Stabilization of β-Gal-3 ATCC 31382 on agarose gels: synthesis of β-(1→3) galactosides under sustainable conditions

Abstract

β-Gal-3 ATCC 31382 (β-Gal-3) was immobilized by multipoint covalent attachment on an agarose support using different enzyme orientations on its surface. The derivatives that showed more activity and stability were the ones bound to a Lys rich region on a monofunctional glyoxyl-agarose (GA) support. Also, immobilization was performed using a Glu + Asp rich region on a heterofunctional amino-glyoxyl-agarose (AMGA) support. The immobilized enzyme was characterized in terms of optimal pH and thermal stability, and its catalytic efficiency was tested on the synthesis of β-(1→3) galactosyldisaccharides. Reactions were performed in the presence of green solvents ([Bmim][PF₆] and 2HNND) with maximum conversion and maintained regioselectivity. Reusability assays under identical reaction conditions were also performed to find that GA immobilized enzyme retains about 90% of its activity after six batches with conversion yields above 75% when [Bmin][PF₆] was used as reaction media. Furthermore, green solvent recovery and recycling are achieved retaining catalytic activity and increased productivity.