In Vitro Susceptibility of Multidrug Resistant Strains of Salmonella to Essential Oils

Abstract

Antimicrobial resistance has become a global threat to public health. There is a critical need to find new antimicrobial substances from natural sources. The aim of this study was to investigate the antimicrobial activity of essential oils (EOs) obtained from Origanum vulgare, Thymus serpyllum, Thymus vulgaris, and Melaleuca alternifolia against multidrug resistant strains of Salmonella isolated from samples of diverse animal origin. The strains were biochemically identified, serotyped, and characterized for their antimicrobial resistance profiles. The antimicrobial activity of the EOs against the strains was evaluated using the Kirby-Bauer diffusion method, followed by determination of the minimal inhibitory concentration and minimum bactericidal concentrations. The EOs of T. serpyllum and O. vulgare, which contain carvacrol as the main compound, show excellent antimicrobial activity.

Differential Effects of Dietary Oregano Essential Oil on the Inflammation Related Gene Expression in Peripheral Blood Mononuclear Cells From Outdoor and Indoor Reared Pigs

“…Among essential oils, oregano essential oil (ORE) is used in the pig industry for its beneficial effects, ranging from improved performance to increased pork quality ( 31 , 32 ). It has been shown that oregano has anti-inflammatory and antimicrobial effects ( 33 – 35 ), by modulating the cytokine levels and immunity-related transcription factors ( 36 , 37 ). In addition, oregano stimulates digestion with effects on enterocytes, by accelerating their renewal rate, improving their capacity for nutrient absorption, and reducing pathogen contamination ( 38 ).…”

Evaluation of the antibacterial, modulatory and anti-adherent properties of oregano (Origanum vulgare) essential oil against food pathogenic bacteria

“…The microdilution method in 96-well plates revealed MIC and MBC values of 0.156 and 0.3125 μg mL -1 , respectively. Another investigation assessed the antibacterial activity of oregano oil using both disk diffusion and broth microdilution techniques against 25 strains of Salmonella isolated from turkey, chicken, calf burgers, and wild boar liver (Listorti et al, 2020). Inhibition zones ranging from 10.3 to 23.3 mm in diameter were observed, along with MIC and MBC values ranging from 0.012 to 0.2 %v/v (Listorti et al, 2020).…”

Isolation and Molecular Identification of Avian Pathogenic Escherichia coli in Broiler Chickens Suffering from Colibacillosis in some Governorates in Egypt

“…Moreover, organo essential oil act as anti-inflammatory by inhibiting the inflammatory biomarkers levels; monocyte chemoattractan protein-1 (MCP-1), the vascular cell adhesion molecule-1 (VCAM-1) and the intracellular cell adhesion molecule-1 (ICAM-1) (MCP-1, VCAM-1 and ICAM-1), and decrease synthesis of cytokines; tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, IL-1β, and IL-6 and Increased synthesis of cytokine IL-10 [22]. So, oregano has antiinflammatory and antimicrobial effects [52], by modulating the cytokine levels and immunityrelated transcription factors [28]. Also, carvacrol reduces the severity of inflammation by the production of mediators of inflammation and protein concentration as well as the gene expression modulation of interleukins [53].…”