High performance liquid chromatography with diode array detection (HPLC -DAD) was used to study the autoxidation of gallic acid in alkaline aqueous solutions and the influence of Mg(II) ion on this process. At pH 10, one main autoxidation product was determined, and based on the data obtained in this study its structure was proposed to some kind of gallic acid dimer. Among the minor products, the compound with characteristics similar to ellagic acid was detected. Chromatographic analysis of gallic acid autoxidation at pH 8.5 in the presence of Mg(II) ion indicated that reaction rate decreased. At the same time the mechanism of reaction(s) also changed, which was indicated by the formation of different autoxidation products. These findings may provide better insight into various actions of gallic acid in biological systems since Mg(II) ions are ubiquitous in all living cells.
Niemetz R, Gross GG. Enzymology of gallotannin and ellagitannin biosynthesis. Phytochemistry. 2005;66:2001–11.
2.
Polewski K, Kniat S, Slawinska D. Gallic acid, a natu ral antioxidant, in aqueous and micellar environment: spectroscopic studies. Curr Top Biophys. 2002;26:217–27.
3.
Kim YJ. Antimelanogenic and antioxidant properties of gallic acid. Biol Pharm Bull. 2007;30:1052–5.
4.
Sakagami H, Satoh K, Hatano T, Yoshida T, Okuda T. Possible role of radical intensity and oxidation poten tial for gallic acid-induced apoptosis. Anticancer Res. 1997;17:377–80.
5.
Serrano A, Papacios C, Roy G, Cespon C, Villar ML, Nocito M, et al. Derivatives of gallic acid induce apoptosis in tumoral cell lines and inhibit lym phocyte proliferation. Arch Biochem Biophys. 1998;350:49–54.
6.
Inoue M, Sakaguchi N, Isuzugawa K, Tani H, Ogihara Y. Role of reactive oxygen species in gallic acid-indu ced apoptosis. Biol Pharm Bull. 2000;23:1153–7.
7.
Sakaguchi N, Inoue M, Ogihara Y. Reactive oxygen species and intracellular Ca2+, common signals for apoptosis induced by gallic acid. Biochem Pharm. 1998;55:1973–81.
8.
Tulyathan V, RB B, Singleton VJ. Oxygen uptake by gallic acid as a model for similar reactions in wines. J Agric Food Chem. 1989;37:844–9.
9.
M F, HS J. Effect of pH on the sta bility of plant phenolic compounds. J Agric Food Chem. 2000;48:2101–10.
10.
Oniki T, Takahama U. Free radicals produced by the oxidation of gallic acid and catechin derivatives. J Wo od Sci. 2004;50:545–7.
11.
Z H, W X. Analysis of phenolic compounds in Chinese olive (Canarium album L.) fruit by RPHPLC DAD-ESI-MS. Food Chem. 2007;105:1307–11.
12.
Gil MI, Tomas-Barberan FA, Hess-Pierce B, Holcroft DM, Kader AA. Antioxidant activity of pomegranate ju ice and its relationship with phenolic composition and processing. J Agric Food Chem. 2000;48:4581–9.
13.
Nikolić GM, Premović PI, Nikolić RS. Spectrophoto metric study of catechol oxidation by areal O2 in alka line aqueous solutions containing Mg(II) ions. Spec trosc Lett. 1998;31:327–33.
14.
Lebedev AV, Ivanova MV, Timoshin AA, Ruuge EK. Effect of group II metal cations on catecholate oxida tion. Chem Phys Chem. 2007;8:1863–9.
15.
Nikolić GM, M VA, Nikolić RS, Mitić SS. Spectroscopic study of Mg(II) ion influence on the autoxidation of gallic acid in weakly alkaline aqueous solutions. Russ J Physi Chem A. 2011;85:2270–3.
The statements, opinions and data contained in the journal are solely those of the individual authors and contributors and not of the publisher and the editor(s). We stay neutral with regard to jurisdictional claims in published maps and institutional affiliations.
