%0 Journal Article
%T Determination of Flavonoids, Phenolic Acids, and Xanthines in Mate Tea (Ilex paraguariensis St.-Hil.)
%A Mirza Boji£¿
%A Vicente Simon Haas
%A Darija £¿ari£¿
%A £¿eljan Male£¿
%J Journal of Analytical Methods in Chemistry
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/658596
%X Raw material, different formulations of foods, and dietary supplements of mate demands control of the content of bioactive substances for which high performance thin layer chromatography (TLC), described here, presents simple and rapid approach for detections as well as quantification. Using TLC densitometry, the following bioactive compounds were identified and quantified: chlorogenic acid (2.1£¿mg/g), caffeic acid (1.5£¿mg/g), rutin (5.2£¿mg/g), quercetin (2.2£¿mg/g), and kaempferol (4.5£¿mg/g). The results obtained with TLC densitometry for caffeine (5.4£¿mg/g) and theobromine (2.7£¿mg/g) show no statistical difference to the content of total xanthines (7.6£¿mg/g) obtained by UV-Vis spectrophotometry. Thus, TLC remains a technique of choice for simple and rapid analysis of great number of samples as well as a primary screening technique in plant analysis. 1. Introduction Mate tea (Sp. yerba mate, Port. Erva-mate) consists of well cut, dried, aerial parts or leaves of Ilex paraguariensis St.-Hil. (Aquifoliaceae) shrub. It contains methylxanthines, mainly caffeine, phenolic acids, and saponins and is used as everyday substitution for coffee (psycho stimulant, analeptic) in the south of Brazil, North of Argentina, Oriental Paraguay, and Uruguay. Besides beneficial effects on cardiovascular system, it has significant antioxidant capacity and can be used for the management of weight in obesity [1¨C3]. Thin layer chromatography (TLC) often represents first-choice technique for samples of plant origin as results can be easily visualized. This technique has been successfully employed for analysis of flavonoids and phenolic acids in wine, propolis, and different medicinal plants [4]. Several studies comparing TLC and HPLC have shown that there is no statistical difference between these methods, and advantage due to lower cost is given to TLC [5, 6]. Determination of xanthines as the main constituents is time consuming titration [7]. Although flavonoids present ubiquitous class of compounds, Bastos et al. [8] did not find any of the analyzed flavonols in mate tea using HPLC technique. Thus, the goal of this work was to identify and quantify polyphenolic and xanthine components of mate densitometrically using HPTLC plates and compare the results obtained with the content of total polyphenols and xanthines based on UV-Vis spectrophotometry. 2. Experimental Section 2.1. Reagents All standards were purchased from Sigma Aldrich (Germany) and organic solutions from Kemika (Croatia). The sample of mate powder (dried aerial parts) was obtained from Santo £¿ngelo, RS, Brazil.
%U http://www.hindawi.com/journals/jamc/2013/658596/