大黄酸对MRSA的最小抑菌浓度(Minimum Inhibitory Concentration,MIC);通过MIC测定大黄酸对MRSA动态抑菌作用;建立生物膜模型,测定大黄酸在生物膜屏障下对生物膜内存活菌的影响,并通过扫描电镜观察不同浓度大黄酸作用后的MRSA菌体形态变化;用免疫荧光染色法、荧光分析法测定大黄酸对MRSA细胞质膜去极化和细胞膜通透性的影响。【结果】大黄酸对MRSA的MIC为8μg/mL;大黄酸能对生物膜内存活菌有明显的抑制作用,而且在大黄酸作用下菌体的形态发生明显皱缩和破损,破损严重程度与浓度呈正相关;随着大黄酸浓度和作用时间的增加,荧光强度出现明显变化,细胞膜的通透性发生改变。【结论】大黄酸主要通过损伤细菌的细胞膜,从而抑制细菌的生长和繁殖。[Background] Methicillin-resistant Staphylococcus aureus(MRSA) is a common opportunistic pathogen in hospitals and the community, characterized by multi-drug resistance, high morbidity and mortality, and MRSA infection has become one of the common problems in the global medical community. [Objective] To study the antibacterial mechanism of rhubarb acid against MRSA. [Methods] To determine the minimum inhibitory concentration(MIC) of rhubarb acid on MRSA by two-fold dilution method;to determine the dynamic inhibitory effect of rhubarb acid on MRSA by MIC;to establish a biofilm model and determine the effect of rhubarb acid on viable bacteria in biofilm barrier, and to observe the effect of rhubarb acid by scanning electron microscope. The morphological changes of MRSA bacteria after the action of different concentrations of rhubarb acid;the effects of rhubarb acid on the depolarization and permeability of MRSA cell plasma membrane were determined by immunofluorescence staining and fluorescence analysis. [Results] The MIC of rhein on MRSA was 8 μg/mL;rhein had obvious inhibitory effect on the surviving bacteria in the biofilm, and under the effect of rhein, the morphology of the bacterial body was obviously wrinkled and damaged, and the severity of damage was positively correlated with the concentration;with the increase of rhein concentration and effect time, the fluorescence intensity changed obviously, and the permeability of the cell membrane changed. [Conclusion] Rhein mainly damaged the cell membrane of bacteria, thus inhibiting the growth and reproduction of bacteria.

关 键 词：大黄酸 耐甲氧西林金黄色葡萄球菌 抗菌机制 

分 类 号：R285[医药卫生—中药学]