Understanding element composition of medicinal plants used in herbalism-A case study by analytical atomic spectrometry

Assessment on Solubility and Solid Phase Chemical Fractionation of Manganese in Hot Infusions of Green and Roasted Mate

A solid phase chemical fractionation (SPCF) of the Mn in hot infusions prepared from commercial samples of roasted (RM) and green mate (GM) using a chelating resin Chelex 100 (NH4+ form) was performed to assess the relative lability of this essential trace element (ETE). In addition, total Mn contents in the RM and GM samples and their infusions were determined by flame atomic absorption spectrometry. Total polyphenol (TP) contents and the presence of soluble melanoidins (SM) were correlated with the Mn solubility in the RM and GM infusions. From the SPCF study, it was possible to observe that the soluble Mn forms in the mate infusions were essentially associated with relatively noninert chemical species (98.4-99.7%), suggesting that they may be potentially bioavailable. In addition, the soluble Mn contents in the GM infusions were 20.5% higher than those found in the RM. Mn solubility in the (RM) infusions was highly and directly correlated (r = 0.99) with the soluble TP, while in the GM infusions, it was high and inversely correlated with soluble TP (r =  -0.87). On the other hand, Mn solubility in the RM and GM infusions was weakly correlated with the SM. It should be stressed that GM infusions can contribute with 57 and 44% more than the RM infusions to the recommended adequate intake of Mn established for females and males, respectively. Moreover, this work is the first to evaluate and compare the relative lability of Mn and its solubility in the RM and GM infusions.

Artemisia arborescens and Artemisia inculta from Crete; Secondary Metabolites, Trace Metals and In Vitro Antioxidant Activities

BACKGROUND

Currently, the use of medicinal plants has increased. Artemisia species have been used in several applications, including medicinal use and uses in cosmetics, foods and beverages. Artemisia arborescens L. and Artemisia inculta are part of the Mediterranean diet in the form of aqueous infusions. Herein, we aimed to compare the secondary metabolites of the decoctions and two different extracts (methanolic and aqueous-glycerolic) of these two species, as well as their antioxidant capacity and trace metal levels.

METHODS

Total phenolic, total flavonoid, total terpenes, total hydroxycinnamate, total flavonol, total anthocyanin contents and antioxidant/antiradical activity were determined, and GC/MS analysis was applied to identify and quantify phenolics and terpenoids. Trace metals were quantified with ICP-MS.

RESULTS

Aqueous-glycerolic extracts demonstrated higher levels of total secondary metabolites, greater antioxidant potential and higher terpenoid levels than decoctions and methanolic extracts. Subsequently, the aqueous-glycerolic extract of a particularly high phenolic content was further analyzed applying targeted LC-MS/MS as the most appropriate analytic tool for the determination of the phenolic profile. Overall, twenty-two metabolites were identified. The potential contribution of infusions consumption to metal intake was additionally evaluated, and did not exceed the recommended daily intake.

CONCLUSIONS

Our results support the use of these two species in several food, cosmetic or pharmaceutical applications.

Novel ICP-OES-Based Method for the Reliable Determination of the Total Content of 15 Elements in Yerba Mate Drinks along with the Determination of Caffeine and the In Vitro Bioaccessibility of the Compounds

A fully validated inductively coupled plasma optical emission spectrometry (ICP-OES)-based method combined with a simplified sample preparation procedure for the determination of up to 15 elements (Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn) in caffeinated yerba mate (YM) drinks was proposed. Various "green" treatments (acidification or dilution with a HNO₃ solution and direct analysis of untreated YM with or without sonication (US)) that could replace the traditional total sample decomposition before spectrometric measurements were tested and compared. The key selection parameter was the analytical performance of the ICP-OES method obtained with each sample preparation procedure in terms of the precision and the trueness of results and limits of detection (LODs) of elements. It was found that the acidification of YMs with concentrated HNO₃ to 5%, supported by US (10 min, room temperature (RT)), provided the best results, i.e., LODs at 0.11-8.5 ng g^-1, precision below 5%, and trueness better than 5% (97.0%-105% as recoveries). Eleven YM drinks, commercially available on the Polish market, were analyzed with the proposed method. In addition to the mineral content, the concentration of caffeine in all analyzed YMs was determined and compared. Finally, the studies were completed by determining the bioaccessible fraction of selected elements and caffeine in YMs using in vitro gastrointestinal digestion (GID) in order to evaluate the nutritional value/risk assessment of these drinks. Accordingly, the bioaccessibility of nutritious elements (Ca, Fe, Mg, Mn, Zn) and caffeine was within 40%-59%. Except for Mn, it was established that by drinking daily 1 L of YMs, the recommended dietary intakes (RDIs) of the aforementioned essential elements were covered to a low degree (<4.5%). Hence, they are not an important source of these elements in the human diet. On the other hand, potentially toxic elements (Al, Ba, Sr) were found in a relatively inert form. Opposite to minerals, YMs can supply human organisms with quite high amounts of natural caffeine in bioaccessible form (31-70 mg per serving).

ICP-MS determination of elemental abundance in traditional medicinal plants commonly used in the Kingdom of Saudi Arabia

Medicinal plants are widely used in the Kingdom of Saudi Arabia to treat various ailments in the form of folk medicine. Forty four such medicinal plant samples were collected from local markets and evaluated for the presence of 14 elements (Mn, Cr, Co, Ni, Cu, Mo, Al, Pb, Ba, Zn, Ag, Hg, Bi, Cd). Microwave-assisted digestion with inductively coupled plasma-mass spectrometry (ICP-MS) was applied to determine the elemental composition in these medicinal plants. Widespread occurrence of these elements was observed in all plant samples, except for Bi and Co where the lowest mean values of 0.03 ± 0.04 and 0.03 ± 0.15 were observed, respectively. The descending order for mean (μg/g) elemental occurrence observed was as follows: Ba > Al > Zn > Ni > Mn > Ba > Hg > Mo > Cu > Cr > Ag > Cd > Co > Bi, whereas the range for these elements in the 44-medicinal plants was as follows: Pb > Al > Zn > Ni > Mn > Cu > Mo > Ag > Ba > Hg > Co > Cd > Cr > Bi. Pb, Hg and Cd were found beyond the maximum limits in these medicinal plants, while the remaining elements were found well within the range of maximum limits. A number of medicinal plants showed high amounts of these elements. Some plants contained more than one element, such as Foeniculum vulgare Mill (Pb, Hg, Cd), Ricinus communis (Pb, Cd), Vigna radiata (Pb, Cd) and Sesamum indicum (Pb, Hg). The data matrix was validated through the statistical tools of principal component analysis (X² = 160.44, P = .00), Pearson's correlation (P = .01 and 0.05), and K-mean cluster analysis (F = 104.55, P = .00). The findings of the study provide baseline data for the comparative analysis of these medicinal plants, which may help select safe medicinal plants in terms of consumer-based use and its utilisation for the treatment of various ailments.

Multi-elemental Analysis and Health Risk Assessment of Commercial Yerba Mate from Brazil

Consumption of yerba mate occurs mostly in the form of hot infusion (chimarrão). Water solubility of elements found in commercialized yerba mate is needed to establish nutritional value and risks associated with potentially toxic elements. In this study, yerba mate products marketed in three Brazilian states (Paraná, Santa Catarina, and Rio Grande do Sul) for chimarrão were analyzed. Total (dry product) and hot water-soluble concentrations of Al, As, B, Ba, Ca, Cd, Co, Cs, Cu, Fe, K, Li, Mg, Mn, Mo, Ni, P, Pb, Rb, S, Se, Sr, Ti, V, and Zn were determined by inductively coupled plasma mass spectroscopy (ICP-MS). Total concentrations of the ten top elements followed the order of K>Ca>Mg>Mn>P>S>Al>Fe>Ba>Zn. The most soluble elements were B, Cs, Ni, Rb, and K, with values greater than 80%. The lowest water-soluble elements were V, Fe, and Ti (values <10%), followed by Ba, Cd, Al, As, Sr, Ca, and Pb with solubility between 10 and 20%. Although total Cd levels in yerba mate products were often above those permitted by South America legislation, estimated daily consumption intake indicated no risk associated with the chimarrão beverage. Manganese was the micronutrient with the highest total and soluble levels in yerba mate, which surpassed recommended daily intake values when considering a consumption amount of 50 g day^-1 of yerba mate as chimarrão. The consumption of yerba mate is safe and contributes to intake of nutrients. The Cd and Pb reference values of yerba mate products sold in South America should be revised.

Total reflection X-ray fluorescence analysis of elemental composition of herbal infusions and teas

BACKGROUND

The elemental composition of herbal infusions and teas has not been sufficiently investigated. It could potentially be used for defining fingerprints for individual herbal / tea infusions, differentiation of botanical families, detecting the influence of packaging, and other purposes. The objective of this study was to determine the elemental composition, including the trace element content, of various herbal infusions and teas by means of total reflection X-ray fluorescence analysis (TXRF), with a chemometrics approach using principal component analysis (PCA).

RESULTS

This study determined the elemental composition of various herbal infusions and teas, including trace elements, using total reflection X-ray fluorescence (TXRF). The methodology for the sample preparation was established, including the multiple-steepings procedure for the two tea samples (Oolong and Pu-erh). Data from 29 samples were collected. We hypothesized that the elemental content of infusions could reflect certain features, such as the influence of processing and the type of tea.

CONCLUSION

A chemometric approach (PCA) was applied, and differences between teas and herbal infusions were found. This was further corroborated by explicit differentiation of one botanical family, Theaceae. The influence of packaging (tea bags) on herbal material was identified. The three types of tea (Camellia sinensis) appeared to be separated with PCA, and elemental concentrations in Pu-erh changed with multiple steepings.