| Since the advent of antibiotics,the prevalence of clinical infections in patients has been greatly reduced.Although the widespread use of antibiotics has brought good news to human health,it has also produced many negative effects.For example,the problem of bacterial resistance has become more and more serious,and it has reached an uncontrollable level.The development and development of new antibiotics are slow,new species.Resistant bacteria can be resisted and so on.Symbiotic bacteria(Escherichia coli,Klebsiella pneumoniae)transmit drug resistance genes to other pathogens in the human body and the environment,causing the spread of drug resistance and becoming a repository of drug resistance genes.The study found that the drug-resistant bacteria isolated in terminal foods have the greatest correlation with drug-resistant bacteria that infect humans.This experiment hopes to obtain ESBLs,carbapenem-resistant and polymyxa-resistant bacteria in retail food and patient feces by separation.A class of drug-resistant bacteria,understand the pollution of ESBLs,carbapenem-resistant and polymyxin-resistant bacteria in some parts of our province.Therefore,the target drug-resistant strains selected for this study are Escherichia coli and Klebsiella pneumoniae.The study will collect screening strains from several retail foods and patients' feces,and then separate them by PCR,gene sequencing and other technologies.Statistical analysis of drug resistance gene carrying of strains.Due to the excessive use of antibiotics,the emergence of super bacteria poses a major threat to humans,and the search for new antibiotic alternatives is imminent.Researchers at home and abroad attach great importance to the search for safe and effective bio-bacteria technology in the food field.Lactobacillus is considered to be a food-grade safe microorganism worldwide,and some strains are listed as probiotics by FAO and WHO.Not only can we add lactic acid bacteria directly to foods in the form of food additives to improve human health,but we can also use its fermentation metabolites,especially lactic acid bacteria bacteriocin,as food preservatives and antibiotic substitutes to inhibit the growth of a large number of pathogenic bacteria.In recent years,it has been widely used as a biobacterial agent because of its advantages of being non-toxic,safe,and efficient.At present,there are only a few kinds of metabolites widely used,and bacteriocins are widely used.Due to the nature of bacteriocin itself,not all bacteriocins produced by metabolism can be used in any environment.Only by continuously excavating new high-efficiency bacteriocin products can we continue to promote the development of bio-bacteriostatic technology.Therefore,this experiment should use several metabolites of lactic acid bacteria known in the laboratory to investigate the simple inhibition of the selected drug-resistant strains,and provide reference for the search for efficient and stable biological antibacterial agents.The results of resistant strains and drug resistance genes were as follows:(1)A total of 120 samples of retail food and patient stools(60 food and feces)were collected from some fresh supermarkets and hospitals in Harbin,and 388 strains of resistant strains were screened by three antibiotics with different antibacterial spectrum.(2)Positive rate of samples: the detection rate of food was 73.33%,the detection rate of feces was 65.00%,and the detection rate was basically the same;the distribution of drug-resistant strains: 218 strains of resistant large intestine were more than 170 strains of resistant lungs,from drug resistance Types: 276 strains of ESBLs,68 strains of KPC,and 44 strains of PO.Overall,ESBLs accounted for the largest proportion and environmental pollution was relatively serious.(3)The distribution of drug resistance genes obtained by molecular biology techniques is as follows: CTX-M-7/8(frequency 159,57.61%)and CTX-M-11/12(frequency 135,ratio)were detected in ESBLs strains.48.91%);bla IMP was detected in KPC strain(frequency 6,accounting for 8.82%),bla NDM(frequency 7,accounting for 10.29%);MCR-1 was detected in PO strain(frequency 4,9.09%).It can be seen that the drug-bearing gene carrying rate of ESBLs strain is higher,and only one drug-resistant genotype is detected in the PO strain,and there is no distribution and dispersion,which tends to concentrate on the epidemic trend.Through the above test results,the spread of drug resistance genes in some areas of our province was obtained,which provided a reference for the prevention and traceability of the spread and prevalence of ESBLs,KPC and PO resistance genes,and provided guidance for the use of antibiotics in clinical drugs and the environment.To warn against the abuse of antibiotics in our province.Bacteriostatic experiment: The inhibition effect of the four lactic acid bacteria selected in this study on drug-resistant strains did not appear. |
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