Production of xylan degrading endo-1, 4-β-xylanase from thermophilic Geobacillus stearothermophilus KIBGE-IB29

Abstract

Xylan degrading bacterial strain was isolated from soil and identified as Geobacillus stearothermophilus KIBGE-IB29 on the basis of morphological, biochemical and 16S rDNA sequence analysis. Optimization of medium and culture conditions in submerged fermentation was investigated for maximum endo-1, 4-β-xylanase production. High yield of xylan degrading endo-1, 4-β-xylanase was achieved at 60 °C and pH-6.0 with 24 h of fermentation. Maximum enzyme was produced using 0.5% xylan as a carbon source, 0.5% peptone, 0.2% yeast extract and 0.1% meat extract as nitrogen sources. Di-potassium hydrogen phosphate (0.25%), calcium chloride (0.01%), potassium hydrogen phosphate (0.05%) and ammonium sulfate (0.05%) were also incorporated in the fermentation medium to enhance the enzyme production. Keywords: Geobacillus stearothermophilus, β-1, 4-D-xylan-xylanohydrolase, Xylanase, Biodegradation, Xyla