Kinetic analysis of aspergillus oryzae cultivations on starch

Cultivation of Aspergillus oryzae on starch is described as a combination of two rate processes: Starch hydrolysis and the cellular activities of the fungi including growth, enzyme production and maintenance. Kinetic models are presented to describe growth, enzyme production, starch hydrolysis and uptake of the hydrolysis products. Numerical values of the model parameters indicated that the rate controlling step of A. oryzae growth on starch was not starch hydrolysis, but the substrate uptake process. Glucose was one of the starch hydrolysis products. About 35% of the substrate consumed for biomass synthesis was glucose. Its accumulation in the medium did not cause repression of the starch hydrolysing enzymes. Steady state starch hydrolysis rates increased with initial starch concentration in the medium. Starch hydrolysing enzymes of A. oryzae have extensive industrial uses. This study may help in a more detailed understanding of the kinetic aspects of the production of these enzymes.
Biocatalysis and Biotransformation


Kinetic analyses of the effects of temperature and light intensity on growth, hydrogenm production and organic acid utilization by rhodobacter capsulatus
Sevinç, Pelin; Gündüz, Ufuk; Department of Biotechnology (2010)
Effects of temperature and light intensity on photofermentative hydrogen production by Rhodobacter capsulatus DSM1710 by use of acetic and lactic acids as substrates were studied. Experiments were conducted at 20, 30 and 38oC incubator temperatures under light intensities in the 1500 – 7000 lux range. pH of the medium and quantity of hydrogen forming together with quantity of biomass, and concentrations of acetic, lactic, formic, butyric and propionic acids in the medium were determined periodically. Growth...
ABDULLAH, MI; YOUNG, JC; GAMES, DE (American Chemical Society (ACS), 1994-03-01)
Material obtained by the CO2 supercritical fluid extraction (SFE) of the wild and cultivated mushrooms Agaricus silvicola and Agaricus bisporus, respectively, was analyzed by g chromatography (GC)-mass spectrometry and GC-Fourier transform infrared spectrometry. SFE gave results comparable with classical extraction techniques for free fatty acids and esters but with fewer manipulative steps and also resulted in the characterization of acids not previously reported from these sources. The organic acids ident...
Analysis of cellulase and polyphenol oxidase production by southern pine beetle associated fungi
Valiev, Abduvali; Ögel, Zümrüt Begüm; Klepzig, Kier D. (Springer Science and Business Media LLC, 2009-09-01)
In this study, the production of extracellular enzymes by fungi associated with southern pine beetle was investigated for the first time. Cellulase and polyphenol oxidase production were analyzed for three beetle associated fungi. Only the mutualistic symbiont Entomocorticium sp. A was found to produce cellulases and polyphenol oxidase. In time course analyses of cellulase production in batch cultures, Entomocorticium sp. A showed maximum activity of 0.109 U/ml and 0.141 U/ml for total cellulase and endoglu...
BOZOGLU, F; OZILGEN, M; BAKIR, U (Elsevier BV, 1987-09-01)
Survival kinetics of lactic acid starter cultures were modeled considering the microorganism and external medium interfacial area as the critical factors determining the resistance of the microorganisms to freeze-drying. Surviving fraction of the microorganisms increased with the increasing biomass concentration during freeze-drying, and this is attributed to the mutual shielding effect of the microorganisms against the severe conditions of the external medium. Survival of the microorganisms over the storag...
Biochemical and genetic studies on the pyruvate branch point enzymes of rhizopus oryzae
Açar, Şeyda; Hamamcı, Haluk; Department of Biotechnology (2004)
Rhizopus oryzae is a filamentous fungi which produces lactic acid and ethanol in fermentations. R. oryzae has numerous advantages for use industrial production of L-(+)-lactic acid but the yield of lactic acid produced on the basis of carbon consumed is low. Metabolic flux analysis of R. oryzae has shown that most of the pyruvate produced at the end of the glycolysis is channelled to ethanol, acetyl-CoA and oxaloacetate production. This study aimed to answer some questions addressed on the regulation of pyr...
Citation Formats
A. Bayındırlı and S. UNGAN, “Kinetic analysis of aspergillus oryzae cultivations on starch,” Biocatalysis and Biotransformation, pp. 71–78, 1991, Accessed: 00, 2020. [Online]. Available: