Production of Alpha Amylase by Bacillus subtilis Using Maize Husk as Substrate

Abstract

Aim: To produce alpha amylase by Bacillus subtilis using maize husk as substrate. Place and Duration of Study: Department of Microbiology, Ahmadu Bello University, Zaria between August 2016 and December 2016. Methodology: The proximate composition of the maize husk substrate was determined following standard procedures described by Association of Official Analytical Chemists (AOAC). The effects of incubation temperature, initial pH, incubation period and moisture content on the production of alpha amylase were investigated. Alpha amylase was produced by the B. subtlis isolate using maize husk as substrate by solid state fermentation under predetermined optimum fermentation conditions. The type of amylase produced was identified by sugar analysis using glucose and maltose as standards on thin layer chromatography (TLC). Results: The proximate analysis of the maize husk revealed percentages of ash (4.83%), crude protein (7.00%) and carbohydrates (60.37%) contents. All parameters optimized were found to significantly (P < 0.05) influence α-amylase production using maize husk. An overall yield of 51.65±0.13 U/g of alpha amylase was obtained under predetermined optimum fermentation conditions (35°C, pH 7.0, 72hrs and moisture content of 1:2). The product of starch hydrolysis on the TLC plate was found to appear as a spot with a retention factor (Rf) of 0.48 which is the same as that of standard maltose. Thus, indicating that the amylase produced was alpha amylase. Conclusion: Maize husk contains sufficient organic nutrients for growth and amylase production by B. subtilis. The study also revealed the potential of maize husk as substrate in the production of alpha amylase by B. subtilis.