Pellet morphol. formation by filamentous fungi has gained a lot of attention because of its multiple benefits such as the ease of sepn. and smaller bioreactor vol. requirement. Most reported kinetics studies on fungal pellet growth are centered on aeration, despite the exptl. results pointing to the importance of other factors such as pH, substrates and product concn. etc., influencing the pellet formation. Hence a kinetic study on the effect of multiple factors such as aeration, substrate and product concn. and pH was done in this paper using Neurospora intermedia as a model organism, whose ability to form mycelial pellets was recently reported. The max. growth rate of the pellets under uninhibited conditions at its optimal growth pH was 0.318 h-1. The pellets were found to be inhibited by high product (ethanol) concn. with no growth occurring at 70 g L-1 and above. High substrate concn. favored the formation of loose fur-like fluffy pellets. The specific oxygen uptake rate of the pellets was between 0.27-0.9 mmol-O2 g-biomass-1h-1 depending on the pellet av. diam. The results from this kinetic study can be used for bioreactor design, operations and optimization of fermn. processes utilizing N. intermedia. [on SciFinder(R)]