Traditional Chinese Herbs Screening For Eliminating Drugs Resistance Of Beta-Lactam Type Of Escherichia Coli From Chickens

Traditional Chinese medicine(TCM)has many advantages,such as complex components,multi-target effect in eliminating bacterial resistance,abundant drug sources,low toxicity,low disability and no drug resistance.The research and development of TCM to eliminate bacterial resistance has become the focus of attention.This project studied the effect of water extracts of 11 kinds of traditional Chinese medicine on eliminating the resistance of chicken-derived E.coli to beta-lactam drugs,clarified the mechanism of eliminating the resistance of E.coli to beta-lactam antibiotics,and provided theoretical support for developing new green and natural feed-resistant additives for eliminating bacteria.1.In this study,11 kinds of traditional Chinese medicines were selected.Eight strains of chicken-derived E.coli with multi-drug resistance to beta-lactams were selected as test subjects.The minimum inhibitory concentration of water extracts of traditional Chinese medicines against E.coli was determined by double dilution method.After 3 days of continuous treatment with 1/2 MIC water extracts of traditional Chinese medicines,the MIC of 9 kinds of beta-lactams against E.coli were detected by microplate method.The results showed that the effect of 7 kinds of Chinese medicinal herbs on the elimination of E.coli resistance was obvious,followed by hawthorn,Scutellaria,Coptis,rhubarb,Herba euphorbiae humphora,dandelion and tongue grass.Hawthorn water extract had the elimination effect on the resistance of 9 kinds of antibiotics.2.The effect of Hawthorn water extract on the elimination rate of ?-lactam resistance of chicken E.coli.Eight strains of chicken E.coli with multiple drug resistance to ?-lactam were treated with Hawthorn water extract,and the elimination rate of drug resistance was determined by photoprinting method.The results showed that the elimination rate of other antibiotics was above 20% except cefepime(FEP),and the elimination rate of cefoxitin(FOX)resistance was 41.2%.3.To determine the elimination of E.coli plasmids and the activity of E.coli ESBLs before and after the water extract of hawthorn,and to elucidate the mechanism of eliminating the resistance of E.coli to beta-lactams.The results showed that the plasmid profiles of 8 E.coli strains changed after 3 days of treatment with hawthornwater extract,and the plasmid bands decreased by 1-3.Hawthorn water extract could not inhibit the activity of ESBLs.To sum up,7 kinds of traditional Chinese medicine which could eliminate the resistance of E.coli to ?-lactam drugs were selected from 11 kinds of traditional Chinese medicine,among which Hawthorn water extract had the best effect,which could eliminate the resistance of E.coli to 9 kinds of ?-lactam drugs.The elimination of drug resistance of E.coli by Hawthorn water extract is closely related to the elimination of plasmid,rather than by inhibiting the activity of extended-spectrum ?-lactamase in E.coli,which lays a foundation for the development of traditional Chinese medicine feed additives to eliminate drug resistance of E.coli.