No 9 (2024)

Lichens are the oldest symbiotic organisms. Their thallus represents a structure created by a mycobiont for a population of photobiont cells, the presence of which transforms a fungal heterotrophic organism into an autotrophic association. The review article summarizes the results of ecological and physiological studies of lichens in the taiga zone on the European North-East of Russia. The data on the photosynthetic activity, the effects of environmental factors on the thallus photosynthesis, and the reactions aimed at fine-tuning the functional structure and metabolism of lichens to habitat conditions are presented and analyzed. The importance of the photobiont type for the functioning of the entire lichen association is demonstrated. Cyanobiont lichens were found to be characterized by a higher nitrogen content and intensive metabolism, compared with chlorobionts. In most of the studied lichen species, the content of chlorophyll a varied within 0.4-0.8 mg/g of the dry mass of thallus, and the concentration of carotenoids was by 2.5-3 times as less. The maximum net uptake of CO₂ in lichens was observed at a temperature of 15-20 °C and a relative water content of about 60 %. The saturation of photosynthesis with light was noted at a photosynthetic photon flux density being by four-five times less than that of the total solar radiation. The effects of exposure of thalli to UV radiation and environmental pollution with bauxite dust have been revealed. Promising directions for further research are outlined.

Lichens are ancient symbiotic organisms that can survive in extreme conditions through unique resistance mechanisms. Lichens are associations between a fungus (mycobiont) and algae and/or cyanobacteria (photobionts). The photobiont composition of lichen can determine the specificity of the stress response to abiotic factors, including unfavorable temperatures. This work analysed stress-induced changes in the photosynthetic activity and content of chlorophylls and carotenoids on the closely related Peltigera canina and Peltigera aphthosa lichens, which differ by photobiontic composition, under elevated temperature. Stress treatment resulted in a decrease in the photochemical activity of photosystem II (PSII) in both lichens. By the analysis of stress-induced changes in the content of photosynthetic pigments in lichens, the exposure to elevated temperature of the P. canina lichen induced astaxanthin accumulation but P. aphthosa significantly decreased in the content of chlorophyll а and xanthophylls synthesized from β-carotene. Thus, the identified significant differences in the composition of chlorophylls and carotenoids in the studied lichens suggest the involvement of various mechanisms of stress response to the action of elevated temperature due to the specificity of their photobiontic composition.

The paper presents the first data on the diversity of lichens in building-stone quarries in the vicinity of Vorkuta (south dwarf shrub tundra subzone). The self-regenerative succession in quarries lasts for about 40-50 years. The soil-forming rocks in quarries do not actually differ from those in the background territories by texture but were characterized by a high carbonate content due to calcite. 69 lichen taxa were identified on loamy, gravel-sandy and sandy deposits of the quarries, among them 66 species and three subspecies. The species saturation of lichens at key sites of the quarries reaches 33 species per 100 m², which exceeds the background value (26 species per 100 m²). This increase is related to the specificity of soil material conditions (presence of carbonates, gravel), vacant places in ecological niches, absence/low abundance of edificatory species, presence of species at different succession stages. In contrast to the background sites, the secondary quarry communities increase in the proportion of epibryophytes among ecologic-substrate group and scaly lichens among life forms. The lichen flora of quarries includes a significant number of calciphile species that makes it peculiar in comparison with the background areas. The quarries have been found for six lichen species included into the Red Data Book of the Komi Republic and its Annex 1.

The lowland swamps of the Russian Federation are mainly located on lands of the State Forest Fund. After peat collection with rotary cultivator, it is quite logical to use these depleted areas to plant artificial coniferous forest stands on them, for example Scots pine (Pinus sylvestris). The most favorable environment for this forest crop is low-deposit and well-drained areas with high-ash residual woody-grassy peats, underlain by light rocks. The stock of commercial wood in 40–50-year-old stands reaches 360–415 m³/ha. Areas with high peat reserves and low-ash grassy-moss species on residual peat have formed a sparse, stunted, extremely depressed forest stand in conditions of stagnant water regime. At the similar age, the timber stock does not exceed 0.1–0.2 m³/ha. All this situation must be taken into account when carrying out large-scale forest-planting operations on depleted peatlands.

Lignocellulosic waste represents the most abundant renewable raw material globally. The principles of a circular economy can be applied by optimizing the utilization of valuable properties from recycled materials. The objective of this study is to assess the potential of utilizing coffee silverskin, the sole by-product of coffee roasting, for submerged cultivation of xylotrophic basidiomycetes with subsequent enzyme production. The growth processes of Fomitopsis pinicola and Rhodofomes roseus became intensified along with the increased biosynthesis of enzymes in their mycelia in case of submerged cultivation on coffee silverskin, not during solid-phase cultivation. The Fomitopsis pinicola strain was observed to preferentially accumulate cellobiases (1800 units/g) and β-glucanases (1170 units/g), whereas the Rhodofomes roseus strain was found to accumulate xylanases (over 5000 units/g). Therefore, coffee silverskin can be recommended to be used as a promising substrate for the cultivation of xylotrophic basidiomycetes for the production of enzyme preparations.

The modern society takes a keen interest in healthy longevity and possibilities of slowing down the age-related diseases. Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that declares itself in adult people (at the age of about 60 years) and is characterized by loss of motor activity, degeneration of motor neurons in brain and spinal cord, and, finally, by respiratory arrest. The disease is currently incurable with its action mechanisms largely understudied but the scientists actively search for therapeutic drugs to further reduce the number of possible complications and delay the negative effects of the disease. Previously, we demonstrated the positive heroprotective potential of black chokeberry (×Sorbaronia mitschurinii) extract on the wild-type line Canton-S on short-term application and observed the increase in the median lifespan of males and females of the elav[c155]-Gal4>UAS-Aβ42 line, which is a model of Alzheimer’s disease in Drosophila. In the present work, we proposed a hypothesis on a possible positive effect of black chokeberry extract at concentrations of 0.1, 1, 5 and 10 mg/mL on the survival of a Drosophila line with the model of amyotrophic lateral sclerosis (with mutation in the Sod1ⁿ¹ gene). We found that the ethanolic extract of black chokeberry fruits at a concentration of 0.1 mg/mL increased the median lifespan of males by 22 %. When the extract was added to food at concentrations of 1 and 5 mg/mL, we observed a decrease in median and maximum lifespan of males by 14 and 33 %, respectively. However, the ethanolic extract of black chokeberry at any concentrations studied had no statistically significant effect on the survival of females. These results indicate a potential neuroprotective effect of the extract of black chokeberry fruits.

Arctic Russia is home to more than 90 % of all Long-tailed Ducks in the Clangula hyemalis species from the Western Siberia/Northern Europe population. The main wintering grounds of Long-tailed Ducks are situated in the Baltic Sea. The principal migratory routes of the Long-tailed Duck between the breeding and wintering grounds are relatively well-studied and follow the so-called Norwegian route along the Barents Sea coastline via the Pomorskij Strait, over the Kolguyev Island, the Kaninskij Peninsula and the White Sea. The secondary migration routes are still understudied. It has been determined that a portion of the population regularly migrates through the eastern part of Ukraine and European Russia, including the Komi Republic, the Kirov Region, the Nizhny Novgorod and Perm Regions, and the Republics of Udmurtia, Mari El, and Bashkortostan. Thus, a portion of the population utilises the «Volga-Caspian» migration route. This migration route is not as massive and covers a broad area. Long-tailed Ducks migrate in flocks of 4 to 56 individuals. Sometimes, there may be a higher intensity of migration. It is highly likely that the wintering grounds of these birds are located in the Caspian and Black Seas, where 4-5 thousand Long-tailed Ducks were counted within a relatively small area. A detailed study of all relevant ecological aspects is needed to contribute to the conservation of the Long-tailed Duck.