Investigation of antifungal and antibacterial potential of green extracts of propolis.

Propolis extracts have been used in traditional medicines since ages due to its advantageous complex chemical composition. However, the antibacterial and antifungal activity of poplar propolis extracts prepared in Natural Deep Eutectic Solvent (NADES) are seldom studied. This study investigates suitable alternate for ethanol as a solvent for extraction for Polish poplar propolis.

Oxolane Ammonium Salts (Muscarine-Like)-Synthesis and Microbiological Activity.

Commercially available 2-deoxy-D-ribose was used to synthesize the appropriate oxolane derivative-(2,3)-2-(hydroxymethyl)oxolan-3-ol-by reduction and dehydration/cyclization in an acidic aqueous solution. Its monotosyl derivative, as a result of the quaternization reaction, allowed us to obtain eight new muscarine-type derivatives containing a quaternary nitrogen atom and a hydroxyl group linked to the oxolane ring. Their structure was fully confirmed by the results of NMR, MS and IR analyses.

In Silico Safety Assessment of Isolated from Polish Bee Pollen and Bee Bread as Novel Probiotic Candidates.

species isolated from Polish bee pollen (BP) and bee bread (BB) were characterized for in silico probiotic and safety attributes. A probiogenomics approach was used, and in-depth genomic analysis was performed using a wide array of bioinformatics tools to investigate the presence of virulence and antibiotic resistance properties, mobile genetic elements, and secondary metabolites. Functional annotation and Carbohydrate-Active enZYmes (CAZYme) profiling revealed the presence of genes and a repertoire of probiotics properties promoting enzymes.

Probiotic potential of Bacillus Isolates from Polish Bee Pollen and Bee Bread.

The main goal of this study was the evaluation of the probiotic potential of 10 Bacillus spp. strains isolated from 5 bee bread and 3 bee pollen samples. The antagonistic interaction with Staphylococcus aureus and Escherichia coli was a primary criterion for the preliminary selection of the isolates.

Whole-genome sequencing and antimicrobial potential of bacteria isolated from Polish honey.

The aim of this study was the whole-genome analysis and assessment of the antimicrobial potential of bacterial isolates from honey harvested in one geographical location-the north of Poland. In total, 132 strains were derived from three honey samples, and the antimicrobial activity of CFAM (cell-free after-culture medium) was used as a criterion for strain selection and detailed genomic investigation. Two of the tested isolates (SZA14 and SZA16) were classified as Bacillus paralicheniformis, and one isolate (SZB3) as Bacillus subtilis based on their ANI and phylogenetic analysis relatedness.

Hydrazinolysis Products of Selected Sugar Lactones-Crystal Structure and Microbiological Activity.

Commercially available lactones, as well as those synthesized by us, turned out to be good substrates for the synthesis of sugar hydrazides. The exception was L-ascorbic acid, whose hydrazinolysis led to the formation of a hydrazinium salt, not the hydrazide as expected. The structure of all compounds was confirmed by NMR and X-ray analyses.

Synthesis, Antimicrobial and Mutagenic Activity of a New Class of d-Xylopyranosides.

Eight -[2-(2',3',4'-tri--acetyl-α/β-d-xylopyranosyloxy)ethyl]ammonium bromides, a new class of d-xylopyranosides containing a quaternary ammonium aglycone, were obtained. Their complete structure was confirmed using NMR spectroscopy (H, C, COSY and HSQC) and high-resolution mass spectrometry (HRMS). An antimicrobial activity against fungi (, ) and bacteria (, ) and a mutagenic Ames test with TA 98 strain were performed for the obtained compounds.

Fatty acids as molecular carriers in cleavable antifungal conjugates.

Conjugates composed of C fatty acid (FA) residues as a molecular carrier and 5-fluorocytosine (5-FC) as an active agent, released upon the action of intracellular esterases on the ester bond between FA and "trimethyl lock" intramolecular linker, demonstrate good in vitro activity against human pathogenic yeasts of Candida spp. The minimal inhibitory concentrations (MIC) values for the most active conjugates containing caprylic (C), capric (C), lauric (C), or myristic (C) acid residues were in the 2-64 μg mL range, except for these against the least susceptible Candida krusei. The least active conjugates containing C, C or C FA were slowly hydrolyzed by esterase and probably poorly taken up by Candida cells, as found for their analogs containing a fluorescent label, Nap-NH instead of 5-FC.

Virulence analysis and antibiotic resistance of Klebsiella pneumoniae isolates from hospitalised patients in Poland.

Klebsiella pneumoniae (KP) is a nosocomial pathogen causing difficult-to-treat infections. The presence of virulence genes and antibiotic resistance of 109 KP isolates from hospitalized patients were investigated. Among them, 68.

New Peptide Based Fluconazole Conjugates with Expanded Molecular Targets.

Infections of spp. etiology are frequently treated with azole drugs. Among azoles, the most widely used in the clinical scenario remains fluconazole (FLC).

Antimicrobial, Cytotoxic and Mutagenic Activity of Gemini QAS Derivatives of 1,4:3,6-Dianhydro-l-iditol.

A series of quaternary diammonium salts derivatives of 1,4:3,6-dianhydro-l-iditol were synthesized, using isommanide (1,4:3,6-dianhydro-d-mannitol) as a starting material. Both aromatic (pyridine, 4-(,-dimethylamino)pyridine (DMAP), (3-carboxamide)pyridine; -methylimidazole) and aliphatic (trimethylamine, ,-dimethylhexylamine, ,-dimethyloctylamine, ,-dimethyldecylamine) amines were used, giving eight gemini quaternary ammonium salts (QAS). All salts were tested for their antimicrobial activity against yeasts, and , as well as bacterial and reference strains.

Quest for the Molecular Basis of Improved Selective Toxicity of Isomers of Aromatic Heptaene Macrolide Antifungal Antibiotics.

Three aromatic heptaene macrolide antifungal antibiotics, Candicidin D, Partricin A (Gedamycin) and Partricin B (Vacidin) were subjected to controlled photochemical isomerization. The obtained isomers demonstrated substantially improved in vitro selective toxicity in the cells: human erythrocytes model. This effect was mainly due to the diminished hemotoxicity.

Bee Pollen and Bee Bread as a Source of Bacteria Producing Antimicrobials.

The principal objective of the study was the isolation and identification of bacteria that are present in mature bee bread (BB) and dried (ready for selling and consumption) bee pollen (BP). Obtained isolates were screened for their potential to inhibit select human pathogenic bacteria and their ability to produce enzymes of particular industrial importance. Four and five samples of BP and BB, respectively, were used for the study.

Antibiotic Resistance of Uropathogens Isolated from Patients Hospitalized in District Hospital in Central Poland in 2020.

The aim of this study was to determine antibiotic resistance patterns and the prevalence of uropathogenes causing urinary tract infections (UTIs) in patients hospitalized in January-June 2020 in central Poland. Antimicrobial susceptibility testing was performed using the disk-diffusion method. (52.

Editorial for the Special Issue: "Honey Bee Products as an Alternative or Complement to Classical Antibiotics".

Based on World Health Organization reports, the resistance of bacteria to well-known antibiotics is becoming a major global health challenge [...

Synergistic Effects of Propolis Combined with 2-Phenoxyethanol and Antipyretics on the Growth of .

The present investigation aimed to assess the combinational effect of commonly used antipyretics and antiseptics with ethanolic extracts of propolis (EEPs) on the growth inhibition of . The broth microdilution checkerboard assay revealed synergistic interactions between all investigated antipyretics, namely acetylsalicylic acid, ibuprofen, and acetaminophen, with EEPs samples. The values of the fractional inhibitory concentration (ΣFIC) index for all these combinations were <0.

Bee Bread Exhibits Higher Antimicrobial Potential Compared to Bee Pollen.

This study aimed at investigation of the antimicrobial potential of ethanolic extracts of bee bread (BB) and bee pollen (BP) and suspensions of these products in MHB (Mueller Hinton Broth). We covered 30 samples of BP and 19 samples of BB harvested in Polish apiaries. Slightly lower activity was observed against Gram-negative bacteria compared to Gram-positive staphylococci.

Effect of Ethanol Extracts of Propolis (EEPs) against Staphylococcal Biofilm-Microscopic Studies.

Staphylococci growing in the form of biofilm exhibit high resistance to a plethora of antibiotics. The aim of the study was to assess the influence of ethanolic extract of propolis (EEPs) on ATCC 35984 biofilm using fluorescent microscopy. Propidium iodide (PI) and SYTO 9 were used for differentiation of live and dead cells, and calcofluor white was used to stain the extracellular matrix, the self-produced extracellular polymeric substances (EPS).

Draft genome sequence of antimicrobial producing Paenibacillus alvei strain MP1 reveals putative novel antimicrobials.

Objective: A Paenibacillus strain isolated in previous research exhibited antimicrobial activity against relevant human pathogens including Staphylococcus aureus and Listeria monocytogenes. In this study, the genome of the aforementioned strain, designated as MP1, was shotgun sequenced. The draft genome of strain MP1 was subject to multiple genomic analyses to taxonomically characterize it and identify the genes potentially responsible for its antimicrobial activity.

as a Producer of the Proteinaceous Compound with Activity against Important Human Pathogens, Including and .

An emerging need for new classes of antibiotics is, on the one hand, evident as antimicrobial resistance continues to rise. On the other hand, the awareness of the pros and cons of chemically synthesized compounds' extensive use leads to a search for new metabolites in already known reservoirs. Previous research showed that strain ( MP1) recovered from a buckwheat honey sample presented a wide spectrum of antimicrobial activity against both Gram-positive and Gram-negative pathogens.

New Approaches for Genotyping.

Easy-to-perform, fast, and inexpensive methods of differentiation of strains beyond the species level are highly required. Herein two new, original tools for genotyping of E. coli isolates are proposed.

Anthra[1,2-][1,2,3]triazine-4,7,12(3)-triones as a New Class of Antistaphylococcal Agents: Synthesis and Biological Evaluation.

The development and spread of resistance of human pathogenic bacteria to the action of commonly used antibacterial drugs is one of the key problems in modern medicine. One of the especially dangerous and easily developing antibiotic resistant bacterial species is Anthra[1,2-][1,2,3]triazine-4,7,12(3)-triones - have been developed as novel effective antistaphylococcal agents. These compounds have been obtained by sequential conversion of 1-amino-9,10-dioxo-9,10-dihydroanthracene-2-carboxylic acid () and 1-amino-4-bromo-9,10-dioxo-9,10-dihydroanthracene-2-carboxylic acid () into the corresponding amides -, followed by subsequent endo-cyclization under the influence of sodium nitrite in acetic acid.

Voriconazole-Based Salts Are Active against Multidrug-Resistant Human Pathogenic Yeasts.

Voriconazole (VOR) hydrochloride is unequivocally converted into VOR lactates and valinates upon reaction with silver salts of organic acids. This study found that the anticandidal in vitro activity of these compounds was comparable or slightly better than that of VOR. The clinical isolate overexpressing genes, highly resistant to VOR, was apparently more susceptible to VOR salts.

Gas-phase removal of indoor volatile organic compounds and airborne microorganisms over mono- and bimetal-modified (Pt, Cu, Ag) titanium(IV) oxide nanocomposites.

The photocatalytic deactivation of volatile organic compounds and mold fungi using TiO modified with mono- and bimetallic (Pt, Cu, Ag) particles is reported in this study. The mono- and bimetal-modified (Pt, Cu, Ag) titanium(IV) oxide photocatalysts were prepared by chemical reduction method and characterized using XRD, XPS, DR/UV-Vis, BET, and TEM analysis. The effect of incident light, type and content of mono- and bimetallic nanoparticles deposited on titanium(IV) oxide was studied.

The Anti-Staphylococcal Potential of Ethanolic Polish Propolis Extracts.

The principal objective of this study was to determine the anti-staphylococcal potential of ethanol extracts of propolis (EEPs). A total of 20 samples of propolis collected from apiaries located in different regions of Poland were used in the study. The two-fold broth microdilution method revealed some important differences in the antimicrobial activity of investigated EEPs.