Isocratic chromatography of resveratrol and piceid after previous generation of fluorescent photoproducts: Wine analysis without sample preparation

Abstract

Resveratrol and its 3-glucoside (piceid), are stilbene-like molecules produced by plants. Both of them are weakly fluorescent, but highly fluorescent compounds are obtained when their hydroethanolic solutions are UV-irradiated, which implies a substantial improvement in the sensitivity of analytical methods. Experimental design (central composite design) together with the response surface methodology have been used to find optimum conditions for the fast, sensitive, and precise chromatographic analysis (with isocratic elution) of resveratrol and piceid in wine samples. These compounds have been UV-transformed into their respective photoproducts, which have been separated in a C18 column (Novapack C(18) 150x3.9 mm, 4 microm) by isocratic elution, using a mobile phase made up of acetonitrile and 4.1 vol% aqueous acetic acid, 19:81 v/v, at a flow rate of 0.8 mL/min, and fluorimetrically detected at 364 nm (lambda(exc) = 260 nm). Detection limits (S/N = 3) are 0.29 and 0.28 microg/L for resveratrol and piceid, respectively. The method has been applied to the analysis of these compounds in wine samples without a clean-up step. The analysis is completed in only 20 min. The standard addition method has been applied to the analysis of a commercial red wine and average recoveries near 100% were obtained for resveratrol and piceid. Three wine pools were satisfactorily analysed by external calibration.

Modulation of Photochemical Damage in Normal and Malignant Cells by Naturally Occurring Compounds†

“…2). Following exposure to the Hg vapor arc lamp, a fluorescent derivative, designated fl‐RES, appeared with an excitation peak at 315 nm, and a triphasic emission curve, with peaks at 360, 380 and 405 nm, likely corresponding to the three rings of the tricyclic Fl‐RES, which is the proposed structure of this photoderivative (42). Longer duration light exposures increased the yield of Fl‐RES (Fig.…”

“…(A) From left to right: trans ‐RES (the native form), cis ‐RES (the photoinduced isomer), fl‐RES (a highly fluorescent photoderivative; the structure shown here is that proposed by Galeano‐Diaz et al. [42]) and ursolic acid. (B) The UV absorption spectra of each of the above compounds; from left to right: t‐RES, c‐RES, fl‐RES and ursolic acid.…”

“…Moreover, the photoisomerization of t‐RES to c‐RES is not the only light‐sensitive reaction. Continued exposure of c‐RES to UVA produces an irreversible conversion to a tricyclic, phenanthrene‐like compound, fl‐RES, that is highly fluorescent (42) (Fig. 1A).…”

Development and validation of a liquid chromatography with mass spectrometry method to determine resveratrol and piceid isomers in beeswax

“…The determination of resveratrol and its related compounds has usually been achieved by means of LC in RP mode (C 18 columns) with UV or diode array , fluorescence , or MS detectors . It should be also mentioned that the hyphenation of RP‐LC and zwitterionic hydrophilic interaction LC with MS has been successfully employed in the last years for the analysis of phenols, including cis ‐ and trans ‐resveratrol .…”

Determinación de cis-/trans-Estilbenos (Resveratrol y Piceido), Triptófano y Metabolitos en productos apícolas por cromatografía de líquidos

“…Estas técnicas se han aplicado para la determinación de todos o algunos de los estilbenos de interés en muestras de vino y algunos derivados [52,82,[110][111][112][113][114][115][116][117][118][119][120][121][122][123][124][125][126] , uvas [49,[127][128][129] , fresas [130] , tomate [131] , cervezas [132] , zumos de frutas [133] , pistacho [48] , cacahuetes [47,[134][135] , chocolate y cacao [136] , plantas [137][138][139][140][141] , fluidos biológicos [142][143][144][145][146][147][148] y preparados farmacéuticos [148] , en lo que se refiere a productos derivados de la colmena se han encontrado métodos en los que se analiza resveratrol en propóleos [149] , pero en ningún caso en miel o polen. En lo que se refiere a la SPE, ésta ha sido empleada en muestras acuosas como la cerveza,…”