WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
Browse
3 results
Search Results
Article Citation - WoS: 7Citation - Scopus: 7Effect of Process Parameters and Microparticle Addition on Polygalacturonase Activity and Fungal Morphology of Aspergillus Sojae(Springer, 2022) Germeç, Mustafa; Karahalil, Ercan; Yatmaz, Ercan; Tarı, CananIn this study, the effects of process parameters (initial glucose concentrations, inoculation rates, and nitrogen sources including yeast extract, beef extract, and ammonium nitrate instead of peptone) on polygalacturonase production by Aspergillus sojae in the shaking incubator were examined. Subsequently, the effect of talcum microparticles on activity and morphology was investigated. Based on the results, the highest activity and lowest pellet diameter were 41.91 U/mL and 1411.9 µm when initial glucose concentration and inoculation size were 20 g/L and 12% (v/v), respectively. Besides, as inoculation rate increased, maximum specific growth rate and saturation constant decreased from 0.39 to 0.27 day−1 and 21.26 to 3.50 g/L, respectively. It was determined that highest activity and lowest pellet diameter were found as 18.53 U/mL and 2953.0 µm when medium was supplemented with 2.5 g/L yeast extract. It was also found that as yeast extract and beef extract concentrations increased, pellet diameter decreased. Additionally, medium was supplemented with talcum as a microparticle (0–25 g/L), and maximum activity was 26.59 U/mL (pellet diameter was 2756.3 µm) when talcum concentration was 5 g/L. In addition, as talcum concentration increases from 0.1 to 5 g/L, the biomass concentration increased relatively, but the enzyme activity increased significantly. However, although talcum concentration in the medium is increased until 20 g/L, while the biomass concentration increased, the activity decreased. Compared to control fermentation (without talcum), the activity increased ninefold. Polygalacturonase was also partially purified via ultrafiltration with the purification fold of 1.84. Consequently, fungal morphology in submerged fermentation can be controlled by microparticle addition fermentation, and thus the enzyme activity can be increased.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: 33Citation - Scopus: 37Relationship Between Morphology, Rheology and Polygalacturonase Production by Aspergillus Sojae Atcc 20235 in Submerged Cultures(Elsevier Ltd., 2006) Göğüş, Nihan; Tarı, Canan; Öncü, Şelale; Ünlütürk, Sevcan; Tokatlı, FigenA full factorial statistical design, with the factors of, two taxonomically different strains, seven types of seed culture formulations (slants) and two types of fermentation media were used to investigate the effect of these parameters on the morphology and polygalacturonase production. The rheology of the final fermentation medium was analyzed and appropriate mathematical model was applied to calculate suspension viscosity. It was found that most fermentation broths showed non-Newtonian flow behavior. According to statistical analysis, factors of strain types and fermentation media and the interaction between them were found significant on the enzyme activity. The effect of seed culture formulations (slants) were found insignificant at the significance level of 1%. Interaction of slants with strain types and fermentation media were also found insignificant. Considering the morphology of the final culture, Aspergillus sojae with the desired pellet morphology in a complex media, inoculated with a seed culture prepared from molasses resulted in maximum polygalacturonase enzyme activity (0.2 U/ml) and lowest suspension viscosity with a broth rheology close to Newtonian flow behavior.