Optimization and purification of cellulase produced by Penicillium decumbens and its application

Abstract

Background and objectives Cellulases are an enzyme group based on catalytic action. They include endocellulase, exocellulase, beta glucosidase, cellulose phosphorylases, and oxidative cellulases. This work was aimed at the production of cellulase by fungal strains from Penicillium sp. Selection of the best organism that gives the highest productivity of the enzyme, examination of the cellulase production under the optimum conditions, purification of cellulase, identification by high-performance liquid chromatography, and its application in clarification and yield increase of apple juice were also studied. Materials and methods Three strains of Penicillium sp. were examined using the method of Congo red for cellulase production. The factors affecting cellulase production by fungus Penicillium decumbens were identified. Cellulase produced by P. decumbens was purified using ammonium sulfate precipitate (80% saturation) followed by ion exchange chromatography by Sephadex G-200. High-performance liquid chromatography technique was used to measure the purity of cellulase produced from P. decumbens. The cellulase enzyme was used to increase the yield of apple juice and apple juice clarification, as examples of its application in the food industry. Results and conclusion The P. decumbens colony proved to have the largest decolorization zone, and the cellulase produced was a large amount (21.5 U/ml). The highest activity of cellulase was seen in the media containing 50% carboxymethylcellulose and 50% dates molasses waste (Dibs) as carbon source after incubation for 6 days, and the optimum pH and temperature for the production cellulase were pH 4.0 at 30°C. Utilization of 80% ammonium sulfate gave pure enzyme cellulase (38.25 U/ml) and has a high degree of specific activity (25.5 U/mg protein). Cellulase activity of 42 U/ml and the degree of specific activity of 46.6 U/mg protein, with a 4.3-fold purification of cellulase, with 42% recovery from the crude cellulase, was obtained with Sephadex G-200. The results revealed an increase in the quantity of produced apple juice treated by cellulase enzyme.