Efficient Biocatalytic Production of Cyclodextrins by Combined Action of Amylosucrase and Cyclodextrin Glucanotransferase

A novel enzymatic process for cyclodextrin (CD) production was developed by utilizing sucrose as raw material instead of corn starch. Cyclodextrin glucanotransferase (CGTase) from Bacillus macerans was applied to produce the CDs from linear α-(1,4)-glucans, which were obtained by Neisseria polysaccharea amylosucrase (NpAS) treatment on sucrose. The greatest CD yield (21.1%, w/w) was achieved from a one-pot dual enzyme reaction at 40 °C for 24 h. The maximum level of CD production (15.1 mg/mL) was achieved with 0.5 M sucrose in a simultaneous mode of dual enzyme reaction, whereas the reaction with 0.1 M sucrose was the most efficient with regard to conversion yield. Consequently, dual enzyme synthesis of CDs was successfully carried out with no need of starch material. This result can be applied as a novel efficient bioconversion process that does not require the high temperature necessary for starch liquefaction by thermostable α-amylase in conventional industrial processing.