The SSF process for enzyme production was carried out in aerated columns immersed in a water bath at 32ºC for 72 h.
The process was studied using a central composite rotatable design 22, where variables tested were the nitrogen concentration (0.32-0.88 % w/w) and the volume of liquid (60.9-89.1 mL).
The lipase activity was analyzed in enzymatic extracts.
The wheat bran, in the fermentation medium, acted as a carbohydrate source and as an inducer for the lipase production.
the wheat bran, in the fermentation found was 153.4 U/gdm, with a nitrogen concentration of 0.6 % and 89.
1 mL of volume of liquid. The response surface model demonstrated that higher volume of liquid had a positive effect in lipase activity, while nitrogen concentration showed an optimal range (0.4-0.6%).