The emerging pathogenic multidrug-resistant yeast Candida auris is an important source of healthcare-associated infections and of growing global clinical concern. The ability of this organism to survive on surfaces and withstand environmental stressors creates a challenge for eradicating it from hospitals. A panel of C. auris clinical isolates was evaluated on different surface environments against the standard disinfectant sodium hypochlorite and high-level disinfectant peracetic acid. C. auris was shown to selectively tolerate clinically relevant concentrations of sodium hypochlorite and peracetic acid in a surface-dependent manner, which may explain its ability to successfully persist within the hospital environment.

Ninety-six-hour P. aeruginosa biofilm survives 5 min treatment with 2000 ppm of peracetic acid, which is the working concentration used in some endoscope washer-disinfectors. This implies that disinfection failure of flexible endoscopes might occur when biofilms build up in the lumens of endoscopes.

The persistence of microorganisms as biofilms on dry surfaces resistant to usual terminal cleaning methods may pose an additional risk of transmission of infections.In this study, the Centre for Disease Control (CDC) dry biofilm model (DBM) was adapted into a microtiter plate format (Model 1) and replicated to create a novel in vitro model that replicates conditions commonly encountered in the healthcare environment (Model 2). Biofilms of S. aureus grown in the two models were comparable to the biofilms of the CDC DBM in terms of recovered log 10 CFU/well. Assessment of antimicrobial tolerance of biofilms grown in the two models showedModel 2 a better model for biofilm formation. Confirmation of biofilms phenotype with an extracellular matrix deficient S. aureus suggested stress tolerance through a nonmatrix defined mechanism in organisms. This study highlights the importance of conditions maintained in bacterial growth as they affect biofilm phenotype and behaviour.

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Bacterial biofilms pose a significant burden in both healthcare and industrial environments. With the limited effectiveness of current biofilm control strategies, novel or 2 adjunctive methods in biofilm control are being actively pursued. Reported here, is the first 3 evidence of the application of nanovibrational stimulation ("nanokicking") to reduce the biofilm formation of Pseudomonas aeruginosa. Nanoscale vertical displacements (approximately 60 nm) were imposed on P. aeruginosa cultures, with a significant reduction in biomass formation observed at frequencies between 200 to 4000 Hz at 24 h. The optimal reduction of biofilm formation was observed at 1 kHz, with changes in the physical morphology of the biofilms. Scanning electron microscope imaging of control and biofilms formed under nanovibrational stimulation gave indication of a reduction in extracellular matrix (ECM). Quantification of the carbohydrate and protein components of the ECM was performed and showed a significant reduction at 24 h at 1 kHz frequency. To model the forces being exerted by nanovibrational stimulation, laser interferometry was performed to measure the amplitudes produced across the Petri dish surfaces. Estimated peak forces on each cell, associated with the nanovibrational stimulation technique, were calculated to be in the order of 10 pN during initial biofilm formation. This represents a potential method of controlling microbial biofilm formation in a number of important settings in industry and medical related processes.

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Background and Objective: The bio-preservation of food products using bacteriocin-producing lactic acid bacteria (BPLAB) isolated directly from fermented foods is an innovative approach in ensuring food safety for human health sustainably. This study was designed to isolate and identify BPLAB from zobo drinks and evaluate their antimicrobial effects on selected spoilage and pathogenic microorganisms in vitro. Materials and Methods: Lactic acid bacteria were isolated using bacteriological media, while agar diffusion bioassay was employed to screen bacteriocin or bacteriocin-like substances and their antimicrobial effect was tested on selected pathogens, namely Salmonella pullorum, Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli as indicator organisms. Results: A high pH value of 5.5 was recorded from the control sample (LAB) while high temperature and total titratable acid of 28EC and 0.62% were obtained from the ETF sample, respectively. Out of 14 lactic acid bacterial isolates, Lactobacillus minor and L. buchneri exhibited total inhibition while L. bifermentans and L. fructivorans exhibited no inhibition to the tested microorganisms. Varied antimicrobial susceptibility profiling for the indicator isolates was recorded. Conclusions: The potential of BPLAB to inhibit some pathogens suggest their potential use as bio-preservatives in foods. Hence, this study was performed to test for the antimicrobial ability of Lactobacillus isolated from zobo drinks against some selected pathogens.