The concept of this project bothers around converting the BSG waste to wealth in the form of research products such as cellulase, composts, xylitol, and Animal feed. The study has extensively paid attention to only cellulase production using BSG as carbon source. The research group is yet to commence research actions on the xylitol, composts, and animal feed from BSG.  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 production of cellulase from Aspergillus flavus isolated from Brewers’ Spent Grain (BSG) undergoing bio-deterioration was carried out. Two different enzyme production media containing either yeast extract or potassium nitrate (KNO3) served as source of Nitrogen to the Aspergillus flavus. 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%, 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. Bacterial  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 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. The Crude activity of the potassium nitrate (KNO3) option (28,170 Units) was significantly higher than the Crude Cellulase from yeast extract option (18,600Units). On partial purification, 60% Ammonium sulphate precipitation gave the best Cellulase activity. The optimum pH of Aspergillus flavus Cellulase was 6.0, while the optimum temperatures were between 500C to 600C. Tolerance to some alkali and alkaline –earth metals was also established, and co-factor behaviour of manganese ion to this cellulase was also established. This also calls for public-private partnership between research institutes and Industries in Nigeria in order to carry ou application studies, and commercialise this product (cellulase).