Aforetime, corn, rice, sorghum, wheat and cassava are the main sources of glucose production. But recently, agricultural
wastes and grasses are trending alternative biomasses for glucose production in quest to avoid food -energy conflict. In this
work, the effects of pretreatment (hot water, 0.2 M NH4OH, 1 M NH4OH and 3 M NH4OH respectively) and various hydrolysis
variables (time, 8 72 hours; pH, 3.5 6.5; temperature, 30 60oC; particle size range, 75 600 μm; substrate
concentration, 5 100 g/l; and cell loading, 0.1 1.0 g) on glucose production from elephant grass have been investigated.
The elephant grass was characterized to determine its constituents i.e. cellulose, hemicellulose and lignin contents. The
traditional unifactorial approach was followed to obtain the process optimum variables as 24 hours, 45 oC, 4.5, 20 g/l, 100
150 μm and 1.0 g for hydrolysis time, temperature, pH, initial substrate concentration, particles size range, and cell loadin g
respectively. Glucose production at the obtained optimum conditions gave a glucose yield of 82.6 %. A kinetic model, is
established based on Michelis- Mentens approach. The glucose yield obtained showed that the process is viable and the rate
equation was statistically consistent, with correlation coefficient value of 0.9963, which is good for reactor design and process
analysis.
Key words: Biomass, Aspergillus niger, enzymatic hydrolysis, glucose, kinetic model
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