Development of alternative disinfection methods to inactivate extracellular antibiotic resistance genes in aquatic environments

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K14858
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 22060:Environmental systems for civil engineering-related
• Research Institution: Kitasato University
• Principal Investigator: Amarasiri Mohan 北里大学, 医療衛生学部, 講師 (50815537)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: 薬剤耐性遺伝子 / 塩素消毒 / 過酢酸消毒 / 過ギ酸消毒

Outline of Final Research Achievements

We evaluated the inactivation efficiency of extracellular antibiotic resistance genes (ARGs) by free chlorine (Cl), peracetic acid (PAA), and performic acid (PFA) using plasmid pUC19, which carries ampicillin resistant gene, as a model. Reduction of viable extracellular ARGs was evaluated by calculating the reduction of transformation frequency of pUC19 exposed to disinfectants with Escherichia coli competent cells. Free chlorine showed high and time-dependent disinfection effect even at 1 ppm concentration. For PAA and PFA, the inactivation efficiency increased with initial concentration and time dependency was almost negligible. A 2.3 and 2.9 log reductions of viable pUC19 was observed by PAA and PFA. PAA and PFA has not shown to generate harmful disinfection by products and therefore can be considered as alternative disinfectants usable in decentralized facilities to minimize the spread of antibiotic resistance.

Free Research Field

環境工学

Academic Significance and Societal Importance of the Research Achievements

本研究の結果では、PAAおよびPFAの細胞外ARG不活化効率が遊離塩素に匹敵することを確認した。さらに、PAAとPFA消毒の場合塩素消毒で生成される有害な消毒副産物も生成されない。したがって、PAAとPFAは、薬剤耐性遺伝子の蔓延を最小限に抑えるために分散型施設で使用できる代替消毒剤と見なすことができる。厳格な薬剤消費規制なしに、低中所得国でさらに開発および使用することができます。 本技術は、さらに開発され、厳格な薬剤消費規制がない低中所得国で、使用される可能性がある。