Amylase production by Aspergillus spp. in submerged fermentation using malt bagasse residue

The objective of this work was use brewer's malt bagasse residue as an amylase production inducer by Aspergillus spp. (UCP1275, UCP6119, UCP1295, and UCP1261) in submerged fermentation. Initially, production was analyzed in standard culture medium (SCM) containing starch as the only carbon source. Then, the strains were tested for bioconversion potential in a new culture medium containing malt bagasse residue (MBM). A factorial design was applied with the selected strain to define the ideal conditions for cultivation and production, varying the initial pH (5 to 7), temperature (24 to 32ºC), and concentration of malt bagasse residue (5 to 15g/L). According to the results, all strains of Aspergillus spp. tested demonstrated amylolytic activity in a standard medium. In the alternative medium containing malt bagasse (MBM), strain 1 (Aspergillus spp. UCP 1275) was selected for its high potential in the production of amylase (2.264 U/mL). In planning condition 1 (pH 5, temperature 28ºC, and 5g/L of malt bagasse residue), this strain produced 7.59U/mL of amylase. From the data obtained, Aspergillus spp. UCP 1275 proved to be a promising microorganism for amylase production in a sustainable culture medium in submerged fermentation.