Production of bacterial amylase by Bacillus species isolated from rice husk dumpsites in Sokoto metropolis, Nigeria

Abstract

Ten grams (10 g) of soil sample was obtained from a rice husk dumpsite in Sokoto metropolis and analyzed. The species isolated were Bacillus licheniformis, Bacillus lentus and Bacillus megaterium. The Bacillus species isolated were screened for amylolytic activities. The isolate with the widest zone of clearance (A1 ) was selected for further analysis. The highest activity was observed in B. licheniformis (2.00±0.01 mm) followed by B. lentus (1.96±0.40 mm) and B. megaterium (1.70±0.18 mm) had the least activity. Amylase activity was determined using DNS method. The optimum temperature for the activity of the amylase produced was obtained at 90 °C with a concentration of 0.373 mg/ml. Optimum pH activity was obtained at 4.0 with a concentration of 0.376 mg/ml. Bacillus licheniformis has the greatest potential for producing amylase than the other isolates and rice husk can be exploited for amylase production. The B. licheniformis strain produced thermostable alpha-amylase with characteristics suitable for application in starch processing and other food industrie