129499-78-1Relevant articles and documents
L-Ascorbic acid α-glucoside formed by regioselective transglucosylation with rat intestinal and rice seed α-glucosidases: Its improved stability and structure determination
Yamamoto,Muto,Murakami,Suga,Yamaguchi
, p. 3020 - 3023 (1990)
-
Walking a Fine Line with Sucrose Phosphorylase: Efficient Single-Step Biocatalytic Production of l-Ascorbic Acid 2-Glucoside from Sucrose
Gudiminchi, Rama Krishna,Nidetzky, Bernd
, p. 1387 - 1390 (2017)
The 2-O-α-d-glucoside of l-ascorbic acid (AA-2G) is a highly stabilized form of vitamin C, with important industrial applications in cosmetics, food, and pharmaceuticals. AA-2G is currently produced through biocatalytic glucosylation of l-ascorbic acid from starch-derived oligosaccharides. Sucrose would be an ideal substrate for AA-2G synthesis, but it lacks a suitable transglycosidase. We show here that in a narrow pH window (pH 4.8–6.0, with sharp optimum at pH 5.2), sucrose phosphorylases catalyzed the 2-O-α-glucosylation of l-ascorbic acid from sucrose with high efficiency and perfect site-selectivity. Optimized synthesis with the enzyme from Bifidobacterium longum at 40 °C gave a concentrated product (155 g L?1; 460 mm), from which pure AA-2G was readily recovered in ~50 % overall yield, thus providing the basis for advanced production. The peculiar pH dependence is suggested to arise from a “reverse-protonation” mechanism in which the catalytic base Glu232 on the glucosyl–enzyme intermediate must be protonated for attack on the anomeric carbon from the 2-hydroxyl of the ionized l-ascorbate substrate.
METHOD FOR PRODUCING 2-O- ALPHA-D-GLUCOSYL-L-ASCORBIC ACID ANHYDROUS CRYSTAL-CONTAINING POWDER
-
Paragraph 0125; 0126; 0127; 0128, (2013/11/05)
[Object] An object of the present invention is to provide a process for enabling the production of a particulate composition containing anhydrous crystalline ascorbic acid 2-glucoside that significantly, more hardly cakes, even when the production yield of ascorbic acid 2-glucoside does not reach 35% by weight. [Construction] The above object is solved by providing a process for producing a particulate composition containing anhydrous crystalline ascorbic acid 2-glucoside, which comprises allowing a CGTase to act on a solution containing either liquefied starch or dextrin and L-ascorbic acid and then allowing a glucoamylase to act on the resulting solution to obtain a solution with an ascorbic acid 2-glucoside production yield of at least 27%, purifying the obtained solution to increase the ascorbic acid 2-glucoside content to a level of over 86% by weight, precipitating anhydrous crystalline ascorbic acid 2-glucoside by a controlled cooling method or pseudo-controlled cooling method, collecting the precipitated anhydrous crystalline ascorbic acid 2-glucoside, and ageing and drying the collected anhydrous crystalline ascorbic acid 2-glucoside.