Variable effects of oxytetracycline on antibiotic resistance gene abundance and the bacterial community during aerobic composting of cow manure
Variable effects of oxytetracycline on antibiotic resistance gene abundance and the bacterial community during aerobic composting of cow manure
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DOI：
10.1016/j.jhazmat.2016.05.002
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发表时间：
2016-09-05
影响因子：
13.6
通讯作者：
Duan, Man-Li
中科院分区：
文献类型：
--
作者：
Qian, Xun;Sun, Wei;Duan, Man-Li
畜禽粪便通常进行好氧堆肥，但对不同浓度抗生素在堆肥过程中抗生素抗性基因（ARGs）的变化知之甚少。本研究比较了三种浓度土霉素（OTC； 10、60和200 mg/kg）对堆肥过程中ARGs和细菌群落演替的影响。堆肥过程中，OTC处理与对照间各ARG相对丰度的变化趋势非常相似。堆肥后，tetC、tetX、硫、硫2和intI1的RAs增加了2 ~ 43倍，而tetQ、tetM和tetW的RAs下降了44 ~ 99%。添加200 mg/kg OTC显著提高了tetC和intI1的绝对丰度和RAs，同时也显著提高了tetM、tetQ和drfA7的绝对丰度和RAs。在不同处理下，细菌群落可根据堆肥时间进行分组。最高浓度的OTC对细菌群落的影响更持久。在本研究中，细菌群落的演替似乎比抗生素的存在对堆肥过程中ARGs的变化有更大的影响。好氧堆肥不能有效地减少大部分ARGs，因此堆肥产品应被视为ARGs的重要储存库。(C) 2016 Elsevier B.V.版权所有
Livestock manure is often subjected to aerobic composting but little is known about the variation in antibiotic resistance genes (ARGs) during the composting process under different concentrations of antibiotics. This study compared the effects of three concentrations of oxytetracycline (OTC; 10, 60, and 200 mg/kg) on ARGs and the succession of the bacterial community during composting. Very similar trends were observed in the relative abundances (RAs) of each ARG among the OTC treatments and the control during composting. After composting, the RAs of tetC, tetX, sull, sul2, and intI1 increased 2-43 times, whereas those of tetQ, tetM, and tetW declined by 44-99%. OTC addition significantly increased the absolute abundances and RAs of tetC and intI1, while 200 mg/kg OTC also enhanced those of tetM, tetQ, and drfA7. The bacterial community could be grouped according to the composting time under different treatments. The highest concentration of OTC had a more persistent effect on the bacterial community. In the present study, the succession of the bacterial community appeared to have a greater influence on the variation of ARGs during composting than the presence of antibiotics. Aerobic composting was not effective in reducing most of the ARGs, and thus the compost product should be considered as an important reservoir for ARGs. (C) 2016 Elsevier B.V. All rights reserved.