Cysteine as a green corrosion inhibitor for Cu37Zn brass in neutral and weakly alkaline sulphate solutions

The aim of this study was to investigate electrochemical properties of brass in neutral and weakly alkaline solutions in the presence of cysteine as a nontoxic and ecological corrosion inhibitor. Potentiodynamic measurements, open circuit potential measurements, as well as chronoamperometric measurements were the methods used during investigation of the inhibitory effect of cysteine on the corrosion behaviour of brass. Potentiodynamic measurements showed that cysteine behaves as a mixed-type inhibitor in the investigated media. Based on polarization curves for brass in a weakly alkaline solution of sodium sulphate at varying cysteine concentrations, an interaction occurs between Cu⁺ ions and the inhibitor, resulting in the formation of a protective complex on the electrode surface. The results of chronoamperometric measurements confirm the results obtained by potentiodynamic measurements. Optical microphotography of the brass surface also confirms the formation of a protective film in the presence of a 1?×?10^?4 mol/dm³ cysteine. Adsorption of cysteine on the brass surface proceeds according to the Langmuir adsorption isotherm.     

In vitro toxicity of selected fungicides from the groups of benzimidazoles and demethylation inhibitors to Cladobotryum dendroides and Agaricus bisporus

Twenty microfungal isolates were collected from diseased fruiting bodies of Agaricus bisporus sampled from Serbian mushroom farms during 2003–2007. Based on morphological characteristics and pathogenicity tests, the isolates were identified as Cladobotryum dendroides. The isolates of C. dendroides and A. bisporusF56 and U3 were tested for sensitivity to several selected fungicides in vitro. C. dendroides isolates were found to be more sensitive to prochloraz manganese and flusilazole + carbendazim than to the other fungicides tested (EC₅₀ values were 0.09 and 0.11 mg L^{? 1}, respectively) and weakly resistant to thiophanate-methyl (EC₅₀ values ranged between 6.53 and 12.09 mg L^{? 1}). Selectivity indexes of the tested fungicides on both C. dendroidesand A. bisporusindicated that thiophanate-methyl, cyproconazole + carbendazim and flusilazole + carbendazim had much less selective fungitoxicity than benomyl, carbendazim and prochloraz manganese.     

Evaluation and validation of two different chromatographic methods (HPLC and LC-MS/MS) for the determination and confirmation of ochratoxin A in pig tissues

This study was undertaken to compare two different analytical methods for the determination and confirmation of ochratoxin A (OTA) in blood serum, kidney and liver of pigs. Sample clean-up was based on liquid-liquid phase extraction. The detection of OTA was accomplished with high-performance liquid chromatography (HPLC) combined either with fluorescence detection (FL) or electro spray ionization (ESI+) tandem mass spectrometry (MS–MS). Comparative method evaluation was based on the investigation of 90 samples of blood serum, kidney and liver per animal originating from different regions of Serbia. The analytical results are discussed in view of the respective method validation data and the corresponding experimental protocols. In general, analytical data obtained with (LC–MS–MS) liquid chromatography electro spray tandem mass spectro metry detection offered comparable good results at the sub-ppb concentration level. The results indicate that the liquid chromatography electro spray tandem mass spectrometric (LC-MS/MS) method was more specific and sensitive for the analysis and confirmation of ochratoxin A in pig tissues then high pressure liquid chromatography (HPLC) method after methylation of OTA.     

Fungicide sensitivity of Trichoderma spp. from Agaricus bisporus farms in Serbia

Trichoderma species, the causal agents of green mould disease, induce great losses in Agaricus bisporus farms. Fungicides are widely used to control mushroom diseases although green mould control is encumbered with difficulties. The aims of this study were, therefore, to research in vitro toxicity of several commercial fungicides to Trichoderma isolates originating from Serbian and Bosnia-Herzegovina farms, and to evaluate the effects of pH and light on their growth. The majority of isolates demonstrated optimal growth at pH 5.0, and the rest at pH 6.0. A few isolates also grew well at pH 7. The weakest mycelial growth was noted at pH 8.0–9.0. Generally, light had an inhibitory effect on the growth of tested isolates. The isolates showed the highest susceptibility to chlorothalonil and carbendazim (ED₅₀ less than 1 mg L^?1), and were less sensitive to iprodione (ED₅₀ ranged 0.84–6.72 mg L^?1), weakly resistant to thiophanate-methyl (ED₅₀ = 3.75–24.13 mg L^?1), and resistant to trifloxystrobin (ED₅₀ = 10.25–178.23 mg L^?1). Considering the toxicity of fungicides to A. bisporus, carbendazim showed the best selective toxicity (0.02), iprodione and chlorothalonil moderate (0.16), and thiophanate-methyl the lowest (1.24), while trifloxystrobin toxicity to A. bisporus was not tested because of its inefficiency against Trichoderma isolates.     

Exploring the Park–People Relation: Collection of <Emphasis Type="Italic">Vaccinium Myrtillus</Emphasis> L. by Local People From Kopaonik National Park in Serbia

Exploitation of certain resources within a protected area on a sustainable basis could contribute to higher living standards of rural people, particularly those in poor countries, and decrease conflicts between these populations and park authorities. This article presents data from a case study of Kopaonik National Park (NP), Serbia, which is a park with natural resources, most notably bilberries, which have always been relied on by local people. Vaccinium myrtillus traditionally has been collected for decades in Kopaonik NP and used by local people. However, little is known about the socioeconomic and ecological relations that affect the collection and use of this species. The aim of the present study was to understand how local people collect bilberries in Kopaonik NP and what their attitudes toward the park are. Household questionnaire data were used to examine how local people collect bilberries and how to improve the relations between local people and NP authorities. The survey questionnaire included 52 households from 7 local communities, and we applied a purposive sampling strategy. In addition, expert interviews were conducted, and from these data we obtained a broader understanding of the relation between local people and NP authorities. The results indicate that in Kopaonik NP, there is a conflict between pickers and NP authorities. Sustainable management should be directed toward the protection of bilberries. Education of local people is a key element in the sustainable collection and protection of natural resources.     

Heavy metal concentration in fish tissues inhabiting waters of “Buško Blato” reservoar (Bosnia and Herzegovina)

Heavy metals concentration (mercury, lead, cadmium, arsenic, copper, zinc and chromium) in tissues (muscles, liver, kidney and gonads) of Dalmatian barbelgudgeon, the nase, the souffie and brown trout, inhabiting waters of Busko Blato reservoir in Bosnia and Herzegovina, has been determined by atomic absorption spectrophotometry. The meat of the tested fish sorts does not contain elevated concentration of most analyzed heavy metals with exception of lead (higher than MAC in Italy, Germany and Denmark) and mercury (in muscles of brown trout higher than MAC in most countries). The lowest level of all heavy metals is always detected in gonads, with higher values in fry compared to milt for copper, zinc, chromium and arsenic. The highest copper concentration is observed in the liver from the souffie which is suggested as a suitable biomonitor for copper intoxication. In muscles of all fish sorts, lead was always present in much higher concentration than cadmium, while in kidneys of most fish sorts, lead and cadmium concentrations were similar. We showed that bioaccumulation of some heavy metals in the fish sorts analyzed is tissue and sex dependent. Also, we concluded that the small water exchange in reversible shallow reservoir does not induce elevated concentration of heavy metals in fish tissues inhabiting Busko Blato.     

Precipitation composition and wet deposition temporal pattern in Central Serbia for the period from 1998 to 2004

Bulk samples collected on a daily basis at three principal meteorological stations in central Serbia were analyzed on chloride (Cl(-)), nitrate [Formula: see text], sulfate [Formula: see text], sodium (Na(+)), ammonium [Formula: see text], potassium (K(+)), calcium (Ca(2+)), and magnesium (Mg(2+)) in addition to precipitation amount, pH and conductivity measurements over the period 1998-2004. The data were subjected to variety of analyses (linear regression, principal component analysis, time series analysis) to characterize precipitation chemistry in the study area. The most abundant ion was [Formula: see text] with annual volume weighted mean concentration of 242 microeq L(-1). Neutralization of precipitation acidity occurs both as a result of the dissolution of alkaline compounds containing Ca(2+), Mg(2+), and K(+) as well as the absorption of ammonia. The ratio of [Formula: see text] was above 5, which indicated that the combustion process of low-grade domestic lignite for electricity generation from coal-fired thermal power plants was the main source of pollution in the investigated area. A considerable mean annual bulk wet deposition of SO(4)-S determined by precipitation amount and concentrations of sulfate in the precipitation was calculated to be 12-35 kg ha(-1).     

Genotoxicity screening of the river Rasina in Serbia using the Allium anaphase–telophase test

Evaluation of the presence of genotoxic substances is especially important in rivers that serve as a source of drinking water. Nine water samples collected along the river Rasina in Serbia were analyzed for potential toxic and genotoxic effects using the Allium anaphase-telophase test. Inhibition of root growth relative to the negative control (synthetic water) was observed in all samples. Analysis of the genotoxic potential, through scoring anaphase and telophase aberrations, showed that in seven of the nine samples the level of aberrations was significantly increased relative to the negative control but was lower than that obtained for the positive control (methyl methanesulfonate). Changes in the relation between spindle and chromosome types of aberrations were found in some samples, indicating differences in the potential genotoxic substances present at the analyzed sites. The data, which were obtained from samples collected at the highest level of river water, warn that during periods of low flow the values could reach genotoxic activity. The Allium anaphase-telophase test can be recommended as an monitoring system, that can serve as the first alert for the presence of genotoxic environmental pollutants.     

Malondialdehyde concentrations in the intestine and gills of Vardar chub (Squalius vardarensis Karaman) as indicator of lipid peroxidation

Environmental Science and Pollution Research - A lipid peroxidation product, malondialdehyde (MDA), was studied in Vardar chub (Squalius vardarensis Karaman) as an indicator of oxidative stress,...