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Enzymatic hydrolysis is an environmentally friendly technology to produce sugars from pretreated biomass. Here, we show that the new Il-11 Irpex lacteus strain can synthesize cellulases in a high quantity. The peptone and filter paper contained in the medium significantly enhanced activity of endo-1,4-ß-D-glucanases (app. 50 IU/mL) and total cellulases (app. 9 IU/mL), whereas the medium with peptone and sodium carboxymethyl cellulose stimulated activity of exo-1,4-ß-D-glucanases (33 IU/mL). The expression of cellulases reached its maximum within 96-144 hours, and the optimum pH is 3,7. Thermal treatment at 30 °C for 60 minutes activated endo-1,4-ß-D-glucanases and total cellulases, while exo-1,4-ß-D-glucanases activity was enhanced following 40 °C treatment. In total, the cellulases complex (300 IU/g) saccharified untreated cellulose by 38 % in 48 hours. Concentrate with filter paper activity 100 IU/g is the more balanced enzyme-substrate ratio (2 %), which allows prolonging the saccharification process that will have a positive effect on the cost of the final product. [ABSTRACT FROM AUTHOR]

Herbarium collections have proven to be irreplaceable information base in recent studies directed towards revealing shifts in plants phenology and morphology caused by climate change. We examined eight parameters of morphological traits in the perennial herb species Plantago lanceolata L. collected in the wild between 1905 and 2019 and stored at the KW-herbarium (Kyiv, Ukraine) to find out if there were changes in plants' organ sizes during the last 114 years. For this period, we also calculated 13 climatic parameters obtained from meteorological records from the State archive that gave us the opportunity to check if there are any relations between the climate change in Kyiv region and shifts in morphological parameters of plants. Our results have shown Plantago lanceolata leaf blades, petioles and spikes had become significantly longer with time, increasing 3.0 cm, 2.1 cm and 0.6 cm respectively. The Co-inertia analysis revealed that 34% of the morphological changes was attributed to climate change. The analysis also demonstrated that leaf length correlated more with raised temperatures when plants were in flower, while spike length depended on the temperatures during bud development. Received knowledge can be used to reveal rapid evolutionary processes of the Plantago species and predicting their further course for the construction of historical climate models based on the leaves traits. [ABSTRACT FROM AUTHOR]

Climate change has a significant impact on natural ecosystems, particularly on floodplain forests that are among the most transformed ecosystems in the world. The climate sensitivity of dominant species is likely to play a key role in determining the susceptibility of flooded forests to climate changes. Here, we use dendrochronological approaches and local climate records from 1880 to 2015 to assess the response in pedunculate oak (Quercus robur L.) trees growing in a floodplain of the Dnipro River near Kyiv to climatic variables. Correlation analysis reveals the strongest positive association of the Q. robur tree-ring width chronology with May-June precipitation, May-June temperature, and May self-calibrating Palmers drought severity indices (scPDSI). The moving-window correlation analysis points to positive association with the scPDSI after the 1950s, when local river regulation was implemented. The positive correlation with current March precipitation is the least expected change in the oak growth-to-climate relationship that occurred in the aftermath of human alterations in the local river and regional climate changes. This study discusses the probable ecological consequences and ecophysiological mechanisms of observable climate-to-growth relationships and their temporal stability. [ABSTRACT FROM AUTHOR]

Red wood ants are capable of active thermoregulation in the nest, which allows them to achieve a high number of workers and a dominant position in biocenoses. We investigated the features of the spring warm-up and the ability for active thermoregulation of the mounds of the ants Formica polyctena and F. rufa in the vicinity of Kyiv, Ukraine. We have proposed a model of thermoregulation of the mound, which takes into account the heat flow from the sun, heat exchange with air and soil, and endogenous heat generated by the antcolony. The calculation of the model for specific values showed that only F. polyctena mounds with a diameter of more than 0.9 m and F. rufa mounds with a diameter of more than 1.1 m are able to maintain a constant optimum temperature in the nest. Comparison of the calculated data with the measurement results onthe studied nests showed that the diameters of the majority of moundsexceededthe critical values for both speciesindicatingthe ability ofthermoregulation. The possibility of using the model to study the thermoregulation of moundsin different natural areas is discussed. [ABSTRACT FROM AUTHOR]

Studying four species of red wood ants (Formica rufa, F. polyctena, F. aquilonia, F. lugubris), we examined nest morphometrics (height and diameter of anthills), spatial parameters (location of anthills of different sizes relative to each other), and the number of trails per colony in three regions of Ukraine and Russia: Kyiv region (877 anthills), the Urals (274 anthills) and Cis-Baikal (72 anthills). We have established a relationship between the number of anthills in the nest complex and the maximum parameters of the average height and diameter, as well as the average number of trails. Under optimal conditions, the infrastructure of the forage area of red wood ants becomes more complex - an increase in the average number of trails. We have shown that the morphometric parameters of anthills differ significantly in four species of red wood ants. In addition, it was confirmed that single anthills are on average smaller than colonial ones and have, on average, fewer trails per anthill. There is a pronounced spatial aggregation between the anthills of red wood ants of the same species (F. rufa, F. polyctena, Kyiv population) of all size classes. [ABSTRACT FROM AUTHOR]