Enzymatic Synthesis of Clucosyl Rebaudioside A and its Characterization as a Sweetener

摘要

Rebaudioside A was modified via glucosylation by recombinant dextransucrase of Leuconostoc lactis EG001 in Escherichia coli BL21 (DE3), forming single O-α-D-glucosyl-(1"→6') rebaudioside A with yield of 86%. O-α-D-glucosyl-(1"→6') rebaudioside A was purified using HPLC and Diaion HP-20 and its properties were characterized for possible use as a food ingredient. Almost 98% of O-α-D-glucosyl-(1"→6') rebaudioside A was dissolved after 15 days of storage at room temperature, compared to only 11% for rebaudioside A. Compared to rebaudioside A, O-α-D-glucosyl-(1"→6') rebaudioside A showed similar or improved acidic or thermal stability in commercial drinks. Thus, 0-α-D-glucosyl-(1"→6') rebaudioside A could be used as a highly pure and improved sweetener with high stability in commercial drinks.