Abstract
Aspergillus oryzae is known to have remarkable potential for the production of secreted enzymes. Submerged (Smf) and solid-state fermentation (SSF) are optimized with regard to temperature, pH, moisture, fermentation time, inoculum concentration, etc. Besides these parameters, the effect of light on growth and its role as a bioprocess variable in controlling enzyme production in A. oryzae is pivotal and hence the subject of study. A. oryzae was shown to be susceptible to light; growth was affected and the vegetative phase of the fungus was retarded. Biochemical alterations in biomass, growth diameter, chitin, and conidiation were also observed. The acid protease production by Smf and SSF showed improvement when incubated under darkness. Our study demonstrates for the first time that light must be considered as a bioprocess variable, as certain strains of A. oryzae are sensitive to light. Moreover, total darkness could be effectively employed in protease production on a pilot scale.
