Antibacterial Mechanisms of Berberine and Reasons for Little Resistance of Bacteria  

作　　者：JIN Jian-ling,HUA Guo-qiang,MENG Zhen,GAO Pei-ji State Key Laboratory of Microbial Technology,School of Life Sciences,Shandong University,Jinan 250100,China 

出　　处：《Chinese Herbal Medicines》2011年第1期27-35,共9页中草药（英文版）

基　　金：The National Natural Sciences of Chinese(81041089)

摘　　要：Objective To study the antibacterial mechanisms of berberine and try to understand the reasons why bacteria cells difficultly resisted to it.Methods Detecting the minimal inhibitory concentration(MIC) of bacterial cultures incubated under sub-MIC concentration of berberine,Huanglian,and Neomycin for more than 200 generations,in order to analyze the bacteria resistance.Detecting the binding kinetics of berberine to DNA,RNA,and proteins.Observing the changes in bacterial cell surface structure with scanning electron microscopy.Detecting the Ca2 +and K +released from berberine-treated bacterial cells with atomic absorption spectrum.Detection the absorption of methyl-3H-thymine ( 3 H-dT),3 H-uridine( 3 H-U),and 3 H-tyrosine( 3 H-Tyr)into berberine-treated bacterial cells.Results MICs of bacterial cultures,growing more than 200 generations in MH medium with 1/2 MIC of berberine(BA200) or Huanglian(HA200),did not increase compared to the control,while remarkably increased in MH medium with 1/2 MIC of Neomycin (NA200).In addition,from the culture NA200 it was easy to isolate resistant mutant strains which could grow in MH medium with more than four times MIC Neomycin,but from the culture BA200 and HA200 it was difficult to isolate berberine or Huanglian mutant strains could grow in MH medium with more than four times MIC berberine or Huanglian.The binding kinetics of berberine to DNA,RNA,and proteins illustrated that berberine could easily and tightly bind to DNA and RNA,and hardly dis-bind from DNA-and RNA-berberine complexes.Berberine could easily bind to protein too,but also easily dis-bind from berberine-protein complex.The bacterial cells treated with berberine sharply decreased the absorption of 3 H-dT,3 H-U,and 3 H-Tyr,as the radioactive precursors of DNA,RNA,and protein biosynthesis.Berberine could damage bacterial cell surface structure,especially for Gram-negative bacteria.Ca2 +and K + released from berberine-treated cells increased significantly compared to the control.Conclusion All of above results indicateObjective To study the antibacterial mechanisms of berberine and try to understand the reasons why bacteria cells difficultly resisted to it.Methods Detecting the minimal inhibitory concentration(MIC) of bacterial cultures incubated under sub-MIC concentration of berberine,Huanglian,and Neomycin for more than 200 generations,in order to analyze the bacteria resistance.Detecting the binding kinetics of berberine to DNA,RNA,and proteins.Observing the changes in bacterial cell surface structure with scanning electron microscopy.Detecting the Ca2 +and K +released from berberine-treated bacterial cells with atomic absorption spectrum.Detection the absorption of methyl-3H-thymine ( 3 H-dT),3 H-uridine( 3 H-U),and 3 H-tyrosine( 3 H-Tyr)into berberine-treated bacterial cells.Results MICs of bacterial cultures,growing more than 200 generations in MH medium with 1/2 MIC of berberine(BA200) or Huanglian(HA200),did not increase compared to the control,while remarkably increased in MH medium with 1/2 MIC of Neomycin (NA200).In addition,from the culture NA200 it was easy to isolate resistant mutant strains which could grow in MH medium with more than four times MIC Neomycin,but from the culture BA200 and HA200 it was difficult to isolate berberine or Huanglian mutant strains could grow in MH medium with more than four times MIC berberine or Huanglian.The binding kinetics of berberine to DNA,RNA,and proteins illustrated that berberine could easily and tightly bind to DNA and RNA,and hardly dis-bind from DNA-and RNA-berberine complexes.Berberine could easily bind to protein too,but also easily dis-bind from berberine-protein complex.The bacterial cells treated with berberine sharply decreased the absorption of 3 H-dT,3 H-U,and 3 H-Tyr,as the radioactive precursors of DNA,RNA,and protein biosynthesis.Berberine could damage bacterial cell surface structure,especially for Gram-negative bacteria.Ca2 +and K + released from berberine-treated cells increased significantly compared to the control.Conclusion All of above results indicate

关 键 词：antibacterial effect antibiotic resistance BERBERINE binding kinetics NEOMYCIN 

分 类 号：R285[医药卫生—中药学]