摘要

    抗生素抗性基因（ARG）的流行和传播已在全球范围内引起越来越多的关注。但是，人们很少了解ARGs在食物垃圾（FW）及其大规模生物处理系统中的命运和传播。在这里，我们研究了有氧发酵（AF）和厌氧共消化（AcoD）过程的两个主要FW处理系统中的初始FW和经过生物处理的FW。整数和ARG的总相对丰度从最初的FW到处理的FW显着增加。在靶向的ARG中，ermB和strB是主要的ARG，在所有样品中占总丰度的52.58–95.28％。 Mantel试验表明，整合素（intl1和intl2）与检测到的ARG呈正相关（Mantel试验，r = 0.24，p <0.05），表明整合素在FW治疗过程中对驱动ARG改变具有重要作用。 RDA结果表明，在最初的FW中，潜在的许多Firmicutes（96.55–99.77％）可能会增加blaOXA，strB和blaTEM的增殖，而在AF系统中，blaCTX-M和mefA可能会被变形杆菌富集（17.12–49.82％）。在AcoD系统中，拟杆菌（27.43–43.71％）可能增强了ermB，sul1，aadA和tetQ。考虑到ARGs处理系统中总ARGs的富集度较高（66.88±87.34倍）和接种的污泥，厌氧消化产品的资源利用应引起我们更多的关注。这些发现将加深我们对FW处理系统中ARG发生率和增殖的了解，并为指导生物处理FW的应用奠定基础。

    The prevalence and dissemination of antibiotic resistance genes (ARGs) have been globally gained increasing concerns. However, the fate and spread of ARGs in food waste (FW) and its large-scale biotreatment systems are seldomly understood. Here, we investigated the initial and biologically treated FW in two major FW treatment systems of aerobic fermentation (AF) and anaerobic co-digestion (AcoD) processes. The total relative abundances of integrons and ARGs significantly increased from initial FW to treated FW. Among targeted ARGs, ermB and strB were predominant ARGs, which accounted for 52.58–95.28% of total abundance across all samples. Mantel test indicated that integrons (intl1 and intl2) were positively and significantly correlated with detected ARGs (Mantel test, r = 0.24, p < 0.05), suggesting integrons display significant contributions on driving ARG alteration during FW treatment processes. RDA results indicated that blaOXA, strB and blaTEM were more likely to be proliferated by potential host of Firmicutes (96.55–99.77%) in initial FW, while blaCTX-M and mefA were potentially enriched by Proteobacteria (17.12–49.82%) in AF system and ermB, sul1, aadA and tetQ were possibly enhanced by Bacteroidetes (27.43–43.71%) in AcoD system. Consideration of the higher enriched abundance of total ARGs (66.88 ± 87.34 times) and the used inoculum sludge in AcoD-treated system, the resource utilization of anaerobically digested products should draw our more attentions. These findings would deepen our understanding of prevalence and proliferation of ARGs in FW treatment systems and serve as a foundation for guiding the application of biologically treated FW.

    https://www.sciencedirect.com/science/article/pii/S0160412020319681