Abstract：
Tetracycline is an antibiotic with extensive veterinary use in the livestock industry. However, their widespread application poses risks to soil health as residue in livestock feces, and their removal is crucial for sustainable soil-ecosystem development. Physical and chemical approaches to extract tetracycline may have adverse effects on soil ecosystems, but no studies have thus far examined the potential for biological methods, such as collective degradation action of soil fauna. Thus, this study aimed to investigate the synergistic effects of lactic acid bacteria (LAB) and earthworms (Eisenia fetida) on biodegradation of tetracycline residues in sheep manure. We assessed earthworm biomass, tetracycline residue, and bacterial communities in both earthworm intestines and vermicompost. Earthworm biomass and tetracycline degradation efficiency increased significantly with LAB addition, with a degradation rate of up to 80.16%. This increase may be attributable to LAB acting as electron donors to spur tetracycline degradation. Additionally, we noted that tetracycline presence significantly influenced bacterial communities in earthworm intestines and vermicompost, elevating the abundance of potential pathogenic bacteria (e.g., Flavobacterium, Gammaproteobacteria, and Enterobacteriaceae). This finding suggests that heightened environmental stress from antibiotics could actually facilitate the growth of less prevalent bacteria, including potential pathogens. In conclusion, our study provides evidence supporting the effectiveness of LAB and earthworms in degrading tetracycline residues. In particular, LAB appears to mitigate stress from tetracycline exposure in earthworms, thus increasing their vermicomposting efficacy. Our work has important implications for soil management, with the potential to enhance pollution clean-up rates while minimizing negative side-effects to soil microbial communities.
摘要：
四环素是在畜牧业中具有广泛兽医用途的抗生素。然而,它们的广泛应用对土壤健康构成了风险，因为它们残留在牲畜粪便中，它们的去除对于可持续的土壤生态系统发展至关重要。物理和化学方法提取四环素可能会对土壤生态系统产生不利影响，但是到目前为止，还没有研究研究生物方法的潜力，如土壤动物的集体退化作用。因此，本研究旨在研究乳酸菌（LAB）和蚯蚓（Eiseniafetida）对羊粪中四环素残留的协同降解作用。我们评估了蚯蚓的生物量，四环素残留,以及蚯蚓肠道和蚯蚓粪中的细菌群落。蚯蚓生物量和四环素降解效率随着LAB的添加而显著提高,降解率高达80.16%。这种增加可能归因于LAB充当电子供体以刺激四环素降解。此外,我们注意到四环素的存在显著影响了蚯蚓肠道和蚯蚓粪中的细菌群落，提高潜在致病菌的丰度(例如，黄杆菌,γ变形杆菌,和肠杆菌科）。这一发现表明，抗生素引起的环境压力增加实际上可以促进不那么普遍的细菌的生长，包括潜在的病原体。总之,我们的研究提供了证据支持LAB和蚯蚓降解四环素残留的有效性。特别是,LAB似乎可以减轻四环素暴露在蚯蚓中的压力，从而增加了他们的蠕虫堆肥功效。我们的工作对土壤管理具有重要意义，有可能提高污染清理率，同时最大限度地减少对土壤微生物群落的负面影响。
