Description

ABSTRACT

Cellulase  is  an  enzyme  complex  which  breaks  down  cellulose  to glucose. It  has  been  used  widely  in commercial  food  processing,  textile  industry  and  laundry  detergents. Majority of studies on cellulase production have focused on fungi, with relatively lesser emphasis on bacterial sources. The current study has focused on isolating bacteria from paddy soil, capable of producing free cellulase and optimization of culture media for increasing cellulase production. Cellulase producing bacteria was isolated from paddy soil and was identified using 16S rDNA sequencing and BLAST search. Screening of nutrients and their influence on the cellulase production was studied using a Plackett-Burman design. Five variables (NH₄)₂SO₄, Cellulose, K₂HPO₄, CaCl₂.2H₂0, pH were screened to evaluate their effect on cellulase production, of only two variable K₂HPO₄ andcellulose were found to have significant effect on cellulase production. Two components with significant effect on cellulase production were further optimized with Response Surface Methodology (RSM) using Central Composite Design (CCD).The optimal levels of these medium components determined were K₂HPO₄ (2g/ml) andCellulose (2g/ml). The enzyme activity with nutritional medium was 0.148 U/ mL, but a 2 fold increase in the cellulase activity in optimized medium was observed.

Keywords: Cellulase, Central Composite Design, Optimization, Plackett-Burman design, Response Surface Methodology, 16S rDNA sequencing.