No 6 (2025)

In halophytes from the coast of the Kandalaksha Bay of the White Sea, the occurrence and content of metabolites of the mycotoxin group were studied by enzyme immunoassay. Typical metabolites were emodin, alternariol, mycophenolic acid, while T-2 toxin and roridin A were not found. A number of features of the metabolic profile of plants was revealed — the presence of fumonisins (Zostera marina); ochratoxin A, citrinin, diacetoxyscirpenol, deoxynivalenol, zearalenone and PR-toxin (Glaux maritima); nitrogen-containing compounds — cyclopiazonic acid and ergot alkaloids (Cochlearia groenlandica, G. maritima, Puccinellia maritima, Triglochin maritima); a significant content of emodin and sterigmatocystin (Honekenya pepioides); rare cases of contamination (Aster tripolium, Plantago maritima). For C. groenlandica, P. maritima and Salicornia pojarkovae selected in different years from remote ecotopes, a significant variability in the contents of emodin and alternariol has been established. The possible participation of their endophytes in responses of plants to changes in habitat conditions is discussed.

Dendrochronological analysis of oak (Quercus robur L.) and ash (Fraxinus excelsior L.) trees sampled in Kozelsk Zaseki allowed us to reconstruct the disturbance history of a part of this forest area for the last 150 years. Large and medium scale disturbances were detected in 1868, 1940, 1957, 1971 and 1977. In the last case, the results of the dendrochronological analysis are supported by archival documents. It is shown that after disturbances both studied species show significant increase in the percentage of tree-rings with higher number of earlywood vessel rows. Similar changes in anatomical structure may occur in response to extreme floods and winter frosts. Possible mechanisms of the formation of the studied anatomical features are considered.

The data on hybridization of house mice in nature and experiments accumulated over the last decades are summarized and analyzed. When analyzing hybridization of house mice in natural conditions, the emphasis is placed on discussing the accumulated information on the European hybrid zone between Mus musculus musculus and M. m. domesticus and its use in studying postzygotic reproductive barriers between fertile parental forms. In experimental conditions, hybridization of house mice is considered in the review more broadly, but mainly with the involvement of the same inbred lines of Mus musculus s. str. extracted from nature or bred from them. The problems of reduced viability, genomic incompatibility in hybrids, interspecific and intraspecific hybrid sterility (factors causing it, role in speciation) are analyzed. The analysis of the results on the molecular-cytogenetic mechanisms of hybrid sterility caused by various meiotic anomalies associated with impaired fertility, as well as on the gene control of the phenomenon observed during hybridization of house mice, was carried out.

In liver disease, pannexin 1 (Panx1) expression in hepatic tissue increases, whereas genetic deletion of Panx1 appears to exert a protective effect against disease progression. This study aimed to explore the role of Panx1 in regulating mesenteric arterial tone in a mouse model of obstructive cholestasis (OC), induced by common bile duct ligation for three weeks. In wild-type mice, OC elevated Panx1 expression in mesenteric arteries, but contractile responses to an α1-adrenoceptor agonist and ATP remained unchanged. In contrast, mesenteric arteries from Panx1 knockout mice exhibited enhanced responses to both agonists under OC, along with increased NTPDase1 mRNA levels. These effects of OC in knockout animals may be associated with the activation of Panx1-independent pathways of ATP release from cells.

Observations on different types of water bodies were carried out to study the relationship between chlorophyll and suspended organic carbon. Using literature and proprietary material, a simple method for estimating phytoplankton carbon in situ depending on the concentration of chlorophyll a, based on classical and quantile regression analysis, is demonstrated. Calculations yielded the ordinary estimates of carbon/chlorophyll ratios ranging from 25 to 150.

The climate regulating potential of Russian peat bogs are considering primarily as a huge reservoir of organic carbon accumulated in various soil horizons. At the same time, due to limited economic value the sparse forests and other woody vegetation of peat bogs is poorly studied. However, forest trees and other woody vegetation growing on peatlands are occupying big area and integrally may provide a significant contribution to the absorption of carbon dioxide. The results of satellite observations indicate the processes of afforestation of open peat bogs in different regions of Russia. A systematic study of these processes for entire Russia was based on satellite monitoring data for the period of the years 2001–2024. It was estimated that the area of open peat bogs annually identified over the country varies in the range of 121.5–129.5 million hectares. At the same time, the dynamics of their area is characterized by a downward trend at about 346 000 hectares per year, and in the period of the years 2011–2024, the magnitude of this negative trend reached 622 000 hectares per year. The area of peat bogs covered with forests and sparse trees increased during this period by 5.5 million hectares, and its average annual increase was estimated at about 241 000 hectares per year.

The literature data on the use of larvae of the black beetle (Zophobas morio) for biodegradation of various plastics such as polystyrene, polyethylene, polypropylene, polyurethane foam, polyvinyl chloride, etc. are briefly summarized. Brief information is provided on the volume of plastic waste generation in the Russian Federation and in the world, information on the main methods of recycling used polymer materials is briefly given. Information is provided on the morphology of imago and larvae of Z. morio. It has been shown that insect larvae can use plastics as the only source of carbon, effectively decomposing the latter due to the action of a consortium of intestinal microorganisms. Isolated and identified strains of microorganisms that decompose plastics are described, in most cases, due to a decrease in molecular weight, size and oxidation under the action of enzymes. Utilization of polymer materials by biodegradation due to feeding on insect larvae has prospects for development and is intensively developing in the global space.

The nucleotide sequences polymorphism of the trnL-trnF, rpl16 intron, and matK regions of chloroplast DNA of the medicinal plant Eleutherococcus senticosus in the south of the Russian Far East (RFE) has been studied. The level of genetic diversity was found to be high in the populations of Primorsky Krai and average on Sakhalin Island. Hierarchical analysis of molecular variance showed very low and insignificant genetic differentiation between the populations of these two regions (Φ_CT = 0.043, P > 0.479); more than 62% of all genetic variability accounted for the intrapopulation component (Φ_ST = 0.377, P = 0.000). Eleven haplotypes were identified on the RFE, one of which was private and two were rare for species. All haplotypes known for E. senticosus form a single group with minimal divergence between each other.