Antibacterial Activity of Carum copticum Essential Oil Against Escherichia Coli O157:H7 in Meat: Stx Genes Expression

The present study was carried out to determine, for the first time, the chemical composition and antibacterial activity of essential oils derived from the aerial parts of three aromatic plants Thymus algeriensis Boiss & Reut, Rosmarinus officinalis L., and Salvia officinalis L. growing under semiarid conditions. The essential oils were chemically analyzed and identified by gas chromatography (GC) and GC/ mass spectrometry (GC/MS) and their antimicrobial activity was individually evaluated against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using both agar disk diffusion and agar dilution methods. The major constituents of Thymus algeriensis essential oil were identified as camphor (13.62%), 1,8-cineol (6.00%), borneol (5.74%), viridiflorol (4.00%), and linalool (3.93%). For Rosmarinus officinalis essential oil, 48 compounds were characterized, of which the main constituents were camphor (17.09%), Z-β-ocimene (10.88%), isoborneol (9.68%), α-bisabolol (7.89%), and borneol (5.11%). While, Salvia officinalis essential oil was characterized by β-thujone (16.44%), followed by viridiflorol (10.93%), camphor (8.99%), 1,8-cineol (8.11%), trans-caryophyllene (5.85%), and α-humulene (4.69%) as the major components. Notably, results from antibacterial screening indicated that Thymus algeriensis and Salvia officinalis essential oils exhibited a strong inhibitory effect against both Escherichia coli and Staphylococcus aureus compared to Rosmarinus officinalis essential oil. Further, less activity was recorded against Pseudomonas aeruginosa for the three tested essential oils.

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Potential Application of Ziziphora Clinopodioides Essential Oil and Nisin as Natural Preservatives Against Bacillus Cereus and Escherichia Coli O157: H7 in Commercial Barley Soup

Journal of Food Safety ◽

10.1111/jfs.12257 ◽

2016 ◽

Vol 36 (4) ◽

pp. 435-441 ◽

Cited By ~ 17

Author(s):

Yasser Shahbazi ◽

Nassim Shavisi ◽

Ehsan Mohebi

Keyword(s):

Escherichia Coli ◽

Essential Oil ◽

Bacillus Cereus ◽

Potential Application ◽

Escherichia Coli O157 ◽

Natural Preservatives

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Growth Inhibition of Escherichia coli O157:H7 and Listeria monocytogenes by Carvacrol and Eugenol Encapsulated in Surfactant Micelles

Journal of Food Protection ◽

10.4315/0362-028x-68.12.2559 ◽

2005 ◽

Vol 68 (12) ◽

pp. 2559-2566 ◽

Cited By ~ 92

Author(s):

SYLVIA GAYSINSKY ◽

P. MICHAEL DAVIDSON ◽

BARRY D. BRUCE ◽

JOCHEN WEISS

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Listeria Monocytogenes ◽

Essential Oil ◽

Growth Inhibition ◽

Surfactant Concentration ◽

Escherichia Coli O157 ◽

Surfactant Micelles ◽

E Coli ◽

Oil Components

Growth inhibition of four strains of Escherichia coli O157:H7 (H1730, F4546, 932, and E0019) and Listeria monocytogenes (Scott A, 101, 108, and 310) by essential oil components (carvacrol and eugenol) solubilized in nonionic surfactant micelles (Surfynol 465 and 485W) was investigated. Concentrations of encapsulated essential oil components ranged from 0.02 to 1.25% depending on compound, surfactant type, and surfactant concentration (0.5 to 5%). Eugenol encapsulated in Surfynol 485W micelles was most efficient in inhibiting growth of the pathogens; 1% Surfynol 485W and 0.15% eugenol was sufficient to inhibit growth of all strains of E. coli O157:H7 and three of four strains of L. monocytogenes (Scott A, 310, and 108). The fourth strain, L. monocytogenes 101, was inhibited by 2.5% Surfynol and 0.225% eugenol. One percent Surfynol 485W in combination with 0.025% carvacrol was effective in inhibiting three of four strains of E. coli O157:H7. Strain H1730 was the most resistant strain, requiring 0.3% carvacrol and 5% surfactant for complete inhibition. Growth inhibition of L. monocytogenes by combinations of carvacrol and Surfynol 465 ranged between 0.15 and 0.35% and 1 and 3.75%, respectively. Generally, the antimicrobial activity of Surfynol 465 in combination with eugenol was higher than that for the combination with carvacrol. The potent activity was attributed to increased solubility of essential oil components in the aqueous phase due to the presence of surfactants and improved interactions of antimicrobials with microorganisms.

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Effect of Gamma Radiation and Oregano Essential Oil on Murein and ATP Concentration of Escherichia coli O157:H7

Journal of Food Protection ◽

10.4315/0362-028x-68.12.2571 ◽

2005 ◽

Vol 68 (12) ◽

pp. 2571-2579 ◽

Cited By ~ 24

Author(s):

STÉPHANE CAILLET ◽

FRANÇOIS SHARECK ◽

MONIQUE LACROIX

Keyword(s):

Escherichia Coli ◽

Essential Oil ◽

Gamma Radiation ◽

Cell Damage ◽

Wall Structure ◽

High Dose ◽

Escherichia Coli O157 ◽

Oregano Essential Oil ◽

Intracellular Atp ◽

Oregano Oil

This study was carried out to evaluate the effects of gamma radiation alone or in combination with oregano essential oil on the murein composition of Escherichia coli O157:H7 and on the intracellular and extracellular concentrations of ATP. The bacterial strain was treated with three radiation doses: 0.4 kGy to induce cell damage, 1.1 kGy to obtain a viable but nonculturable state, and 1.3 kGy to cause cell death. Oregano essential oil was used at 0.006 and 0.025% (wt/vol), which is the MIC. All treatments had a significant effect (P ≤ 0.05) on the murein composition, although some muropeptides did not seem to be affected by the treatment. Each treatment had a different effect on the relative percentage and number of muropeptides. There was a significant correlation (P ≤ 0.05) between the decrease in intracellular ATP and the increase in extracellular ATP following treatment of the cells with oregano oil. The reduction of intracellular ATP was even more important when oregano oil was combined with irradiation, but irradiation alone at a high dose (≤1.1 kGy) significantly decreased (P ≤ 0.05) the internal ATP without affecting the external ATP. Transmission electron microscopic examination revealed that oregano oil and irradiation have an effect on cell wall structure.

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