Listeria species are commonly found in various environments and contaminated food, with livestock serving as a significant source of foodborne pathogens. Among these species, Listeria monocytogenes (L. monocytogenes) is particularly noteworthy as it can affect both livestock and humans. Antibiotics are frequently used in food animals for disease treatment and prevention on a large scale. This practice can lead to the selection of antibiotic-resistant bacterial strains, which can then spread to humans through the food chain. Consequently, L. monocytogenes, a ubiquitous foodborne pathogen, has been associated with global outbreaks of foodborne illnesses. To address this concern, the aim of the study was to conduct comprehensive typing and genetic analysis of 13 L. monocytogenes isolates obtained from food and food-processing environments.

Among the 13 L. monocytogenes isolates, eight sequence types (ST) were identified: two isolates were identified as belonging to ST9; one as ST155; four as ST3, two as ST121, one as ST8; one as ST87; one as ST1; and one new ST belonging to CC121. Core-genome clustering analysis of L. monocytogenes was made to assess the genetic relatedness among the isolates. The core genome Multilocus Sequence Typing (cgMLST) analysis revealed three genetic clusters of high closely related isolates (£7 allelic differences (ADs)): cluster 1. Regarding L. monocytogenes typing, ST3 was the most prevalent among the isolates, found in 4 isolates, followed by ST9 and ST121. Some of these isolates, like ST1, ST9 and ST87, were previously associated with human clinical cases. We used Whole Genome Sequencing (WGS) alongside epidemiological data to link strains to human illnesses and potential food sources. Through cgMLST analysis, we identified genetic clusters of closely related isolates, all linked to the same producers.

This approach helped us pinpoint common sources of contamination and gain insights into the transmission dynamics of L. monocytogenes in the context of food safety and public health. The escalating antibiotic resistance in Listeria species, particularly in L. monocytogenes, emphasizes the need for heightened surveillance and improved hygiene practices in the food industry to curb the spread of antibiotic resistance and ensure food safety.

Cefiderocol is a new cephalosporin–siderophore conjugate antibiotic highly effective against infections caused by extensively-drug-resistant Gram-negative bacilli. Antimicrobial susceptibility testing of cefiderocol is challenging due to its unique mechanism of action which puts the microdilution as the most and only reliable method. Easier and cheaper test accepted by EUCATS for cefiderocol antimicrobial susceptibility is disc diffusion. But the quality control results of this method provide evidence that there is still an area of technical uncertainty.

This study aimed to test whether the type of medium on which the tested strain was initially cultured affects the cefiderocol susceptibility disc diffusion testing.

The disk diffusion susceptibility test for cefiderocol was performed on 50 clinical Klebsiella pneumoniae MBL isolates following the EUCAST methodology. Isolates were previously cultured on 3 different kinds of microbiological media, routinely used in clinical microbiology laboratories: Blood Agar, MacConkey Agar, Chromogenic Agar; acquired from 3 different manufacturers. Cefiderocol minimal inhibitory concentration (MIC) for all tested strains was determined using microdilution.

All growth inhibition zones had a statistically significant negative correlation with MIC values. No significant differences were observed between the inhibition zones on Blood and MacConkey Agar from different manufacturers, and no significant differences were observed when comparing Blood Agar vs. MacConkey Agar. Comparing Chromogenic Agar from different manufacturers, and in comparison to other media, significant differences were observed.

Blood and MacConkey Agar results should be carefully examined – colonies grown on these media can be used in cefiderocol susceptibility testing. Chromogenic Agar should not be used for susceptibility testing.

Most common and frequently used class of antibiotics are beta-lactams. Although
antibiotics are most crucial organic compounds, but their low degradability and fast
accumulation in the environment is now causing trouble as micropollutants. World Health
Organisation has now declared antibiotics resistances as global health concern as well as
silent pandemic. Rapid increase in resistance has developed superbugs which survive even to
the last resort antibiotics. One of the ways to combat the antibiotics resistance is to degrade or
biotransform them into less toxic form in the environment. Therefore, to combat this
situation, microbial derived beta-lactamases are capable of degrading all beta-lactam
antibiotics. In this study, beta-lactamase producing bacteria were isolated from sludge of
pharmaceutical waste water treatment plant. The beta-lactamase producing bacteria were
screened using iodometric and double disc diffusion assay respectively. Further, selected
bacterial isolates were tested for degradation of three classes of beta-lactam antibiotics using
in vitro assays. Degradation was confirmed by TLC, UV-Vis spectroscopy and iodometric
assay. Degraded product completely loses its antimicrobial activity. The long-term goal of the
study is to characterise bio-transformed products by LCMS and GCMS and determine how
effectively beta-lactamase degrades antibiotics in a mixed antibiotic environment.

Background: Multidrug-resistant bacterial infections pose a severe public health crisis due to limited antibiotic development, threatening a return to the pre-antibiotic era and incurring substantial human and financial costs. Pseudomonas aeruginosa, a challenging multidrug-resistant pathogen, adds complexity with its drug resistance mechanisms and pathogenic factors.

Bacteriophages, viruses targeting bacteria, offer distinct advantages over antibiotics, such as specificity, replication within hosts, and minimal disruption to natural microflora, supporting their efficacy in preventing and treating bacterial infections, particularly in immunocompromised patients. Hydrogels, biomimetic materials, exhibit potential as a stable and controlled delivery system for phages, creating new avenues for combatting antibiotic-resistant infections. This research aims to evaluate the potential of stable phage hydrogel formulation for controlling Pseudomonas aeruginosa.

Methods: Bacteriophages were propagated from a phage stock, and hydrogels were prepared with sodium carboxymethyl cellulose in different solutions, followed by rheological analysis. Phage release from hydrogels was assessed qualitatively and quantitatively, and the stability of formulations was evaluated under various storage conditions. Efficacy was determined by testing the product against laboratory and hospital-derived bacterial strains, with absorbance measurements recorded.

Results: The hydrogel-based delivery system inhibited bacterial growth effectively, with laboratory strains reaching a 53.5% inhibition at 5 hours, and clinical strains exhibiting varying levels of inhibition, one sample achieving 68.3% inhibition at 4.5 hours. Notably, the formulated product showed comparable effectiveness to erythromycin gel against laboratory bacteria.

Conclusion: This study signifies progress in utilizing hydrogels for phage delivery to combat antibiotic-resistant infections, providing an alternative therapeutic approach to traditional antibiotics. The study reveals hydrogels' potential as a phage delivery system for combating antibiotic-resistant infections, demonstrating effective inhibition of bacterial growth within an hour of incubation. The rheological analysis indicated the suitability of these formulations for biomedical applications.

The emergence and rapid development of microbial resistance to antibacterial drugs is one of the major problems for modern science and medicine. One of the methods being developed to address the problem is the design of hybrid antibacterial substances based on two different pharmacophores covalently linked to each other. In this work, we synthesized and characterized two sets of hybrid compounds, in which azithromycin was bound to chloramphenicol or metronidazole at 4″ position using linker fragments of different length and structure. Almost all conjugates were shown to efficiently inhibit protein synthesis in vitro in a cell-free bacterial translation system similar to azithromycin. Moreover, we demonstrate that novel derivatives of azithromycin are active against Escherichia coli strain inducibly resistant to macrolide antibiotics due to the ermCL-dependent regulation of ErmC methyltransferase synthesis. Further toe-printing analysis revealed a premature ribosome stalling at the Phe codon (UUU), as well as the absence of ribosome arrest at positions characteristic of azithromycin (and crucial for the regulation or ErmC synthesis) in the presence of hybrid compounds. Thus, we demonstrate that novel derivatives of azithromycin have a preference to cause premature ribosome stalling during translation, which makes them active against bacterial strains inducibly resistant to the typical macrolide antibiotics. Investigation of the mechanism of action of the synthesized compounds was funded by the Russian Science Foundation according to the research project No. 21-64-00006.

Antibiotics are an important milestone in medicine; however, their increased use has resulted in an alarming rise of antimicrobial resistances. Antibiotics are used in large quantities not only in human medicine but also in animal farming and agriculture, where they enter the environment through waste products, feces, or milk of treated cows, promoting antimicrobial resistance, and ultimately leading to untreatable multidrug-resistant pathogens threatening also human health. Importantly, antibiotic-resistant bacteria often activate export mechanisms that result in resistance to various structurally unrelated antibiotics.

We devised a novel strategy for the enzymatic inactivation of antibiotics in different media such as salt water or milk. Using a combinatorial approach and metabolic selection, we optimized a hydrolase enzyme (EstDL136) for cleavage of the antibiotic florfenicol. Time-resolved nuclear magnetic resonance spectroscopy revealed significantly improved reaction kinetics for the optimized variant. Importantly, the hydrolase remained active in different media such as saltwater or cow milk.

Various environmentally-friendly application strategies for florfenicol inactivation were developed using the optimized hydrolase. As potential filter device for cost-effective treatment of waste milk or aquacultural wastewater, the hydrolase was immobilized on Ni-NTA agarose or silica as carrier materials. In two further application examples, the hydrolase was used as cell extract or encapsulated with a semi-permeable membrane. This facilitated, for example, florfenicol inactivation in whole milk, which can help to treat waste milk from medicated cows, to be fed to calves without the risk of inducing antibiotic resistances.

In general, our strategies for enzymatic inactivation of antibiotics enables therapeutic intervention without promoting antibiotic resistances.

Background: Piper betel leaf belongs to the family of Piperaceae. Many active metabolites from betel leaf such as hydroxychavicol and phenolic compounds have been proven in literature to have potent anti bacterial efficacy. Aim: The present study aimed to evaluate the antifungal efficacy of betel leaf and Vitex trifolia against oral candida species. Methodology: Leaves of betel leaf & Vitex trifolia were procured, dried and ground to fine powder. Dimethyl sulfoxide was used as solvent. Antifungal efficacy was evaluated by agar well diffusion method. Molecular docking was also done using Autodock Vina. Results: Zone of inhibition was evaluated to study the compare the antifungal efficacy of Piper betel leaf & Vitex trifolia. Binding of betel leaf & Vitex trifolia were analysed for both C.albicans and C.glabrata. Conclusion: Vitex trifolia had better anti fungal efficacy than betel leaf. Antifungal efficacy and molecular bonding was better for C.albicans than C.glabrata

Introduction: Candidiasis is a common mucocutaneous fungal infection mainly caused by Candida albicans. Infection can occur in moist areas specially in skin folds, genitals cuticlea and also in oral mucosa. Oropharyngeal candidiasis will cause white plaques on oral mucosa. Now a days resistance is developing for all diseases. In that way when there is any resistance to regular antifungal drugs, natural herbs will be an excellent option to overcome the situation.

Aim: Antifungal property with minimum inhibitory concentration of Spirulina platensis (Spirulina) is evaluated against Candida albicans and also to find the zone of inhibition for Spirulina platensis (Spirulina) against Candida albicans and Candida glabrata.

Methods: Alcoholic extract of Spirulina platensis (Spirulina)was prepared. Zone of inhibition for Candida albicans and glabrata was performed by well diffusion method and antifungal property with minimum inhibitory concentration for Spirulina platensis (Spirulina) against Candida albicans was done by Agar Dilution method.

Results: Zone of inhibition of Spirulina platensis is present of about 25mm against C. glabrata, and 26mm against C. albicans and Minimum inhibitory concentration of Spirulina platensis (Spirulina) is also found at 4mg of alcoholic extract. The results are statistically significant(p<0.05)

Conclusion: Spirulina platensis can be used as an antifungal agent when traditional antifungal treatment is not working or in any cases of antifungal resistance.

Vultures play a key role in the ecosystem. They help to remove the decaying organic material from the environment and therefore help to reduce the spread of pathogenic microorganisms in the ecosystem. Vultures can be contaminated by different bacteria, viruses and fungi (some zoonotic) when they feed, which can in turn contaminate other animal species and even humans. Vultures can be actively exposed to multidrug-resistant bacteria when they consume contaminated carcasses. A total of 20 works between the years 2011 to 2021 were analysed. The studies were performed on Cathartes aura (n=1), Gyps bengalensis (n=1), Neophron percnopterus majorensis (n=3), Neophron percnopterus percnopterus (n=3), Gyps fulvus (n=5), and Aegypius monachus (n=4). Most studies were performed on faecal samples, and the isolated bacteria were mostly faecal flora microbiota, with Escherichia coli as one of the most studied microorganisms (n=12). From a One Health perspective, it helps to understand how these animals can be excellent environment sentinels and a tool for measuring the health of ecosystems health and humans with whom they share their habitat.

Chronic wounds (CWs) are frequently associated with bacterial infections. The development of antibiotic-resistant microorganisms makes it crucial to think of alternative solutions. Considering these issues, a drug delivery system made of coaxial wet-spun fibers loaded with essential oils (EOs) was proposed. Coaxial structures were produced using the wet-spinning technique, in which 10% w/v polycaprolactone (PCL, a synthetic polymer with excellent mechanical properties and elastic behavior) was used to produce the core and loaded with three EOs, Clove Oil (CO), Cinnamon Leaf Oil (CLO) and Tea Tree Oil (TTO) at 2×Minimum Bactericidal Concentration (MBC). The shell was made of a blend of 10% w/v cellulose acetate (CA, a natural polymer which has been reported to offer good structural integrity) and 10% w/v polyethylene glycol (PEG, a synthetic polymer often used as a plasticizer), mixed at a ratio of 90/10 v/v, respectively, so pores could be opened in the outer layer, allowing for a sustained release of the EOs loaded at the fibers’ core overtime. The formation of coaxial structures was confirmed by Brightfield Microscopy. Coaxial fibers exhibited high maximum elongations at break (≈350%). EO-loaded fibers were effective against S. aureus, S. epidermidis, E. coli and P. aeruginosa, the most common bacteria present in CWs. Results confirmed the potential of the engineered coaxial wet-spun fibers for wound healing applications. Still, further characterization on the fibers is necessary, including cytocompatibility tests to assure non-toxic profiles of the fibers when in contact with fibroblasts and keratinocytes.