Abstract In many places of the world, medicinal plants represent the only form of treatment for various diseases. This work aimed to determine and correlate minerals of infusions and leaves of medicinal plants grown in Northeastern Brazil. Principal component and hierarchical cluster analysis and Pearson correlation were performed. The higher content of Na was for Ocimum basilicum L. (94.3 mg/100g) and Datura stramonium L. (91.6 mg/100g). The plants examined had low levels of K in infusions. All samples contain Mg at significant levels. The cluster analysis divided the medicinal plants into three groups, associated with Passiflora edulis, Capraria biflora and Phyllanthus amarus. Ca and Al were the minerals that contributed most to an association between the plants in principal component 1; while K, Na and Mg contributed most in principal component 2. Furthermore, the high percentage of extraction, mainly Ca and Mg, suggests these plants could be used as potential mineral supplements.

Este trabalho avaliou propriedades físico-químicas, teores de proteína e minerais em méis do Ceará, um dos principais exportadores do País. Também foi analisada a importância nutricional com relação aos minerais detectados. As propriedades físico-químicas foram determinadas pelos métodos da AOAC e CAC, o conteúdo de proteína pelo método de Bradford e os minerais por espectrometria de absorção atômica. Todas as análises foram feitas em triplicata. Os níveis dos macrominerais sódio (Na), potássio (K), cálcio (Ca), e magnésio (Mg) variaram de 1,80-47,20, 21,30-1513,30, 14,58-304,82 e 2,48-28,33 mg/kg, respectivamente, e os elementos traços ferro (Fe), cobre (Cu), manganês (Mn), zinco (Zn), selênio (Se), e cromo (Cr) variaram de 0,12-8,76, 0,07-1,29, 0,06-1,96, 0,07-1,85 mg/kg, 0,36 × 10-3-62,00 × 10-3 e 22,50 × 10-3-170,33 × 10-3 µg/kg, respectivamente. A amostra de Myracrodruon urundeuva apresentou altos teores dos principais minerais (Na, K, Ca, e Mg). O teor de proteínas para o mel de Anacardium occidentale foi o maior (1121,00 µg/g) entre as amostras de méis analisadas. Entre os minerais, detectados, K apresentou a maior concentração seguido por Ca, Na, e Mg. A pesquisa de elementos traços pode indicar contaminação ambiental. As amostras de méis estudadas apresentaram-se livres de contaminação por elementos traço, excetuando-se quanto ao Mn, em que apenas a amostra proveniente de Piptadenia moniliformis apresentou-se dentro da legislação. As variações dos constituintes químicos devem-se provavelmente às variadas origens florais e os teores de proteínas e minerais ratificam a importância nutricional dos méis do Ceará.

This study evaluated the physicochemical properties and protein and mineral content of honey samples from Ceará State, Northeastern Brazil, one of the major honey exporters in the country. Nutritional importance of the minerals detected was also analyzed. Physicochemical properties were examined according to the AOAC and CAC official methods; the protein content was determined using the Bradford method, and the minerals were analyzed by atomic absorption spectrometry. All analyses were performed in triplicate. The levels of macrominerals sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg) varied from 1.80-47.20, 21.30-1513.30, 14.58-304.82, and 2.48-28.33 mg/kg, respectively, and the trace elements iron (Fe), copper (Cu), manganese (Mn), zinc (Zn), selenium (Se), and chromium (Cr) varied from 0.12-8.76, 0.07-1.29, 0.06-1.96, 0.07-1.85 mg/kg, 0.36 × 10-3-62.00 × 10-3 and 22.50 × 10-3-170.33 × 10-3 µg/kg, respectively. Myracrodruon urundeuva honey sample had high contents of macrominerals (Na, K, Ca, and Mg). Protein content of the Anacardium occidentale honey sample was the highest (1121.00 µg/g) among the samples analyzed. Among the minerals detected in the honey samples, K showed the highest concentration, followed by Ca, Na, and Mg. The presence of trace elements can show environmental contamination. The honey samples studied were free of trace elements contamination, except for Mn; the Piptadenia moniliformis was the only honey sample that was in compliance with the law requirements. The variations of the chemical constituents in the honey samples are probably related to differences in the floral origin and mineral and protein contents and confirm the nutritional importance of Ceará State honey.

O uso de vegetais tem-se difundido largamente nos últimos anos para fins alimentícios, medicinais e cosméticos. Devido à importância do estudo da composição inorgânica desses vegetais, o presente trabalho se propõe a analisar a ocorrência de minerais com comprovadas funções no metabolismo humano em dez ervas de popular uso terapêutico. As amostras estudadas foram tratadas por dois métodos distintos: calcinação seguida de tratamento ácido ou infusão para a obtenção dos chás. Posteriormente, os metais foram determinados quantitativamente utilizando-se espectrofotometria de absorção atômica (Ca, Mg, Mn e Zn), espectrofotometria de absorção molecular (Al e Fe) e fotometria de chama (K e Na). Comparando-se os resultados encontrados no presente trabalho com os valores diários recomendados pela RDA e WHO, sugere-se estudos para a utilização de Chenopodium ambrosioides L. como uma fonte alternativa complementar de Na, K, Mg e Zn, e do Ageratum conyzoides L. como fonte de Ca, Mg e Fe na dieta alimentar. Embora Lippia alba e Justicia gendarussa L. tenham apresentado elevados valores de Ca, recomenda-se uma certa prudência quanto ao uso desse vegetal, devido aos significativos teores encontrados para Al.

The use of vegetables has become widely spread as nourishment, medicinal and cosmetic purposes in recent years. Due to the importance of the analytical study of this class of plants, and considering the growing interest about their inorganic composition that can be represented by the significant number of publications during the last years, the present work intended to analyze the occurrence of some minerals in ten herbs of popular therapeutic use that play important roles in the human metabolism. The studied samples were treated by two different methods: 1) dry ashing followed by acid treatment and 2) as tea by infusion of leaves in boiling water. Next, the metals were quantitatively determined by atomic absorption spectrophotometry (Ca, Mg, Mn and Zn), molecular absorption spectrophotometry (Al and Fe) or flame photometry (K and Na). By comparing the results found in this work with those of the daily recommended values by RDA and WHO, studies are suggested with respect to the use of Chenopodium ambrosioides L. as an alternative source of Na, K, Mg and Zn. Likewise, Ageratum conyzoides L. could be a complementary source of Ca, Mg and Fe in the human diet. Although Lippia alba (Mill.) N. E. Brown and Justicia gendarussa L. have presented high Ca levels, caution should be recommended to some extent concerning the use of this vegetable in view of its significant Al levels.

Determinations of Ca, Cu, Fe, Mg, Mn and Zn were evaluated in five different samples of medicinal plant leaves. Atomic absorption spectrometry was applied to the metals quantification. Except for Fe in Artemisia vulgaris L, significant levels of these elements were found in all investigated plant as compared to other vegetables which are abundant concerning that mineral content.

This review presents some characteristics related to slurry sampling in trace analysis in terms of its advantages, limitations and applications, as well as the latest advance in this area, such as mechanization, chemical modifiers, stabilization agents and others. The reviewed applications include foods, biological and geological materials.