Elucidating the potential of cellulases isolated from a locally isolated strain (NSF-2) in paper and pulp industry

Abstract

The potential of enzyme cellulases which are known to all has made it pave its way in the field of present-day biotechnology and bio-based emerging industries. For the purpose of human consumption of enzymes, it makes it even more demanding to perform highly precised purification method. Our study deals with the characterization and applicability of cellulases fabricated by a locally isolated strain (NSF-2). The enzyme was purified using standard purification techniques. The isolated enzyme was observed to be of molecular weight 75KDa Purified enzyme showed the best activity at pH5, 50 °C and 3 % substrate concentration. The gene isolated from cellulase enzyme of about 1.2 Kb was amplified from selected isolate. Salts like SDS, urea, EDTA were perceived to have a regressive effect on enzyme activity while tween 20 and tween 100 were neutral towards enzyme. Hg2+ was found to be the most potent inhibitor and Ca2+ was found to be the most potent inhibitor and most significant activator of the enzyme respectively. The waste paper was deinked with isolated enzyme, sodium silicate (5 %) and NaOH (2 %). Various techniques like FTIR, SEM, fluorescence micrographs and fluorescence spectroscopy were performed to study the quality of the deinked paper. The results obtained for cellulase deinking were comparable to sodium silicate treatment but better as compared to NaOH treated paper. Although, the results of enzymatic deinking were similar to the results obtained in sodium silicate treatment but the enzymatic technology proved to be an advantageous technology as compared to chemical deinking as a reduction in dewatering step, declined chemical load in waste water, save capital cost and less energy consumption. The enzyme was found to be highly suitable for application in deinking industries which are in accordance with the observations.