The production of beta-maltooligosaccharides of glycitein and daidzein using Lactobacillus delbrueckii and cyclodextrin glucanotransferase (CGTase) as biocatalysts was investigated. The cells of L. delbrueckii glucosylated glycitein and daidzein to give their corresponding 4'- and 7-O-beta-glucosides. The beta-glucosides of glycitein and daidzein were converted into the corresponding beta-maltooligosides by CGTase. The 7-O-beta-glucosides of glycitein and daidzein and 7-O-beta-maltoside of glycitein showed inhibitory effects on IgE antibody production. On the other hand, beta-glucosides of glycitein and daidzein exerted 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging activity and supeoxide-radical scavenging activity.