Mechanism Of Antibiotic Resistance Genes In The Process Of Co-resource Utilization Of Chinese Medicinal Herbal Residues And Swine Manure

With the development of the Chinese herbal medicine industry,a large amount of Chinese medicinal herbal residues is rich in abundance nutrients and biological active ingredients.However,the utilization of traditional Chinese medicinal herbal residues is low,which not only causes waste of resources but also pollutes the environment.It is currently including environmental science,the research topics urgently needed to be solved in the fields of chemistry and medicine.Antibiotics are widely used in large-scale aquaculture because of their role in disease prevention and promotion of livestock and poultry.Most antibiotics in the aquaculture process are excreted in urine and feces in the form of their original or metabolites due to the selective pressure of antibiotics.Antibiotic resistance genes?ARGs?may be produced.ARGs can obtain resistance to human pathogens through horizontal gene transfer?HGT?and vertical transfer,thereby impairing the efficacy of antibiotics,and may even produce super bacteria that threaten human health.Aerobic composting and anaerobic digestion are common technical means for the utilization of solid waste resources.The agricultural utilization of the products after resource utilization is an important way for ARGs to enter the environment.In this study,the effects of aerobic composting and anaerobic digestion on the co-resource utilization processes of Chinese medicinal herbal residues and livestock manure and ARGs in the product were studied using laboratory simulation methods,and the relationships between ARGs,genetic genetic elements?MGEs?and microbial communities were analyzed.The aim is to reveal the microbiological mechanisms that affect the change of ARGs through different resource utilization pathways.The main results and conclusions obtained are as follows:?1?Chinese medicinal herbal residues can effectively reduce most of the target ARGs?0.18 logs–2.82 logs?and MGEs?0.47 logs–3.34 logs?except for tetC,and aerobic composting is better than anaerobic digestion,and have inhibitory effects on Turicibacter,Terrisporobacter,Clostridium_sensu_stricto₁,Lactobacillus and Romboutsia in composting products.Network analysis and RDA analysis showed that the change of microbial community structure was the main mechanism for the abundance change of ARGs during aerobic composting of Chinese medicinal herbal residues;Correlation analysis showed that Chinese medicinal herbal residues could reduce the spread of ARGs by reducing the abundance of MGEs and inhibiting HGT.?2?The anaerobic digestion of Chinese medicinal herbal residues significantly reduced the abundance of 82.35% target ARGs in the swine manure?P < 0.05?,which was reduced by 36.7%-96.5%.The succession of bacterial communities caused by environmental factors is the main driving factor in the changes of ARGs during anaerobic digestion of Chinese herbal residue;Chinese medicinal herbal residues not only reduces the diversity and relative abundance of potential host bacteria?including some human pathogens?of ARGs,but also inhibits HGT.The potential host bacteria of ARGs mainly belong to Firmicutes and Proteobacteria.In conclusion,Chinese medicinal herbal residues composting and anaerobic digestion can effectively reduce ARGs and MGEs in livestock and poultry manure;changes in microbial community structure are the main mechanisms that cause changes in abundance of ARGs in the process of resource utilization of traditional Chinese medicinal herbal residues;It can reduce potential host strains of ARGs and can inhibit HGT.Therefore,the utilization of traditional Chinese medicine bacteria is a biological method that effectively handles the recycling of Chinese medicinal herbal residues and animal manure.