Biodegradation of cornhusk by Bacillus cereus isolated from soil.

Abstract

The isolation and identification of cellulolytic bacteria from soil for the biodegradation of cornhusk was carried out in this study. Cornhusk and soil samples were collected from a dump site in Minna, Nigeria. Carboxymethylcellulose (CMC) medium was inoculated with 1 ml of diluted soil by pour-plate method; the isolate with highest hydrolytic zone was selected and identified using standard cultural, biochemical and molecular tests. Cornhusk was sterilized in an autoclave prior to degradation tests using the isolate. The degradation potential of cornhusk by the isolate was measured using percentage cellulose loss. The effect of temperature (4oC, 28oC and 40oC) on the degradation of the cornhusk was determined for 28 days. The highest degradation (80.55±0.77 %) was observed at 40oC followed by 68.53±0.74 % at 4oC while the least was 37.90±0.14 % at 28oC. The control (uninoculated cornhusk) had percentage degradation of 2%, 5% and 8% at 4oC, 28oC, and 40oC respectively. The organism with the highest degradation potential was identified as Bacillus cereus R5-339. The pH during cornhusk degradation at 28oC ranged from 4.67±0.09 to 7.43±0.16, while the pH at 4oC and 40oC ranged from 4.27±0.06 to 7.45±0.06 and 7.50±0.01 to 4.22±0.06 respectively. The test organism demonstrated the ability to degrade cellulose. Therefore, more research should be carried out if it could give better results when in consortium with other organisms.