Gluconobacter fermentation

The sugars in fruits such as grapes are feimented by yeasts to produce wines. In winemaking, lactic acid bacteria convert malic acid into lactic acid in malolactic fermentation in fruits with high acidity. Acetobacter and Gluconobacter oxidise ethanol in wine to acetic acid (vinegar). 

Deoxy-4-fluoro-D-fructose (552) was prepared (59%) by fermentation of 3-deoxy-3-fluoro-D-mannitol with Gluconobacter oxydans. The structure of 552 (fi-T) form) was confirmed by the n.m.r. spectrum, which resembles that of 4-deoxy-4-fluoro-Q -D-sorbopyranose (553) 552 was identical with one of the products obtained from the oxirane-ring opening of 3,4-anhy-dro-l,2-0-isopropylidene- -D-tagatopyranose with KHFj. 

Two different mechanisms for the formation of L-xyZo-2-hexulosonic acid (28) from L-sorbose (25) have been proposed, depending on the organism used for the fermentative oxidation. It was concluded280-283 that the metabolism of 25 by Pseudomonas aeruginosa IFO 3898 most probably follows the sequence 25 — L-idose (41) — L-idonic acid (42) — 28. Both 41 and 42 were isolated from the fermentation broth. With Gluconobacter melanogenus, it was concluded284-287 that 25 is... 

Tkac et al. [16] Ethanol Off-line monitoring of S. cerevisiae batch fermentation Alcohol oxidase (AOx) in Gluconobacter oxydans cells/covered with a cellulose acetate (CA) membrane Glassy carbon electrode/ +300mV vs. SCE Ferricyanide... 

The majority of dextrans in nature are produced extracellularly via dextran-sucrase from sucrose by several lactic acid bacteria, principally Leuconostoc and Streptococcus species [13]. Dextran is also synthesised by dextrinase of different Gluconobacter species [56]. Referring to this enzyme, fermentation of maltodextrins leads to a- —4) branched dextrans with comparatively lower Mw. However, dextransucrase from Leuconostoc mesenteroid.es NRRL B-512F has attracted most interest because of commercial use. 

Acetic acid fermentation Vinegar Grapes, potatoes, various fruits after alcoholic fermentation Acetobacter europeus Acetobacter aceti Acetobacter pasteurianus Acetobacter hansenii Gluconobacter oxydans... 

Gluconobacter oxydans is generally found growing in sugar-rich environments where alcohol is either absent or present in low concentrations. Typical sites of isolation include flower parts and deteriorating fruit. By comparison, Acetobacter spp. are generally isolated from fermented sub-... 

Saito Y, Ishii Y, Hayashi H, Yoshikawa K, Noguchi Y, Yoshida S, Soeda S, Yoshida M (1998) Direct fermentation of 2-keto-L-gulonic acid in recombinant Gluconobacter oxydans. Biotechnol Bioeng 58 309-315... 

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