Effect of low oxygen concentrations on growth and alpha-amylase production of Aspergillus oryzae in model solid-state fermentation systems.

Oxygen transfer in the fungal mat is a major concern in solid-state fermentation (SSF). Oxygen supply into the mycelial layers is hampered by diffusion limitation. For aerobic fungi, like Aspergillus oryzae, this oxygen depletion can be a severely limiting factor for growth and metabolite production.

Aspergillus oryzae in solid-state and submerged fermentations. Progress report on a multi-disciplinary project.

We report the progress of a multi-disciplinary research project on solid-state fermentation (SSF) of the filamentous fungus Aspergillus oryzae. The molecular and physiological aspects of the fungus in submerged fermentation (SmF) and SSF are compared and we observe a number of differences correlated with the different growth conditions. First, the aerial hyphae which occur only in SSFs are mainly responsible for oxygen uptake.

Contribution of aerial hyphae of Aspergillus oryzae to respiration in a model solid-state fermentation system.

Oxygen transfer is for two reasons a major concern in scale-up and process control in industrial application of aerobic fungal solid-state fermentation (SSF): 1) heat production is proportional to oxygen uptake and it is well known that heat removal is one of the main problems in scaled-up fermenters, and 2) oxygen supply to the mycelium on the surface of or inside the substrate particles may be hampered by diffusion limitation. This article gives the first experimental evidence that aerial hyphae are important for fungal respiration in SSF. In cultures of A.

Validation of a model for process development and scale-up of packed-bed solid-state bioreactors.

We have validated our previously described model for scale-up of packed-bed solid-state fermenters (Weber et al., 1999) with experiments in an adiabatic 15-dm(3) packed-bed reactor, using the fungi Coniothyrium minitans and Aspergillus oryzae. Effects of temperature on respiration, growth, and sporulation of the biocontrol fungus C.