Corncob-induced endo-1,4-beta-d-xylanase of Aspergillus oryzae MTCC 5154: production and characterization of xylobiose from glucuronoxylan.
Eight different fungi were cultivated in a peptone-yeast extract medium containing 1% oat spelt xylan (OSX) to evaluate endo-1,4-beta-xylanase secretion for xylooligosaccharide (XOS) production. Aspergillus oryzae MTCC 5154, Aspergillus flavus , Aspergillus niger , and Aspergillus ochraceus showed significant titers of endoxylanases, which were further used for the production of XOS from birch wood xylan (BWX). A. oryzae produced 89.5 +/- 1.13% XOS in the hydrolysate at 24 h of reaction. The effect of OSX, BWX, and raw corncob on the induction of endoxylanase in A. oryzae was studied, and the xylanase activity was maximum at 96 h of cultivation in 3% corncob containing medium. XOS produced at 36 h of reaction was 5.87 +/- 0.53 mg/mL (12 +/- 2% xylose, 48 +/- 2.43% xylobiose, and 40 +/- 3.6% higher oligomers) from 1% BWX . HPLC/refractive index detection and ESI/MS analysis of fractions obtained by GPC corresponded to neutral and 4- O-methyl-alpha- d-glucuronic acid substituted acidic oligosaccharides. The major fraction, beta- d-xylopyranosyl-(1-->4)- d-xylanopyranose was characterized using (13)C NMR.
Aachary
Ayyappan Appukuttan
AA
Fermentation Technology and Bioengineering Department, Central Food Technological Research Institute, Mysore, Karnataka, India.
Prapulla
Siddalingaiya Gurudutt
SG
D001236:Aspergillus oryzae / Q000201:enzymology*; D004187:Disaccharides / Q000032:analysis / Q000096:biosynthesis*; D043364:Endo-1,4-beta Xylanases / Q000096:biosynthesis*; D004790:Enzyme Induction / Q000187:drug effects; D005658:Fungi / Q000201:enzymology; D009844:Oligosaccharides / Q000096:biosynthesis; D012639:Seeds / Q000737:chemistry; D014990:Xylans / Q000378:metabolism*; D003313:Zea mays / Q000737:chemistry*
D004187:Disaccharides; D009844:Oligosaccharides; D014990:Xylans; C038910:glucuronoxylan; D043364:Endo-1,4-beta Xylanases; C004173:xylobiose