【作者】 张丽；

【导师】 谷洁；

【作者基本信息】 西北农林科技大学 ， 环境科学， 2018， 硕士

【摘要】 随着中药产业发展而产生大量中药渣废弃物,其富含丰度营养物质和生物活性成分。目前中药渣资源化利用率低,不仅造成资源浪费而且污染环境。中药渣的合理处置是环境领域亟待解决的问题。抗生素因具有防治疾病和促进畜禽生长作用而在规模化养殖业中被广泛应用,大部分抗生素以其原体或代谢物形式随尿液和粪便排出,由于抗生素选择性压力可能产生抗生素抗性基因（antibiotic resistance genes,ARGs）。ARGs可通过水平基因转移（Horizontal gene transfer,HGT）和垂直转移使人类致病菌获得抗性,从而削弱抗生素药效,甚至可能产生超级细菌,威胁人类健康。好氧堆肥和厌氧发酵是固体废弃物资源化利用的常用技术手段,资源化利用后产物的农业利用是ARGs进入环境的重要途径。本文研究了中药渣和畜禽粪便共资源化利用过程和产物中ARGs的变化,分析了ARGs、基因遗传元件（MGEs）和微生物群落的关系,以期揭示中药渣和猪粪共资源化利用过程中ARGs变化的微生物学机理。取得的主要结果和结论如下:（1）中药渣能有效的降低除tetC之外的大多数目标ARGs（0.18 logs–2.82 logs）和MGEs（0.47 logs–3.34 logs）,而且对好氧堆肥产品中Turicibacter、Terrisporobacter、Clostridium_sensu_stricto₁、Lactobacillus和Romboutsia具有抑制作用。Network分析和RDA分析表明,微生物群落结构变化是引起中药渣好氧堆肥过程中ARGs丰度变化的主要机制;相关性分析表明,中药渣可通过降低基因遗传元件丰度抑制HGT从而削弱ARGs的传播。（2）中药渣厌氧发酵使猪粪中14种ARGs的丰度显著降低,其降幅为36.7%–96.5%。由环境因子引起的细菌群落演替是中药渣和猪粪共厌氧发酵过程中ARGs变化的主要驱动因素;中药渣不仅能减少ARGs的潜在宿主菌（其中包括部分人类致病菌）的多样性和相对丰度,而且能抑制HGT。ARGs潜在宿主菌主要属于Firmicutes和Proteobacteria。综上所述,中药渣和猪粪共好氧堆肥和厌氧发酵均能有效削减畜禽粪便中ARGs和MGEs,而且好氧堆肥削减效果优于厌氧发酵;微生物群落结构变化是引起中药渣和猪粪共资源化利用过程中ARGs丰度变化的主要机制;中药渣不仅能减少ARGs的潜在宿主菌而且能抑制HGT。因此,好氧堆肥和厌氧发酵是行之有效处理中药渣和畜禽粪便循环利用的生物方法。更多还原

【Abstract】 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.更多还原