Vol 24, No 1 (2024)
Chemistry
Selective mycotoxines sorbent based on molecular imprinted polyaniline structures
Abstract
The constant increase in contamination of agricultural products with mycotoxins makes it urgent to develop new methods for their sorption, isolation, and determination. Molecular imprinting is a promising method for recognizing and isolating target molecules based on specifi c sorption mechanism. The work considers the possibility of obtaining and practical use of mycotoxin–specifi c selective sorbents based on imprinted polyaniline structures using a structural analogue of the mycotoxin zearalenone – 4-hydroxycoumarin. The optimal carrier for the synthesis of molecularly imprinted polymers has been selected. The specifi city of 4-hydroxycoumarin sorption from model solutions has been studied. The practical possibility of sorption and extraction of ZEA from an artifi cially contaminated wheat extract has been demonstrated.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):4-14
4-14
Dependence of physical-chemical properties of fluorescent hybrid polymer carriers on the conditions of hydrothermal synthesis
Abstract
Currently, the search for new types of carriers for low-molecular weight substances, as well as the development of optimal methods for the eff ective encapsulation of these substances are important tasks of modern chemistry and pharmacology. However, there are still limitations in this area, among which one of the most signifi cant is the lack of the optimal carrier capable of stably retaining a low-molecular weight substance. The work presents hybrid polymer structures obtained by in situ hydrothermal synthesis as an eff ective candidate for these purposes. The fl uorescent dye rhodamine B has been used as a model low-molecular weight substance for encapsulation into the structures. The resulting hybrid polymer structures demonstrated good stability when stored in an aqueous environment for 336 h with the release of the low-molecular weight dye rhodamine B no more than 2%. In addition, the infl uence of the conditions for obtaining hybrid carriers (including the composition of the carriers (thickness of the polymer shell and the presence of a calcium carbonate core) and synthesis temperature) on their physical-chemical characteristics has been studied. Thus, the optimal approach for obtaining fl uorescent hybrid polymer carriers with a set of desired properties has been revealed. In particular, it has been shown that the optimal production conditions are hydrothermal synthesis temperature of 180 °C and the absence of CaCO3 core inside the polyelectrolyte shell which allow us to obtain a stable hybrid polymer carrier with bright fl uorescence. The results presented in this study can be used to create functional platforms and systems with tunable fl uorescent properties and the ability to deliver low-molecular weight substances.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):15-27
15-27
Phase behavior and solubility of components of the binary butyric acid – polyethylene glycol-1500 system
Abstract
A critical review of the literature on the methods of concentration and extraction of biobutyric acid from fermentation solutions has been carried out. The best results of these processes are achieved by combining extraction with salting. It is proposed to use polyethylene glycols with diff erent molecular weights as non-fl ammable and environmentally friendly extractants. The purpose of the study was to identify the phase behavior of mixtures of components, study solubility and construct a phase diagram of the previously unexplored double system butyric acid – PEG-1500 in the range −10.0–50.0°C. The transition temperatures of phase states in mixtures of components of the dual system butyric acid (BA) – polyethylene glycol-1500 (PEG-1500) in the temperature range −10–50°C have been found by the visual-polythermal method. The phase diagram above the eutectic line shows a large crystallization fi eld of PEG-1500, while the crystallization fi eld of BA has very small dimensions. It has been established for the fi rst time that eutectic equilibrium is carried out in the system at −6.6°C, the solid phases of which are crystals of BA and PEG-1500, the composition of the liquid phase of eutectic (3.20 wt.% BA) has been determined. A method for concentrating BA and separating the components of the investigated system based on the crystallization of PEG-1500 during cooling of mixtures is proposed.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):28-34
28-34
Heterophase phenomena of tritium fractionation in water systems
Abstract
Tritium is the only one of the radioactive isotopes that a filtering system is unable to neutralize. It is produced by collateral fi ssion processes in nuclear reactors and displays itself in radioactive wastes and effl uents in diff erent forms of tritium oxides. Thus the development and application of nuclear energy entails a challenging problem of treating tritium-containing radioactive wastewater.The paper deals with tritium water isotopologues, namely, with prototritium water and deuterotritium water. Various approaches to the problem of tritium separation have been outlined. The choice of the appropriate process of water detritiation depends, fi rst of all, on whether the detritiated water is recycled back to the reactor system or is discharged to the environment and on whether molecular tritium is to be extracted for further application. Special attention is paid to the process of electrosonochemical water detritiation which is shown to be the preferential one due to its ability to provide molecular tritium. Tritiated water decomposition should be preceded by its concentrating, the latter being two-stage and including water conditioning followed by providing concentrated tritiated water. Reverse-osmosis conditioning and salt rectifi cation are considered as preferential techniques.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):35-43
35-43
Changes in the chemical, physical-chemical and biological properties of Ochrobactrum cytisi IPA7.2 lipopolysaccharide during О-deacylation
Abstract
Lipopolysaccharides are compounds of bacterial origin that have biological activity against plants, animals and humans. This work provides information on the preparation and characterization of the properties of modifi ed lipopolysaccharide derivatives of the rhizosphere bacterium Ochrobactrum cytisi IPA7.2. Deacylation has been carried out using alkaline hydrolysis, followed by chromatographic separation of the fractions. O-deacetylation of O-polysaccharide led to a 2-fold increase in the extinction of the products of the phenol-sulfuric acid reaction. The fatty acid composition of lipid A did not change during alkaline hydrolysis. A comparison of supramolecular particles in an aqueous medium of native and deacylated forms of lipopolysaccharide using dynamic light scattering revealed that, as a result of modifi cation, the size of micelles decreased from 65 nm to 35 nm and their negative zeta potential increased from –22 mV to –30 mV. It has been found that non-stoichiometric acetylation of lipopolysaccharide O. cytisi IPA7.2 did not aff ect the interaction with specifi c antibodies but was important for the manifestation of growth-stimulating activity towards potato microplants.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):44-50
44-50
Biology
Proposals for improving a non-invasive method for estimating abundance of mouse-like rodents and shrews in urban areas
Abstract
Previously we proposed a new reconnaissance method for estimating the total abundance of small mammals in urban areas. The method includes placing plastic bottles with bait inside equal distances apart. In this research we examined two ways to improve the method: using bottles of smaller volume (0,25 liters instead of 0,5 liters) to increase the ergonomics and using opaque bottles to make them more attractive for animals. Bigger and smaller bottles with neck diameter of 38 mm were fastened in pairs which were set in a transect with a fi ve-meter spacing. The same was done with pairs of opaque and transparent bottles. A bait (rye bread with unrefi ned sunfl ower oil) was put into all the bottles. During the following days we recorded animals’ visits into the bottles. It was found out that there are no signifi cant diff erences in how often animals attend bottles of 0,25 liters and 0,5 liters, the same results were received for both transparent and opaque bottles. Thus, the simple method for estimating abundance of small mammals may be optimized by using smaller bottles, the colour of which is not important.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):51-57
51-57
The effects of phenoloxidase inhibitors on the efficacy of malachite green decolorization by Azospirillum bacteria
Abstract
Synthetic dyes are widely used in various branches of light industry. Due to the insuffi cient effi ciency of industrial painting processes, a large percentage of dyes end up in the wastewater of enterprises in an unmodifi ed form, which creates a huge risk of environmental pollution with these compounds. Triphenylmethane dyes, in particular malachite green, are toxic, allergenic and carcinogenic compounds. To date, biodegradability of triphenylmethane dyes has been shown for some bacteria and fungi producing phenol oxidase complex enzymes, including soil associative bacteria of the genus Azospirillum. Many factors are capable of inducing and inhibiting the biodegradation effi ciency, in particular the enzymatic systems that are involved in bleaching processes. In the present work we studied the eff ects of typical deactivating agents of phenol oxidases, such as H2 O2 , EDTA, SDS-Na, β-mercaptoethanol, dithiothreitol, Tween, and sodium azide, on the azospirilla’s phenol oxidases activity and the ability to decolorize malachite green. It was found that Tween and sodium azide do not have an inhibitory eff ect on azospirillum enzymes and exhibit a total stabilizing eff ect on the entire complex. An inhibitory eff ect from 60 to 100% was noted for laccase and Mn-peroxidase activity under the action of β-mercaptoethanol, dithiothreitol and EDTA, which is directly proportional to the decolorization rate of malachite green. Compared with the latest issues on classical phenol-oxidizing enzymes, our data revealed non-typical properties of the phenol oxidase complex enzymes of azospirillum.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):58-66
58-66
Effect of Azospirillum palustre B2 lipopolysaccharide on wheat seedlings (Triticum aestivum L.)
Abstract
Lipopolysaccharide is the main structural component of the outer membrane of Gram-negative bacteria, which can also be a part of extracellular polymeric substances. Lipopolysaccharides of bacteria that stimulate the growth and development of plants belong to the group of molecules that form a microbe-associated molecular pattern (MAMP). These glycoconjugates of both symbiotic and phytopathogenic bacteria induce the activation of immune responses in plants. However, the level of plant response under the infl uence of symbiont lipopolysaccharides diff ers signifi cantly, also due to their structural features, which make it possible to bypass or weaken the reactions of innate autoimmunity. In this paper, we present the results of the analysis of the reactions of wheat seedlings Triticum aestivum L. after incubation with lipopolysaccharide of associative bacteria Azospirillum palustre B2(T). Incubation of wheat seedlings in the presence of A. palustre B2 lipopolysaccharide for three days led to the activation of plant growth processes, namely an increase in the length of shoots, roots, the area of the fi rst leaf, and a change in the content of pigments in the leaves.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):67-75
67-75
A new subspecies of gelechiid moths from the genus Neofriseria (Lepidoptera, Gelechiidae) from the Lower Volga Region (Russia)
Abstract
The article provides a brief analysis on the species composition of microlepidopteran genus Neofriseria Sattler, 1960 (Gelechiidae) of the fauna of Russia and some neighboring countries. A list of six species of this genus known for the territory of Russia at present is given. One species of the genus, previously described only relating to males from Greece, is recorded for Russia (Saratov region) firstly as a new subspecies with a description and illustrations of the genital structures of both sexes. Differences in the structure of the male genitalia between the nominative subspecies and N. b. volgensis Piskunov et Anikin, ssp. n. were analysed.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):76-83
76-83
Ecology
Analysis of natural and anthropogenic factors aff ecting the ability of Lepidium sativum L. to adapt to the toxicity of triazole xenobiotics
Abstract
The eff ects of natural factors (temperatures +34°C and +20°C) and anthropogenic xenobiotics (1,2,4-TriH; 1-(CH3 SO2 )-1H-1,2,4-Tri; 4-(PhSO2 )-4H-1,2,4-Tri; 4-(TolSO2 )-4H-1,2,4-Tri) on watercress Lepidium sativum L. was studied. For this, 4 series of experiments were carried out. In the fi rst two series, the eff ect of concentrations was studied: 0.001, 0.01, 0.1 mg/ml during germination at diff erent temperatures for three days. It was found that the ability of the triazole compounds to inhibit the germination of watercress seeds increased with increasing concentration of the solutions. The magnitude of lipophilicity was the determining factor in their toxicity. Diff erences between the infl uence of the studied temperatures on the energy of seed germination weren’t revealed. The ability of the synthesized triazoles to inhibit the growth of watercress roots and stems increased with increasing their concentration. At the same time, their toxicity was signifi cantly higher at the higher of the studied temperatures. The next two series examined the ability of Lepidium sativum to adapt to the toxicity of triazoles. To do this, the seeds were germinated during the day at contrasting temperatures in solutions with a concentration of 0.001 mg/ml, then they were germinated in solutions of 0.1 mg/ml for two days. It turned out that triazoles had signifi cantly diff erent eff ects on the development of the adaptive response in plants. Only 4-(PhSO2 )-4H-1,2,4-Tri; 4-(TolSO2 )-4H-1,2,4-Tri caused a signifi cant development of an adaptive response, the magnitude of which also depended on the cultivation temperature. We found that the value of lipophilicity of the studied triazoles was of signifi cant importance during their direct action, and the values of their molecular weight and molecular volume were important for the development of preadaptation.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):84-95
84-95
New information on the distribution of cicads (Insecta, Homoptera, Cicadinea) in the Amur river basin (Khabarovskii krai) in specially protected areas
Abstract
The distribution of cicadas in the Khabarovskii Krai has been studied very poorly, in contrast to the Amurskaya Oblast’ and Primorskii Krai. Ledra auditura (Ledridae) (also recorded from the eastern part of Zabaikal’skii Krai, the Argun River basin), Glossocratus foveolatus (Cicadellidae), Eoscartopsis assimilis (Cercopidae), Taihorina geisha (Machaerotidae), Cicadetta yezoensis (Cicadidae), Delphax maritima (Delphacidae), Mysidioides sapporensis, Losbanosia hibarensis, Zoraida albicans, Z. horishana (Derbidae), Cixidia ussuriensis, Kosalya fl avostrigata (Achilidae), Saigona ussuriensis (Dictyopharidae), Limois emelianovi (Fulgoridae) are recorded for the fi rst time in the River Amur basin from Khabarovskii Krai.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):96-102
96-102
Adventive component of the seed bank of some forest communities of the Volga River islands
Abstract
The paper presents the results of studying the adventive component of the seed bank of the Oak Mane Island of the Volga River Valley in the vicinity of the city of Saratov. Seeds of 12 species of adventitious plants were registered in the seed bank of the studied forest communities. All identifi ed seeds belong to plant species belonging to one department of Magnoliophyta, 8 families and 12 genera. The Asteraceae family plays a leading role in the taxonomic spectrum of adventitious seed bank species (42%). Mesophytic mesotrophic (63.6%) heliophytic grouping of plants dominates in relation to ecological regimes. Mostly there are species of North American origin (60%). Herbaceous annuals (33% of species) and trees (34%) play a signifi cant role. A signifi cant impact on the composition of seed banks was caused by the unintentional entry of seeds of plants that are “refugees from culture” into this territory. Most adventitious plants, represented by both vegetating individuals and seeds, have penetrated into natural cenoses, and in some cases even partially transformed their structure, which is due to their reproductive potential and ability to compete with representatives of the native fl ora of natural habitats. In the studied area, foci of the concentration of seeds of drift plants in diff erent communities were revealed, in continuous placement (Acer negundo, Bidens frondosa and Populus alba), disjunctive (Fraxinus pennsylvanica, Parthenocissus quinquefolia, Echinocystis lobáta, Impatiens glandulifera), sporadic – Ambrosia trifida, Artemisia sieversiana, Crataegus sanguinea, Inula caspica and Ulmus pumila. An increase in the number of adventitious species presented in the seed bank was recorded, but the number of seeds decreased.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):103-110
103-110
Influence of recreation on radial growth of the common pine tree
Abstract
The article deals with the stages of recreational digression of diff erent biogeocenoses in the Shirokovsky district forestry of the National Park “Buzuluksky Bor” and the peculiarities of radial growth of the common pine as a dominant stand. The aim of the work was to analyze the comparative response of the common pine trees in the zone of active recreation and in undisturbed areas. The presence or absence of undergrowth, understorey, projective cover and dominance of indicator plants were noted. Sub-tree enumeration with averaged data was carried out on temporary sample plots. Using a Flir i7 thermal imager, the presence or absence and localization of stem and root rots of pine from sponges were determined. A decrease in the total projective cover of the living ground cover and the number of forest species was observed, with an increase in the number of cereal species as recreational digression increased. As recreation intensifi es, undergrowth and understorey disappears. It was noted that with increasing stages of digression the monotony of undergrowth species composition appears, the density and height of forest litter decreases, the number of trees infected with rots and infested with stem pests (black pine moustache, pine bark beetles, six-toothed bark beetle, apex bark beetle) increases. Changes in all components of biogeocenosis lead to loss of stability of forest phytocenosis as a whole. Even a simple stay of a large number of people in the forest leads to degradation of plant communities.
Izvestiya of Saratov University. New series. Series: Chemistry. Biology. Ecology. 2024;24(1):111-117
111-117