2.3.3. Solid-State Fermentation (SSF): Inoculum Preparation

Two different types of inocula were used: the first consisted of 1 mL of spore suspension (S) obtained by spraying 10 mL of sterile 0.1% Tween-80 solution on 7-day-old PDA Petri dishes containing *A. oryzae*. One milliliter of spore suspension was used to inoculate 50 mL Erlenmeyer flasks containing 1 g of rice hulls. The number of spores was quantified by carrying out serial dilutions and seeding 0.1 mL of each one on the PDA plate. Petri dishes were incubated for 4 days at 28 ◦C and then counted to establish the starting load.

The second type of inoculum consists of the supernatant of submerged liquid fermentation (SLF) and was obtained as follows: 6-day-old Petri dishes grown in PDA medium supplemented with chloramphenicol were used to inoculate a 50 mL Erlenmeyer flask containing 20 mL of PDB medium. After 4 days of growth, 1 mL of the medium was directly added to the rice hulls. The count of starting colonies was made following the same protocol used for spore suspension.
