Synthesis of curcumin β-maltooligosaccharides through biocatalytic glycosylation with Strophanthus gratus cell culture and cyclodextrin glucanotransferase

A two step synthesis of a series of curcumin β-maltooligosaccharides through sequential biocatalytic glycosylation using Strophanthus gratus cell culture and cyclodextrin glucanotransferase (CGTase) is reported. Cultured plant cells of S. gratus converted exogenously added curcumin into unnatural curcumin β-d-glucoside. Furthermore, four unnatural β-maltooligosaccharides, that is, α-Glc-1→(4-α-Glc-1→)n−14-β-d-glucosides (n = 1–4), of curcumin were produced from curcumin β-d-glucoside in the presence of starch by CGTase-catalyzed glycosylation.