Inhibition Of Klebsiella Pneumoniae Biofilm By Chlorogenic Acid Combined With Levofloxacin In Vitro

Research background and Object Klebsiella pneumoniae is a common pathogen causing nosocomial infection,which can cause respiratory tract,digestive tract and urinary tract infection.According to the 2013 CHINET surveillance of bacterial resistance reported in Enterobacteriaceae Klebsiella compared with the previous year increased,and in carbapenem resistant strains of Klebsiella pneumoniae was the most,to imipenem and meropenem resistance rates were greater than 10.0%.KPN easy to produce biological membrane,the bacteria layer by layer,with the in-depth study of biological membranes,KPN found that the resistance to antibiotics and the formation of biofilm in vivo closely related.The domestic and foreign research shows that the combined use of quinolones and macrolides can effectively inhibit the synthesis of bacterial polysaccharide protein complex,thus inhibiting the formation of biofilm.However,the mature biofilm becomes more resistant to the combined use of these two kinds of antibiotics.Chlorogenic acid is the active ingredients of Chinese medicine,Chinese herbal medicine extracted from honeysuckle.Data shows that chlorogenic acid can inhibit the biofilm formation of Pseudomonas aeruginosa,but the inhibitory effect of chlorogenic acid is rarely reported on how similarly prone to biofilm KPN.This study intends to a guangzhou hospital of Klebsiella pneumoniae clinical distribution and drug resistance analysis,simultaneous detection of ESBLs genotype BF formation of Klebsiella pneumoniae,and through in vitro experiment,effects of chlorogenic acid on KPN biofilm and chlorogenic acid in combination with LEV on KPN.To provide the basis for antimicrobial treatment clinical strategies to develop scientific and rational.Methods The clinical isolates of 62 strains of Klebsiella pneumoniae were collected from a hospital.The identification and drug sensitivity analysis were carried out,and the biofilm positive screening was carried out.The biofilm positive strains were identified by ESBLs genotyping,biofilm model and drug interference wereconstructed.Results A total of 62 strains of Klebsiella pneumoniae by semi quantitative crystal violet staining,33 strains of bacteria producing biofilm positive,accounted for53.2%(33/62).ESBLs detection of 24 strains of BF Klebsiella pneumoniae,gene amplification by PCR,results showed that all strains were amplified SHV gene54.17%(13/24),TEM41.67%(10/24),a gene 4 strains exist at the same time SHV and TEM gene,did not detect the CTX-M gene.In vitro modeling and drug interference,single drug group were black floc(representing dense biofilm)accounted for less than 25%,the combination group were less than 15%,while the untreated group black floc accounted for about 60%.Conclusion 1.The ESBLs genotype of BF Klebsiella pneumoniae was mainly TEM and SHV.2.Chlorogenic acid could inhibit the biofilm of Klebsiella pneumoniae,and the effect was more significant when chlorogenic acid combined with levofloxacin.