Study On Elimination Effect Of Chinese Medicines On Drug Resistance Of Escherichia Coli Isolated From Swine

With extensive and irregular use of antibiotics in animal husbandry,the increasing of bacterial resistance increasing and prevalence of multiple drug resistance not only causes enormous losses to the livestock and increase the difficulty to control bacterial diseases in humans and animals,but also could threaten to people's life.Many data shows more severe situation of drug resistance of Escherichia coli in China,genes and the genetic mechanisms of drug resistance,but traditional Chinese medicine on Elimination of the lack of detailed and profound description of the resistance.The stains of Escherichia coli in this research was isolated from swines with disease and9 strains Escherichia coli which had strong drug resistance was selected by drug sensitivity testing,then applying agarose gel electrophoresis to get the plasmid profile of 9 strains Escherichia coli,setting?DNA/Hind III as a marker to established standard curve which could calculation out the size of plasmid profile of 9 strains Escherichia coli;using PCR to detect drug resistance gene GyrA,ParC,TetA and TetB.Results:9 strains of Escherichia coli had different sensitive on 18 antibiotics,the number resistance drug are in 7 above,and the highest was 13,which 7 strains Escherichia coli were resisted to 10 or 10 above of antibiotic,3 strains Escherichia coli ere resisted to 13 antibiotics;all strains on 12 species antibiotics of resistance drug rate are larger than 50%,The resistance drug rate on Ampicillin,Penicillin,Amoxicillin,and Erythromycin resistance drug rate reached 100%,Which on Tetracycline,and Doxycycline reached 88.9%;Polymyxin b,Spectinomycin,Streptomycin,Neomycin,Enrofloxacin and Ciprofloxacin are effective;9 strains Escherichia coli quality had various plasmid profiles,and the size of stripe is about 0.574x10~3 bp-19.065x10~3bp,all plasmid profiles had a stripe about for 19.065 Kbp,Which suggested that these Escherichia coli may be in the same popular.9 strains of Escherichia coli detected a total of four drug-resistant genes included GyrA,ParC,TetA and TetB.Study on the elimination effect of 7 Chinese medicines on drug resistance of 9 strains of Escherichia coli,set the SDS group and the blank group,Three group's rates of drug resistance were recorded at 24 h,48 h and 72 h of the three time points,eliminate testing of each group at each time point were repeated three times.After elimination test in 72 h,Conducting the drug-sensitive test,gel electrophoresis plasmid,PCR the Elimination of drug resistance genes for the Elimination of traditional Chinese medicine respectively.All results shows that:(1)the rate range of 7 traditional Chinese medicine eliminate group at three time points is 0.9%-57.9%,(2)After elimination test,Escherichia coli recovered sensitivity of 1-4 antibiotics,The drug resistance of Radix gourp had not changed;The amount of antibiotics which recovered sensitivity after elimination tests was related to inhibitory effect of traditional Chinese medicine on Escherichia coli.(3)the plasmid of 6 traditional Chinese medicine resistance plasmid have eliminated 1-5 strips;The eliminates which lost 574 bp plasmid band recovered sensitivity to some fluoroquinolone antiboiotics,which proves 574 bp plasmid band was related to resistance to quinolone antibiotics(4)The eliminates of seven traditional Chinese medicines,all of which detected out the genes of GyrA,ParC and TetA,all of which failed to detect the tetracycline resistance gene.It showed that the tetra-resistant gene TetB was eliminated,and the traditional Chinese medicine had the effect of eliminating the drug resistance gene TetB in Escherichia coli.