Vaithyanathan Vasanth Kumar, Vaidyanathan Vinoth Kumar, Cabana Hubert
University of Sherbrooke Water Research Group, Environmental Engineering Laboratory, Faculty of Engineering, Université de Sherbrooke, Sherbrooke, QC, Canada.
Integrated Bioprocessing Laboratory, School of Bioengineering, SRM Institute of Science and Technology (SRM IST), Kancheepuram, India.
Front Bioeng Biotechnol. 2022 Feb 11;9:770435. doi: 10.3389/fbioe.2021.770435. eCollection 2021.
In this study, was grown on municipal biosolids (BS) as the substrate to produce laccase for the removal of pesticides (fungicides, herbicides, and insecticides) from wastewater. Among the various types of BS tested, sterilized biosolids were the most promising substrate for laccase production by with a maximal laccase activity (162.1 ± 21.1 U/g dry substrate), followed by hygenized biosolids (96.7 ± 17.6 U/g dry substrate), unsterilized biosolids (UBS) (31.9 ± 1.2 U/g dry substrate), and alkali-treated biosolids (8.2 ± 0.4 U/g dry substrate). The ultrasound-assisted extraction of this enzyme from fermented UBS was carried out with 0.1 M phosphate buffer at pH 7.0, which increased the enzyme activity of the crude extract by 30%. To test the catalytic potential of the biocatalyst in real matrices, 1 U/ml of recovered crude laccase extract was applied for 24 h for the removal of 29 pesticides (nine fungicides, 10 herbicides, and 10 insecticides) either separately or as a mixture from spiked biologically treated wastewater effluent. When treated with crude enzyme extract, high-priority herbicides metolachlor and atrazine were completely removed, while 93%-97% of the insecticides aldicarb, spinosad, and azinphos-methyl and up to 91% of kresoxim-methyl were removed. Promising results were obtained with BS-derived crude enzyme extract exhibiting improved pesticides removal, which may be due to the mediator effect resulting from the catalytic transformation of other molecules in the cocktail. The results demonstrated a promising integrated bioprocess for the removal of pesticides in wastewater using crude laccase obtained from BS.
在本研究中，[具体菌种名称未给出]以城市生物固体（BS）为底物生长，用于生产漆酶以去除废水中的农药（杀菌剂、除草剂和杀虫剂）。在测试的各种类型的生物固体中，灭菌生物固体是[具体菌种名称未给出]生产漆酶最有前景的底物，漆酶活性最高（162.1±21.1 U/g干底物），其次是氢化生物固体（96.7±17.6 U/g干底物）、未灭菌生物固体（UBS）（31.9±1.2 U/g干底物）和碱处理生物固体（8.2±0.4 U/g干底物）。用0.1 M pH 7.0的磷酸盐缓冲液对发酵后的UBS进行超声辅助提取该酶，这使粗提物的酶活性提高了30%。为了测试生物催化剂在实际基质中的催化潜力，将1 U/ml回收的粗漆酶提取物应用24小时，以单独或混合形式从加标的生物处理废水流出物中去除29种农药（9种杀菌剂、10种除草剂和10种杀虫剂）。用粗酶提取物处理时，高优先级除草剂异丙甲草胺和阿特拉津被完全去除，而杀虫剂涕灭威、多杀菌素和甲基谷硫磷的93%-97%以及甲基苯并咪唑甲环唑高达91%被去除。从生物固体中获得的粗酶提取物在农药去除方面表现出改善的效果，取得了有前景的结果，这可能是由于混合物中其他分子的催化转化产生的介体效应。结果表明，使用从生物固体中获得的粗漆酶去除废水中农药的综合生物工艺具有前景。
