Solid-state production of polygalacturonase by Aspergillus sojae ATCC 20235


Ustok F. I., Tari C., GÖĞÜŞ BAĞIŞ N.

JOURNAL OF BIOTECHNOLOGY, vol.127, no.2, pp.322-334, 2007 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 127 Issue: 2
  • Publication Date: 2007
  • Doi Number: 10.1016/j.jbiotec.2006.07.010
  • Journal Name: JOURNAL OF BIOTECHNOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.322-334
  • Keywords: Aspergillus sojae, polygalacturonase, solid-state fermentation, response surface methodology, PECTINASE PRODUCTION, AGROINDUSTRIAL RESIDUES, ALKALINE PROTEASE, FERMENTATION, OPTIMIZATION, NIGER, ENZYMES
  • Dokuz Eylül University Affiliated: No

Abstract

The effect of solid substrates, inoculum and incubation time were studied using response surface methodology (RSM) for the production of polygalacturonase enzyme and spores in solid-state fermentation using Aspergillus sojae ATCC 20235. Two-stage optimization procedure was applied using D-optimal and face-centered central composite design (CCD). Crushed maize was chosen as the solid Substrate, for maximum polygalacturonase enzyme activity based on D-optimal design. Inoculum and incubation time were determined to have significant effect on enzyme activity and total spore (p < 0.01) based on the results of CCD. A second order polynomial regression model was fitted and was found adequate for individual responses. All two models provided an adequate R-2 of 0.9963 (polygalacturonase) and 0.9806 (spores) (p < 0.001). The individual optimum values of inoculum and incubation time for maximum production of the two responses were 2 x 10(7) total spores and 5-6 days. The predicted enzyme activity (30.55 U/g solid) and spore count (2.23 x 10(7) spore/ml) were very close to the actual values obtained experimentally (29.093 U/g solid and 2.31 x 10(7) spore/ml, respectively). The overall optimum region considering the two responses together, overlayed with the individual optima. Solid-state fermentation provided 48% more polygalacturonase activity compared to submerged fermentation under individually optimized conditions. (c) 2006 Elsevier B.V. All rights reserved.