College of Forest and Biotechnology, Zhejiang Agricultural and Forestry University, Lin'an 311300, China; The Institute of Environment, Resources, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
The Institute of Environment, Resources, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
Sci Total Environ. 2019 Feb 1;649:396-404. doi: 10.1016/j.scitotenv.2018.08.212. Epub 2018 Aug 17.
Sawdust, rice husk, and mushroom residues are commonly used as bulking agents during manure composting; this work evaluated their potentiality for enhancing the removal of antibiotics and antibiotic resistance genes (ARGs) under a temperature-consistent condition. Results indicated that the addition of all the compost-bulking agents increased antibiotic removal in swine manure with increasing rates of 14.9%-33.4%; however they showed less effect on the reduction of residual antibiotics in chicken manure where fluoroquinolone (FQs) antibiotics are the dominant antibiotics, partly owing to the weak promoting effects of bulking agents on FQs degradation. The addition of bulking agents somehow hindered the reduction of ARGs within swine manure, whereas there were obvious reductions in the total relative abundance of ARGs in chicken manure with bulking agents added. Among the three bulking agents, sawdust was the most efficient enhancer for antibiotic removal in both manures, and rice husk exhibited the best performance on ARGs reduction in chicken manure. The relationship between antibiotics, ARGs and bacteria communities was subsequently delineated. Proteobacteria was proposed to play key roles on the effect of bulking agent addition on antibiotics and ARGs in swine manure. Particularly, the increased Xanthomonadaceae contributed much to the promoted antibiotic degradation as well as the high level of ARGs in swine manure with sawdust added. By contrast, the changes in dominant bacterial families by the addition of bulking agents into chicken manure were not strong enough to effectively enhance antibiotic removal, but largely influenced the ARGs abundance. The large reductions of Paenibacillaceae and Staphylococcaceae by rice husk addition were closely related to the reduced ARGs in chicken manure with rice husk added.
木屑、稻壳和蘑菇渣通常用作堆肥过程中的膨胀剂；本研究评估了它们在保持温度一致的条件下增强抗生素去除和抗生素抗性基因（ARGs）去除的潜力。结果表明，所有堆肥膨胀剂的添加都增加了猪粪中抗生素的去除率，增加率为 14.9%-33.4%；然而，它们对减少鸡粪中残留抗生素的效果较小，部分原因是膨胀剂对氟喹诺酮（FQs）抗生素降解的促进作用较弱。膨胀剂的添加在某种程度上阻碍了猪粪中 ARGs 的减少，而添加膨胀剂后鸡粪中 ARGs 的总相对丰度明显降低。在这三种膨胀剂中，木屑是两种粪便中抗生素去除的最有效增强剂，而稻壳在添加膨胀剂后对鸡粪中 ARGs 的减少表现出最好的效果。随后描绘了抗生素、ARGs 和细菌群落之间的关系。拟杆菌门被认为在膨胀剂添加对猪粪中抗生素和 ARGs 的影响中发挥关键作用。特别是，黄单胞菌科的增加对促进抗生素降解以及添加木屑后猪粪中高 ARGs 水平起到了重要作用。相比之下，膨胀剂添加到鸡粪中对优势细菌家族的变化不足以有效增强抗生素去除，但对 ARGs 丰度的影响较大。稻壳添加导致的巨大减少的芽孢杆菌科和葡萄球菌科与添加稻壳后鸡粪中减少的 ARGs 密切相关。
