Assessment of Heavy Metal Pollution in Water and Sediments from the Ghalechay River,Baychebagh Copper Mine Area,Iran

The concentrations of selected heavy metals in sediments and waters in Baychebagh copper mine were determined using ICP-OES. Except for Co, the average concentrations of Cd, Cu, Pb, and Zn in sediments from the Ghalechay River in the district exceed the world-average shale and continental upper crust value. Enrichment factors for Pb, Cu, and Cd were significantly enriched in sediments, indicating environmental contamination. Geoaccumulation index calculated for different sampling stations indicates that the sediments are unpolluted with respect to Co and Zn while unpolluted to moderately polluted with Cu and highly polluted with Pb and Cd. The Sediment Quality Guidelines (SQGs) suggest that Cd and Pb may pose the highest risk for the environment. Sequential extraction analyses of sediments revealed that Cu, Co, Pb, and Zn bound to extractable, carbonate, reducible and oxidizable fractions are lower than residual fraction. About 10% of the total Pb was associated with the exchangeable fraction, indicating remobilization, while Cd (89%), Pb (73%) Co (58%), Cu (76%), and Zn (68%) closely associated with the residual and oxidizable fractions, resulting in their environmental immobility. The residual forms are not expected to be released under normal conditions in the river and could be considered an inert phase.     

Biological studies of synthesized silver nanoparticles using <Emphasis Type="Italic">Prosopis farcta</Emphasis>

The evaluation of cytotoxic and apoptotic activities of silver nanoparticles (Ag-NPs) synthesized by aqueous extract of Prosopis farcta was investigated against lung (A549) and colon (HT-29) cell lines. The cytotoxic activity of nanoparticles was performed using MTT assay, while their apoptotic activity was tested using TUNEL method. The obtained results of MTT showed that the cell viability of A549 was dependent on the nanoparticles concentration and incubation time. Therefore, although the cytotoxic effect increased as the Ag-NPs concentration and incubation time heightened, yet the viability of HT-29 cells seems to be dependent only on the incubation time. The apoptotic results of the nanoparticles showed more than 50% of apoptosis on A549 and HT-29 cell lines, which in this case, HT-29 demonstrated 100% apoptosis at concentrations of more than 400 µg/ml. It seems that Ag-NPs synthesized using P. farcta extract can serve as anti-cancer agent in the treatment many cancers through creating or discovering new drug forms.     

Synthesis and evaluation of cytotoxicity of 6-amino-4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitriles

Several derivatives of 6-amino-4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitriles were synthesized via Biginelli type reaction and tested for their anti-proliferative activity on human breast cancer (MCF-7) and human colon carcinoma (HT29) cell lines. Malignant and non-malignant cells were cultivated in RPMI medium and incubated with different concentrations of these pyrimidines. Cell viability was evaluated by MTT assay. Apoptotic cells were determined using DAPI (4'-6-diamidino-2-phenylindole) and propidium iodide staining of DNA fragmentation by flow cytometry (sub-G1 peak). 6-Amino-4-(4-chlorophenyl)-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile and 6-amino-4-[4-dimethylamino)phenyl]-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile decreased the viability of MCF-7 and HT29 cells, in contrast to L929 cells. These compounds induced a sub-G1 peak inflow cytometry histograms of treated cells indicating that apoptosis is involved in their toxicity.