猪粪中抗生素厌氧消化降解阈值与降解机制研究

Antibiotics are extensively used on animals, and most of them are excreted unchanged in manure. Manure containing antibiotics is considered a hazardous substance that entails high health risk to the environment and human. Anaerobic digestion (AD) could not only treatment animal waste but also generate valuable biogas. However, the behavior of antibiotics contained in manure during AD process has not been clearly understood, such as, the threshold for complete antibiotic removal and the mechanism for antibiotic degradation during AD process. This study determine the swine manure and maximum antibiotic residues (sulfadimidine and sulfamethoxazole) as research object, through investigation of residual antibiotics in the livestock waste distribution. Firstly, using response surface method to determine the threshold for complete antibiotic removal by AD, and the influence of the antibiotic concentration on the performance of AD process. Secondly, using the environment isotope method to analyze the antibiotic degradation and fate in the acidification phase and methane producing phase. Finally, the microbial community structure in the acidification phase and methane producing phase were researched with molecular biological technique, and together with the antibiotics degradation during AD to investigate the mechanism of antibiotic degradation during AD process. This research has significance for providing scientific basis to establish effective control technology of residual antibiotics in swine manure, and promoting the recycle of swine manure.

由于畜禽养殖业中抗生素的使用，且畜禽对抗生素吸收率低，导致畜禽废弃物中残留大量抗生素，对生态环境带来了潜在的健康隐患。厌氧消化技术处理畜禽废弃物，既可以减少污染，又能够实现废弃物资源化。但畜禽废弃物中残留的抗生素在厌氧消化处理过程中存在降解阈值不明、降解机制不清等问题。本研究以猪粪和猪粪中残留较多的抗生素（磺胺二甲基嘧啶、磺胺甲恶唑）为研究对象；采用响应曲面法综合分析厌氧消化效果与抗生素降解之间的交互作用，确定抗生素可厌氧消化完全降解阈值；利用环境稳定同位素分析方法对抗生素在猪粪厌氧消化水解酸化、产甲烷阶段中的降解产物分析，探究抗生素厌氧消化降解途径；基于分子生物学技术分析水解酸化、产甲烷阶段中微生物群落演替规律，结合抗生素厌氧消化降解途径，揭示抗生素在以猪粪为基质的厌氧消化过程中的降解机制。为建立猪粪中残留抗生素的高效厌氧控制技术提供科学依据，对促进猪粪资源化利用具有重要意义。

由于畜禽养殖业中抗生素的使用，且畜禽对抗生素吸收率低，导致畜禽废弃物中残留大量抗生素，对生态环境带来了潜在的健康隐患。厌氧消化技术处理畜禽废弃物，既可以减少污染，又能够实现废弃物资源化。但畜禽废弃物中残留的抗生素在厌氧消化处理过程中存在降解阈值不明、降解机制不清等问题。本研究以猪粪和猪粪中残留较多的抗生素（磺胺二甲基嘧啶、磺胺甲恶唑）为研究对象；采用响应曲面法综合分析厌氧消化效果与抗生素降解之间的交互作用，确定了抗生素可厌氧消化完全降解阈值；利用抗生素在猪粪厌氧消化水解酸化、产甲烷阶段中的降解产物分析，探究抗生素厌氧消化降解途径；基于分子生物学技术分析水解酸化、产甲烷阶段中微生物群落演替规律，结合抗生素厌氧消化降解途径，揭示抗生素在以猪粪为基质的厌氧消化过程中的降解机制。本研究为建立猪粪中残留抗生素的高效厌氧控制技术提供科学依据，对促进猪粪资源化利用具有重要意义。