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Zinc-Induced Genotoxic Effects in Root Meristems of Barley Seedlings

The pollution increase, as a result of the release into environment of genotoxic chemicals, including heavy metals, largely affects the ecosystems and the health of living organisms. Although zinc is not considered highly phytotoxic, its excess becomes noxious. In literature, the reports on zinc genotoxicity are equivocal. Therefore, the objective of this work was to evaluate the amplitude of cytogenetic damage induced in Hordeum vulgare L. cv. ‘Madalin’ after seed treatment with different concentrations (10, 100, 250, 500 μM) of Zn+2, provided as zinc sulphate and zinc acetate. The mitostimulatory effect was present at all concentrations of both zinc compounds. The rate of ana-telophase aberrations exceeded by 2 - 3 times the control, and the frequency of metaphase disturbances was 5.0-10.0 times higher than the control. The results indicate the clastogenic and aneugenic potential of zinc in barley and constitute a signal about the risks of its increasing presence into the environment, with repercussions on living systems, even on human health, due to the extensive use of zinc compounds including as pesticides.</p

EVALUATION OF THE cELF- EMF DELAYED EFFECTS ON DNA INTEGRITY OF THE NORMAL CELLS

The aim of this study was evaluation of the late effects of a 100 Hz and 5.6 mT electromagnetic field, applied continuously, on the DNA integrity of Vero cells assessed by alkaline COMET assay. Normal Vero cells were exposed to extremely low frequency electromagnetic fiel (100 Hz, 5.6 mT) for 45 minutes. The COMET assay was performed after 48 hours from the treatment. Exposed samples presented an increase of the number of cells with high damaged DNA as compared with non-exposed cells. Quantitative evaluation of the comet assay showed a significantly (<0.001) increase of the tail lengths, of the quantity of DNA in tail and of Olive tail moments, respectively. The analysis of the registered comet indices showed that extremely low frequency electromagnetic field of 100 Hz and 5.6 mT had a genotoxic impact on Vero cells

Evaluation of roundup-induced toxicity on genetic material and on length growth of barley seedlings

The study was performed in order to evaluate Roundup-induced genotoxic effects in Hordeum vulgare L. cv. Madalin root meristems and to analyze herbicide impact on length growth of barley seedlings. Caryopses were treated for 3 hours and 6 hours with 0.1%, 0.5%, 1.0% and 2.0% Roundup solutions (v/v), containing 0.36 mg ml–1, 1.8 mg ml–1, 3.6 mg ml–1 and 7.2 mg ml–1 glyphosate active ingredient. Mitotic index decreased in both exposure times with concentration increase. In 3-h treatment, its average values decreased from 4.73±0.31% to 1.51±0.43%, whereas in 6-h treatment this parameter declined from 3.86±0.92% to 0.62±0.15%. The highest ana-telophase aberration rates were noted in 3-h treatments (8.91%, 9.19%, 9.47%, 11.25%, comparatively to control – 5.99%). Roundup enhanced the number of metaphase disturbances proving its noxious effect on normal functioning of mitotic spindle. Seedling growth was negatively influenced at all tested concentrations in both exposure times. The length decreased as concentration increased, so that the average length is 7.5–9 times smaller than in control at the maximum concentration, in both exposures

EVALUATION OF THE AMPLITUDE OF CYTOGENETIC DAMAGE INDUCED BY TWO FOOD ADDITIVES IN WHEAT

Sulfites and metabisulfites, nitrates and nitrites are among the most utilized food additives. They can determine negative reactions in human body, but some of them showed genotoxic and carcinogenic action in various test-systems. In this study, we analyzed the amplitude of the cytogenetic changes induced by the exposure to different concentrations (0.1%, 0.5%, and 1.0%) of sodium nitrate (E251; SN) and sodium metabisulfite (E223; SMB) in wheat root tips meristems, by scoring the mitotic index and the frequency of division phases, the rates of ana-telophase chromosome aberrations, and of metaphase disturbances. Also, the influence on plantlet length was analyzed in young plantlets. The two chemicals increased the amount of chromosome aberrations, depending on concentration and time exposure

Considerations on the relationship between chromosome constitution and biochemical phenotype in five ecotypes of seabuckthorn

Seabuckthorn is a small tree showing pronounced morphological, physiological, biochemical and genetic variability, high ecological plasticity and large limits of resistance to unfavourable factors and to phytopathogens. It is largely exploited in biotechnological, nutritional, and pharmaceutical purposes, cosmetics domain and in environmental protective field. The possibility that some karyotype traits of five seabuckthorn ecotypes to be used as markers in relation with some specific biochemical features was discussed in this paper. There is intraspecific chromosome variability; the formula of haploid complement is different concerning the preponderance of chromosome morphotypes. Also a marked chemical heterogeneity was evidenced. At this research stage, the results not allow us to establish a direct relationship between some chromosome characteristics and certain morphological and biochemical parameters

ew potential antitumoral agents of polyphenolic nature obtained from Helleborus purpurascens by membranary micro- and ultrafiltration techniques

The in vitro action of some total aqueous and hydroalcoholic extracts and of their concentrate or permeate fractions, separated by membranary micro- and ultrafiltrations of the primary homogenates, obtained from Helleborus purpurascens ethnomedicinal plant, upon the cell protein biosynthesis, proliferation, viability and development of the HeLa cancerous cells cultures was investigated. The significant proteinsynthesis alteration, protein dynamics modification, decrease of total cell number, cell viability diminution, inhibitory impact upon the cell cultures development, during studied evolution period, suggest the behaviour of these polyphenolic hellebore extracts as in vitro active cytostatic and cytotoxic agents. Our preliminary characterization of these vegetal biopreparations as protein, mitotic, growth inhibitors offers the informational background for further investigations, on many other cancerous and normal cell lines and adequate experimental models to in vitro prescreening, as well as for their introduction in the in vivo antitumoral screening program on different experimental tumoral systems

Behavior of some enzymatic systems to the action of the cytostatic active EGlCP glucanic biopreparation upon HeLa neoplastic cells

Interference of an autochthonous cytostatic active EGlCP glucanic biopreparation (in dose of 1.5 mg/mL) with the activity of some key enzymes, involved in the development of active transmembranary transport, of the intermediary and energetic metabolism, as well as in cellular answer to the oxidative stress, of HeLa neoplastic cells has been investigated. The study revealed: the intensification of the membranary Na+-K+-ATP-ase, of the cellular Mg2+-ATP-ase, of the superoxide dismutase activities; the operating level attenuation of the of catalase, peroxidase, glutathion peroxidase, lactate dehydrogenase, alkaline phosphatase, acid phosphatase; the diminution of the malondialdehyde content. This functional interference with some cell enzymatic biomolecules has also induced the perturbation of the diverse membrane and metabolic processes, which was incompatible with the survival of HeLa tumoral cells The modulations of the cellular enzymatic equipment activity can be the consequences of the glucanic components direct (with the molecules of the miscellaneous enzymes) or indirect interactions ( with membrane or genetic apparatus) with some cell, subcell and molecular structures, implicated in the control and regulation of the biosynthesis and activity of the enzymatic biomolecules. The central element, which induces this enzymatic imbalance, appears to be the excess generation of the free radicals in the tumoral cells’ metabolism aggressed by glucanic constituents