Ascorbic Free Radical formation during the oxidation-reduction of the ascorbic acid system has been studied. It is known that AA oxidation is a two-step reaction each step removing one electron. The first oxidation product is a semiquinone-like free radical, i.e. Ascorbic Free Radical (AFR). We have shown that both enzymic and non-enzymic reduction of DHA to AA did not generate AFR. DHA reduction thus seems to proceed by a single-step transfer of two electrons.
Referenze Bibliografiche
[1] S. Lewin (1976) - Vitamin C: Its Molecular Biology and Medical Potential «Academic Press London» (N. Y.), p. 5.
[2] O. Arrigoni, R. Arrigoni-Liso e G. Calabrese (1975)- «Nature», 256, 513-514.
[3] M.J. Cline (1975) - The White Cell, «Harvard Univ. Press», p. 49.
[4] L. Pauling (1974) - «Proc. Natl. Acad. Sci.», 77, 4442-4446.
[5] M. Yamaguchi e M.A. Joslyn (1951) - «Plant Physiol.», 26, 757-772.
[6] O. Arrigoni, S. Dipierro e G. Borraccino (1981) - «FEBS Lett.», 125, 242-244.
[7] S. Lewin (1976) - Vitamin C: Its Molecular Biology and Medical Potential, «Academic Press London», (N.Y.), p. 40.
[8] C. Lagencrantz (1964) - «Acta Chem. Scand.», 18, 562.
[9] I. Yamazaki (1962) - «J. Biol. Chem.», 237, 224-229.
[10] I. Yamazaki e L. Piette (1961) - «Biochim. Biophys. Acta», 50, 62-69.
[11] Z. Dische e H. Zil (1951) - «Am. J. Ophthalmology», 38, 104-113.
[12] A. Nason, W.D. Wosilait e A.J. Terrel (1954) - «Arch. Biochem. Biophys.», 48, 233-235.
[13] G.V. Foerster, W. Weis e H. Staudinger (1965) - «Ann. Chem.», 690, 166-169.
[14] K. Krisch e H. Staudinger (1959) - «Biochem. Zeitsch.», 331, 195-208.
[15] T. Hara e S. Minakami (1969) - «Proc. Symp. on Enzyme Chem. Kanazawa 1968», p. 21.
[16] G.L. Mattock (1965) - «J. Chem. Soc.», 4728-4735.
[17]E. Zuskin, A.J. Lewis e A. Bouhuys (1973) - «J. Allergy Clin. Immunol.», 51, 218-226.
[18] S. Udenfriend, C.T. Clark, J. Axelrod e B.B. Brodie (1954) - «J. Biol. Chem.», 208, 731-739.
[19] D.C. Borg (1965) - «Proc. Natl. Acad. Sci.», 53, 829-836.
[20] W.E. Blumberg, M. Goldstein, E. Lauber e J. Peisach (1965) - «Biochim. Bio phys. Acta», 99, 187-190.
Con il contributo del Ministero per i Beni e le Attività Culturali