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Abstract Gd3+- free carbon dots (CDs) were synthesized by one-step solvothermal method using urea, citric acid and 3-(trifluoromethyl)aniline as precursors. Additionally, Gd3+-doped CDs were prepared by incorporating gadolinium chloride (Gd3+ ions) into the synthesis. Size selection of the purified CDs was achieved through filter membranes ranging from 3 kDa to 100 kDa. The chemical composition and optical properties of the obtained samples were characterized by Energy dispersive X-ray (EDX), Fourier-transform infrared spectroscopy (FTIR), Dynamic Light Scattering (DLS), proton relaxation time measurements, Ultraviolet–visible (UV-vis) and fluorescence spectroscopies. A comparative analysis revealed a strong size-dependent behavior in the optical properties of both Gd3+-doped and Gd3+-free CDs. Furthermore, in vitro tests confirmed the non-cytotoxicity of Gd3+-doped CDs, indicating their potential applicability in biomedicine for magnetic resonance imaging (MRI) and red fluorescence-based cell and tissue imaging.

Understanding the interactions between drugs and enzymes is crucial for designing effective therapeutics. This study employed a combination of molecular docking and molecular dynamics (MD) simulations to evaluate the binding affinity, stability, and dynamic behavior of two new compounds (compound 1 and compound 2) compared to vancomycin and meropenem against Staphylococcus aureus and Serratia marcescens bacterial enzymes. Molecular docking studies provided insights into the binding interactions and affinities of these compounds, revealing that both compound 1 and compound 2 exhibit promising binding profiles. In particular, compound 1 demonstrated lower binding energies with key enzymes from Staphylococcus aureus compared to vancomycin, suggesting enhanced potential. MD simulations further elucidated the dynamic stability of these complexes. Results indicated that compound 1 maintains consistent binding modes with low RMSD and RMSF values, implying stable interactions. In contrast, vancomycin exhibited high RMSD and RMSF values in some enzyme complexes, reflecting potential instability. Compound 2 showed competitive stability and binding behavior compared to meropenem, with comparable RMSD and RMSF values across various enzyme targets. These findings highlight the potential of compound 1 and compound 2 as viable candidates for further development, offering insights into their stability and efficacy as new therapeutic agents.

The impact of the active hostilities associated with Russia’s large-scale armed invasion of the territory of Ukraine on soil degradation as a result of military actions has resulted in soil damage due to heavy military armored vehicles. Debris from destroyed military equipment, ammunition, and fuel remnants lead to multi-factor damage to the soil system, causing local and global pollution and losses of soil resources. In all the studied cases, mechanical, chemical, and physical soil degradation were observed. This was manifested in changes in granulometric fractions at explosion sites, burning areas, and locations with heavy-metal contamination. Equipment incineration has resulted in an increase in the sand fraction (2.0–0.05 mm) by 1.2–1.8 times and a decrease in the clay fraction (

Background/Objectives. Bacteriophages have gained significant interest as a potential solution to combat harmful bacteria, especially in the fight against antimicrobial resistance. With the rise in drug-resistant microorganisms, the medical community is increasingly exploring new alternatives to traditional antibiotics, and bacteriophages offer several advantages in this regard. However, phage applications still face some challenges, such as host specificity. Methods. In this study, a somatic Siphovirus-like coliphage (SOM7) was tested for inhibiting the biofilm-forming capacity of the non-target strain Pseudomonas aeruginosa (ATTC 10145). The phage-sensitive strain E. coli WG5 was used as a control. The selected microorganisms were first tested for growth in the presence of SOM7 at three different concentrations (105, 107, and 109 PFU/mL). Results. As expected, the phage-sensitive E. coli WG5 was fully inhibited by the coliphage, and no phage-related affection on the growth rate was observed for the SOM7-resistant P. aeruginosa. More notably, increasing concentrations of SOM7 significantly reduced both the biofilm-forming capacity and the amount of pre-established bacterial biofilm of the phage-insensitive P. aeruginosa (24.9% and 38.8% reduction in the biofilm-forming ability, and 18.8% and 28.0% biofilm degradation for 107 PFU/mL and 109 PFU/mL SOM7, respectively; p < 0.05). These results were supported by transmission electron microscopy (TEM) imaging, providing unprecedent evidence for the interaction of the somatic coliphage with the non-host strain. Conclusions. Although more studies in other biofilm models are necessary, our results show for the very first time that bacteriophages could potentially be used as an alternative to achieve desired anti-biofilm and biofilm-degrading activity in non-host bacterial strains.

Streptomycetes are known as producers of bioactive substances, particularly antibiotics. Streptomyces netropsis IMV Ac-5025 simultaneously produces different classes of antibiotics, including polyene compounds, phytohormones, and sterols, but the metabolic pathways involved in their biosynthesis are largely understudied. The aim of this work was to explore the biosynthesis of polyene antibiotics, sterols, and phytohormones when the producer is cultivated in a nutrient medium supplemented with exogenous β-sitosterol. Gas chromatography and high-performance liquid chromatography were applied to analyze the spectrum of bioactive compounds. The obtained results demonstrated not only an increase in the accumulation of biomass but also polyene antibiotics, intracellular sterols, auxins, and cytokinins, when cultivating S. netropsis IMV Ac-5025 in a liquid medium with the addition of β-sitosterol. The amount of biomass raised 1.5–2-fold, whilst the sum of polyene antibiotics increased 4.5-fold, sterols’ sum (ergosterol, cholesterol, stigmasterol, β-sitosterol, and 24-epibrassinolide) by 2.9-fold, auxins’ sum (indole-3-acetic acid, indole-3-acetic acid hydrazide, indole-3-carbinol, indole-3-butyric acid, indole-3-carboxaldehyde, and indole-3-carboxylic acid) by 6-fold, and cytokinins’ sum (zeatin, isopentyladenine, zeatin riboside, and isopentenyladenosine) by 11-fold. Thus, we put forward the hypothesis that β-sitosterol plays a regulatory role in the network of biosynthetic reactions of S. netropsis IMV Ac-5025.

Terrestrial ecosystems play a crucial role in the formation of soil resistome and the spread of antibiotic-resistant bacteria. Comprehensive studies of soil microbial communities, their structure, integrity, and level of antibiotic resistance (AR) in various terrestrial ecosystems were conducted. In total, 389 strains of dominant bacteria were isolated from the studied ecosystems, 57 of which were resistant to antibiotics, with levels of antibiotic resistance exceeding 70%. The soil microbiome of primeval forests was characterized by a low content of bacteria resistant to antibiotics; only two species, Bacillus cereus and Pantoea agglomerans, showed a high resistance to antibiotics. In the soil of agroecosystems of medicinal plants, among 106 strains of bacteria, a high level of resistance to antibiotics was found in 13 species. It was established that the number of antibiotic-resistant bacteria is highest in the soil of agroecosystems contaminated by enrofloxacin. Among 190 tested bacterial strains, 42 (22%) were characterized by a high level of antibiotic resistance. Therefore, the soil ecosystem is a key link in the formation and spread of antibiotic-resistant bacteria, which is a potential danger to humans. To reduce the risk of AR for humans, it is necessary to take appropriate measures to manage the soil microbiome and avoid soil contamination with antibiotics.

The weed Solidago canadensis L. poses a global threat to the environment as it spreads uncontrollably on roadsides, in forests, fields, meadows, and farmland. Goldenrod emits toxic substances that suppress other plants on the site, displacing wild ones. Thus, goldenrod conquers huge areas very quickly. The use of herbicides and mechanical methods does not solve the problem of the spontaneous spread of goldenrod. On the other hand, many scientists consider goldenrod as a valuable source of biologically active substances: flavonoids, phenolic compounds, vitamins, etc. In this study, we consider Solidago plants as a promising, free (cheap), and renewable substrate for the production of methane gas. The goal of the study was to identify the main patterns of degradation of the Solidago canadensis L. plant by methane-producing and sulfate-reducing bacteria with methane gas production and simultaneous detoxification of toxic copper. The composition of the gas phase was monitored by gas chromatography. The pH and redox potential parameters were determined potentiometrically; metal concentrations were measured by photometry. The concentration of flavonoids, sugars and phenolic compounds in plant biomass was determined according to well-known protocols. As a result of the study, high efficiencies of methane degradation in the Solidago plant and copper detoxification were obtained. Methane yield has reached the value of 68.2 L kg−1 TS of Solidago canadensis L. biomass. The degradation coefficient (Kd) was also high at 21.4. The Cu(II) was effectively immobilized by methanogens and sulfate reducers during the goldenrod degradation at the initial concentrations of 500 mg L−1. Thus, a new method of beneficial application of invasive plants was presented. The result confirms the possibility of using methanogenic microorganisms to produce methane gas from invasive weeds and detoxification of toxic metals.

Environmental pollution by toxic metals is a common ecological problem. Chromium and copper compounds released into the environment as a result of human-made stress pose a serious threat to living organisms. Phytoremediation is a promising method of toxic metals removal from contaminated sites. The concentration of metals in grass biomass—in the roots and aerial parts—was determined by X-ray fluorescence analysis. The estimation of numbers of microorganisms was conducted by a tenfold dilution and spread-plating method. It was shown that lawn grass accumulated from 69.1 ± 13.2 to 497.7 ± 74.1 mg/kg Cu and Cr during the growth in the contaminated soil with 50, 100, and 200 mg/kg of metals. In general, there was a pattern of accumulation of copper in the aerial part of the grass and chromium in the roots. Thus, the total copper concentration in the aerial part ranged from 105.2 ± 23.8 to 497.7 ± 74.1 mg/kg of plant biomass. The total chromium concentration in the roots ranged from 156.4 ± 47.9 to 426.8 ± 62.5 mg/kg. The viability of the soil microbiome was not inhibited at such metal concentrations. The obtained data allow lawn grass to be considered as promising for the phytoremediation of contaminated areas.