Biochemical characterization of cellulases from psychrotolerant Penicillium canesense BPF4 and their potential application in the hydrolysis of selected plants biomass

Abstract

Cellulases from Psychrotrophic fungus P. canescens were characterized and tested their suitability for use in hydrolysis of pretreated plant biomass (wood of A. excelsa, wheat straw, saw dust and rice straw). Extracellular enzyme could be salted out with 50% and 60% ammonium sulphate saturation. The SDS-PAGE molecular mass of the enzyme was 75 kD. The FPases showed maximum activity at 50oC and at pH 9. The enzyme was metal sensitive, the Ca2+ ion inhibited nearly by 50%, Pb2+ affected the most nearly 45% of its activity. CMCase or endocellulase exhibited 100% activity at 4oC and at pH 8. It was extremely metal sensitive with Cu2+ causing nearly 75% inhibition. Cellobiases was thermotolerant yielding nearly 90% of the activity between 4oC-60oC and pH tolerant with more than 87 % activity between pH 5 to pH 11.The enzymes were also found metal tolerant.. The glucose upto 2.5% did not affect its activity. Lactose showed highest inhibition (about 35%) and glucose and cellobiose minimum (about 25%). The enzyme was highly active on microcrystalline cellulose, and also exhibited activity on xylan. Maximum saccharification was found to be on the fourth day, except saw dust which showed maximum 20% saccharification on the second day. newline