Towards high potential magnetic biocatalysts for on-demand elimination of pharmaceuticals

• Published in: Bioresource technology 2016-01, Vol.200, p.81-89
• Main Authors: Kumar, Vaidyanathan Vinoth, Cabana, Hubert
• Format: Article
• Language: English
• Subjects: Chitosan - chemistry; Cross-Linking Reagents - chemistry; Enzymes, Immobilized - chemistry; Enzymes, Immobilized - metabolism; Insolubilization; Laccase; Laccase - chemistry; Laccase - metabolism; Magnetics nanoparticles; Magnetite Nanoparticles - chemistry; Pharmaceutical Preparations - chemistry; Pharmaceutical Preparations - metabolism; Pharmaceuticals; Recycling; Stability; Temperature; Waste Disposal, Fluid - methods; Water Pollutants, Chemical - chemistry; Water Pollutants, Chemical - metabolism
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2015.09.100

•Chitosan/EDAC was used as crosslinking system for magnetic CLEAs laccase formation.•The resulting biocatalysts exhibited enhanced storage stability and recyclability.•MAC-CLEAs are promising for the treatment of pharmaceuticals from wastewaters.•Removal of 10 pharmaceuticals by laccase based bioprocess was achieved within 12h. The present study investigated the applicability of a laccase based bioprocess for the treatment of a mixture containing 13 selected pharmaceuticals. To do so, laccase was immobilized as cross-linked enzyme aggregates (MAC-CLEAs) on amine functionalized magnetic nanoparticles using chitosan/1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDAC) as the cross-linking system. The activity recovery of laccase reached 61.4% under the optimal conditions of MAC-CLEAs formation. The latter exhibited enhanced storage stability over one year at 4°C and showed better temperature resistance compared to its soluble counterpart. The biocatalysts were properly recycled and the catalytic activity recovery was good even after a hundred and fifty batch reactions. Complete removal of pharmaceuticals like acetaminophen, diclofenac, mefenamic acid, atenolol and epoxy carbamazepine and partial removal of fenofibrate, diazepam, trimethoprim, and ketoprofen by laccase was achieved within 12h of incubation, whereas efficient removal of indometacin required the presence of mediator.