摘要
      抗微生物耐药性正在成为全球人类健康的主要威胁之一，预计到2050年将导致1000万人死亡。集约化畜牧业和沼气消化物被认为是最大的ARG水库之一。尽管存在重大问题，但关于德国中小规模养猪场和沼气消化液中各种ARG的多样性和丰度，以及随后使用微滤（MF）-纳滤（NF）工艺去除它们的信息很少。在这里，我们报告了生粪肥和消化物样本中189个ARG的鉴定和定量，其中66个ARG在粪肥之间共享，53个ARGs在粪肥和发酵物样本之间共享。单个粪肥采样点报告的ARG总拷贝数最高为1.15×108拷贝/100µL。此外，我们发现37种ARGs的绝对浓度高于105拷贝/100μL。过滤结果表明，MF-NF工艺后，饲料中高浓度的ARGs（氨基糖苷抗性ARGs除外）表现出从3到5的高对数保留值（LRV）。此外，注意到LRV低于2，初始绝对ARG浓度≤103拷贝/100μL。因此，发现ARG的去除与其在生粪肥和消化物样品中的初始浓度成正比。因此，在NF的渗透物中仍然可以发现一些ARG（tetH，strB），其拷贝数高达104个/100μL。
Abstract
Antimicrobial resistances are emerging as one main threat to worldwide human health and are expected to kill 10 million people by 2050. Intensive livestock husbandry, along with biogas digestate, are considered as one of the biggest ARG reservoirs. Despite major concerns, little information is available on the diversity and abundance of various ARGs in small to large scale pig farms and biogas digestate slurry in Germany, followed by their consequent removal using microfiltration (MF)–nanofiltration (NF) process. Here, we report the identification and quantification of 189 ARGs in raw manure and digestate samples, out of which 66 ARGs were shared among manures and 53 ARGs were shared among both manure and digestate samples. The highest reported total ARG copy numbers in a single manure sampling site was 1.15 × 108 copies/100 µL. In addition, we found the absolute concentrations of 37 ARGs were above 105 copies/100 μL. Filtration results showed that the highly concentrated ARGs (except aminoglycoside resistance ARGs) in feed presented high log retention value (LRV) from 3 to as high as 5 after the MF-NF process. Additionally, LRV below 2 was noticed where the initial absolute ARG concentrations were ≤103 copies/100 μL. Therefore, ARG removal was found to be directly proportional to its initial concentration in the raw manure and in digestate samples. Consequently, some ARGs (tetH, strB) can still be found within the permeate of NF with up to 104 copies/100 μL.

https://www.mdpi.com/2077-0375/12/7/661