Fighting Microbial Infections from Escherichia coli O157:H7: The Combined Use of Three Essential Oils of the Cymbopogon Genus and a Derivative of Esculentin-1a Peptide.
Raffaella ScottiBruno CasciaroAnnarita StringaroFilippo MaggiMarisa ColoneRoberta GabbianelliPublished in: Antibiotics (Basel, Switzerland) (2024)
The absence of effective therapy against Escherichia coli O157:H7 infections has led to the need to develop new antimicrobial agents. As the use of synergistic combinations of natural antimicrobial compounds is growing as a new weapon in the fight against multidrug-resistant bacteria, here, we have tested new synergistic combinations of natural agents. Notably, we investigated a possible synergistic effect of combinations of essential oils and natural peptides to counteract the formation of biofilm. We chose three essential oils (i.e., Cymbopogon citratus , C. flexuosus and C. martinii ) and one peptide already studied in our previous works. We determined the fractional inhibitory concentration (FIC) by analyzing the combination of the peptide derived from esculentin-1a, Esc(1-21), with the three essential oils. We also studied the effects of combinations by time-kill curves, scanning electron microscopy on biofilm and Sytox Green on cell membrane permeability. Finally, we analyzed the expression of different genes implicated in motility, biofilm formation and stress responses. The results showed a different pattern of gene expression in bacteria treated with the mixtures compared to those treated with the peptide or the single C. citratus essential oil. In conclusion, we demonstrated that the three essential oils used in combination with the peptide showed synergy against the E. coli O157:H7, proving attractive as an alternative strategy against E. coli pathogen infections.
Keyphrases
- biofilm formation
- escherichia coli
- staphylococcus aureus
- candida albicans
- pseudomonas aeruginosa
- essential oil
- gene expression
- electron microscopy
- multidrug resistant
- klebsiella pneumoniae
- cancer therapy
- dna methylation
- poor prognosis
- bone marrow
- acinetobacter baumannii
- high resolution
- binding protein
- ionic liquid
- atomic force microscopy
- genome wide analysis
- long non coding rna