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Recently, Samoans have faced to alarming increase in the prevalence of obesity related diseases, which are connected to the consumption of imported calorie-rich and nutrient-poor food products. It is believed that the re-introduction of native diet may mitigate these negative trends. In Samoa, the seeds of Adenanthera pavonina, an underutilized leguminous tree, are popularly eaten when roasted. Although the seeds are also used in traditional medicine to treat inflammatory and cardiovascular diseases, information on their nutrients and any compounds potentially reducing risks of related health disorders is very limited. Therefore, the objective of this study was to analyse the nutrients and compounds potentially reducing risks of overweight- and obesity-related health problems in raw and roasted A. pavonina seeds from Samoa. The standard analytical and microbiological methods, namely gas chromatography–mass spectrometry, inductively coupled plasma optical emission spectrometry, high-performance liquid chromatography with fluorescence detection, ultrahigh-performance liquid chromatography-tandem mass spectrometry, and Czech technical standard methods, were used for the determination of fatty acids, minerals, tocopherols, phenolic compounds, and B vitamins, respectively. The analyses showed that the lignoceric (17.59% and 18.24%), linoleic (39.80% and 37.88%), and oleic acids (14.67% and 14.75%) were the most abundant in the oil of raw and roasted seeds, with the unsaturated forms present in higher amounts than saturated. The seeds were found to be rich of vitamin E (33.09 and 15.94 mg/100 g), whereas the contents of vitamins B1, B2, B3, and B6 were rather low. Calcium, magnesium, phosphorus, potassium, and sulphur were the minerals found in the highest concentrations. Salicylic acid (201.01 and 151.95 µg/100 g) has been detected in higher amounts than other phenolic compounds. In summary, the findings of this study indicate that the both raw and roasted seeds of A. pavonina are good sources of various health-beneficial nutrients, including those reducing the negative effects of obesity.

Forest soils near industrial zones can be endangered by acid deposition and by dust deposition containing potentially toxic elements (PTEs). Soils of the study area are acidified and the surface enrichment with Cd, Cu, Pb, and Zn reflects anthropogenic contamination. Two forms of all PTEs were evaluated: potentially mobilized (2M nitric acid extraction) and mobile (0.01M CaCl 2 extraction) -the most toxic form. Negligible amounts of Cu and Pb were found in the mobile form. Pb mobilization is decreased by co-emitted bases and Cu mobilization is mainly controlled by soil reaction. These elements represent just a potential risk for the ecosystem. The mobile forms of Cd, Zn, and Mn account for approximately 30% of potentially mobilized forms in organic horizons. These elements could pose a problem to ecosystem vitality. Cd is toxic at small concentration and its content in mobilized form approaches the critical load. Cd can be considered the most dangerous element in the study area. Zn concentration is not reaching the limit value. Mobilization of Zn and Pb is mainly controlled by Ca and Mg content. The highest concentrations of Mn were found in the mineral horizons. It predicates a geogenic origin. The lowest percentage of the mobile form is in mineral horizon and its mobilization is controlled mainly by pH. Based on these results, a direct damage of forest by PTE contamination in the Silesian Beskids can be excluded. Lower contamination level along with acid condition and P deficiency could act as a permanent stress factor. Stressed forest is more predisposed e.g. to frost or insect damage.

The recent rapid expansion of nanotechnologies has increased concern over the impact of engineered nanoparticles (ENPs) on the environment and biota. Although the toxicity of ENPs has received considerable attention in the recent years, there are still gaps in our knowledge of the mechanisms responsible for their effects. In this study, we tested the toxicity of various metal oxide ENPs (Al2O3, CuO, Fe3O4, MnO, TiO2, and ZnO), including nanowires together with their bulk counter particles and soluble metal salts, on germinating seeds of Sinapis alba L. Fe3O4, TiO2, MnO2, and Al2O3 ENPs did not negatively affected seed germination at any tested concentrations. However, CuO and ZnO ENPs showed a dose-dependent inhibition of germination. Metal ions were more toxic than metal oxide particles at corresponding concentrations. The highest toxicity was exhibited by Cu, followed by Zn, Fe, Al, and Mn ions. A comparison of ENPs with bulk materials did not reveal significantly higher ENP toxicity. Similarly, nanowires showed effects similar to other nanoparticles and bulk materials. Our results indicate that the nanosize or shape of particles did not play a crucial role, whereas metal ions released into cultivation media and accumulated in seedlings contributed significantly to the phytotoxicity of metal oxides.

In order to determine the mobility of Pb, Zn and Cd in soils from the Přibram region (Czech Republic) heavily contaminated by metallurgy, two profiles of alluvial soils were closely studied. Total contents of heavy metals were determined a�er digestion with a mixture of HF and HClO4. Heavy metal mobility was assessed using the mobility factor (MF) that represents the proportion of heavy metals present in the exchangeable and carbonate bound fraction based on the Tessier’s sequential extraction procedure. The MF ranged from 2 to 46% for lead, 19 to 62% for zinc and 61 to 94% for cadmium. The profile distribution of zinc and cadmium showed a variable development with depth, which is caused by high amounts of these metals present in labile forms. The profile distribution of lead (the least mobile metal) is characterized by a gradual decrease with depth. The results indicate a higher contamination of the soil profile situated 2.5 km away from the smelter in comparison with the profile in its close vicinity. This fact confirms the existence of extreme fluvial contamination.

STREET R., SZ AKOVA J., DRABEK O., MLADKOV A L. (2006): The status of micronutrients (Cu, Fe, Mn, Zn) in tea and tea infusions in selected samples imported to the Czech Republic. Czech J. Food Sci., 24: 62–71. A total of 30 tea samples of different origins, thirteen green tea samples, thirteen black tea samples, two semi-fermented tea samples and one white tea, imported to the Czech Republic, were collected and analysed for the total content of copper, iron, manganese, and zinc in tea leaves and tea infusions. The total contents of metals in tea leaves differ according to the type of tea (green or black) and are probably influenced by many other factors, e.g. soil properties. The total contents of Mn were much higher compared to the total contents of Cu, Fe, and Zn, and varied between 511–2220 mg/kg. To compare easily hot water soluble concentrations of Cu, Fe, Mn and Zn, 5 min, 60 min, and 24 h infusions were prepared. The extractability of the elements was in the order Cu > Zn > Mn > Fe. The proportions of the element contents in the infusion related to the respective total contents in leaves were 30 ± 16% Cu, 26 ± 10% Zn, 18 ± 10% Mn, and 1.5 ± 0.8% Fe, respectively. The results confirmed that tea infusion can be an important dietary source of Mn.