KOJIC ACID PRODUCTION BY ASPERGILLUS-FLAVUS USING GELATINIZED AND HYDROLYZED SAGO STARCH AS CARBON-SOURCES

Direct conversion of gelatinized saga starch into kojic acid by Asperg illus flavus strain having amylolytic enzymes was carried out at two d ifferent scales of submerged batch fermentation in a 250-mL shake flas k and in a 50-L stirred-tank fermenter. For comparison, fermentations were also carried out using glucose and glucose hydrolyzate from enzym ic hydrolysis of sage starch as carbon sources. During kojic acid ferm entation of starch, starch was first hydrolyzed to glucose by the acti on of alpha-amylase and glucoamylase during active growth phase. The g lucose remaining during the production phase (non-growing phase) was t hen converted to kojic acid. Kojic acid production (23.5 g/L) using 10 0 g/L saga starch in a shake flask was comparable to fermentation of g lucose (31.5 g/L) and glucose hydrolyzate (27.9 g/L) but in the 50-L f ermentor was greatly reduced due to non-optimal aeration conditions. K ojic acid production using glucose was higher in the 50-L fermenter th an in the shake flask.