Detail of "669-90-9"

Reference

Indirect fermentation of D-isoascorbic acid

Indirect fermentation of D-isoascorbic acid. II. Fermentation conditions for 2-keto-D-gluconic acid-producing strains. Jiang, Mingzhu; Wang, Chonglin; Bai, Zhaoxi; Xu, Hongfa; Han, Ruihuan (Shanxi Inst. Biol., Taiyuan, Peop. Rep. China). Weishengwuxue Tongbao, 11(3), 105-7 (Chinese) 1984. CODEN: WSWPDI. ISSN: 0253-2654. DOCUMENT TYPE: Journal CA Section: 16 (Fermentation and Bioindustrial Chemistry) A precursor of D-isoascorbic acid, 2-keto-D-gluconic acid (I) [669-90-9], was produced by fermn. with Pseudomonas fluorescens K1005 in a basal medium (pH 6.7) contg. corn steep liquor 5, urea 2, KH2PO4 0.6, MgSO4.7H2O 0.25, and CaCO3 2.5 g/L, supplemented with other nutrient sources. The Pseudomonas strain only used glucose and Ca gluconate as C sources for I prodn., whereas all the tested N sources (corn steep liquor, yeast ext., peptone, NH4NO3, and NaNO3) were equally effective. The optimum culture temp. was in the range of 28-30°. For effective I prodn. a seed culture medium (pH 6.7) contg. glucose 1, peptone 1, beef ext. 0.3, yeast ext. 0.3, and MgSO4.7H2O 0.3% and a fermn. medium (pH 6.7) contg. glucose 20, urea 0.158, corn steep liquor 1.8, and CaCO3 6% are recommanded. A sugar conversion rate of 93.1% with I yield of 18.25 g/dL could be obtained when the recommand fermn. medium was used.

Galacturonic, glucuronic, 2- and 5-oxo-gluconic acids in wines, sherries, fruit and dessert wines

Galacturonic, glucuronic, 2- and 5-oxo-gluconic acids in wines, sherries, fruit and dessert wines. Sponholz, W. R.; Dittrich, H. H. (Inst. Mikrobiol. Biochem., Forschungsanst. Weinbau, Gartenbau, Geisenheim D-6222, Fed. Rep. Ger.). Vitis, 23(3), 214-24 (German) 1984. CODEN: VITIAY. ISSN: 0042-7500. DOCUMENT TYPE: Journal CA Section: 16 (Fermentation and Bioindustrial Chemistry) Galacturonic [685-73-4], glucuronic [6556-12-3], 2- [669-90-9], and 5-oxogluconic acids [5287-64-9] were quant. detd. in German wines of different quality, French and Spanish red wines, sherries, and fruit and dessert wines. Galacturonic acid was found in German wines in concns. of 150-1000 mg/L. The diminished amts. of galacturonic acid in high-quality wines may be because of an increase in the galactaric acid content. Red wines contain more galacturonic acid than white wines. In German and Spanish red wines, 500-1100 mg/L of galacturonic acid was detd. Glucuronic acid was found in much lower quantities. Q.b.A. wines to Berrenauslese showed 0-20 mg/L; Trockenbeerenauslese wines and red wines had 5-20 mg/L. 2-Oxogluconic acid occurred in lower-quality wines in quantities of 0-10 mg/L. Most of the Auslese wines contained 0-40 mg/L. Beerenauslese wines normally had 30-150 mg/L. In Trockenbeerenauslese wines, amts. between 0 and 290 mg/L were detd. 5-Oxogluconic acid was found in slightly higher quantities than 2-oxogluconic acid. Sherries showed the same amt. of galacturonic acid as normal German wines. The other oxidized sugar acids were only found in very small amts. Very often the sherries lacked these acids. Fruit and dessert wines showed very low amts. of galacturonic acid. The other acids were absent or only found in trace amts. Apparently, 2-oxo-, 5-oxogluconic, and glucuronic acids are produced by acetic acid bacteria from glucose, and galactaric acid is produced by oxidn. of galacturonic acid.