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Synthetic hydroxyapatite (HA) materials with antibacterial and biocompatible properties have potential for biomedical applications. The application of various computational methods in silica is highly relevant for the optimal development of modern materials. In this work, we used molecular docking to determine the binding constants of tetracycline (TET) and quercetin (QUE) with hydroxyapatite and compared them to experimental data of the adsorption of tetracycline (TET) and quercetin (QUE) on the HA surface. The experimental adsorption study was performed via the UV-VIS method. The fabricated biocidal powders were characterized via X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The electrical charge of the HA particle surface was determined via zeta potential measurements. The molecular docking method was used to predict the binding affinities of TET and QUE for HA. We also performed molecular docking studies to predict the binding affinity of TET and QUE for HA. These affinities correlate with the experimental binding constants, suggesting that molecular docking is a good tool for material property prediction. In addition, the antimicrobial activity of the HA/TET and HA/QUE powders was determined against 2 g-positive bacterial strains: S. aureus and E. faecalis . The obtained HA powders were evaluated for biocompatibility in vitro with the myoblast cell line C2C12., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

Chemical investigation of the hydnoid fungus Sarcodontia setosa resulted in the isolation of five compounds, including two new sarcodontic acid derivatives - setosic acid ( 1 ) and 7,8-dehydrohomosarcodontic acid ( 2 ) along with three known benzoquinone pigments - sarcodontic acid ( 3 ), 4,5-dehydrosarcodontic acid ( 4 ) and dihydrosarcodontic acid ( 5 ). The structures were elucidated using spectroscopic methods (UV, NMR and HR-ESIMS). The biosynthetic relationship of the isolated compounds is proposed and discussed. Antibacterial activity screening of compounds 1 - 5 against ESKAPE bacterial strains in vitro with zones of inhibition was performed and MIC values were established for the most active compounds ( 3 and 5 ).

Disinfectants play a crucial role in controlling the spread of infectious diseases caused by bacteria and spore-forming organisms. Bacteria and spores can persist on surfaces and in the environment for extended periods, posing a significant risk to public health. Disinfectants are designed to inactivate or kill these microorganisms by disrupting their cellular structures and functions. Effective disinfectants are essential for preventing the spread of infectious diseases in hospitals, laboratories, food processing facilities, and other settings where the risk of contamination is high. This study evaluated the effectiveness of a disinfectant called "MultiDez" on Y.pestis bacteria and Bacillus anthracis spores using microbiological and electron microscopic methods. Results showed that after exposure to a 0.5 % solution of the disinfectant, the death of all Y.pestis bacteria was achieved after 90 min, while the death of Bacillus anthracis spores was achieved after 240 min. Electron microscopy revealed that the disinfectant caused complete destruction of both bacterial cells and spores by enveloping their outer surfaces with polymer molecules, disrupting the structure and function of their membranes, and destroying their cytoplasm and nucleode. The mechanism of action of the disinfectant on bacteria and spores involved different processes, with the disinfectant causing rapid hydration of dehydrated spores and blocking the functions of spore membranes in the case of bacterial spores., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 Published by Elsevier Ltd.)

An orthogonal reactivity of diazo compounds toward azirine-2-carboxylic acids, switching with the reaction conditions, is demonstrated. A gold-catalyzed reaction is N-selective and produces 1,3-oxazin-6-ones, whereas a blue light activation leads to O-H insertion products, azirine-2-carboxylic esters. The observed chemodivergence is explained by the metal-bound and metal-free carbenes exhibiting different electronic properties in these reactions. In addition, a high antibacterial potential of the 1,3-oxazin-6-ones synthesized is shown.

A new route to 5-amino-1,2,4-thiadiazole derivatives via reaction of N-chloroamidines with isothiocyanates has been proposed. The advantages of this method are high product yields (up to 93%), the column chromatography-free workup procedure, scalability and the absence of additive oxidizing agents or transition metal catalysts. The 28 examples of 5-amino-1,2,4-thiadiazole derivatives obtaining via the proposing protocol were evaluated in vitro against ESKAPE pathogens strains (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter cloacae). It was found that compounds 5ba, 5bd, 6a, 6d and 6c have potent antibacterial activity (MIC values 0.09-1.5 μg mL -1 ), which is superior to the activity of commercial antibiotics such as pefloxacin (MIC 4-8 μg mL -1 ) and streptomycin (MIC 2-32 μg mL -1 ). The additional cytotoxic assay of hit compounds on PANC-1 cell line demonstrated the low or non-cytotoxicity activity at the same level of concentrations. Thus, these 5 compounds are promising starting point for further antimicrobial drug development., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The antibiotic resistance (ABR) problem is becoming increasingly disturbing and it is important to implement express methods of ABR testing to allow operative antibiotic therapy decisions. The application of laser light scattering (LLS) in microbiological analysis for express ABR testing of microorganisms has been considered. The ways of miniaturization of laser light scattering for creating the bases of their integration into microbiological laboratory-on-a-chip (MLOC) for clinical express diagnostics have been analysed. The advantage of miniaturization in the context of clinical express analysis realization problems are investigated. A system of parallel measuring cells and illumination, enabling simultaneous testing of a group of antibiotics, was tested by splitting a laser beam with a two-dimensional collimator prepared of nanoporous anodic aluminum oxide. It has been demonstrated that the application of LLS methods, providing high concentration and mass sensitivity as well as a miniaturization potential, is an effective approach in the development of new generation diagnostic instruments. The studies have demonstrated the ability of methods to register effects of antibiotics on microbiological samples within 10 min. The following microorganisms were used in the study: Escherichia coli M-17, Lactobacillus plantarum , Bifidobacterium bifidum , Stenotrophomonas maltophilia .

When creating titanium-containing bone implants, the bioactive coatings that promote their rapid engraftment are important. The engraftment rate of titanium implants with bone tissue depends significantly on the modification of the implant surface. It is achieved by changing either the relief or the chemical composition of the surface layer, as well as a combination of these two factors. In this work, we studied the creation of composite coatings with a two-level (the micro- and nanolevel) hierarchy of the surface relief, which have bioactive and bactericidal properties, which are promising for bone implantation. Using the developed non-lithographic template electrochemical synthesis, a composite coating on titanium with a controlled surface structure was created based on an island-type TiO 2 film, silver and hydroxyapatite (HAp). This TiO 2 /Ag/HAp composite coating has a developed surface relief at the micro- and nanolevels and has a significant cytological response and the ability to accelerate osteosynthesis, and also has an antibacterial effect. Thus, the developed biomaterial is suitable for production of dental and orthopedic implants with improved biomedical properties.

Chemical investigation of the polypore fungus Fistulina hepatica resulted in the isolation of five compounds, including four new polyacetylenic fatty acid derivatives - isocinnatriacetin B (1), isocinnatriacetin A (2), cinna-triacetin C (3) and ethylcinnatriacetin A (4) together with one known polyacetylene fatty acid derivative - cinnatriacetin A (5). The structures were elucidated using spectroscopic methods (UV, NMR, HR-ESIMS) along with comparison to literature data. Antibacterial activity screening of compounds 1-5 against ESKAPE bacterial strains in vitro with zones of inhibition (ZOI) was performed and MIC values were established for the most active compounds (3 and 4). Together with that morphological and growth parameters under solid-phase cultivation were also researched.