Isolation, screening, and cellulase assay of cellulolytic bacteria from rice field soil

Abstract

This study is focused on the isolation and screening the cellulolytic bacteria and assessing the potential of the cellulose degradation efficiency. The rice field soil from Ang Thong province collected and screened the active cellulolytic bacteria by Gram’s iodine staining. This rice field use the plowing the rice straw with the soil instead of burning to prepare the next harvesting. From the experiment, 37 of 80 isolates were defined as a cellulolytic bacterium by the Gram’s iodine staining test. The Hydrolysis Capacity (HC) estimation and statistical analysis showed that 9 isolates had a highest HC value and selected for cellulase assay and biodegradation efficiency test. They were named as following; CB4, CB12, CB27, CB30, CB36, CB40, CB42, CB47, and CB71. Colony morphology study can be confirmed that the isolated CB36 is bacteria and obtained the most HC value, can be concluded that active cellulolytic bacteria can be isolated from the rice field. Due to the Covid-19 situation, the cellulase assay and biodegradation test could not be done because the university was close. This study, therefore, has shown the isolation and screening of cellulolytic bacteria from the unburnt rice field soil and used for rice straw management in the future to reduce the pollutant emission from rice straw burning activity.