INCREASE IN GLUCOSE GENERATION FROM THE BIOCONVERSION EFFICIENCY OF SUCCESSIVE PRETREATMENT OF DIFFERENT NIGERIAN SAWDUST LIGNOCELLULOSIC WASTES

N. A. Ndukwe; W. O. Okiei, B. I. Alo; J. P. H. van Wyk, T. M. Mamabola; C. C. Igwe

N. A. Ndukwe Department of Chemical Sciences, College of Basic and Applied Sciences, Mountain Top University, Magoki Ogun State.
W. O. Okiei, B. I. Alo Department of Chemistry, University of Lagos, Akoka, Lagos, Nigeria.
J. P. H. van Wyk, T. M. Mamabola Department of Pharmacology and Therapeutics, Sefako Makgatho Health Sciences University, Pretoria North, Gauteng Province, South Africa
C. C. Igwe Chemical, Fibre and Environmental Technology Department, Federal Institute of Industrial Research, Oshodi, Lagos, Nigeria

Keywords: Biomass pretreatment, Lignocellulosic Waste, Bioconversion efficiency, Trichoderma viride cellulase, Glucose generation

Abstract

Biomass pretreatment plays an important role in lignocellulose utilization for glucose generation and subsequent bioconversion processes. The inherent properties of sawdust lignocellulosic biomass make them recalcitrant to enzymatic catalysis and thereby reduce its bioconversion efficiency. Effective pretreatment option enhances cellulose accessibility and susceptibility to enzymatic hydrolysis into glucose, biofuels and other desired chemicals. Investigation into the bioconversion efficiency of different sawdust lignocellulosic biosubstrates from a successive biomass pretreatment process and the resultant increase in glucose generation has been carried out. The amounts of glucose obtained from sawdust of twenty Nigerian tropical hardwoods at different biomass concentrations of 4, 10, 20, 40 and 60mg/mL after Kraft pretreatment process and Trichoderma viride cellulase interaction were 1.41, 2.29, 2.70, 2.46 and 1.96 mg/mL respectively for M. excelsa wood sawdust. The successive pretreatment of each of the Kraft cellulose with hydrogen peroxide at constant incubation period and enzyme treatment resulted in enhanced glucose concentrations of 3.26, 4.88, 4.65, 8.72 and 7.84mg/mL from the same M. excelsa sawdust to give 131%, 113%, 72%, 225% and 300% increase in glucose generation. The effect of a successive Kraft and hydrogen peroxide pretreatments on the biosubstrates led to large percentage increase in glucose formation from all the twenty-wood sawdust examined.