WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
Browse
2 results
Search Results
Now showing 1 - 2 of 2
Conference Object Citation - WoS: 1Optimization of Exo-Polygalacturonase Production From Orange Peel by Aspergillus Sojae(Elsevier, 2010) Büyükkileci, Ali Oğuz; Tarı, Canan; Fernandez-Lahore, H. M.; Gençkal Demir, Hande; Göğüş, NihanPectinases catalyze the degradation of pectic substances, thus they are used extensively in fruit juice and wine industry to facil-itate extraction and clarification. Aspergillus species, in particular Aspergillus niger, have long been utilized for production of pectinases. Previous studies of our group showed that A. sojae has a potential to produce enhanced amount of polygalacturonase, which is one of the pectic enzymes, in both submerged and solid-state cultures (Gogus et al., 2006; Tari et al., 2007). In this study, several agricultural products were screened in an effort to find a cheap and abundant substrate for submerged polygalacturonase production using a UV-mutated A. sojae strain. Medium composition was optimized to further enhance the enzyme level. Experiments were designed and analyzed statistically using the trial version of the statistical software, Design Expert.Article Citation - WoS: 52Citation - Scopus: 62Solid-State Production of Polygalacturonase by Aspergillus Sojae Atcc 20235(Elsevier Ltd., 2007) Üstok, Fatma Işık; Tarı, Canan; Göğüş, NihanThe 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 R2 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 × 107 total spores and 5-6 days. The predicted enzyme activity (30.55 U/g solid) and spore count (2.23 × 107 spore/ml) were very close to the actual values obtained experimentally (29.093 U/g solid and 2.31 × 107 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.