摘要

灭活抗生素耐药菌( ARB )和去除抗生素耐药基因( ARGs )是防止它们向环境扩散的重要措施。以往的研究都是从水溶液和污泥中去除ARB和ARGs，但是，目前还没有取得令人满意的结果。本研究调查了二氧化钛光催化能否降低宿主ARB，耐甲氧西林金黄色葡萄球菌（MRSA）和绿脓假单胞菌内的两种ARGs，mecA和ampC。还研究了H2O2的加入和基质效应对ARB和ARGs的去除效果。二氧化钛薄膜对ARB的钝化和ARGs的去除均有良好的效果。在6 mJ / cm2和12mj / cm2的UV254能量密度下，二氧化钛分别实现了约4.5 - 5.0和5.5 - 5.8 log ARB的降低。对于ARGs，在120 mJ / cm2的UV254能量密度下，在二氧化钛存在情况下，mecA降低5.8 log，ampC降低4.7 log。增加H2O2用量可提高ARB和ARGs的去除率。结果还表明，二氧化钛光催化能同时去除细胞内和细胞外的ARGs。本研究为从水溶液中去除ARB和ARGs提供了一种潜在的替代方法。

Inactivating antibiotic resistant bacteria (ARB) and removing antibiotic resistance genes (ARGs) are very important to prevent their spread into the environment. Previous efforts have been taken to eliminate ARB and ARGs from aqueous solution and sludges, however, few satisfying results have been obtained. This study investigated whether photocatalysis by TiO2 was able to reduce the two ARGs, mecA and ampC, within the host ARB, methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, respectively. The addition of H2O2 and matrix effect on the removal of ARB and ARGs were also studied. TiO2thin films showed great effect on both ARB inactivation and ARGs removal. Approximately 4.5-5.0 and 5.5–5.8 log ARB reductions were achieved by TiO2under 6 and 12 mJ/cm2 UV254 fluence dose, respectively. For ARGs, 5.8 logmecA reduction and 4.7 log ampC reduction were achieved under 120 mJ/cm2UV254 fluence dose in the presence of TiO2. Increasing dosage of H2O2enhanced the removal efficiencies of ARB and ARGs. The results also demonstrated that photocatalysis by TiO2 was capable of removing both intracellular and extracellular forms of ARGs. This study provided a potential alternative method for the removal of ARB and ARGs from aqueous solution.

https://www.sciencedirect.com/science/article/pii/S0304389416309396