摘要

       土壤中的抗生素和抗生素抗性基因 (ARG) 可以通过食物链影响人类健康。 Biochar 是一种土壤改良剂，但其对 ARG 以及与土壤和蔬菜相关的微生物群落的影响尚不清楚。因此，我们建立了三个生菜盆栽培养实验，即 O300：300 mg/kg 土霉素 (OTC)、BO300：300 mg/kg OTC + 2% biochar，以及不含 OTC 或 biochar 的对照。我们发现在 BO300 下，与 O300 相比，生菜叶、根和土壤中 ARGs 的相对丰度分别降低了 51.8%、43.4% 和 44.1%。 intI1 在土壤和生菜中含量很高，并且它与一些 ARG（tetW、ermF 和 sul1）同时发生。冗余分析和网络分析表明细菌群落演替是影响ARGs和intI1变异的主要机制。由于土壤和生菜的生物炭处理导致厚壁菌门的减少是导致去除叶片中四环素抗性基因的主要因素。 Biochar 的应用导致人类致病菌（HPB）的消失，这与 ermF 和 ermX 的丰度显着相关。综上所述，生物炭是一种有效的农田改良剂，可以减少抗生素、ARGs和HPB的丰度，以确保蔬菜安全，保护人类健康。

       Antibiotics and antibiotic resistance genes (ARGs) in soil can affect human health via the food chain. Biochar is a soil amendment but its impacts on ARGs and the microbial communities associated with soil and vegetables are unclear. Therefore, we established three lettuce pot culture experiments, i.e., O300: 300 mg/kg oxytetracycline (OTC), BO300: 300 mg/kg OTC + 2% biochar, and a control without OTC or biochar. We found that under BO300, the relative abundances of ARGs were reduced by 51.8%, 43.4%, and 44.1% in lettuce leaves, roots, and soil, respectively, compared with O300. intI1 was highly abundant in soil and lettuce, and it co-occurred with some ARGs (tetW, ermF, and sul1). Redundancy analysis and network analysis indicated that the bacterial community succession was the main mechanism that affected the variations in ARGs and intI1. The reduction of Firmicutes due to the biochar treatment of soil and lettuce was the main factor responsible for the removal of tetracycline resistance genes in leaves. Biochar application led to the disappearance of human pathogenic bacteria (HPB), which was significantly correlated with the abundances of ermF and ermX. In summary, biochar is an effective farmland amendment for reducing the abundances of antibiotics, ARGs, and HPB in order to ensure the safety of vegetables and protect human health.

https://www.sciencedirect.com/science/article/abs/pii/S026974911630793X