Suitability of organic solvent and cholinium based ionic liquid activated novel lignolytic enzymes of H. aswanensis for enhanced Kalson lignin degradation

Present study focuses on the organic solvent and ionic liquid compatibility of lignolytic enzymes produced from H. aswanensis strain ABC_IITR. Lignin peroxidase (LiP), Manganese Peroxidase (MnP) and Laccase (Lac) obtained by Solid State Fermentation (SSF) of wheat bran. In this work, lignolytic enzymes subjected to 20-40% (v/v) organic solvents, metals ions, and cholinium laurate based ionic liquid (CLIL). Use of 40% (v/v) of pyridine along with 1.5 M NaCl and 0.15 mM CLIL in reaction system increased the bio-catalytic activity of lignolytic enzymes whereas metal ions like Fe increased LiP and MnP activities, and Cu enhanced laccase activity compared to control. The inherent stability of lignolytic enzymes in CLIL was not affected significantly whereas it decreased in pyridine reaction system. Further, in Kalson lignin degradation study, higher degradation achieved in CLIL (generate less saline waste) as compared to 40% (v/v) pyridine reaction system. In MnP catalyzed system, use of Glutathione (GSH) as mediator had resulted in maximum reduction of lignin weight of 40.84 and 31.83% in 40% (v/v) pyridine (1.5 NaCl) and 0.15 mM CLIL, respectively. This is the first report on lignolytic enzymes of haloarchaea with capability to get activated in organic solvent and cholinium laurate based ionic liquid. (C) 2020 Published by Elsevier B.V.