Kinetics-bolstered catalytic study of a high performance lipase-immobilized nanofiber membrane bioreactor

Abstract

Enzyme-immobilized membrane bioreactors combine biocatalysis with separation, and thus have generated interest among applied researchers. Despite the advantages of enzyme-immobilized membrane bioreactors, some issues associated with the membrane and operation parameters still remain to be addressed in order to achieve scale-up of such systems. We report the fabrication of a biphasic lipase-immobilized nanofiber membrane bioreactor with high catalytic performance. A poly(acrylonitrile-co-acrylic acid) non-woven nanofiber membrane was prepared by electrospinning and lipase from Candida rugosa was covalently coupled to it via an activation process by N-(3-dimethylaminopropyl)-N′-ethyl-carbodiimide hydrochloride/N-hydroxy-succinimide. The influences of membrane diameters and operation variables on bioreactor efficiency were studied using the catalytic hydrolysis of olive oil as the model reaction. Furthermore, a pseudo first order model contributed to the evaluation of lipase performance in a more standardized way. A bioreactor activity of 1.85 × 10⁴ U g⁻¹ was obtained under optimum operation conditions; also, the catalytic system exhibited good operational and recycling stability.