Efflux pump inhibitors may inhibit the major AcrAB-TolC in Salmonella efflux systems which are the major efflux pumps responsible for multidrug resistance in Gram-negative clinical isolates.

The presented results suggest the potential application of EOs against infections, caused by biofilm-producing K. pneumoniae, to prevent biofilm formation or decrease their resistance threshold. Moreover, the combination of EOs with ciprofloxacin minimizes the antibiotic concentration used and accordingly the potential accompanying toxic side effects.

Background: Carbapenem antibiotics consider the primary treatment choice for serious Pseudomonas aeruginosa infection. Hence, the evolution of carbapenem resistance mediated by acquiring genes encoding class b enzymes is of global concern. The purpose of this article research is to explore the prevalence, drug resistance profiles, and metallo-βlactamases (MβLs) production in extensively drug-resistant carbapenem-resistant P. aeruginosa (XDR-CRPA). Methods: P. aeruginosa isolates were collected and identified according to conventional methods. Antibiotic resistance patterns were determined by single disk diffusion. Minimum inhibitory concentrations (MICs) of (imipenem, meropenem, ceftazidime, piperacillin/tazobactam, levofloxacin, and gentamicin) were determined for CRPA. A subset of the isolates collection consisting of the XDR-CRPA with the highest MICs to imipenem and meropenem were selected for the phenotypic screening of carbapenemases and MβLs production capability using the modified carbapenem inactivation (mCIM) and imipenem-EDTA combined disk (MβL-CD) methods, respectively. Then, molecular analysis, including identification by the specific primer of 16S rRNA and detection of MβL genes using polymerase chain reaction (PCR) was performed to the XDR selected isolates. Results: Among 100 P. aeruginosa isolated throughout this period, 59% exhibited reduced susceptibility rates to carbapenems. A total of 20.3% and 57% of CRPA isolates were MDR and XDR, respectively. MIC values of the CRPA revealed that these isolates exhibited high MIC 50 and MIC 90 to the six selected antibiotics. The findings of the (mCIM) assay displayed identical concordance results with the MβL-CD. Molecular investigation technique assured that 10 (90.9%) and 2 (18.1%) of the 11 XDR selected isolates are positive for bla NDM-1 and bla VIM-1 genes, respectively. Polymyxin B and colistin followed by aztreonam were the most effective antibiotics used for curing infections caused by XDR Pseudomonas aeruginosa. Conclusion: The prevalence of high XDR-CRPA in our study is a critical problem. Our present study found that the bla NDM-1 was present at a significant frequency among the selected XDR isolates, highlighting the need for establishing strict antimicrobial policies to avoid the prompt spread of these isolates.

The emergence of multi-drug-resistant (MDR) pathogenic bacteria is considered as a global problem. The aim of this study was to evaluate the antimicrobial inhibitory effects of the oily aqueous extract of Moringa peregrina Forssk against MDR clinical Salmonella enterica isolates. Four MDR S. enterica isolates were proved to have a gene mutation in amino acids codon 83 and 87 of gyrA and 67, 76 and 80 of parC gene by polymerase chain reaction (PCR) amplification and sequencing. The active components of M. pregrina extract were purified using GLC and TLC techniques and by using IR, NMR and mass spectra. The M. peregrina Forssk extract effect on bacterial cells was determined using scanning and transmission electron microscopies. Results demonstrated that M. peregrina Forssk have an excellent inhibitory effect against 34 MDR S. enterica isolates with different minimum inhibitory concentration (MIC) (109.37-437.5 mg/mL). The active component was identified as oleic acid-3 hydroxy propyl ester. The main abnormalities of Salmonella cells were observeddestruction in the cell wall that led to a reduction of protoplast besides, disruption of cytoplasmic membranes and, consequently, loss in their metabolic functions and death. This is the first report that deeply highlights the antimicrobial activity of M. peregrina Forssk against MDR clinical S. enterica isolates.

Determination of the rHLB of Garlic and Eruca oils allows the ease of preparation of stable, consistent, and non-irritant cream.

A total of 300 human fecal samples were collected from febrile neutropenic patients suffering from severe gastroenteritis, followed by identification and serological characterization of recovered isolates. Fifty nontyphoidal Salmonella (NTS) serovars were recovered. A total of serologically identified 50 NTS serovars recovered from poultry of the same geographical area and during the same period as well as one standard strain S. Poona were supplied by the Bacterial Bank of Animal Health Research Institute of Egypt. Antibiogram analysis revealed that the human and poultry serovars exhibited similar antimicrobial resistance patterns against 28 different antimicrobial agents, particularly against ampicillin, cefotaxime, oxytetracycline, and erythromycin. Plasmids harboring blaCTX-m, blaSHV, blaTEM, and aac(6’)-Ib were detected in 11 (22%) and 8 (16%) of human and poultry serovars, respectively. Molecular detection of the most clinically relevant virulence genes and analysis of the associated virulence genotypes proved that the human (n = 11) and poultry serovars (n = 12) shared 11 genotypes. Enterobacterial repetitive intergenic consensus PCR analysis revealed that human and poultry serovars were clustered together in 3 out of the 4 clusters with a similarity index ranged from 0.15 to 1. Since poultry are usually consumed by humans, the presence of resistant bacteria harboring transmissible genetic elements is of great health concern.

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The use and manufacturing of silver nanoparticles (AgNPs) have recently received considerable attention in many fields. Methicillin resistant Staphylococcus aureus (MRSA) causes infectious diseases in humans. Therefore, the aim of this work was to bio-synthesize AgNPs using the cyanobacteria Phormidium sp. extract and to use this extract with AgNPs to kill MRSA. Extracellular bio-formation of AgNPs by Phormidium sp. was scrutinized at various pH points and temperatures. Then, characterization and assessment of the antimicrobial power of the produced particles were performed. Extract and extract + AgNPs were screened using Fourier Transform Infra-Red (FT-IR) spectroscopy and electron microscopy. The manufacturing and fastness of AgNPs were monitored visually (by color change) and spectroscopically. FT-IR analysis uncovered the biomolecules in the extract that caused the reduction of silver ions, protected them from aggregation and supplied them with high stability. Results indicated that AgNPs are spheres of 9 nm diameter. AgNPs combined with the extract proved to be a powerful antibacterial factor against MRSA. Consequently, biosynthesis of silver nano-spheres using Phormidium sp. with high antagonistic potency against MRSA is considered as an eco-friendly, time-saving strategy and with potential medicinal significance.