Effect of high levels of organic selenium on glutation-peroxidase (GSH-Px) activity in blood plasma of broilers

An experiment lasting 45 days was performed on 125 Hybro broilers divided into five groups. All compounds for broiler feed mixes used in the experiment contained 0.15 mg Se/kg, in the form of sodium selenite. The control group (K-group) of broilers was fed mixes without added organic selenium, and the experimental groups with mixes to which selenium, in the form of selenized-yeast, was added in quantities of 2, 5, 10, or 15 mg/kg. Selenized yeast (ICN - Gaienika) was obtained from beer yeast and contained 1.51, or 1.45 mg/g total, or organically bound selenium. At the beginning of the fattening period, GSH-Px plasma activity in broilers of the K-group ranged around 16.55 μkat/L, while GSH-Px plasma activity in broilers of experimental groups was statistically significantly higher, but without any major differences among the individual groups (on the average 25.53fjkat/L). In the blood plasma of K-group, GSH-Px activity dropped already in the second week of life and was maintained at a relatively constant level (about 10 μkat/L) until the end of the experiment. The same phenomenon was observed in the experimental groups, but the trend of declining GSH-Px activity in blood plasma was more expressed, and, contrary to the control group, was expressed also in the later phases of the experiment. In the 3rd week of the fattening period, GSH-Px plasma activity in broilers of the control and experimental groups was relatively equal, and then the plasma activity of GSH-Px in broilers of the experimental groups decreased, but there were no major differences among the individual groups

Influence of Microbial Community on Power Generation Using MFC System

Introduction: Global worldwide population and urbanization in general have created an increasing need for new energy sources. These sources need to be renewable, but it is also very important to respect the principles of environmental protection. Microbial fuel cells (MFC) are a green technology that is attracting more and more attention in the last decade. MFC presents a system which produces electrical current through metabolic processes of microorganisms such is the decomposition of organic matter. In this process chemical energy is directly converted into electrical energy [1-3]. The performance of MFC depends on several factors: temperature, the composition of the sediment, the material from which the electrodes are made, but certainly, one of the prominent factors is the activity of a microbial community. In this paper, efficiency of two MFC systems will be compared to obtain the highest current and power generation. One of them contains only river sediment as a source of microorganisms, while the other was biostimulated by microorganisms isolated from the same river sediment [2-3]. Methods: The river sediment was placed between a set of inox electrodes in a plastic container, with a total volume of 201 cm3 (MFC I). The second MFC (MFC II) was made in the same way, but a consortium of microorganisms, Clostridium sp., Bacillus sp. and Tepidibacter sp. isolated from the river sediment was added to the sediment. The set of resistors already established in our previous studies were used for the measurement of the amount of voltage, which was then used to obtained the values of current and power [4]. Results: After five days of measuring the generated voltage via MFC I and II, the results for current and power density were obtained. In MFC I, the highest current density was recorded on the fifth day and was 76 mA/ m3 while the power was 1.5 mW/m3 . With MFC II, the results were visibly higher, where the current was increased three times (up to 210 mA/m3 ), and the power by as much as 4 times higher compared to the results of MFC I (6 mW/m3 ). Conclusion: Results show that MFC I has lower values than the sediment stimulated by a consortium of microorganisms in the MFC II. The community of microorganisms greatly contributes to improving the performance of the sediment itself, by generating more power density

Microbial Recovery of Copper and Zinc from Wasted Electronic Parts

Recycling of electronic waste is crucial not only from the viewpoint of waste treatment but also from aspect of the recovery of valuable metals [1]. The aim of our study was to investigate the potential of using the Acidithiobacillus sp. B2, to solubilize metals (Cu and Zn) from electronic waste. Methodology: Chemical analysis of electronic waste and pyrite The electronic waste (after separating of the plastic parts) and pyrite were pulverized and sieved through a 63 µm stainless steel sieve in preparation for chemical and leaching studies. Electronic waste preparation for the leaching experiment The presence of alkali components in electronic waste is considered inconvenient for the reaction between the electronic waste and the acidic iron(III) sulphate solution. Hence, it is necessary to neutralize the electronic waste before adding the bacterial culture which would generate the oxidant. Before the leaching experiment, electronic waste was dispersed in 0.05 M H2 SO4 solution, shaken for 48 h, filtered from the solution, washed out with deionized water and dried at 110 °C [2]. Preparation of pyrite for the leaching experiments The pyrite concentrate for the leaching experiments was prepared by treating with a 0.5 mol/dm3 sulphuric acid solution (pH ~ 0.5) (solid to liquid phase ratio 1:5 m/V), and mixing with a mechanical stirrer at a room temperature overnight. Then, the solution was decanted, washed with deionized water and dried at 80 °C to a constant mass [2]. Leaching experiments The leaching experiments were carried out with bacterium Acidithiobacillus sp. B2. Experimental conditions were: leaching period of 20 d, 50 ml leaching solution (g/dm3 ): (NH4 )2 SO4 (3), K2 HPO4 (0.5), MgSO4 x 7H2 O(0.5), KCl (0.1), Ca(NO3 )2 (0.01), at a pH of 2.5 in 150 mL Erlenmeyer flasks at a pulp density of 10% (m/V) (5 g leaching substrate in 50 ml solution). The pH of the leaching solution was maintained at a constant value during the leaching process. One half of the substrate was pyrite and the other was an electronic waste. The initial number of microogranisms was 107 per mL, determined by the Most Probable Number method. The control suspension had the same chemical content and pH value as the suspension with Acidithiobacillus sp. B2 but the Acidithiobacillus sp. B2 culture had been inactivated by sterilization. The study was realized on a horizontal shaker. The incubation temperature was 28 °C [2]. Results and conclusions: The results of the effective metal leaching (calculated by subtraction of percentage metal leaching in the control suspension from that in the Acidithiobacillus sp. B2 suspension) are as follows: Zn (38%)>Cu (35%). The obtained results demonstrate that Acidithiobacillus sp. B2 was able to grow in the presence of electronic waste and may be “green” agents in the area of circular economy and sustainable development

Antibacterial and antifungal effect of S- and N-AgMOF-CDs nanocomposites

Bacterial and fungal resistance is an increasingly severe problem. The high microbial resistance appears to be the consequence of the unconsidered use of antibiotics and antifungal drugs, and poor infection control in hospitals. Fighting microbial resistance by using new substances based on organic nanoparticles, carbon dots (CDs) may be a promising strategy in developing new therapeutic approaches. The metal-organic frameworks (MOFs), due to their unique features including high cargo loading, biodegradability, and ability of modification have become an attractive group of nanomaterials used in several fields including nanomedicine. In the current study, we synthesized N- and S-CDs@AgMOFs nanocomposites, new substances based on organic CDs nanoparticles inserted in MOFs structures. One Gram-positive (Bacillus subtilis), one Gram-negative (Escherichia coli) bacteria, and one fungi (Candida albicans) were treated with different concentrations (15.625, 31.25, 62.5, 125, 250, 500, 1000, and 2000 mg/L) of N- and S-CDs@AgMOFs nanocomposites during 48 h. The results showed the bactericidal effect of N- and S-CDs@AgMOFs on Bacillus subtillis and the antifungal effect on Candida albicans. The effect of S-CDs@AgMOFs was stronger on bacterial cells compared to the N-CDs@AgMOFs, while both agents affected fungi in equal concentrations, indicating different mechanisms in the two types of microorganisms. In Candida albicans, minimal inhibitory concentration (MIK) of both nanocomposites was 125 mg/L, while in Bacillus subtilis MIK of N-CDs@AgMOFs was 500 mg/L and for S-CDs@AgMOFs was 250 mg/L. It can be concluded that tested nanocomposites are safe for the environment because they are not toxic in the concentrations in which they can be found in the environment

Oleic acid variation and marker-assisted detection of Pervenets mutation in high- and low-oleic sunflower cross

High-oleic sunflower oil is in high demand on the market due to its heart-healthy properties and richness in monounsaturated fatty acids that makes it more stable in processing than standard sunflower oil. Consequently, one of sunflower breeder's tasks is to develop stable high-oleic sunflower genotypes that will produce high quality oil. We analyzed variability and inheritance of oleic acid content (OAC) in sunflower, developed at the Institute of Field and Vegetable Crops, by analyzing F-1 and F-2 progeny obtained by crossing a standard linoleic and high-oleic inbred line. F-2 individuals were classified in two groups: low-oleic with OAC of 15.24-31.28% and high-oleic with OAC of 62.49-93.82%. Monogenic dominant inheritance was observed. Additionally, several molecular markers were tested for the use in marker-assisted selection in order to shorten the period of detecting high-oleic genotypes. Marker F4-R1 was proven to be the most efficient in detection of genotypes with Pervenets (high-oleic acid) mutation

New substituted 2-methylthiomethyl- and 2-methylsulphinylmethylenebenz- imidazoles with D 2 /5-HT(1A) activity

Several 2-methylthiomethylbenzimidazoles (3a-e) and the corresponding sulphinyl derivatives 4a-e were synthesized and evaluated measuring their in vitro binding affinity at the D 1 and D 2 dopamine (source: synaptosomal membranes of the bovine nucleus caudatus) and 5-HT(1A) serotonin (source: synaptosomal membranes of the bovine hippocampus) receptors. [ 3 H]SCH 23390, [ 3 H]spiperone, and [ 3 H]-8-OH-DPAT were employed as specific radioligands for the D 1 , D 2 and 5-HT(1A) receptors, respectively. None of the compounds except for 3b acting as a moderate [ 3 H]SCH 23390, competitor, expressed binding affinity at the D 1 receptor. Compounds 4a and 4e were inactive displacers of both [ 3 H]spiperone and [ 3 H]-8-OH-DPAT. Ligands 4b, 3d and 4d acted as weak to moderate [ 3 H]spiperone competitors and 3a was a weak [ 3 H]- 8-OH-DPAT displacer. The remaining ligands expressed binding affinity at the corresponding receptors in a nanomolar concentration range. Among them, compound 3b with K(i) of 14.2 nM and 8.4 nM in [ 3 H]spiperone and [ 3 H]-8- OH-DPAT binding assay, respectively, was the most potent mixed dopaminergic/serotonergic ligand. Although sterically similar, the two classes of ligands differ with regard to electronic properties of substituents in position 2 of the benzimidazole ring. Oxidation of 2- (methylthiomethyl)benzimidazoles afforded ligands devoid of binding affinity at the 5-HT(1A) receptor and significantly reduced binding affinity at the D 2 receptor. This points to the importance of electronic properties of substituents in position 2 of benzimidazole ring for the D 2 /5-HT(1A) affinity ratio of this type of ligands

Novel 5-[2-(N,N-di-n-propylamino)-ethyl]benzimidazole-derived high affinity dopaminergic ligands

Derivatives of a noncatechol dopamine (DA) bioisostere 5-[2-(N,N-di-n-propylamino)ethyl]-benzimidazole (15) were synthesized and checked for affinity towards D-1 and D-2 DA receptors (DAR). Ten compounds were obtained by introducing groups of different inductive effects into position 2 of the parent compound 15, while two other compounds were synthesized by introducing a 1-naphthyl group into the side chain of dichloromethyl (9) and dibromomethyl (10) derivatives of 15. The affinity and selectivity of these novel compounds for the D-1 and D-2 class of the DAR were estimated by in vitro competition binding assays using synaptosomal membranes of the bovine caudate nuclei and [ 3 H]SCH 23390 (D-1 selective) and [ 3 H]spiperone (D-2 selective) as radioligands. None of the synthesized compounds expressed the affinity for the binding to D-1 receptors, while compounds 13, 14, 10, 9, 7 and 8, in this rank order of potencies competed with [ 3 H]spiperone binding to D-2 receptors under conditions of prevented radioligand binding to serotonin 5HT 2 receptors. Their affinities for this class of the DAR were about 2- to 555-fold higher in comparison to the parent compound 15, thus suggesting that some of them could be successfully used as dopaminergic ligands

New substituted 2-methylthiomethyl- and 2-methylsulphinylmethylenebenz- imidazoles with D 2 /5-HT(1A) activity

Several 2-methylthiomethylbenzimidazoles (3a-e) and the corresponding sulphinyl derivatives 4a-e were synthesized and evaluated measuring their in vitro binding affinity at the D 1 and D 2 dopamine (source: synaptosomal membranes of the bovine nucleus caudatus) and 5-HT(1A) serotonin (source: synaptosomal membranes of the bovine hippocampus) receptors. [ 3 H]SCH 23390, [ 3 H]spiperone, and [ 3 H]-8-OH-DPAT were employed as specific radioligands for the D 1 , D 2 and 5-HT(1A) receptors, respectively. None of the compounds except for 3b acting as a moderate [ 3 H]SCH 23390, competitor, expressed binding affinity at the D 1 receptor. Compounds 4a and 4e were inactive displacers of both [ 3 H]spiperone and [ 3 H]-8-OH-DPAT. Ligands 4b, 3d and 4d acted as weak to moderate [ 3 H]spiperone competitors and 3a was a weak [ 3 H]- 8-OH-DPAT displacer. The remaining ligands expressed binding affinity at the corresponding receptors in a nanomolar concentration range. Among them, compound 3b with K(i) of 14.2 nM and 8.4 nM in [ 3 H]spiperone and [ 3 H]-8- OH-DPAT binding assay, respectively, was the most potent mixed dopaminergic/serotonergic ligand. Although sterically similar, the two classes of ligands differ with regard to electronic properties of substituents in position 2 of the benzimidazole ring. Oxidation of 2- (methylthiomethyl)benzimidazoles afforded ligands devoid of binding affinity at the 5-HT(1A) receptor and significantly reduced binding affinity at the D 2 receptor. This points to the importance of electronic properties of substituents in position 2 of benzimidazole ring for the D 2 /5-HT(1A) affinity ratio of this type of ligands