Synthesis of 2-O-a-D-glucopyranosyl L-ascorbic acid by cyclomaltodextrin glucanotransferase from bacillus sp.

• Main Author: Abd. Rahman, Roshanida
• Format: Monograph
• Language: English
• Published: Universiti Teknologi Malaysia 2006
• Subjects: TP Chemical technology
• Online Access: http://eprints.utm.my/id/eprint/2794/1/74184.pdf; http://eprints.utm.my/id/eprint/2794/; http://www.tandfonline.com/doi/abs/10.1080/00021369.1991.10870856

Cyclomaltodextrin glucanotransferase (CGTase) [EC 2.4.1.19] was found to catalyze the transglycosylation from α-cyclodextrin (α-CD) to l-ascorbic acid (AA). A main product formed by this reaction was identified as 2-O-α-d-glucopyranosyl l-ascorbic acid (AA-2G) with the enzymatic hydrolysis and ultraviolet absorption spectra using standard AA-2G. A series of maltooligosaccharide substituted 2-O-derivatives of AA were also detected by HPLC. These were thoroughly hydrolized to AA-2G and glucose by treatment with glucoamylase [EC 3.2.1.3]. A large amount of AA-2G was prepared with 500 g of AA and 1000 g of α-CD. Two hundred and fifty grams of purified AA-2G, the content of which was 97%, was obtained through enzyme reactions and purification with HPLC using an ion-exchange resin.