Evaluation of cellulases and xylanases production from bacillus spp. isolated from buffalo digestive system

Abstract

Cellulases and xylanases have high industrial demand due to their paramount importance in biological processes. The present study was aimed to evaluate the fiber degrading potential of Bacillus spp. isolated from buffalo digestive system. A total of fourteen isolates from rumen and eight isolates from dung were screened on carboxymethyl cellulose (CMC; 1%) agar plates, showing clear zone of CMC hydrolysis. All screened isolates were confirmed by targeting the 16S rRNA gene, sequencing and phylogenetic analysis. The enzyme activity index (EAI) of all screened isolates was calculated and it was observed that BR28 (Bacillus subtilis), BR96 (Bacillus amyloliquefaciens), BD69 (Bacillus tequilensis) and BD92 (Bacillus sonorensis) exhibit 2.11, 2.05, 2.56 and 2.45 EAI, respectively. The isolates with high EAI (>2) were selected for further enzyme production studies. The results of enzyme activities showed that BD92 had higher endoglucanse (carboxymethyl-cellulase, CMCase, 240.76±4.12 U/L) and avicelase (153.56±7.28 U/L) activities after 72 h of incubation. However, BR96 showed highest xylanase (3379.27±10.58 U/L) activity than others isolates and previously reported studies. This study provides a helpful insight into the identification of Bacillus spp. from the buffalo digestive system with higher production of cellulases and xylanases for their application in the animal feed industry.

Keywords

• cellulase
• xylanase
• bacillus spp.
• phylogenetic analysis
• buffalo digestive system