Effect of different substrates and their preliminary treatment on cyclodextrin production

Various kinds of substrates were tested for cyclodextrin production with cyclodextrin glucanotransferase (CGTase) from Bacillus megaterium. The enzyme formed cyclodextrin from different kinds of starch, dextrins, amylose, and amylopectin. However, the highest degree of conversion was obtained from starch. Corn starch appeared to be the best substrate - the cyclodextrin yield was 50.9%. The effect of molecular mass and preliminary treatment of starch with alpha-amylase on the CD yield was investigated. It was proved that CGTase preferred native starch with high molecular mass and low dextrose equivalent. The preliminary treatment with alpha-amylase occurred to be inefficient and unnecessary since it did not lead to an increase in the CD yield. Some of the substrates were treated with pullulanase. The effect of debranching was highest in the case of corn starch: the cyclodextrin yield increased by 10%.