The fungus exhibited an array of distinctive morphological patterns corresponding to
different pH of BW (Fig. 2b). Mycelium clumps, suspended mycelium and pellets, the
common morphological forms of fungus, were manifested as a response to the variations in
the pH values. However, the pellet types were not the same in their shape and size. Hairy and
less aggregated pellets were dominantly formed at pH 5. The pattern changed into solid and
nonaggregated type at pH 6. While reaching pH 7, formation of even more aggregated pellets
was favored. The clump and suspended mycelium were formed at pH 4 and 8, respectively.
The highest pH (9) value applied did not support the growth of R. oryzae in the fermentation
medium although the incubation was continued for 120 h.