The Inhibitory Characteristic Of Chinese Herb Medicines And The Bacterial Resistant Characteristic To Them

IntroductionThe application of antibiotics contributes greatly to the health,survival and development of human beings.While,as the development of universal and unreasonable use of antibiotics,antibiotic resistance has become a serious problem, and draws attention throughout the world.Great efforts have been taken aiming to solve this problem,but it still get worse.The antibiotic resistance of bacterial can not avoid due to the fact that antibiotic is un-replaceable in therapy and people get more and more dependent of antibiotics. Because it's an instinct characterisitic for bacteria to develop antibiotic resistance under the pressure of drugs,it's inevitable for bacteria to get resistant to the antibiotic when they touched.Chinese herb medicines or Chinese herb medicines + antibiotics may be possible solutions.Chinese herb medicine can resist,delay and eliminate antibiotic resistance.No drug-resistance bacterium was found during the using of Chinese medicine.The majority of Chinese medicine has a broad bacteriostatic spectrum.It can recover the micro-ecological balance,alleviate the select pressure,immunomodulate,enhance infection treatment,disturb the forming and diffuse of antibiotic resistance,and reverse antibiotic resistance.Some Chinese medicine is antitoxic in vivo.These advantages make Chinese medicine competitive in solving antibiotic resistance.Chinese medicine is attractive,but the research on Chinese medicine remains at a low level.Interrelated researches mostly focus on bacteriostatic spectrum and characteristic,elimination of antibiotic resistance,and extraction the effective components,these research works could not give us enough information about the bacteria resistance to herbal medicines.In this thesis,we have made primary research in characterization of microbial kinetics under the pressure of Chinese herb medicines, the efforts of Chinese medicine to microbial community(in vivo and in vitro),and molecular-ecology.Results The main results included:1.Research on the antibiotic resistance characteristic of pure culture under the pressure of drugWe use Salmonella Typhimurium TA100 as a Type Strain to study the bacterial antibiotic resistance characteristic under the pressure of drug(antibiotics and Chinese herb medicine) within 72 hours.The study suggests that physiology activities(MTT) and cfu(Colony-Forming Units) of TA 100 start to drop in logarithmic phase under the pressure of antibiotics (Cefotaxime Sodium,Gentamycin Sulfate,Azithromycin,Levofloxacin Hydrochloride Injection) of different concentration(2MIC,MIC,1/2MIC).The higher concentration the antibiotic has faster physiology activities and cfu drop.Cefotaxime Sodium has the fastest efforts of the inhibition on bacteria,which we can see from the rapid drop of the cfu rightly after the accession of Cefotaxime Sodium.The change of physiology activities is more sensitive than that of cfu.The change of physiology activities needs less time and it can change to a great extent.The resistant mutants emerge both in bacth culture and serial subculture under the pressure of antibiotics of different concentration(2MIC,MIC,1/2MIC).Lower concentration of antibiotics leads to higher resistant mutation.No drug-resistant mutant emerge both in bacth culture and serial subculture under the pressure of Chinese medicine(Rhizoma Coptidis,Radix Scutellariae,Sanhuang, Compound Lonicera Granules) of different concentration(2MIC,MIC,1/2MIC). Under the pressure of Chinese medicine(1/2MIC),hysiology activities and cfu drop at a lower speed than under the pressure of antibiotic in both culture system,and it's different from that drug-resistant mutants emerge in a large number under the pressure of antibiotic(1/2MIC).2.Research on the antibiotic resistance characteristic of artificial microbial community under the pressure of drug microbial community.Four bacterium(Klebsiella pneumoniae,Staphyloccocus aureus,Citrobacter freundii,Citrobacter freundii) are chosen to buildup the artificial community mode for the research of bacterial antibiotic resistance characteristic under the pressure of drug (antibiotics and Chinese herb medicine) within 72 hours.The study suggests that t in the artificial community mode is to get drug-resistant under the pressure of antibiotics(Cefotaxime Sodium,Gentamycin Sulfate, Azithromycin,Levofloxacin Hydrochloride Injection) of different concentration(2MIC,MIC,1/2MIC) in both culture system.Other strains may also become drug-resistant during the culturing.The lower concentration antibiotic has, the higher mutation rate predominant growing bacteria will have.The effects of inhibition and killing in the artificial community mode are better under the pressure of antibiotics of high concentration(＞2MIC) in serial subculture.More antibiotic resistant mutants emerge under the pressure of antibiotics of low concentration(MIC and 1/2MIC) in serial subculture than in the batch culture.No drug-resistant mutant of any strain in the artificial community mode emerge both in bacth culture and serial subculture under the pressure of Chinese medicine(Rhizoma Coptidis,Radix Scutellariae,Sanhuang,Compound Lonicera Granules) of different concentration(2MIC,MIC,1/2MIC).The cfu of predominant growing bacteria in the artificial community mode becomes fewer under the pressure of antibiotics of low concentration in both culture system,and it's different from that drug-resistant mutants of the predominant growing bacteria in the mixed culture emerge in a large number under the pressure of antibiotic(1/2MIC).Klebsiella pneumoniae,Staphyloccocus aureus,Citrobacter freundii and Citrobacter freundii can be distinguished by DGGE,which gives a fast molecular monitoring method.3.Mice experimentWe used the diarrhea mouse induced by Escherichia coli O157:H7 to study the therapy effects of Sanhuang.The result shows that the intestinal inflammation ratio of the diarrhea BALB/c mousse in San-Huang-Tang treatment group was significantly decreased but the kidney inflammation ratio only slightly decreased.Both intestinal inflammation ratio and kidney inflammation ratio of the San-Huang-Tang combination with streptomycine treatment group were significantly decreased.The change of constitution and proportion in the mice dejecta are detected by DGGE.And the identification of the strains contained in dejecta is under experiment.Conclusion:The application of antibiotics is sure to make bacteria become drug-resistant,while, there are no drug-resistant mutants emerging under the pressure of Chinese medicine of any concentration.This result gives a suggestion for solving the problem of antibiotic resistance.By the way of a artificial community model we can get rid of complex problems when studying with a natural bacterial community.And the artificial community model also solves the problem that it's hard to use a pure culture model to reveal the real process in vivo.Molecular ecological method was induced to the study on growing characteristic of a community under the pressure of drugs.DGGE was used to study the growing trait of the community in vivo and in vitro,and this technique can be used in similar research.