STARCH CONVERSION BY AMYLASES FROM AUREOBASIDIUM-PULLULANS

A color variant strain (NRRL Y-12974) of Aureobasidium pullulans produ ced a saccharifying alpha-amylase and two forms of glucoamylase extrac ellularly when grown on starch at 28-degrees-C for 4 days. A sugar syr up containing DP1 (degree of polymerization) and DP2 (3: 1) was made f rom maltodextrin DE (dextrose equivalent) 10 (35%, w/w) at 55-degrees- C and pH 4.5 using the amylase preparation (40 U g-1 DS (dry substance )). The syrup composition was highly dependent upon substrate concentr ation but nearly independent of enzyme dose. Glucose syrup containing 9% glucose was made from maltodextrin DE 10 (35% , w/w) at 65-degrees- C and pH 4.5 using the same enzyme preparation at 100 U g-1 DS. The en zyme preparation (100 U g-1 DS) produced 98-100% glucose from raw corn starch at pH 4.5 and 50-degrees-C.