Health risk assessment of heavy metals in soil, plant, and water samples near "Gacko" power plant, in Bosnia and Herzegovina.

This study assesses heavy metal content in soil, water, and plant material from sites located around the lignite mine and the power plant "Gacko", Bosnia and Herzegovina. The samples were collected, prepared, and analyzed for heavy metals content using the flame atomic absorption spectrophotometer. Samples were analyzed for cadmium, lead, copper, zinc, manganese, and iron. To identify the relationship among the metals in samples and their possible sources, Pearson's correlation and principal component analysis were performed. Health risk assessment was applied to establish potential health risks posed to humans caused by contaminants in different environmental compartments. The results of our analyses show that most soil samples contain copper, and one of those samples had a copper concentration of more than 70 µg/g, which is a critical upper value for agricultural use. In the soil samples that were analyzed, cadmium was also detected, and its concentration was greater than 2 µg/g. Lead, on the other hand, had a concentration that was higher than the maximum permissible for unpolluted soils in 40% of the soil samples that were analyzed. Lead and cadmium concentrations in surface waters mostly contribute to a non-carcinogenic risk in the scenario of recreational swimming exposure. The presence of Cd, a highly toxic element in water, may be explained by the leaching of artificial fertilizers used in the study area, whereas Pb's origin may be geological. The results of this study recommend routine heavy metal monitoring in samples of soil, water, and plants from the examined area so that, if metal concentrations continue increasing, remedial action should be advised to prevent accumulation in the food chain.

Lignin and organic free radicals in maize (Zea mays L.) seeds in response to aflatoxin B1 contamination: an optical and EPR spectroscopic study.

BACKGROUND: Aflatoxin B1 (AFB1 ) is the most dangerous of the mycotoxins that contaminate cereal seeds naturally. A stress lignin formation is linked with the accumulation of reactive oxygen species causing a change in the redox status and formation of stable organic radicals, constituting the first layer of defense. The relationship between AFB1 and changes in lignin organic free radicals in seeds is not known, nor is the part of the seed that is more targeted. Using optical and electron paramagnetic resonance spectroscopy, we investigated AFB1 -induced changes in lignin and organic free radicals in seeds, and whether the inner and outer seed fractions differ in response to increasing AFB1 . RESULTS: Different changes in the content of lignin and free radicals with increasing AFB1 concentrations were observed in the two seed fractions. There was a significant positive linear correlation (R = 0.9923, P = 0.00005) between lignin content and AFB1 concentration in the outer fraction, and no correlation between the lignin content and the AFB1 concentration in the inner fraction. We found a positive correlation between the area of the green spectral emission component (C4) and the AFB1 concentration in the outer fraction. CONCLUSIONS: To the best of our knowledge, the results showed, for the first time, that maize seed fractions respond differently to aflatoxin with regard to their lignin and organic free radical content. Lignin content and (C4) area may be reliable indicators for the screening of lignin changes against AFB1 content in the seeds, and thus for seed protection capacity. © 2021 Society of Chemical Industry.

Variations in polyamine conjugates in maize (Zea mays L.) seeds contaminated with aflatoxin B1: a dose-response relationship.

BACKGROUND: Cereal seeds, such as maize seeds, are frequently contaminated with aflatoxin B1 (AFB1), one of the most dangerous naturally occurring carcinogens. In plants, phenolamides are involved in biotic stress response. The data on variations of phenolamides in AFB1-containing seeds are limited. RESULTS: Five polyamine conjugates, including two spermidine and three putrescine conjugates, were tentatively identified in methanolic extracts, using HPLC-DAD-MS. The ratio of putrescine to spermidine conjugates changed with increasing AFB1 concentration in a logistic dose-response manner, with a ratio of below 1 up to a concentration of 51.51 µg kg-1 , and approximately 2.54 and 3 at higher concentrations of 177.4 and 308.13 µg kg-1 , respectively. The observed variations of the total antioxidant activity and the total phenolic content may support this biphasic behaviour of the seeds against AFB1 stress. CONCLUSIONS: The obtained data are a contribution to the understanding of the roles of polyamine conjugates in seed defence to increasing AFB1 concentrations. According to our knowledge, this study reports for the first time the biphasic response of maize seeds to increasing AFB1 contamination level, comprising the induction of polyamine conjugate accumulation and variation in the ratio of conjugates. This dose-response relationship may provide useful information in the field of agricultural and food chemistry as an indicator of AFB1 contamination level and, hence, for selecting an appropriate seed quality. © 2020 Society of Chemical Industry.

Effect of substituents on prediction of TLC retention of tetra-dentate Schiff bases and their Copper(II) and Nickel(II) complexes.

The objectives of this study were to gain insights into structure-retention relationships and to propose the model to estimating their retention. Chromatographic investigation of series of 36 Schiff bases and their copper(II) and nickel(II) complexes was performed under both normal- and reverse-phase conditions. Chemical structures of the compounds were characterized by molecular descriptors which are calculated from the structure and related to the chromatographic retention parameters by multiple linear regression analysis. Effects of chelation on retention parameters of investigated compounds, under normal- and reverse-phase chromatographic conditions, were analyzed by principal component analysis, quantitative structure-retention relationship and quantitative structure-activity relationship models were developed on the basis of theoretical molecular descriptors, calculated exclusively from molecular structure, and parameters of retention and lipophilicity.

In vitro and in silico study of the biological activity of tetradentate Schiff base copper(II) complexes with ethylenediamine-bridge.

The biological activity of six structurally similar tetradentate Schiff base copper(II) complexes, namely [Cu(ethylenediamine-bis-acetylacetonate)] (CuAA) and five derivatives where two methyl groups are replaced by phenyl, (CuPP), CF3 (CuTT) or by mixed groups CH3/CF3 (CuAT), Ph/CF3 (CuPT), and Ph/CH3 (CuAP) has been investigated. The set of antioxidant assays was performed, and the results were expressed as IC50 and EC50 values. The series of complexes showed interesting bioactivity and were investigated for the determination of antioxidant, antifungal, antimicrobial, and cytotoxic activity. A significant antioxidant behavior was exhibited by complex CuAA, greater than Trolox in the Oxygen Radical Absorbance Capacity (ORAC) assay. Antibacterial assay over Gram-positive and Gram-negative pathogenic bacterial strains and some fungal pathogens were studied. Antiproliferative activity of complexes in two human tumor cell lines, breast adenocarcinoma MCF-7, colon adenocarcinoma LS-174, and normal fibroblast cells-MRC-5, examined the effect on cell cycle progression. The significant cytotoxic potential, comparable to cisplatin cytotoxicity, was determined in human breast cancer cell line-MCF-7 with IC50 values being 17.53-31.40 µM and human colon cancer cell line-LS-174 with IC50 values being 15.22-23.92 µM. All tested compounds showed nearly twice more selectivity toward cancer cell lines than normal cells. The interactions of complexes with human serum albumin (HSA), the most prominent protein in plasma, were investigated using spectroscopic fluorescence techniques. The complexes bind to human serum albumin at multiple sites (n = 0.2-1.9), displaying a moderate binding constant Ka = 4.1-12.4 × 104 M-1. The molecular docking experiment effectively showed complex binding to HSA and DNA molecular fragments.

Synthesis, characterization, biomolecular interactions, molecular docking, and in vitro and in vivo anticancer activities of novel ruthenium(III) Schiff base complexes.

In order to discover new anticancer drugs, novel ruthenium(III) complexes [Ru(L)Cl(H2O)], where L is tetradentate Schiff base bis(acetylacetone)ethylendiimine (acacen, 1), bis(benzoylacetone)ethylendiimine (bzacen, 2), (acetylacetone)(benzoylaceton)ethylendiimine (acacbzacen, 3), bis(acetylacetone)propylendiimine (acacpn, 4), bis(benzoylacetone)propylendiimine (bzacpn, 5) or (acetylacetone)(benzoylaceton)propylendiimine (acacbzacpn, 6), were synthesized. The complexes 1 - 6 were characterized by elemental analysis, molar conductometry, and by various spectroscopic techniques, such as UV-Vis, IR, EPR, and ESI-MS. Based on in vitro DNA/BSA experiments, complexes 2 (bzacen) and 5 (bzacpn) with two aromatic rings showed the highest DNA/BSA-activity, suggesting that the presence of the aromatic ring on the tetradentate Schiff base ligand contributes to increased activity. Moreover, these two compounds showed the highest cytotoxic effects toward human, A549 and murine LLC1 lung cancer cells. These complexes altered the ratio of anti- and pro-apoptotic molecules and induced apoptosis of A549 cells. Further, complexes 2 and 5 reduced the percentage of Mcl1 and Bcl2 expressing LLC1 cells, induced their apoptotic death and exerted an antiproliferative effect against LLC1. Finally, complex 5 reduced the volume of mouse primary heterotopic Lewis lung cancer, while complex 2 reduced the incidence and mean number of metastases per lung. Additionally, molecular docking with DNA revealed that the reduced number of aromatic rings or their absence causes lower intercalative properties of the complexes in order: 2 > 5 > 6 > 3 > 4 > 1. It was observed that conventional hydrogen bonds and hydrophobic interactions contribute to the stabilization of the structures of complex-DNA. A molecular docking study with BSA revealed a predominance of 1 - 6 in binding affinity to the active site III, a third D-shaped hydrophobic pocket within subdomain IB.

Polyphenolic and Chemical Profiles of Honey From the Tara Mountain in Serbia.

This study presents a detailed characterization of 27 honey samples from the Tara Mountain region in Serbia using different comprehensive techniques and methods. The types of the honey samples were defined as monofloral (4 samples), honeydew (5 samples) and polyfloral (18 samples) honey based on determined polyphenol content, antioxidant activity, electrical conductivity and melissopalynological analyses. Physicochemical parameters such as pH (4.13-4.94), diastase activity (24.20-41.70 DN), acidity (14.60-29.70 meq/kg), content of 5-(hydroxymethyl)furfural (in range below 5, up to 16.90 mg/kg), sucrose (0.20-3.90 g/100 g), and moisture content (15.01-19.23%) confirmed the required quality of the honey samples. Sensory analysis revealed honey characteristics favorable to consumers. Analyses of 19 phenolic compounds using ultra-high-performance liquid chromatography with a diode-array detection and triple quadrupole mass spectrometry (UHPLC-DAD-MS/MS) revealed six phenolic acids and 13 other compounds from the group of flavonoids and their glycosides. In all the samples the highest content was determined for p-coumaric acid, followed by caffeic acid and pinocembrin. Besides total phenolic content and radical scavenging activity, antimicrobial activity was also examined. Most honey samples showed bactericidal activity against Staphylococcus aureus and bacteriostatic activity against Escherichia coli, while none of the honey samples inhibited the growth of Candida albicans. Chemometric analyses were applied for an in-depth study of the results to further evaluate the characteristics of the honey samples studied. Principal component analysis (PCA) was used for assessing the differences in physicochemical parameters, polyphenols content and antioxidant capacity between honey samples. The unrooted cluster tree was used to group the samples based on the melissopalynological analyses.

Voltammetric Determination of Lead and Copper in Wine by Modified Glassy Carbon Electrode.

This paper describes the determination of Pb and Cu with a Nafion-modified glassy carbon electrode and MnCo2O4 nanoparticles as working electrode for anodic stripping voltammetry. Pb and Cu were accumulated in HCl/KCl (0.1 mol dm-3) at a potential of -1.4 V (vs. Ag/AgCl electrode) for 480 s, followed by a linear sweep anodic stripping voltammetry (ASV) scan from -1.0 to +0.5 V. Under optimum conditions, the calibration curves were linear in the range of 0.01 - 8 and 0.01 - 5 mg dm-3 for Pb and Cu, respectively. Effect of sample dilution, accumulation time and potential were optimized. A study of interfering substances was performed. A significant increase in current was obtained at the modified electrode in comparison with the bare glassy carbon electrode. The modified electrode was successfully applied for determination of Pb and Cu in wine samples after a simple preparation procedure. Pb and Cu content in wine was used for estimation of the target hazard quotient (THQ) values for minimal and maximal levels of the metals.

Elemental Analysis and Phenolic Profiles of Selected Italian Wines.

The study of the chemical composition of wines is nowadays a topic of great interest because of the importance of this market, especially in Italy, and also considering the numerous cases of falsification of famous and very expensive wines. The present paper focused on the analysis of metals and polyphenols in Italian wines belonging to different provenance and types. At this purpose 20 elements were quantified by inductively coupled plasma optical emission spectrometry (ICP-OES) and ICP mass spectrometry (ICP-MS). Regarding polyphenols, a total of 32 were quantified, among 6 were anthocyanins. Furthermore, in 4 samples (1 rosè and 3 red wines) 42 anthocyanins and related compounds were identified by ultra-high performance liquid chromatography (UHPLC)-Orbitrap MS technique (among these, 6 were also quantified). Non-anthocyanins were determined using UHPLC coupled with a diode array detector and triple-quadrupole mass spectrometer (UHPLC-DAD-QqQ-MS). Total phenolic content (TPC) and radical scavenging activity (RSA) were measured using spectrophotometric methods. The results obtained by elemental techniques were submitted to principal components analysis (PCA) allowing to get information on both geographical and botanical origin of the examined wine samples. Some polyphenols have been detected in higher concentrations only in a certain type of wine, as for example in the case of Grechetto wine. Most of the identified anthocyanin derivatives (pyranoanthocyanins) are formed during the aging of wine by reaction with the other wine components.

Physicochemical analysis and phenolic profile of polyfloral and honeydew honey from Montenegro.

The research subject of this paper was a detail physicochemical analysis of 28 honey samples from the northern part of Montenegro. The honey from Montenegro has not been previously studied in such detail. Differentiation between samples, such as honeydew honey and polyfloral honey, was based on electrical conductivity, which was higher than 0.8 mS cm-1 for honeydew honey, as was expected. Other investigated physicochemical parameters (water content, free acids, diastase activity, hydroxymethylfurfural (HMF) content and sugar content) have shown great similarity for all honey samples. The main interest of this study was the identification and quantification of phenolic compounds using ultra-high performance liquid chromatography (UHPLC) with mass spectrometry detection. The results show that honey samples are very rich in phenolic compounds, especially quercetin. Among the 31 quantified phenolic compounds, the most dominant were phenolic acids. The highlight was based on p-hydroxybenzoic acid, p-coumaric acid, caffeic acid and ferulic acid. Considering polyphenolic compounds and sugar content, a high nutritional value can be observed in all samples, with an emphasis on polyfloral honeys, as was confirmed with principal component analysis (PCA). In addition, all honey samples were tested for total phenolic content (TPC) and radical scavenging activity (RSA). The results indicate the higher antioxidant ability of honeys from Montenegro in comparison to some honey samples from other countries in the region.

Synthesis of MnCo2O4 nanoparticles as modifiers for simultaneous determination of Pb(II) and Cd(II).

The porous spinel oxide nanoparticles, MnCo2O4, were synthesized by citrate gel combustion technique. Morphology, crystallinity and Co/Mn content of modified electrode was characterized and determined by Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction pattern analysis (XRD), simultaneous thermogravimetry and differential thermal analysis (TG/DTA). Nanoparticles were used for modification of glassy carbon electrode (GCE) and new sensor was applied for simultaneous determination of Pb(II) and Cd(II) ions in water samples with the linear sweep anodic stripping voltammetry (LSASV).The factors such as pH, deposition potential and deposition time are optimized. Under optimal conditions the wide linear concentration range from 0.05 to 40 µmol/dm3was obtained for Pb(II), with limit of detection (LOD) of 8.06 nmol/dm3 and two linear concentration ranges were obtained for Cd(II), from 0.05 to 1.6 µmol/dm3 and from 1.6 to 40 µmol/dm3, with calculated LOD of 7.02 nmol/dm3. The selectivity of the new sensor was investigated in the presence of interfering ions. The sensor is stable and it gave reproducible results. The new sensor was succesfully applied on determination of heavy metals in natural waters.

Development of a Flow Injection System for Differential Pulse Amperometry and Its Application for Diazepam Determination.

This work presents the development of a flow injection system for differential pulse amperometry (DPA) for diazepam determination in the presence of oxygen. The thin flow cell consisted of the bare glassy carbon electrode, reference silver/silver chloride, and stainless steel as the auxiliary electrode. Electrochemical reduction of diazepam (DZP) was characterised by cyclic voltammetry. Azomethine reduction peak was used for DZP quantification. The detector response was linear in the range 20-250 µmol/dm3 of diazepam, with a calculated detection limit of 3.83 µg/cm3. Intraday and interday precision were 1.53 and 10.8%, respectively. The method was applied on three beverage samples, energetic drink, and two different beer samples, and obtained recoveries were from 93.65 up to 104.96%. The throughoutput of the method was up to 90 analyses per hour.

Physicochemical, antioxidant and sensory properties of peach wine made from redhaven cultivar.

Physicochemical, sensory, and health-related characteristics of peach wine produced from Redhaven variety and selected white wines produced from various grape varieties were determined and compared. The alcohol content, titratable acidity, and total extract of peach wine was significantly lower compared with that of white wines, while its pH value was higher. The content of total phenolics (TPC) and flavonoids (TFC) of peach wine (402.53 mg/L GAE and 332.67 mg CAE/L, respectively) have been found significantly higher in comparison with that of white wines (TPC range 243.67-319.00 mg/L GAE, TFC range 129.67-175.17 mg CAE/L). The main phenolic compounds found in peach wine were chlorogenic acid, caffeic acid, and catechin (3.59, 0.87, and 0.60 mg/L, respectively). Antioxidant capacities were strongly correlated with total phenolics with correlation coefficients over 0.99. The highest antioxidant capacity was ascribed to peach wine. The results of sensory analysis indicated that the peach wine was very well accepted by the regular consumers of wine and can be a very interesting product in the market.

Relationships between structure, retention and biological activity of some Schiff base ligands and their complexes.

The lipophilicity of a series of Schiff base ligands and their complexes with nickel(II) and copper(II) has been determined by reversed-phase thin-layer chromatography using binary dioxane-water mobile phase. Chelate ligands were prepared by condensation of diamine and the corresponding beta-diketone. Copper(II) and nickel(II) complexes with chelate ligands containing ethane-1,2-diamine or propane-1,2-diamine as the amine part and pentane-2,4-dione and/or 1-phenylbutane-1,3-dione, pentane-2,4-dione and/or 1,1,1-trifluoropentane-2,4-dione, or 1,1,1-trifluoropentane-2,4-dione and/or 1-phenylbutane-1,3-dione as the beta-diketone part were synthesized. Some of investigated compounds were screened for their in vitro antifungal activity against Sacharomyces cerevisiae and antibacterial activity against Escherichia coli. Chromatographically obtained lipophilicity parameters were correlated both with calculated n-octanol-water partition coefficient C log P and antimicrobial activities. Satisfactory correlations were obtained. Chromatographic data proved to be reliable parameters for describing the lipophilic properties of the investigated compounds. Additionally, the principal components analysis was performed on the data chromatographically obtained. This statistical method was useful for distinguishing compounds and objective comparison of their lipophilicity parameters.