Indigestible dextrin is an excellent inducer for α-amylase, α-glucosidase and glucoamylase production in a submerged culture of Aspergillus oryzae

α-Amylase activities of Aspergillus oryzae grown on dextrin or indigestible dextrin were 7·8 and 27·7 U ml−1, respectively. Glucoamylase activities of the cultures grown on dextrin or indigestible dextrin were 5·4 and 301 mU ml−1, respectively. The specific glucoamylase production rate in indigestible dextrin batch culture reached 1·35 U g DW−1 h−1. In contrast, biomass concentration of A. oryzae in indigestible dextrin culture was 35% of that in dextrin culture. Thus, the culture method using indigestible dextrin has the potential to improve amylolytic enzyme production and fungal fermentation broth rheology.