摘要
目的探究表没食子儿茶素没食子酸酯(EGCG)对鲍曼不动杆菌ABK450生物被膜形成的作用。方法建立ABK450成熟生物被膜模型,加入蛋白酶K、脱氧核糖核酸酶I(DNaseI)、高碘酸钠处理成熟生物被膜,并测定其生物被膜的残留量。微量肉汤稀释法测定EGCG对ABK450的最低抑菌质量浓度(MIC)。不同质量浓度EGCG处理ABK450后,采用结晶紫染色法测定其生物被膜的形成量,MTT法检测生物被膜细胞相对活性,显微镜成像技术观察生物被膜结构;分别运用Bradford法、苯酚-硫酸法和微量分光光度法测定其生物被膜胞外蛋白、胞外多糖和胞外DNA(eDNA)含量。结果ABK450静置培养48 h可形成成熟生物被膜,其生物被膜胞外聚合物中含有大量多糖和蛋白质以及少量eDNA。EGCG对ABK450的MIC为512 mg/L。与0 mg/L比较,32 mg/L EGCG开始抑制ABK450生物被膜的形成,64 mg/L EGCG开始抑制生物被膜细胞活力,同时对生物被膜结构破坏效果显著,使形成的生物被膜结构更为松散,并且抑制效果随着EGCG质量浓度的增加而增强。与0 mg/L比较,32 mg/L EGCG明显抑制了生物被膜蛋白质和多糖的合成,但对eDNA的分泌并无影响。结论EGCG可以有效抑制ABK450生物被膜的形成。
Aim To explore the effect of epigallocatechin gallate(EGCG)on the biofilm formation of Acinetobacter baumannii 450.Methods A mature biofilm model of ABK450 was established,add protease K,deoxyribonuclease I(DNaseI),and sodium periodate were used to treat mature biofilm,followed by the determination of the residual amount of biofilm.The minimum inhibitory concentration(MIC)of EGCG against ABK450 was determined using the micro broth dilution method.After treating ABK450 with EGCG of different concentrations,the formation of biofilm was determined by crystal violet staining,and the relative activity of biofilm cells was detected by MTT assay;The structure of biofilms was observed by using microscopy imaging technology;The content of extracellular proteins,extracellular polysaccharides,and extracellular DNA(eDNA)in its biofilm were measured by using Bradford method,phenol sulfuric acid method,and micro spectrophotometry,respectively.Results ABK450 can form a mature biofilm after 48 hours of static cultivation,and the extracellular polymeric substances of the biofilm contained a large amount of polysaccharides and proteins,as well as a small amount of eDNA.The MIC of EGCG for ABK450 was 512 mg/L.Compared with 0 mg/L,32 mg/L EGCG began to inhibit biofilm formation,64 mg/L EGCG began to inhibit biofilm cell viability,and EGCG had a significant destructive effect on biofilm structure,making the formed biofilm structure disrupted,and the inhibitory effect increased with the increase of EGCG mass concentration.Compared with 0 mg/L,32 mg/L EGCG significantly inhibited the synthesis of proteins and polysaccharides in biofilm bacteria,but had no effect on the secretion of eDNA.Conclusion EGCG has a significant inhibitory effect on the biofilm formation of ABK450.
作者
罗宇辰
李昀霏
罗湘
王欣
柏琴琴
陈曦
颜淑妩
梁好
周罗星
陈丽丽
LUO Yuchen;LI Yunfei;LUO Xiang;WANG Xin;BAI Qinqin;CHEN Xi;YAN Shuwu;LIANG Hao;ZHOU Luoxing;CHEN Lili(School of Public Health,Hengyang Medical School,University of South China,Hengyang 421001,Hunan,China;Changsha Qianhai Biotechnology Co.,Ltd.,Changsha 410000,Hunan,China;Henyang Center for Disease Control and Prevention,Hengyang 421001,Hunan,China)
出处
《中南医学科学杂志》
2025年第4期565-569,共5页
Medical Science Journal of Central South China
基金
国家自然科学基金青年科学基金项目(81903369)
湖南省大学生创新创业训练计划(D202405231928162926)。
