Enzymatic synthesis of kojioligosaccharides using kojibiose phosphorylase

We have attempted to synthesize kojioligosaccharides (oligosaccharides havi ng the alpha -1,2 glycosidic linkage at the nonreducing end) using two meth ods. In the first, mixtures of various proportions of glucose and beta -D-g lucose-1-phosphate (beta -G1P) were allowed to react in the presence of koj ibiose phosphorylase (KPase). In the second, maltose was allowed to react w ith KPase and maltose phosphorylase (MPase) simultaneously. In the former m ethod, kojioligosaccharides having only the alpha -1,2 glucosidic linkage w ere synthesized and the average degree of polymerization (D.P.) of oligosac charides increased with decreasing proportions of glucose. In the second me thod, kojioligosaccharides were obtained at approximately 70% yields under optimum conditions. 4-alpha -D-Kojibiosyl-glucose, kojitriose and kojitetra ose, the principal kojioligosaccharides synthesized, were not hydrolyzed by salivary amylase, artificial gastric juice, pancreatic amylase, or small i ntestinal enzymes.