Multielement Determination in Medicinal Plants and Herbal Medicines Containing Cynara scolymus L., Harpagophytum procumbens D.C., and Maytenus ilifolia (Mart.) ex Reiss from Brazil Using ICP OES

Worldwide, medicinal plants and herbal medicines are widely consumed. The aim of this study was to determine macro- (Ca, K, Mg, Na, and P) and microelements (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, Si, Sn, Sr, V, and Zn) in medicinal plants and herbal medicines: “globe artichoke” - Cynara scolymus L., “devil’s claw” - Harpagophytum procumbens D.C., and “espinheira santa” - Maytenus ilifolia (Mart) ex Reiss. Concentrations of 24 (essential and toxic potentially) elements in samples from Brazil were determined using a sequential optical emission spectrometer with inductively coupled plasma optical emission spectrometry (ICP OES) after acid digestion, assisted by microwave radiation. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to carry out an exploratory analysis of samples. The elements were quantified (in μg/g): Al (20.24–1261.64), Ba (18.90–63.18), Ca (2877.6–19,957.40), Cr (0.28–1.38), Cu (4.16–21.99), Fe (8.54–627.49), K (1786.12–32,297.19), Mg (505.82–6174.52), Mn (0.40–205.64), Na (1717.23–18,596.45), Ni (< LoQ–0.99), P (35.12–2899.91), Se (1.52–3.71), Sn (1.53–12.43), Sr (52.33–84.31), V (< LoQ–0.24), and Zn (2.60–30.56). As, Cd, Co, Mo, Pb, and Sb, in all the investigated samples, were found to be below the limit of detection (LoD) and quantification (LoQ) values of ICP OES. These medicinal plants and herbal medicines can be sources of Ca, K, Mg, Na, P, Cu, Fe, Mn, Se, and Zn. All samples showed considerable levels of Al. PCA and HCA showed that the samples separated into two large groups.