Abstract

Cellulose from Brewers Spent Grain (BSG) and crystalline cellulose were utilized as sole carbon source for the submerged production of Cellulase. A total of 21 bacterial isolates were obtained from Brewers Spent Grain undergoing deterioration. Out of the 21 isolates, 7 bacterial isolates showed various degrees of Cellulase production on plate assay (Nutrient Agar +2% (W/V) Cellulose) by their zones of clearance of Cellulose. The Brewers Spent Grain was characterized for its composition, and its moisture content, Crude Fibre, Fat, Protein, Ash and Total carbohydrate were 17.62%, 13.94%, 8.08%, 25%, 3.68% and 31.68% respectively. Cellulase production screening of bacterial isolates showed that Bacillus species strain B223 had the highest zone of clearance (2.8cm ± 0.02), and was used for the submerged Cellulase production. Microbial population dynamics in the enzyme production medium in the 250ml capacity Erlenmeyer flasks containing BSG cellulose increased progressively from zero hour to the 120 hour. pH of the BSG cellulose medium increased from 5.28 to 6.89, while the set-up containing crystalline cellulose had its pH increased from 5.28 to 7.46. Crude cellulase activity of the cellulase in Filter paper Units (FPU) for the cellulase produced from BSG Cellullose ranged from 328 FPU, 2749PU, 32166FPU, 31910 FPU, and 33130 FPU at zero hour, 24hour, 48hour, 72 hour, 96 hour and 120 hour of fermentation respectively. The optimum pH for the production of Cellulase was 6.89. Specific Cellulase activities of Cellulase produced using BSG cellulose and Crystalline cellulose were between 12.45-4319.4 (Unit/Mg) and 19.6 -5711 (Unit/Mg) respectively. Cellulases are industrial enzymes with broad applications, and production using raw materials like cellulose from Brewers Spent Grain makes the enzyme cost effective, and converts the waste (BSG) to wealth. Further research actions are on-going to purify the crude Cellulase.