It is obvious that at lower agitation speed, the precultured fungus consisting of mixed morphologies of pellets and
mycelium do not become separated from each other, and their further growth leads to
suspended mycelium which is actually the agglomeration. The hydrodynamic force generated
out of the agitation actually dissipates specific free energy that has a control (proportional
relation with an exponent of −0.25) on the fungal mean hyphal length [24]. Thus, with the
increase of flask shaking speed, dissipation of specific free energy will increase exponentially
and cause shorter hyphal length of loose mycelium which is less protected from the shearing
forces and becomes less active [22]. Moreover, formation of pellets itself is supportive of more
protection against shearing stress and less prone to deactivation. Consequently, more number
of hyphae will be functional and metabolic activity will be higher. Thus, the moderate value
(200) of shaking speed supported the pellet formation of R. oryzae 1526 that resulted in more
production of FA compared with other applied speeds.