The crystal structure and the biological activity of a new coordination compound of magnesium ions with comenic acid, magnesium comenate, was characterized and studied. Quantitative and qualitative analysis of the compound was investigated in detail using elemental X-ray fluorescent analysis, thermal analysis, IR-Fourier spectrometry, UV spectroscopy, NMR spectroscopy, and X-ray diffraction analysis. Based on experimental analytical data, the empirical formula of magnesium comenate [Mg(HCom)₂(H₂O)₆]·2H₂O was established. This complex compound crystallizes with eight water molecules, six of which are the hydration shell of the Mg²⁺ cation, and two more molecules bind the [Mg(H₂O)₆]²⁺ aquacation with ionized ligand molecules by intermolecular hydrogen bonds. The packing of molecules in the crystal lattice is stabilized by a branched system of hydrogen bonds with the participation of solvate water molecules and oxygen atoms of various functional groups of ionized ligand molecules. With regard to the biological activity of magnesium comenate, a neuroprotective, stress-protective, and antioxidant effect was established in in vitro and in vivo models. In in vitro experiments, magnesium comenate protected cerebellar neurons from the toxic effects of glutamate and contributed to the preservation of neurite growth parameters under oxidative stress caused by hydrogen peroxide. In animal studies, magnesium comenate had a stress-protective and antioxidant effect in models of immobilization–cold stress. Oral administration of magnesium comenate at a dose of 2 mg/kg of animal body weight for 3 days before stress exposure and for 3 days during the stress period led to a decrease in oxidative damage and normalization of the antioxidant system of brain tissues against the background of induced stress. The obtained results indicate the advisability of further studies of magnesium comenate as a compound potentially applicable in medicine for the pharmacological correction of conditions associated with oxidative and excitotoxic damage to nerve cells.

The possibility of establishing the varietal and territorial affiliation of wines by the content of rare earth elements (REE) in them was studied. ICP–OES and ICP–MS with subsequent chemometric processing of the results were applied to determine the elemental image of soils containing negligible REE amounts, grapes grown on these soils, and wine materials of Cabernet Sauvignon, Merlot, and Moldova varieties produced from these grapes. To stabilize and clarify wine materials, the traditional processing of wine materials with various types of bentonite clays (BT) was used, which turned out to be a source of REE in the wine material. Discriminant analysis revealed that the processed wine materials were homogeneous within one denomination and that those of different denominations were heterogeneous with respect to the content of REE. It was found that REE in wine materials were transferred from BT during the processing, and thus they can poorly characterize the geographical origin and varietal affiliation of wines. Analysis of these wine materials according to the intrinsic concentrations of macro- and microelements showed that they formed clusters according to their varietal affiliation. In terms of their influence on the varietal image of wine materials, REE are significantly inferior to macro- and microelements, but they enhance their influence to a certain extent when used together.

The features for assessing the authenticity of wines by region of origin are studied, based on the relationship between the mineral composition of the wine, the grapes, and the soil profile (0 to 160 cm) from the place of growth of Cabernet Sauvignon grapes. Soil, grape, and wine samples were taken from the territories of six vineyards in the Anapa district of Krasnodar Territory, Russia. Using the methods of ICP-OES, thermal, and X-ray phase analysis, the soils were differentiated into three groups, differing in mineralogical and mineral compositions. The soil samples of the first group contained up to 31% quartz, the second group up to 25% quartz and 19% mixed calcite, and the third group up to 32% calcite and 15% quartz. The formation of the elemental image of the grapes was studied, taking into account the total content and mobile forms of metals in the soil. The territorial proximity of the vineyards did not affect the extraction of elements from the soil into the grape berry, and the migration of metals for each territory was selective. According to the values of the biological absorption coefficient, the degree of transition of metals from the soil to a berry was estimated. For K, Ti, Zn, Rb, Cu, and Fe in all berries, the coefficient was higher than 1.00, which means that the berry extracts contained not only mobile-form, but also difficult-to-dissolve metal compounds. The migration of macro-components from the soil to the berry was low, and amounted to 6–7% for Ca, 0.8–3.0% for Na, and 25–70% for Mg of the concentration of their mobile forms. For all territories, the maximum correlation between metal concentrations in grapes and soil was observed for samples from a depth of 0–40 cm. The discriminant model based on concentrations of Rb, Al, K, Sr, Co, Na, Pb, Ca, and Ni showed the formation of clusters in the territories of vineyard cultivation. The developed model allow the problems of identifying wines by region to be solved with high accuracy, using their elemental image.

The aim of this work is to study the correlations of the elemental composition in the “soil–grape–wine” chain to determine the regional origin of Chardonnay grapes and wine. Soil samples (n = 40) from five vineyards in the Anapa region, Russia, taken from eight different depths, grapes from these vineyards (n = 75), and wines obtained from these grapes (n = 5) were analyzed using inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry. The mineralogical composition of the soils was determined using thermal and X-ray phase analysis. The mineralogical composition of vineyard soils mainly consists of calcite, quartz, nontronite, vermiculite, and muscovite. According to spectrometric analysis, the distribution of both the total content and the mobile forms of elements in soil profiles turned out to be similar. The content of Na, Ca, and Sr increased with increasing sampling depth, while the content of Co, Cu, Fe, Ni, Mn, Pb, and Zn decreased. Regardless of the area of cultivation, the predominant elements in grapes are K, Ca, Na, and Mg. It is established that the elemental profiles of grapes and wine are correlated. At the same time, during the winemaking process, a decrease in the concentration of most elements (Al, Ba, Ca, Cu, K, Mg, Mn, Ni, Rb, Sr, Ti, and Zn) is observed. It has been shown that the vine is able to accumulate not only mobile but also less bioavailable forms of metals from the soil (Cu, Fe, K, Rb, Ti, and Zn), while the migration of Ca and Na remains low (<7%). Using discriminant analysis, a model of grape identification based on the concentrations of Al, Li, Mn, Na, Pb, and Rb was developed. This model demonstrated a high accuracy (100% for training and test datasets) in grape classification by region, confirming that the elemental “fingerprint” is a reliable marker of terroir.

The work is devoted to the peculiarities of chlorine and lead determination in dust emissions of gas cleaning vents of electric steelmaking by energy-dispersive X-ray fluorescence analysis (EDXRF). A technique has been developed for the express energy-dispersive X-ray fluorescence determination of chlorine and lead in dust emissions of gas cleaning vents using powder model mixtures as standard samples similar in composition to real samples of dust emissions of gas cleaning vents. The analytes were determined using the characteristic ClKα1,2 and PbLα1,2 radiation lines. The possibility of reducing interfering effects of braking and characteristic radiation from the X-ray tube with an aluminum filter in the determination of chlorine, achieved by increasing the signal to background ratio for characteristic ClKα1,2 radiation line, is considered. The uncertainty of EDXRF method for determining chlorine and lead in dust emissions of gas cleaning vents was estimated using additional model mixtures. The calculation of accuracy indicators, repeatability limits, and intra-laboratory precision was carried out for energy-dispersive X-ray fluorescence determination of chlorine and lead in dust emissions of gas cleaning vents according to the obtained equations. It was shown that the results for chlorine determination in samples were overestimated (up to 7.7 %) relative to the accepted reference value if no filter was used, and were underestimated (up to 4.4 %) when the filter was present. For lead, the maximum deviation from the accepted reference value was 10.6 %. Constructed calibration graphs and pelleted model samples are stable for several months. Satisfactory consistency of the results of energy-dispersive X-ray fluorescence determination of chlorine and lead with data from standardized methods for analyzing real samples of dust emissions of gas cleaning vents was obtained; standard deviations did not exceed 13 % for lead and 11 % for chlorine. The proposed EDXRF method for the determination of lead and chlorine in dust emissions of gas cleaning vents is more efficient and less laborious.