Oligosaccharide synthesized by glycosyltransferase activity from Pectinex ultra SP-L enzyme preparation

Abstract

Glycosyltransferase activity of Pectinex ultra SP-L (from Aspergillus aculeatus) commercially available enzyme preparation was studied in mono- and bisubstrate systems using different donors (maltose, lactose, and sucrose) and acceptors (fructose, galactose, glucose, maltose, mannose, xylose, lactose, and sucrose). Oligosaccharides consisting of three monomers were detected in the cases of maltose, sucrose, and lactose as monosubstrates, thus this preparation should contain glucosyl-, fructosyl-, and galactosyl-transferase activity. Generally, yields of oligosaccharides synthesized were higher in bisubstrate systems maltose:sucrose, maltose:lactose, and sucrose:lactose than on monosubstrates. Use of maltose:sucrose bisubstrate resulted new oligosaccharide(s) (fructosyl-maltose or glucosyl-sucrose). The optimal ratio of substrates in the case of maltose:sucrose was determined to be 1:9. Increase of the dry content of the reaction mixture induced the transfer reaction. The highest oligosaccharide content was obtained at 60% (w/v) substrate concentration. In the case of the optimal ratio and dry content, 4.02% (w/v) oligosaccharide (DP3) concentration was achieved. These oligosaccharides may alter prebiotic and biochemical properties in food applications.