Search Results (42)

The repurposing potential of Efavirenz (EFV), a clinically established non-nucleoside reverse transcriptase inhibitor, was comprehensively evaluated for its in vitro antibacterial effect either alone or in combination with other antibacterial agents on several Gram-positive clinical strains showing different antibiotic resistance profiles. The binding potential assessed by an in silico study included Penicillin-binding proteins (PBPs) and WalK membrane kinase. Despite the relatively high minimum inhibitory concentration (MIC) limiting the use of EFV as a single antibacterial agent, it exhibits significant synergistic activity at sub-MIC levels when paired with various antibiotics against Enterococcus species and Staphylococcus aureus. EFV showed restored sensitivity of β-lactams against Methicillin-resistant S. aureus (MRSA). It increased the effectiveness of antibiotics tested against Methicillin-sensitive S. aureus (MSSA). It also helped to overcome the intrinsic resistance barrier for several antibiotics in Enterococcus spp. In silico binding studies aligned remarkably with experimental antimicrobial testing results and highlighted the potential of EFV to direct the engagement of PBPs with moderate to strong binding affinities (pK_a 5.2–6.1). The dual-site PBP2 binding mechanism emerged as a novel inhibition strategy, potentially circumventing resistance mutations. Special attention should be paid to WalK binding predictions (pK_a = 4.94), referring to the potential of EFV to interfere with essential regulatory pathways controlling cell wall metabolism and virulence factor expression. These findings, in general, suggest the possibility of EFV as a promising lead for the development of new antibacterial agents. Full article

Introduction: Patients with soft tissue infection are often encountered in clinical practice. The mainstay of treatment typically includes antimicrobial therapy, followed by surgical debridement when indicated. Blood cultures are often performed prior to starting the first dose of antibiotics. However, when patients require transfer to tertiary/quaternary-level care for more advanced surgical interventions, blood cultures are often repeated despite patients being on broad-spectrum antibiotics. Our study aims to investigate the utility of blood cultures following transfer to a higher level of care. Methods: This is a retrospective study involving adult patients (≥18 years of age) who were transferred to a quaternary academic center with soft tissue infections between 15 June 2018 and 15 February 2022. Patients with incomplete medical records and/or without blood culture data after arrival were excluded. The primary outcome was the rate of positive blood cultures post-transfer. Descriptive analyses were performed, and comparisons between groups were expressed as absolute differences and 95% CI. Results: We analyzed 303 patients with a mean (+/−SD) age of 54 (14) years, and 199 (66%) were male. Necrotizing soft tissue infections (NSTIs) predominated, 198 patients (65%), with a majority of the NSTIs involving the perineum (112, 37%). The prevalence of positive blood cultures was 20 (7%) for pre-transfer and 14 (5%) for post-transfer. Among post-transfer positive blood cultures, 3 (21%) were coagulase-negative Staphylococcus aureus, with 2 (14%) cases each for the blood culture categories of polymicrobial, methicillin-sensitive Staphylococcus aureus, and Enterococcus faecalis, and 2 (14%) with Candida species. Among 112 patients with NSTIs of the perineum, 2 (14%) patients had positive blood cultures post-transfer, compared with 110 (38%) patients with negative blood cultures (difference 24%, 95% CI −0.40, −0.12, p < 0.001). Conclusions: For patients with soft tissue infection, the prevalence of positive blood culture after arrival at our quaternary care center was low at 5%. Pathogenic cases of positive blood cultures after transfer were polymicrobial, methicillin-sensitive Staphylococcus aureus and Candida species. However, the low number of post-transfer positive blood cultures limits the strength of the inference and should be interpreted cautiously. Further studies are necessary to confirm our observation. Clinicians at tertiary/quaternary care centers should consider the utility of obtaining blood cultures from patients with soft tissue infections transferred from other facilities. Full article

This study aimed to optimize the extraction of phytocompounds intended for wound care applications from three plant species, Sambucus nigra L. flowers and Epilobium hirsutum L. and Lythrum salicaria L. aerial parts, by using a Quality by Design approach. The effects of different extraction methods (ultra-turrax and ultrasonic-assisted extraction), ethanol concentrations (30%, 50%, 70%), and extraction times (3, 5, 10 min) were studied, and during the optimization step, the polyphenol and flavonoid contents were maximized. The phytochemical profiles of the optimized HEs (herbal extracts) were assessed using LC-MS/MS methods. The antioxidant capacity of the optimized HEs was determined using DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity) TEAC (Trolox equivalent antioxidant capacity), and FRAP (ferric reducing antioxidant power) assays, while the antibacterial activity was evaluated against Escherichia coli, Pseudomonas aeruginosa, and MSSA—methicillin-sensitive Staphylococcus aureus and MRSA—methicillin-resistant Staphylococcus aureus). Cell viability and antioxidant and wound healing potential were assessed on keratinocytes and fibroblasts. The anti-inflammatory effect was assessed on fibroblasts by measuring levels of interleukins IL-6 and IL-8 and the production of nitric oxide from RAW 264.7 cells. The major compounds of the optimized HEs were rutin and chlorogenic acid. The Lythrum salicaria optimized HE showed the strongest antibacterial activity, while the Sambucus nigra optimized HE demonstrated high cell viability. Lythrum salicaria and Epilobium hirsutum optimized HEs showed increased antioxidant capacities. All extracts displayed anti-inflammatory effects, and the Epilobium hirsutum optimized HE exhibited the best in vitro wound-healing effect. Full article

This study aims to characterize the conjunctival flora of patients scheduled for cataract surgery and determine the susceptibility profile of isolated bacteria to several commonly used topical antibiotics. Conjunctival swabs were taken from 44 consecutive patients (25 males, 19 females; mean age of 75.0 ± 12.6 years) who were scheduled for senile cataract surgery at two Italian centers before starting any prophylactic preoperative treatment. Swabs were processed for the detection of the microbial growth and for species identification. Selective culture media were used, and bacteria were identified using the MicroScan Specialty ID Panels (Beckman Coulter^®, Brea, CA, USA). Antimicrobial susceptibility for the following antibiotics (netilmicin, tobramycin, ofloxacin, oxacillin, levofloxacin, moxifloxacin, chloramphenicol, cefuroxime, and azithromycin) were assessed using the Kirby–Bauer disk diffusion method. Susceptibility for oxacillin was useful to identify methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE). Among the swabs analyzed, 61.4% showed only saprophytic flora, 30.7% showed only potential pathogenic flora, and 8.0% showed mixed flora. S. epidermidis (20.5%), S. intermedius (18.2%), and S. aureus (14.8%) were the most frequent isolates; MRSA and MRSE accounted for 8.0% and 6.8% of isolates. Less frequently (9%), Gram-negative bacteria such as Pseudomonas fluorescent, Serratia marcescens, Moraxella lacunata, Morganella morgani, and Stenotrophomonas maltophila were detected. All isolated organisms showed an excellent sensitivity to moxifloxacin and chloramphenicol (range 83–100%, range 67–100%, Gram-positive sensitivity for moxifloxacin and chloramphenicol, respectively; 100% Gram-negative sensitivity for both). A significant percentage of the eyes of candidates for surgery presented potential pathogenic flora alone or in association with saprophytic organisms. Staphylococci were the most frequently isolated bacteria. Tobramycin and Ofloxacin, widely used in the ophthalmic field, are confirmed to have a reduced sensitivity in vitro. Full article

Background/Objectives: Infections in dogs caused by methicillin-resistant staphylococci (MRS) present limited treatment options. This study’s objective was to investigate the molecular epidemiology of Staphylococcus spp. cultured exclusively from clinical canine skin and ear samples in Queensland, Australia, using whole-genome sequencing (WGS). Methods: Forty-two Staphylococcus spp. isolated from clinical canine skin and ear samples, from an unknown number of dogs, were sourced from two veterinary diagnostic laboratories between January 2022 and May 2023. These isolates underwent matrix-assisted laser desorption ionisation– time of flight bacterial identification, minimum inhibitory concentration testing using Sensititre^TM plates and WGS. Phylogenetic trees and core genome multilocus sequence typing (cgMLST) minimum spanning trees (MSTs) were constructed. Results: The isolates included methicillin-resistant and -sensitive S. pseudintermedius (MRSP: 57.1%, 24/42; and MSSP: 19.1%, 8/42), methicillin-resistant and -sensitive S. coagulans (MRSC: 14.3%, 6/42; and MSSC: 2.4%, 1/42) and methicillin-resistant coagulase-negative staphylococci (MR-CoNS: 7.1%, 3/42). Thirty-nine isolates were included after WGS, where all MRS harboured the mecA gene. Eighteen sequence types (STs) were identified, including three novel MRSP and six novel MSSP STs. MRSP ST496-V-VII (23%; 9/39) and MRSP ST749-IV-(IVg) (12.8%; 5/39) were commonly isolated. Phylogenetic analysis of single nucleotide polymorphisms showed that MRSP, MRSC and MSSC were similar to globally isolated staphylococci from canine skin and ear infections. Using cgMLST MSTs, MRSP isolates were not closely related to global strains. Conclusions: Our findings revealed a genotypically diverse geographical distribution and phylogenetic relatedness of staphylococci cultured from clinical canine skin and ear samples across Queensland. This highlights the importance of ongoing surveillance to aid in evidence-based treatment decisions and antimicrobial stewardship. Full article

Background/Objectives: Although Staphylococcus epidermidis is a key cause of subclinical mastitis in Danish dairy cows, its sensitivity to antimicrobials remains unexplored. Here, we analyzed sixty S. epidermidis isolates derived from 42 dairy cows across six conventional dairy herds in Denmark. Methods: Phenotypic resistance was measured by antimicrobial susceptibility testing and minimum inhibitory concentration (MIC) analysis, and genotypic resistance was examined through whole-genome sequencing and identification of antimicrobial resistance genes (ARGs). Correspondence between phenotypic and genotypic resistance was then evaluated by Cohen’s kappa statistics. Furthermore, the presence of plasmid replicon genes and the strain diversity among the S. epidermidis isolates was investigated to associate these findings with the observed AMR patterns. Results: Results showed that 30/60 isolates (50.0%) were resistant to penicillin phenotypically, while 35/60 (58.3%) were positive for a corresponding blaZ gene (κ = 0.83, p < 0.01). A fosB gene, encoding fosfomycin resistance, was detected in all 60/60 isolates (100.0%), but fosfomycin resistance was not analyzed phenotypically. Based on MIC analysis, 3/60 isolates (5.0%) were multi-drug resistant, showing resistance towards penicillin, erythromycin, and tetracycline. However, in 11/60 genomes (18.3%), ARGs encoding resistance towards ≥3 antimicrobial classes (e.g., beta-lactams, phosphonic acid, tetracyclines, aminoglycosides, macrolides, lincosamides, and fusidane) were detected. Eleven different ARGs were detected among the 60 isolates in total. No methicillin-resistant Staphylococcus epidermidis (MRSE) were recorded. Results further showed that each herd had one primary sequence type (ST) and resistance profile associated with it, and plasmid-mediated horizontal gene transfer of ARGs was indicated This study underscores the importance of routine resistance surveillance and species-specific diagnoses to improve treatment outcomes and ensure prudent use of antimicrobials. Full article

Introduction: Simvastatin is an antilipidemic drug that has already demonstrated antibacterial activities on oral and non-oral microorganisms. Silver nanoparticles also exhibit antimicrobial properties, particularly for coating implant surfaces. In this study, we evaluated the effects of combining simvastatin with silver nanoparticles on the formation and viability of biofilms consolidated on titanium discs. Methods: Silver nanoparticles were first biosynthesized using the fungus Fusarium oxysporum and then characterized using Dynamic Light Scattering, X-ray Diffraction, Transmission Electron Microscopy, and energy dispersive spectroscopy. Species of Streptococcus oralis, Streptococcus mutans, Porphyromonas gingivalis, Methicillin-sensitive Staphylococcus aureus, and Methicillin-resistant Staphylococcus aureus were used and tested using Minimum Inhibitory Concentration assays with concentrations of silver nanoparticles and simvastatin alone and in combination. Biofilm inhibition and viability tests were performed on titanium surfaces. Toxicity tests were also performed on Galleria mellonella moth larvae. Results: The silver nanoparticles had a spherical shape without the formation of aggregates as confirmed by Transmission Electron Microscopy. Dynamic Light Scattering revealed nanoparticles with an average diameter of 53.8 nm (±1.23 nm), a polydispersity index of 0.23 and a zeta potential of −25 mV (±2.19 mV). The silver nanoparticles inhibited the growth of the strains tested in the range of 0.001592 and 63.75, while simvastatin alone inhibited the growth of the same strains in the range of 3.125–62.5 µg/mL. The antibacterial activity test of the combination of the two substances showed a reduction in the Minimum Inhibitory Concentration of about two to eight times, showing synergistic effects on Staphylococcus aureus and additive effects on Streptococcus oralis and Porphyromonas gingivalis. As for biofilm, sub-inhibitory concentrations of the combination of substances showed better antibacterial activity in inhibiting the formation of Streptococcus oralis biofilm, and this combination also proved effective in eradicating already established biofilms compared to the substances alone. The combination of silver nanoparticles and simvastatin showed low toxicity to Galleria mellonella moth larvae. Conclusions: The results presented indicate that the combination of the two substances could be an alternative for the prevention and reduction of biofilms on implants. These findings open up new possibilities in the search for alternatives for the treatment of peri-implant infections, as well as the possibility of using lower doses compared to single drugs, achieving the same results and reducing potential toxic effects. Full article

The wound management field faces significant challenges due to antimicrobial resistance (AMR) and the complexity of chronic wound care. Effective wound treatment requires antimicrobial dressings to prevent bacterial infections. However, the rise of AMR necessitates new antimicrobial agents for wound dressings, particularly for addressing bacterial pathogens like methicillin-resistant Staphylococcus aureus (MRSA). Endophytic fungi, known for producing diverse bioactive compounds, represent a promising source of such new agents. This study tested thirty-two endophytic fungi from thirteen distinct Australian native plants for their antibacterial activity against S. aureus. Ethyl acetate (EtOAc) extracts from fungal culture filtrates exhibited inhibitory effects against both methicillin-sensitive S. aureus ATCC 25923 (MIC = 78.1 µg/mL) and MRSA M180920 (MIC = 78.1 µg/mL). DNA sequence analysis was employed for fungal identification. The most active sample, EL 19 (Chaetomium globosum), was selected for further analysis, revealing that its EtOAc extracts reduced S. aureus ATCC 25923 biofilm formation by 55% and cell viability by 57% to 68% at ${\displaystyle \raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.}$ × MIC. Furthermore, cytotoxicity studies using the brine shrimp lethality test demonstrated low cytotoxicity up to 6 × MIC (25% mortality rate) with an LC50 value of 639.1 µg/mL. Finally, the most active sample was incorporated into polycaprolactone (PCL) fiber mats via electrospinning, with resultant inhibition of S. aureus species. This research underscores the potential of endophytic fungi from Australian plants as sources of substances effective against common wound pathogens. Further exploration of the responsible compounds and their mechanisms could facilitate the development of wound dressings effective against MRSA and innovative biofilm-resistant electrospun fibers, contributing to the global efforts to combat AMR. Full article

Contamination of leafy greens with Staphylococcus spp. can occur at various supply chain stages, from farm to table. This study comprehensively analyzes the species diversity, antimicrobial resistance, and virulence factors of Staphylococci in salad vegetables from markets in the United Arab Emirates (UAE). A total of 343 salad items were sampled from three major cities in the UAE from May 2022 to February 2023 and tested for the presence of Staphylococcus spp. using standard culture-based methods. Species-level identification was achieved using matrix-assisted laser desorption ionization-time of flight mass spectrometry. Antimicrobial susceptibility testing was conducted using the VITEK-2 system with AST-P592 cards. Additionally, whole genome sequencing (WGS) of ten selected isolates was performed to characterize antimicrobial resistance determinants and toxin-related virulence factors. Nine Staphylococcus species were identified in 37.6% (129/343) of the tested salad items, with coagulase-negative staphylococci (CoNS) dominating (87.6% [113/129]) and S. xylosus being the most prevalent (89.4% [101/113]). S. aureus was found in 4.6% (14/343) of the salad samples, averaging 1.7 log10 CFU/g. One isolate was confirmed as methicillin-resistant S. aureus, harboring the mecA gene. It belonged to multi-locus sequence type ST-672 and spa type t384 and was isolated from imported fresh dill. Among the characterized S. xylosus (n = 45), 13.3% tested positive in the cefoxitin screen test, and 6.6% were non-susceptible to oxacillin. WGS analysis revealed that the cytolysin gene (cylR2) was the only toxin-associated factor found in S. xylosus, while a methicillin-sensitive S. aureus isolate harbored the Panton-Valentine Leukocidin (LukSF/PVL) gene. This research is the first to document the presence of methicillin-resistant S. aureus in the UAE food chain. Furthermore, S. xylosus (a coagulase-negative staphylococcus not commonly screened in food) has demonstrated phenotypic resistance to clinically relevant antimicrobials. This underscores the need for vigilant monitoring of antimicrobial resistance in bacterial contaminants, whether pathogenic or commensal, at the human-food interface. Full article

The irresponsible overuse of antibiotics has increased the occurrence of resistant bacterial strains, which represents one of the biggest patient safety risks today. Due to antibiotic resistance and biofilm formation in bacteria, it is becoming increasingly difficult to suppress the bacterial strains responsible for various chronic infections. Honey was proven to inhibit bacterial growth and biofilm development, offering an alternative solution in the treatment of resistant infections and chronic wounds. Our studies included chestnut honey, valued for its high antibacterial activity, and the bacteria Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and S. epidermidis, known to form multi-species biofilm communities. Minimum inhibitory concentrations (MIC) of chestnut honey were determined for each bacterial strain. Afterwards, the mixed bacterial biofilms were treated with chestnut honey at different stages of maturity (incubation times: 2, 4, 6, 12, 24 h). The extent of biofilm inhibition was measured with a crystal violet assay and demonstrated by scanning electron microscopy (SEM). As the incubation time increased and the biofilm became more mature, inhibition rates decreased gradually. The most sensitive biofilm was the combination MRSA-S. epidermidis, with a 93.5% inhibition rate after 2 h of incubation. Our results revealed that chestnut honey is suitable for suppressing the initial and moderately mature stages of mixed biofilms. Full article

During the current investigation, eight essential oils (EOs) were tested for their antimicrobial activity against six species, belonging to the genus of staphylococcus, multi-resistant to antibiotics (S. epidermidis, S. cohni, S. wareneri, S. scuiri, S. chromogenes, S. pasteuri), three methicillin-resistant Staphylococcus aureus strains (MRSA) and two strains of Escherichia coli, producing extended-spectrum β-lactamase (ESBL) responsible for bovine mastitis. Our results indicated that the antimicrobial activities of eight EOs varied significantly among the types of EOs and bacterial species. Thymus capitatus and Trachyspermum ammi EOs display important antibacterial activity against all tested strains, with the inhibition zone diameters situated between 20 and 45 mm, while EOs of Artemisia absinthium, Eucalyptus globulus, Eucalyptus camaldulensis, Myrtus communis and Mentha pulegium exerted an intermediate activity. For Cymbopogon citratus, this effect depends on bacteria species. In fact, an important effect was observed against S. warneri, S. epidermidis, S. cohenii, S. pasteuri and MRSA (EC 39+) strains. In addition, the important lytic effect was observed against MRSA strains, showing that Gram-positive bacteria were more sensitive to T. capitatus EO than Gram-negative ones. Concerning the characterization of the mode action of T. capitatus, experiments of kill-time, bacteriolytic, loss of salt tolerance and loss of cytoplasmic material showed that the used EO was able to destroy cell walls and membranes followed by the loss of vital intracellular materials. In addition, it inhibits the normal synthesis of DNA, causing the bacterial death of E. coli and MRSA strains. This study shows the potential of using of EOs, particularly T. capitaus, to inhibit the growth of Gram-positive and Gram-negative bacteria multi-resistant to antibiotics causing bovine mastitis. Full article

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are a global health concern. The propensity of MRSA to form biofilms is a significant contributor to its pathogenicity. Strategies to treat biofilms often involve small molecules that disperse the biofilm into planktonic cells. Linezolid and, by extension, theoxazolidinones have been developed to treat infections caused by Gram-positive bacteria such as MRSA. However, the clinical development of these antibiotics has mainly assessed the susceptibility of planktonic cells to the drug. Previous studies evaluating the anti-biofilm activity of theoxazolidinones have mainly focused on the biofilm inhibition of Enterococcus faecalis and methicillin-sensitive Staphylococcus aureus, with only a few studies investigating the activity of oxazolidinones for eradicating established biofilms for these species. Very little is known about the ability of oxazolidinones to eradicate MRSA biofilms. In this work, five oxazolidinones were assessed against MRSA biofilms using a minimum biofilm eradication concentration (MBEC) assay. All oxazolidinones had inherent antibiofilm activity. However, only ranbezolid could completely eradicate MRSA biofilms at clinically relevant concentrations. The susceptibility of the MRSA biofilms to ranbezolid was synergistically enhanced by coadministration with the nitroxide biofilm dispersal agent C-TEMPO. We presume that ranbezolid acts as a dual warhead drug, which combines the mechanism of action of the oxazolidinones with a nitric oxide donor or cytotoxic drug. Full article

The rapid emergence of resistant bacteria is occurring worldwide, endangering the efficacy of antibiotics. Hence, there is a need to search for new sources of antibiotics that either exhibit novel structures or express a new mechanism of action. The lichen Usnea, with its wide range of unique, biologically potent secondary metabolites, may solve this problem. In this study, Usnea species were collected in the Northern Philippines, identified through combined morphological and biochemical characterization, and tested for antimicrobial activities against the multidrug-resistant ESKAPE pathogens, i.e., Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter cloacae, two standard antibiotic-sensitive test bacteria, and a yeast. A total of 46 lichen specimens were collected and later identified as Usnea baileyi (10), U. diffracta (10), U. glabrata (12), U. longissima (4), and U. rubicunda (10). The results show that the crude extracts of the Usnea species exhibited promising in vitro inhibitory activities against standard antibiotic-sensitive (E. faecalis ATCC 29212) and multidrug-resistant (methicillin-resistant S. aureus and E. faecalis) Gram-positive bacteria. Additionally, lichen compounds of representative specimens per species were identified and profiled using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The detection of lichen acids (LA) via HPLC showed the presence of 24 peaks of lichen acids. TLC-bioautography identified the bioactive lichen acids as alectronic acid, connorstictic acid, consalazinic acid, diffractaic acid, echinocarpic acid, erythrin acid, galbinic acid, hypoconstictic acid, hyposalazinic acid, hypostictic acid, lobaric acid, menegazzaic acid, micareic acid, pannarin, salazinic acid, stictic acid, and usnic acid. Our study highlighted the wide spectrum of opportunities for using lichens for the discovery of potential antimicrobial agents. Full article

Hospital-acquired infections are a significant concern in healthcare settings, leading to patient safety risks, increased morbidity and mortality, and financial burdens. Hand hygiene is crucial in preventing the spread of bacteria in hospitals and communities. Manual hand sanitizer dispensers can harbor presumptive pathogenic bacteria and act as fomites for bacterial transmission. This study aimed to assess the microbial contamination of manual hand sanitizer dispensers in a hospital setting and to study their antibiotic resistance profiles. Samples were collected using sterile cotton swabs and then inoculated into brain heart infusion broth. Subsequent subcultures were performed on both blood and MacConkey agar. The isolates were then identified using the Bruker MALDI Biotyper (Bruker Daltonik, Bremen, Germany) to the species level. Sampling was conducted in various wards and in the hospital and the University areas on dispenser levers and nozzle areas. The results showed that all samples yielded one or more bacterial species. Bacterial isolates identified belonged to species commonly found on the skin microflora and some Gram-negative enteric bacilli. Higher colonization was observed on the dispenser lever. Among Gram⁺ microorganisms, most bacterial species were shown to be sensitive to β-lactams, with the exception of Staphylococcus spp., resistant to AMP (Ampicillin) and Penicillin. However, no Methicillin resistant isolates were detected. Gram⁻ microorganisms such as Pseudomonas luteola were shown to be sensitive to all tested antibiotics, while Pantoea agglomerans was shown to be resistant to AMC (amoxicillin–clavulanic acid). Rifampicin tested only against Bacilli showed resistance. Based on the findings, it is recommended to implement systematic cleaning and proper maintenance of manual dispenser areas or to use automated dispensers to reduce hand contact and minimize microbial contamination. Monitoring the presence of microorganisms in hand sanitizing gels and dispensers is an essential infection control strategy. Full article

Staphylococcus epidermidis (S. epidermidis) belongs to methicillin-resistant bacteria strains that cause severe disease in humans. Herein, molecularly imprinted polymer (MIP) nanoparticles resulting from solid-phase synthesis on entire cells were employed as a sensing material to identify the species. MIP nanoparticles revealed spherical shapes with diameters of approximately 70 nm to 200 nm in scanning electron microscopy (SEM), which atomic force microscopy (AFM) confirmed. The interaction between nanoparticles and bacteria was assessed using height image analysis in AFM. Selective binding between MIP nanoparticles and S. epidermidis leads to uneven surfaces on bacteria. The surface roughness of S. epidermidis cells was increased to approximately 6.3 ± 1.2 nm after binding to MIP nanoparticles from around 1 nm in the case of native cells. This binding behavior is selective: when exposing Escherichia coli and Bacillus subtilis to the same MIP nanoparticle solutions, one cannot observe binding. Fluorescence microscopy confirms both sensitivity and selectivity. Hence, the developed MIP nanoparticles are a promising approach to identify (pathogenic) bacteria species. Full article