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Seven elements, namely, arsenic, lead, cadmium, copper, zinc, iron and manganese were determined in 31 samples of Serbian plum brandies by applying atomic spectrometry techniques. Flame atomic absorption spectrometry was used for quantification of copper, iron, zinc, manganese, lead and cadmium; and hydride generation atomic spectrometry absorption for arsenic quantification. Measured concentrations of heavy metals and arsenic was assessed according to the Serbian regulations, official regulations of some other countries and in respect of microelements content in other similar distilled alcoholic beverages. Amounts of microelements in maximal recommended daily and weekly intake of plum brandy were determined. The influence of production (home made and industrial), type of wooden barrel (oak and mulberry), and duration of ageing process on the content of Zn, Cu, Fe and Mn in plum brandies, as well as coefficient of correlation between Cu content and pH value were also studied. [Projekat Ministarstva nauke Republike Srbije, br. 172053

BackgroundThe aim of this research was to determine the intensity and mechanisms of the cytotoxic actions of five extracts isolated from the endemic plant species Helichrysum zivojinii Černjavski & Soška (family Asteraceae) against specific cancer cell lines. In order to evaluate the sensitivity of normal immunocompetent cells implicated in the antitumor immune response, the cytotoxicity of extracts was also tested against healthy peripheral blood mononuclear cells (PBMC).MethodsThe aerial parts of the plants were air-dried, powdered, and successively extracted with solvents of increasing polarity to obtain hexane, dichloromethane, ethyl-acetate, n-butanol and methanol extracts. The cytotoxic activities of the extracts against human cervix adenocarcinoma HeLa, human melanoma Fem-x, human myelogenous leukemia K562, human breast adenocarcinoma MDA-MB-361 cells and PBMC were evaluated by the MTT test. The mode of HeLa cell death was investigated by morphological analysis. Changes in the cell cycle of HeLa cells treated with the extracts were analyzed by flow cytometry. The apoptotic mechanisms induced by the tested extracts were determined using specific caspase inhibitors.ResultsThe investigated Helichrysum zivojinii extracts exerted selective dose-dependent cytotoxic actions against selected cancer cell lines and healthy immunocompetent PBMC stimulated to proliferate, while the cytotoxic actions exerted on unstimulated PBMC were less pronounced. The tested extracts exhibited considerably stronger cytotoxic activities towards HeLa, Fem-x and K562 cells in comparison to resting and stimulated PBMC. It is worth noting that the cytotoxicity of the extracts was weaker against unstimulated PBMC in comparison to stimulated PBMC. Furthermore, each of the five extracts induced apoptosis in HeLa cells, through the activation of both intrinsic and extrinsic signaling pathways.ConclusionExtracts obtained from the endemic plant Helichrysum zivojinii may represent an important source of novel potential antitumor agents due to their pronounced and selective cytotoxic actions towards malignant cells.

From the Montenegrin spurge Euphorbia dendroides, seven new diterpenoids [jatrophanes (1-6) and a tigliane (7)] were isolated and their structures elucidated by spectroscopic techniques. The biological activity of the new compounds was studied against four human cancer cell lines. The most effective jatrophane-type compound (2) and its structurally closely related derivative (1) were evaluated for their interactions with paclitaxel and doxorubicin using a multi-drug-resistant cancer cell line. Both compounds exerted a strong reversal potential resulting from inhibition of P-glycoprotein transport.

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