Isolation, screening and production of cellulase from Bacteria

Abstract

Cellulase finds uses as raw material in various industries. The current sources of cellulase are highly expensive. However, using bacteria as cellulase producers can bring the cost down and make our industries self-sufficient. This experiment was carried out bearing this thought in mind. The experiment was started by culturing microorganisms obtained from various soil and municipal samples on carboxymethylcellulose agar media. Colonies that showed clear zones after being flooded with Gram's Iodine were further analysed to investigate their ability to utilize filter paper as a carbon source. Postive samples were selected for enzyme production. Biochemical analysis was used to characterize the bacterial isolates. The results indicated a possibility of the isolates being Pseudomonas fluorescens biovar and Streptococcus sp. Bacteria were cultured in carboxymethylcellulose broth. The cultured broth was then centrifuged and the supernatant was used as crude enzyme. The enzyme activity was tested using DNS assay to check glucose liberation after the degradation of cellulosic bonds.. Protein concentration was estimated to be 0.09 mg/mL after performing Biuret’s Assay. Enzyme production was then optimized using a range of temperature, time, pH and carbon source. Cellulase produced from the synergistic effect of the obtained microorganisms was found to be almost five times more potent than the enzymes produced by them separately. The enzyme activity was noted as 0.175 U/mL, whereas, the specific enzyme activity was found to be 1.82 U/mL. Thus, there was a tenfold increase in the value which indicates that the enzyme activity would be increased at least ten times upon concentration and purification of the enzyme.