摘要

       粪便处理技术正在迅速发展，以尽量减少周围环境的富营养化，并可能减少抗生素和抗生素抗性基因（ARGs）进入环境。虽然实验室和中试规模的粪便处理系统具有良好的效果，但在连续输入粪便的全规模系统中，抗生素和精氨酸的去除率尚未得到评估。治疗对ARGs的作用同样缺乏。本研究探讨了磺胺类药物、四环素类药物、四环素降解产物及相关的精氨酸在大型高级厌氧消化池（AAD）中的发生与转化，该消化池接受连续的粪便和抗生素输入。在整个AAD系统中收集粪便样本，以评估基线抗生素和精氨酸输入（原肥）、湿度化（巴氏灭菌后的粪便）和厌氧消化（消化后的粪便）对抗生素和精氨酸水平的影响。采用液相色谱-串联质谱（LC-MS/MS）分析抗生素，定量聚合酶链反应（Q-PCR）分析ARGs-tet（O）、tet（W）、sul1和sul2。处理后粪液中金霉素、土霉素、四环素及其降解产物的浓度显著降低（p <0.001），同时粪固体含量显著增加（p <0.001）。这些结果表明吸附是AAD过程中四环素类化合物的主要去除途径。有机肥固体中金霉素和四环素的表聚物与总残留量之比显著降低，进一步表明降解受到解吸限制。此外，在没有磺胺类抗生素的情况下，AAD后sul1和sul2拷贝数明显减少（p<0.001），而四环素类耐药基因保持不变。此外，还对采用自然通风和液固分离处理的奶牛场进行了横断面研究，以比较AAD中发现的抗生素和精氨酸的水平与普通粪便管理系统中的水平。不同农场间生粪肥中抗生素浓度差异较大，而精氨酸含量差异较小。然而，在三种不同的粪便管理系统的废水中，抗生素和精氨酸（tet（W）除外）的含量差异显著（p<0.01）。

        Manure treatment technologies are rapidly developing to minimize eutrophication of surrounding environments and potentially decrease the introduction of antibiotics and antibiotic resistant genes (ARGs) into the environment. While laboratory and pilot-scale manure treatment systems boast promising results, antibiotic and ARG removals in full-scale systems receiving continuous manure input have not been evaluated. The effect of treatment on ARGs is similarly lacking. This study examines the occurrence and transformation of sulfonamides, tetracyclines, tetracycline degradation products, and related ARGs throughout a full-scale advanced anaerobic digester (AAD) receiving continuous manure and antibiotic input. Manure samples were collected throughout the AAD system to evaluate baseline antibiotic and ARG input (raw manure), the effect of hygenization (post-pasteurized manure) and anaerobic digestion (post-digestion manure) on antibiotic and ARG levels. Antibiotics were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the ARGs tet(O), tet(W), sul1 and sul2 were analyzed by quantitative polymerase chain reaction (Q-PCR). Significant reductions in the concentrations of chlortetracycline, oxytetracycline, tetracycline and their degradation products were observed in manure liquids following treatment (p < 0.001), concomitant to significant increases in manure solids (p < 0.001). These results suggest sorption is the major removal route for tetracyclines during AAD. Significant decreases in the epimer-to-total residue ratios for chlortetracycline and tetracycline in manure solids further indicate degradation is desorption-limited. Moreover, sul1 and sul2 copies decreased significantly (p < 0.001) following AAD in the absence of sulfonamide antibiotics, while tetracyclines-resistant genes remained unchanged. A cross-sectional study of dairy farms utilizing natural aeration and liquid-solid separation treatments was additionally performed to compare levels of antibiotics and ARGs found in AAD with the levels in common manure management systems. The concentration of antibiotics in raw manure varied greatly between farms while minimal differences in ARGs were observed. However, significant (p < 0.01) differences in the levels of antibiotics and ARGs (except tet(W)) were observed in the effluents from the three different manure management systems.

        https://www.sciencedirect.com/science/article/pii/S0269749117352260?via%3Dihub