Bilal Muhammad, Asgher Muhammad, Iqbal Hafiz M N, Hu Hongbo, Zhang Xuehong
Industrial Biotechnology Laboratory, Department of Biochemistry, University of Agriculture, Faisalabad, 38040, Pakistan.
State Key Laboratory of Microbial Metabolism, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.
Environ Sci Pollut Res Int. 2017 Mar;24(8):7035-7041. doi: 10.1007/s11356-017-8369-y. Epub 2017 Jan 14.
In this study, manganese peroxidase (MnP) from an indigenous white-rot fungus Ganoderma lucidum IBL-05 was insolubilized in the form of cross-linked enzyme aggregates (CLEAs) using various aggregating agents, i.e., acetone, ammonium sulfate, ethanol, 2-propanol, and tert-butanol, followed by glutaraldehyde (GA) cross-linking. The precipitant type, MnP, and GA concentrations affected the CLEAs activity recovery and aggregation yield. Among precipitants used, acetone appeared to be the most efficient aggregation agent, providing the highest activity recovery and aggregation yield of 31.26 and 73.46%, respectively. Optimal cross-linking was noticed using 2.0% (v/v) GA and 8:1 (v/v) MnP to GA ratio at 3.0 h cross-linking time under continuous agitation at 4 °C. The highest recovered activity and aggregation yield were determined to be 47.57 and 81.26%, respectively. The MnP-CLEAs, thus synthesized, were tested to investigate their bio-catalytic capacity for removing two known endocrine-disrupting chemicals (EDCs), e.g., nonylphenol and triclosan in a packed bed reactor system. The insolubilized MnP efficiently catalyzed the biodegradation of both EDCs, transforming over 80% in the presence of MnP-based system. A maximal of 100% decolorization was recorded for Sitara textile (SIT-based) effluent, followed by 95.5% for Crescent textile (CRT-based) effluent, 88.0% for K&N textile (KIT-based) effluent, and 84.2% for Nishat textile (NIT-based) effluent.
在本研究中，使用各种聚集剂，即丙酮、硫酸铵、乙醇、2-丙醇和叔丁醇，将本地白腐真菌灵芝IBL-05产生的锰过氧化物酶（MnP）以交联酶聚集体（CLEAs）的形式进行固定化，随后用戊二醛（GA）交联。沉淀剂类型、MnP和GA浓度影响CLEAs的活性回收率和聚集产率。在所使用的沉淀剂中，丙酮似乎是最有效的聚集剂，其活性回收率和聚集产率最高，分别为31.26%和73.46%。在4℃连续搅拌下交联3.0小时，使用2.0%（v/v）GA和8:1（v/v）的MnP与GA比例时观察到最佳交联效果。最高回收活性和聚集产率分别确定为47.57%和81.26%。对如此合成的MnP-CLEAs进行测试，以研究它们在填充床反应器系统中去除两种已知内分泌干扰化学物质（EDC），即壬基酚和三氯生的生物催化能力。固定化的MnP有效地催化了两种EDC的生物降解，在基于MnP的系统存在下转化率超过80%。Sitara纺织（SIT基）废水的脱色率最高达到100%，其次是Crescent纺织（CRT基）废水的95.5%、K&N纺织（KIT基）废水的88.0%和Nishat纺织（NIT基）废水的84.2%。
