Biosynthesis of ascorbic acid

Conklin, PL., 2001, Recent advances in the role and biosynthesis of ascorbic acid in plants. Plant Cell Environ. 24 383-394. 

Smirnoff, N., Conklin, P.L., and Loewus, F.A., 2001, Biosynthesis of ascorbic acid in plants A renaissance. Anna. Rev. Plant Physiol. Plant Mol. Biol. 52 437 167. 

These generalizations are illustrated by the recent synthesis of L-ascorbic acid glucosides 11 and 12 (16), The monosodium salt of ascorbic acid in N,N-dimethylformamide (DMF) affords exclusively the 03 monoalkylated derivative 9 on alkylation with 2,3,4,6-tetra-O-a-n-glucopyranosyl bromide. To obtain the 02 glucosylated derivative 10, under the same conditions, required the protection of the C3 hydroxyl as a methyl ether. Several workers have reported the biosynthesis of ascorbic acid glucosides in bacteria (17) however, the structure and position of glucosylation in these compounds has not been unambiguously determined. 

The existence of several excellent reviews and treatises on ascorbic acid has made unnecessary the detailed treatment of the older references. The historical aspect of much of our present knowledge on ascorbic acid was discussed in a symposium (L15) on the bicentenary of publication of James Lind s Treatise of the Scurvy (L14). In the same year, two other useful reviews were published. Meikeljohn (M18) gave a critical evaluation of the effects of vitamin C on physiology, dealing as he did with different problems related to the field of medicine. More detailed information, less critically evaluated, was presented by Lloyd and Sinclair (L19). The most systematic and comprehensive appraisal of ascorbic acid in all its aspects represents the contributions by a number of workers in the field, compiled in The Vitamins, (S14). The recent advances in knowledge of biosynthesis of ascorbic acid have been described by Burns (B38) and Burns and AshweU (B39). There was a recent symposium on ascorbic acid with contributions from many workers (K6). 

The possibility that the biosynthesis of ascorbic acid occurred through sorbose and 2-keto-L-gulonic acid, as in the chemical synthesis, was eliminated when the latter was not converted to ascorbic acid, and L-sorbose-6-C gave rise to ascorbic acid labeled in both carbons 1 and 6. Sorbose was evidently degraded and converted to glucose before being transformed into ascorbic acid. 

Carton MFX (1965) Reaction allergique au cours d un traitement vitamine Kj H- extrait de foi. Bull Soc Fr Dermatol Syphilol 72 228 Chanarin I, Fenton JCB, Mollin DL (1957) Sensitivity to folic acid. Br Med J 1 1162-1163 Chatterjee IB (1973) Evolution and the biosynthesis of ascorbic acid. Science 182 1271-1272 Chick H (1975) The discovery of vitamins. Prog Food Nutr Sci 1 1-20 Conrad DH, Wirtz GH (1973) Characterization of antibodies to vitamin A. Immuno-chemistry 10 273-275... 

Biosynthesis of ascorbic acid and its conversion into dehydroascorbic acid. See Oxalic acid (Fig. 2.). 

It was also postulated that ascorbic acid and L-xylose have a common intermediate—namely, 3-keto-L-gulonic acid. Although the compound has definitely been established to be an intermediate for L-xylose, it is not likely to be involved in the biosynthesis of ascorbic acid. 

Chatterjee, I. B., 1973a, Evolution and the biosynthesis of ascorbic acid. Science 182 1271-1272. 

INDUCED HISTAMINE FORMATION AND BIOSYNTHESIS OF ASCORBIC ACID IN THE RAT... 

Otsuka et al. (1986) used TLC to isolate and partially characterize degradation products of 2,3-diketo-L-gulonic acid (intermediates in the biosynthesis of ascorbic acid) the products were characterized by different spectrometric methods. Mandrou et al. (1988) devised a TLC procedure to determine ascorbic and dehydroascorbic acids in fruit juices and wine the sample was reacted with 2,4-dinitrophenylhydrazine to form the osazones the osazones were spotted on the TLC plate and quantified by. in situ densitometry at 494 nm. 

The biosynthesis of ascorbic acid in plant tissues has been shown to be influenced by a number of factors, the most prominent of which is light. The relationship of vitamin C and light had become the subject of research even before the vitamin had been isolated and chemically identified. As research progressed, it became evident that light had a profound infiuence on the ascorbic acid content of green plants, and that it was the chief environmental factor concerned. 

Some of the most recent work which has been recorded in this review has thrown new light upon the problem of the biosynthesis of ascorbic acid. Until recently the pathway whereby ascorbic acid is formed from sugars was one of almost complete speculation. Now, with knowledge of some of the possible intermediates and with the demonstration of the i thesis of ascorbic acid by enzymes in vitro, it would seem that new... 

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