جستجوی مقالات مرتبط با کلیدواژه « اکسید مس » در نشریات گروه « زیست شناسی »

Since nanoparticles cause increase of serious threat to human, animals and aquatic ecosystems, toxicity of copper oxide nanoparticles (CuO-NPs) on cyanobacteria Anabaena sp. in different concentrations were studied using growth inhibition test (OECD201). The negative Zander cyanobacteria were grown in the culture medium (Z-8-N) under optimum conditions of light, temperature and aeration in growth chamber. After starting the logarithmic growth phase, samples were exposed to various concentrations of copper oxide nanoparticles at intervals of 24, 48 and 72 hours. The number of cyanobacterial cells was daily counted and analyzed based on Probit analysis. The effective concentration (EC50), no effect concentration (NOEC), specific growth rate (μ), doubling time (G), percentage growth inhibition (I%) and chlorophyll content was calculated. Treatments and control were significantly different in terms of cell density and growth inhibition percentage at specific intervals. In addition, the chlorophyll content of different treatments showed significant difference compared to control. It seems reducing the efficiency of photosynthesis is one of the routes that lead to considerable damage of copper oxide nanoparticles on Anabaena sp.

Peroxidases are a group of oxidoreductases that are produced by a number of microorganisms and plants, and catalyse the reduction of peroxides. Peroxidases are widely used in clinical biochemistry and enzyme immunoassay. Horseradish peroxidase isoenzyme C (HRPC) is one of the characterized peroxidases. The structure of the enzyme is largely alpha helical. Peroxidase enzyme is detox important enzyme that to work process for getting rid of the cells of additional hydrogen peroxide under normal and stress conditions, including contamination with toxic levels of heavy metals, however, severe stress possible influence upon the activity of detoxification enzyme. Kinetics studies of peroxidase enzyme were performed using a spectrophotometer UV-Vis fitted with electronic control system at 35 °C and 45 °C and pH4 and in the presence ferric oxide and copper oxide. Kinetic parameters show that ferric oxide and copper oxide becomes caused the decrease of maximum speed (VMAX) and activity of the enzyme. Likely due to the ferri and copper ions have positively charged, these places are on or near the sites of glycosylation of enzyme and by their negatively charged are suitable binding sites for iron and copper. Likely binding of iron and copper are caused more changes of the secondary structure and makes random coil deduction more than alpha helix.

The aim of this study was to assess biochemical and histopathological effects of co-administration of thiamine and copper oxide and copper nanoprticles on the liver mouse. A total of the 30 adult mice were randomly divided into 5 groups (6 mice per each group) and considers on days 0, 10 and 20. Group A served control. Copper oxide and copper oxide nanoparticles (0.2 mg/kg) was injected intraperitoneally to groups B and C, respectively. The mice in groups E and D received the similar dose of copper oxide and copper nanoparticles along with thiamine (30 mg/l). As a result, influence of blood cells into liver sinusoids and inflammatory cells infiltration (neutrophil and lymphocyte) around the veins in groups B and C were observed. These abnormalities were less evident in the groups receiving thiamine to the extent that was near to control group. Significant differences were observed in the amount of catalase and superoxide dismutase in groups B and C on day 20 than to the control group. TBARS values in groups B and C on days 10 and 20 and in Group E at day 20 was significantly increased compared to control group. As a result, copper oxide nanoparticles causes damage to the liver and thiamine reducing the effects of the concurrent administration.

Increasing the application of copper oxide nanoparticles (NPs) in medicine (bactericidal agent) and other industries have raised serious concerns about ecotoxicology and ecophysiology effects on the aquatic animals. In this study¡ the effects of copper oxide NPs enriched yeast on the growth¡ survival; digestive enzymes activity and lipid metabolism in Artemia urmiana (AU) and Artemia franciscana (AF) were investigated. The experiment was designed in two treatments (non- enriched yeast as a control and enriched yeast with copper oxide NPs) and each with four replicates for both Artemia species. At the end of experiment¡ the results indicated that copper oxide NPs did not affect on the Artemia species growth rate but significantly increased both Artemia species survival. Also the results showed¡ copper oxide NPs did not affect on AU digestive enzymes activity¡ but significantly increased AF digestive enzymes activity. The effect of NPs on the body lipid content was investigated in Artemia species and the results revealed that copper oxide NPs significantly decrease AU lipid content but did not affect on AF. The results obtained in this experiment¡ suggest that the ecophysiological effects of copper oxide NPs different in Artemia urmiana and Artemia franciscana.

Glycyrrhiza glabra L. (Licorice) is one of the oldest medicinal plants in Iran and secondary metabolites present in the plant root is used in food and pharmaceutical industries. With the use of heavy metals as elicitors، plant secondary metabolite production can be increased. In this study، the effects of the concentrations of 1 and 10 µM of zinc oxide and copper oxide on the contents of reducing sugars (as precursor of secondary metabolites)، proline، glycyrrhizin، total phenolic compounds، flavonoids and anthocyanins in Glycyrrhiza glabra seedlings were investigated. Also، the correlation between the content of these metabolites in the treated seedlings was examined using Pearson''s test. The amount of reducing sugars at concentration of 10 µM zinc oxide was decreased. Whereas، the amounts of proline and glycyrrhizin under treatment 1 and 10 µM copper oxide and 1 µM zinc oxide compared with the control plants was increased. The content of total phenolic compounds was increased with increasing concentrations of copper oxide. The highest amount of flavonoids was observed at concentrations of 1 and 10 µM copper oxide. Anthocyanin content was increased in concentration of 1 µM copper oxide. Also، the tannin content of the Glycyrrhiza glabra seedlings at concentrations of 10 µM zinc oxide was increased. Based on the result it seemed that at concentrations of 1 and 10 µM copper oxide the amount of glycyrrhizin، phenolic compounds، flavonoids، anthocyanins were significantly increased، whereas، zinc oxide had no significant impact on the levels of these metabolites.