Bacterial strain isolated from the Mango field and identified on the basis of 16S rDNA sequence information and optimization of the alkaline cellulase production

Abstract

A bacterial strain was isolated from the soil of mango (Mangifera indica) orchards. The isolate was identified as Paenibacillus ahvei [MTCC 7809] through phylogenetic analysis based on the 16S rDNA gene sequencing and also by conventional biochemical processes. The scanning electron microscopic analysis revealed the morphological details of the strain. The isolate is Gram positive. motile, rod shaped, spore forming bacterium with extreme salt tolerance. It can hydrolyze starch and gelatin, and catalase and oxidase were produced. The cellulase activity of the culture broth was determined by measuring the reducing sugar released from carboxymethyl cellulose (CMC). Different cultural conditions were tested to reach the optimum growth conditions in order to obtain large-scale production of alkaline cellulase for commercial importance. Crude cellulase from Paenibacillus alvei (MTCC 7809) showed activity and stability at moderately high temperature and pH and the activity remained stable at 40°C and pH 8 after 2h of incubation making the strain a good choice for industrial applications. The rDNA sequence of 1509bp is submitted into the NCBI GenBank database (Acession no. EF429201).