磺胺和四环素类抗生素对大肠杆菌联合突变效应的研究

抗生素的滥用造成的环境安全问题已不可忽视,关于抗生素联合毒性效应研究较多,但联合突变效应研究较少。因此,本文以大肠杆菌为受试生物,研究了2种磺胺类抗生素(磺胺氯哒嗪(SCP)、磺胺二甲嘧啶(SMZ))和3种四环素类抗生素(二甲胺四环素(MH)、盐酸四环素(TH)和盐酸强力霉素(DH))单一及联合暴露时对大肠杆菌的突变效应。结果表明:在单一暴露下,磺胺类抗生素会促进大肠杆菌的突变效应,四环素类抗生素没有明显的促进作用;联合暴露下,磺胺类抗生素对大肠杆菌突变效应为相加,磺胺和四环素类抗生素对大肠杆菌突变效应为拮抗。本研究初步探索了抗生素对大肠杆菌的联合致突变风险,为今后环境中抗生素混合暴露的生态风险评价和抗生素污染控制标准制定提供一种理论支撑。

Combined Mutation Effect of Sulfonamide and Tetracycline Antibiotics Against Escherichia coli

The abuse of antibiotics has caused a series of environmental problems, which should not be ignored. Many studies have been conducted to investigate the combined toxicity of antibiotics, but few of them have ever focused on the joint effects on the bacterial resistance mutation. The present research studied the individual and joint effects of two sulfonamide antibiotics, (sulfachlorpyridazine (SCP), sulfamethazine (SMZ)) and three tetracycline antibiotics (minocycline (MH), tetracycline hydrochloride (TH) and doxycycline hydrochloride (DH)) on the mutation of E. coli. The results showed that: upon the individual exposure, sulfonamide antibiotics could promote the mutation of E. coli, while the tetracycline antibiotics have no obvious promotion; upon the combined exposure, binary sulfonamide antibiotics presented additive joint effects, whilst the mixtures of sulfonamide and tetracycline presented antagonistic joint effects on the resistance mutation of E. coli. This study preliminarily explored the risk of joint exposure of antibiotics on the resistance mutation of E. coli, providing a theoretical support for the ecological risk assessment on the joint effects of antibiotics in the real environment and attributing to the formulation of pollutant control standards in the future.