Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7585109 | Food Chemistry | 2018 | 27 Pages |
Abstract
Steviol glycosides from Stevia rebaudiana leaves are used in stevia-based sweeteners for their intense sweetness and low calories. Rebaudioside D is present in leaves in minute quantities (â¼0.4-0.5% w/w total dry weight), but it is â¼350 times sweeter than sucrose, and sweeter than the more abundant rebaudioside A and stevioside. In the present study, pathways for rebaudioside D synthesis and UDP-glucose recycling were developed by coupling recombinant UDP-glucosyltransferase UGTSL2 from Solanum lycopersicum and sucrose synthase StSUS1 from Solanum tuberosum. Reaction parameters, including substrate ratio, sucrose concentration, temperature, crude extract concentration, and reaction time, were evaluated, and 17.4â¯g/l of rebaudioside D (yieldâ¯=â¯74.6%) was obtained from 20â¯g/l of rebaudioside A after 20â¯h, using UDP or UDP-glucose in recombinant cell crude extracts. Extending the reaction time generated rebaudioside M2 from further glycosylation of rebaudioside D. Km values for UGTSL2 indicated a higher affinity for rebaudioside D than for rebaudioside A.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Liangliang Chen, Ping Sun, Fangfang Zhou, Yan Li, Kequan Chen, Honghua Jia, Ming Yan, Dachun Gong, Pingkai Ouyang,