Purification Approaches of Biocatalyst Applied for Cellulosic Biomass Breakdown

This review explores the research work on diverse cellulase purification approaches. Cellulase is an industrial biocatalyst applied to cellulosic breakdown. This biocatalyst has numerous applications in paper, food, fermentation, detergent, pharmaceuticals, textile, and distilling industries. Purification is an important prerequisite for any biocatalyst before the development of any enzyme-based effective applications. Cellulase purification is a multistep process selected on the basis of its biochemical and biophysical characteristics such as solubility, charge, size, and hydrophobicity/hydrophilicity. The success of any purification strategy employed for enzyme is evaluated on the basis of its purification fold, recovery percentage, reproducibility, economical feasibility, and time. Mostly, the pre-purification strategies involve fractionation, precipitation and ultrafiltration to attain high enzyme concentrate at the start of the purification process. The highly specific, secondary purification is achieved via chromatographic techniques, such as gel-filtration, ion exchange, adsorption, and affinity chromatography having different types of stationary and mobile phases. Certain unique purification techniques like isoelectric focusing, and electroendosmotic preparative electrophoresis have been also used. This review elaborates about various purification techniques and approaches available for the cellulase enzyme.