Modeling the exponential growth of filamentous fungi during batch cultivation

Abstract

In certain conditions, filamentous fungi are observed to grow exponentially during batch submerged growth. It is shown for three cases, with simple mechanistic models, that an exponential growth assumption is reasonable. The basis of these models is the identification of a growth unit, and a mechanism for its doubling with a constant generation time. The importance of the variation of morphological properties within populations is demonstrated by the comparison of computer simulations of simplified models using average values and either experimental data or computer simulations of detailed stochastic models. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 60: 169–179, 1998.

Two‐Stage Culture Process for Improved Production of Ganoderic Acid by Liquid Fermentation of Higher Fungus Ganoderma lucidum

“…After the pellets reach a large size, the pellet number increase may be due to the pellet breakup. A similar phenomenon was also claimed in filamentous fungi fermentations (8).…”

Enhanced chitosan production and modeling hyphal growth of Mucor rouxii interpreting the dependence of chitosan yields on processing and cultivation time

“…Nielsen and Lejeune have developed models describing hyphal growth based on the relationships among hyphal length, branching and fragmentation due to the shear stress imparted by mechanical mixing of the hyphal growth. The models and their underlying assumptions are described in detail in 29 and 30, and they were applied here to make qualitative assessments of the relationship between chitosan content and hyphal resistance to shear stress. The models express the concentration of hyphal elements per litre e , the total average length of a hyphal element l t , av , the average number of tips n t , av , the tip extension rate q tip , the branching frequency q bran and the fragmentation rate q frag as functions of the power input from the stirrer.…”

Optimization of Soluble Organic Selenium Accumulation during Fermentation of Flammulina velutipes Mycelia

“…Exponential feeding is a simple method that allows cells to grow at a constant growth rate (Kim et al, 2004), and exponential feeding of substrates has been widely applied during fermentation (Ding and Tan, 2006;Miguel et al, 2007;Chen et al, 2009). However, no constant specifi c growth rate of fi lamentous fungi can be assumed, when growth takes place in the form of pellets (Lejeune and Baron, 1998). Therefore, exponential feeding of Se is not applicable during the fermentation of F. velutipes mycelia.…”