School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China.
School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China; Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, Anhui 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui 230009, China.
Environ Pollut. 2024 Dec 15;363(Pt 1):125060. doi: 10.1016/j.envpol.2024.125060. Epub 2024 Oct 2.
Addressing the environmental threat of oxytetracycline (OTC) contamination, this study harnesses the bioremediation capabilities of Bacillus brevis MM2, a manganese-oxidizing bacterium from acid mine drainage. We demonstrate the strain's exceptional efficiency in degrading OTC under high manganese conditions, with complete removal achieved within 24 h. The degradation is facilitated by the production of Bio-MnOx, utilizing their high redox potential and large specific surface area, which significantly enhance the adsorption and oxidation of OTC. Advanced characterization techniques, including X-ray diffraction, scanning electron microscopy, High Resolution-Transmission Electronic Microscope and X-ray photoelectron spectroscopy, provide a detailed analysis of the structural and functional properties of Bio-MnOx. The study also reveals the crucial role of Mn(III) intermediates and reactive oxygen species in the OTC degradation process, with quenching experiments validating their substantial impact on efficiency. Laccase activity, a key manganese-oxidizing enzyme, is assessed spectrophotometrically, further highlighting the enzymatic contribution to Mn(II) oxidation and OTC breakdown. This research contributes valuable insights and approaches for the targeted bioremediation of OTC-contaminated aquatic environments, offering a promising strategy for combating pollution from antibiotics and analogous compounds.
针对土霉素（OTC）污染对环境造成的威胁，本研究利用了从酸性矿山排水中分离出的锰氧化菌短芽孢杆菌 MM2 的生物修复能力。我们证明了该菌株在高锰条件下高效降解 OTC 的能力，在 24 小时内即可完全去除。降解过程中产生的生物锰氧化物（Bio-MnOx）起到了促进作用，利用其高氧化还原电位和大比表面积，显著增强了 OTC 的吸附和氧化作用。先进的表征技术，包括 X 射线衍射、扫描电子显微镜、高分辨率透射电子显微镜和 X 射线光电子能谱，对 Bio-MnOx 的结构和功能特性进行了详细分析。该研究还揭示了 Mn(III)中间体和活性氧在 OTC 降解过程中的关键作用，通过猝灭实验验证了它们对效率的重要影响。通过分光光度法评估了漆酶活性，进一步强调了该酶在 Mn(II)氧化和 OTC 断裂中的作用。本研究为靶向生物修复 OTC 污染的水生环境提供了有价值的见解和方法，为对抗抗生素和类似化合物的污染提供了有前景的策略。
