Abstract
The galactosyl transfer reaction to branched cyclodextrins (CDs) was investigated using lactose as a donor substrate and branched CDs as acceptors by various β-galactosidases. Bacillus circulans β-galactosidase synthesized galactosyl transfer products to branched CDs, of which the galactose residues were linked at side chains of branched CDs, not directly at CD rings. Aspergillus oryzae and Penicillium multicolor β-galactosidases also produced derivatives galactosylated at side chains of branched CDs. The structures of main transgalactosylation products of branched CDs by these β-galactosidases seem to be different from those by B. circulans β-galactosidase, judging from the retention times on high performance liquid chromatography.
