Isolation, Screening and Optimized Production of Extracellular Xylanase under Submerged Condition from Aspergillus Flavus Mtcc 9390

Bharat Bhushan Ajay Pal

doi:10.4172/2329-6674.1000103

Abstract

In order to isolate xylanolytic microbial strains, screening and isolation was done using agricultural waste and decaying biomass. The enzyme super-secreter Aspergillus flavus MTCC 9390 was selected for optimized production of xylanase. Various process variables were optimized using conventional ‘one-variable-at-a-time’ approach which involves varying a single independent variable and maintaining others at a constant level. All culture conditional variables had profound influence on enzyme production and 15-30% increase was brought by nitrogen source only. A synergistic five-fold increase in xylanase production was achieved when an inoculums size of 2 x 106 spores/ mL was incubated in modified Czapek Dox-A for 6 days at pH 6.0 and temperature 45oC under static conditions in submerged fermentation.

Highlights

The complex heterogenous polysaccharide after cellulose in cereals, hardwood and fruit is xylan
One fungal isolate was selected as the potential producer of xylanase which was identified at the Institute of Microbial Technology (IMTECH), Chandigarh, India as Aspergillus flavus
The selected fungal isolate in the present investigations had been identified at Institute of Microbial Technology (IMTECH), Chandigarh as Aspergillus flavus and was included to their collection at the centre with accession number MTCC 9390

Summary

Introduction

The complex heterogenous polysaccharide after cellulose in cereals, hardwood and fruit is xylan These hemicelluloses interact with pectin polysaccharides and the aromatic polymer lignin, and integrate with the cellulose fibrils, creating a rigid structure which strengthens the cell wall. They form covalent cross-links, which are thought to be involved in limiting cell growth and reducing cell wall biodegradability. Endoxylanases (EC 3.2.1.8) are able to cleave the xylan backbone into smaller oligosaccharides, which can be degraded further to xylose by β-xylosidase (EC 3.2.1.37). Endoxylanases differ in their specificity towards the xylan polymer. Some enzymes cut randomly between unsubstituted xylose residues, whereas the activity of other endoxylanases strongly depends on the substituents on the xylose residues neighboring the attacked residues

Methods

Results

Conclusion