Rising environmental pollution poses a significant threat to bat populations worldwide, raising serious ecological and conservation concerns. Here, we present the first assessment of cytogenotoxic stress responses in cave-dwelling insectivorous bats from the karst island of Cat Ba in northern Vietnam, in relation to anthropogenic pollution. The study aimed to evaluate the association between exposure to heavy metals (HMs) and DNA damage, as well as blood alterations in bats, using minimally -invasive biomarkers. We applied an integrated approach combining three indicators: HM accumulation in guano (a hallmark of exposure), micronucleus (MN) frequency (a measure of genotoxicity), and the polychromatic-to-normochromatic erythrocyte (PCEs/NCES) ratio (a measure of cytotoxicity). Guano-derived cadmium (Cd) and lead (Pb) levels correlated strongly with genotoxic markers, confirming guano as a reliable indicator of HM contamination at the population level. Species- and site- specific cytogenotoxic responses to HM stress were manifested through the formation of MNs and the reduction of the PCEs/NCEs ratio, signifying the presence of DNA damage, suppression of bone marrow activity, and disruption of erythropoiesis. Combining guano chemistry with cytogenotoxic biomarkers provides a sensitive and non-invasive tool for monitoring environmental stress in bat populations in karst ecosystems.
A series of Co, Co-Bi, and Co-Mg/g-C3N4 (graphitic carbon nitride) composites with 5 wt% metal content were synthesized via a one-pot thermal polycondensation method using pristine and HNO3-protonated melamine as precursors for g-C3N4. The obtained catalysts were characterized by inductively coupled plasma-optical emission spectrometry, X-ray diffraction, transmission electron microscopy, Selected Area Electron Diffraction (SAED), Fourier transform infrared spectroscopy, and Brunauer-Emmett-Teller method (BET) techniques. Their catalytic performance was evaluated for peroxymonosulfate (PMS) activation and the degradation of Acid Orange 7 (AO7) and methylene blue (MB) in aqueous solutions under ambient conditions. The Co-g-C3N4 composite exhibited significantly higher catalytic activity than bare Co3O4 and pristine g-C3N4, which can be attributed to the synergistic interaction between the two components. It was found that the synthesis of g-C3N4 via pyrolysis of HNO3-protonated melamine enhances the PMS-activation capability of the resulting composite catalysts. A further enhancement in catalytic performance was achieved by modifying Co-g-C3N4 with MgO and Bi2O3. The superior performance of Co-Mg-g-C3N4 (pm) is attributed to the increased basicity of the catalyst surface. Quenching experiments using ethanol (EtOH) and tert-butyl alcohol (TBA) as radical scavengers confirmed the generation of sulfate radicals in the investigated systems. In addition, the effects of catalyst dosage, PMS/dye molar ratio, and initial solution pH on the degradation rates of AO7 and MB were also examined.
Urbanisation is a major driver of ecological change, altering the composition and functioning of ecosystems through land use conversion, pollution, and environmental fragmentation. Although some authors reported that air pollutants could be absorbed and detoxified by the endophytic microbiome of urban trees, the specific mechanisms by which urban air pollution shapes the endophytic microbiome and, consequently, the trees' capacity for pollutant degradation, remain largely unexplored. The aim of the present study was to: (1) analyse the structure of endophytic bacteriome of the phyllosphere of three widely planted ornamental tree species-Tilia tomentosa, Fraxinus excelsior, and Pinus nigra, growing at four locations within the city of Plovdiv, Bulgaria, with different anthropogenic load; and (2) assess the effects of host species and urban environmental exposure on bacteriome diversity, taxonomic composition, and functional capacity. Functional profiling based on 16S rRNA gene sequencing revealed enrichment of the metabolic pathways associated with nitrogen cycling, carbon metabolism, and hydrocarbon degradation, particularly in samples originating from more urbanised or polluted locations. These predicted functional traits suggest that endophytic bacteria may actively contribute to detoxification processes within plant tissues. Tilia tomentosa and Fraxinus excelsior were enriched in nitrogen and carbon cycling pathways, including denitrification, methanol oxidation, and methanotrophy-functions associated with oxidative stress mitigation and nutrient regulation. In contrast, Pinus nigra showed higher relative abundance of chemoheterotrophy, ureolysis, and sulphur respiration, indicating a more conservative and stress-tolerant microbiome. Although the study involved only one settlement, these results suggest that endophytic communities may contribute to urban tree sustainability by supporting ecosystem functions under stress conditions. By integrating microbial ecology with urban environmental assessment, this research provides new insights into the adaptive potential of endophytic microbiota in urban forests and highlights their importance in the sustainable management of green infrastructure through microbiome-informed strategies.
Seeds from four landraces of dry beans (Phaseolus vulgaris L. and Phaseolus coccineus L.) from the National Collection of Bulgaria were analyzed for their chemical and lipid composition. The chemical analysis revealed that protein ranged from 24.4% to 31.5%, carbohydrates from 53.1% to 56.1%, fat from 0.9% to 1.4%, fiber from 2.6% to 2.8%, and ash from 3.9% to 4.7%, indicating their high nutritional and caloric value. The seed oils contained significant levels of bioactive compounds, including tocopherols (3483-3809 mg/kg), carotenoids (1664-2049 mg/kg), and phospholipids (24.6-62.2%), which contribute to their health-promoting properties. In the Phaseolus vulgaris accessions, the oil was primarily composed of linolenic (n-3) and linoleic acids (n-6), followed by palmitic and oleic acids, whereas in the Phaseolus coccineus accession, linoleic acid (n-6) predominated, followed by linolenic (n-3) acid. beta-Sitosterol was the major sterol, followed by stigmasterol, while the tocopherol fraction was mainly composed of gamma-tocopherol (88.2-95.0%), with delta-tocopherol as a secondary component. Phosphatidylcholine was the predominant phospholipid, accounting for 33.1-51.7%. These findings underscore the potential of Bulgarian bean landraces as functional ingredients in health-oriented food products due to their balanced nutritional profile and presence of bioactive lipids.
This paper studies a new family of iterative methods for the simultaneous approximation of polynomial zeros with known multiplicities. The methods are obtained by combining the Wang-Zheng iteration function with an arbitrary iteration function. This approach leads to a class of methods referred to as Wang-Zheng-type methods with correction for multiple zeros. A local convergence analysis is developed for a wide class of iteration functions. The analysis describes the conditions under which the proposed methods converge locally. Several known iterative methods are examined as special cases of the general results. In particular, the family constructed by Kyurkchiev and Andreev (1990) is included. For every positive integer N, the N-th method of this family has convergence order 3N+1. The main local convergence theorem extends, complements and improves earlier results by Wang and Wu (1987) and by Kyurkchiev and Andreev (1990).
