Bactericidal Activities of Plant Essential Oils and Some of Their Isolated Constituents against Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, and Salmonella enterica

Abstract

An improved method of sample preparation was used in a microplate assay to evaluate the bactericidal activity levels of 96 essential oils and 23 oil compounds against Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica obtained from food and clinical sources. Bactericidal activity (BA50) was defined as the percentage of the sample in the assay mixture that resulted in a 50% decrease in CFU relative to a buffer control. Twenty-seven oils and 12 compounds were active against all four species of bacteria. The oils that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.009) were marigold, ginger root, jasmine, patchouli, gardenia, cedarwood, carrot seed, celery seed, mugwort, spikenard, and orange bitter oils; those that were most active against E. coli (with BA50 values ranging from 0.046 to 0.14) were oregano, thyme, cinnamon, palmarosa, bay leaf, clove bud, lemon grass, and allspice oils; those that were most active against L monocytogenes (with BA50 values ranging from 0.057 to 0.092) were gardenia, cedarwood, bay leaf, clove bud, oregano, cinnamon, allspice, thyme, and patchouli oils; and those that were most active against S. enterica (with BA50 values ranging from 0.045 to 0.14) were thyme, oregano, cinnamon, clove bud, allspice, bay leaf, palmarosa, and marjoram oils. The oil compounds that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.034) were cinnamaldehyde, estragole, carvacrol, benzaldehyde, citral, thymol, eugenol, perillaldehyde, carvone R, and geranyl acetate; those that were most active against E. coli (with BA50 values ranging from 0.057 to 0.28) were carvacrol, cinnamaldehyde, thymol, eugenol, salicylaldehyde, geraniol, isoeugenol, citral, perillaldehyde, and estragole; those that were most active against L monocytogenes (with BA50 values ranging from 0.019 to 0.43) were cinnamaldehyde, eugenol, thymol, carvacrol, citral, geraniol, perillaldehyde, carvone S, estragole, and salicylaldehyde; and those that were most active against S. enterica (with BA50 values ranging from 0.034 to 0.21) were thymol, cinnamaldehyde, carvacrol, eugenol, salicylaldehyde, geraniol, isoeugenol, terpineol, perillaldehyde, and estragole. The possible significance of these results with regard to food microbiology is discussed.

Óleo essencial de orégano: interferência da composição química na atividade frente a Salmonella Enteritidis

“…Esses compostos se acumulam na bicamada lipídica causando desarranjo na função e na estrutura da membrana e penetram a célula bacteriana, exercendo atividade inibitória no citoplasma celular, provocando lise e liberação do ATP intracelular (WALSH et al, 2003). Outro mecanismo documentado é a perda de constituintes celulares pelo aumento da permeabilidade da membrana citoplasmática (Smith-Palmer;STEWART;FYFE, 1998;CONSENTINO et al, 1999;POL;SMID, 1999;FRIEDMAN;HENIKA;MANDRELL, 2002;Rhayour et al, 2003;YUSTE;FUNG, 2003, NAZER et al, 2005.…”

Antimicrobial activity of essential oils against Vancomycin-Resistant enterococci (VRE) and Escherichia coli O157:H7 in feta soft cheese and minced beef meat

“…The demand for safe foods, coupled with the preference by consumers for foods free of synthetic additives, has increased the interest for natural preservatives in recent years (27 (3,8,10,12,13,16,22). However, the information of their effect in actual food systems is still insufficient.…”

Cytotoxic, anti-carcinogenic and antioxidant properties of the most frequent plant volatiles

“…EOs exhibit inhibiting activity against a wide spectrum of bacteria [17] and are very useful mainly in the clinical practice and food industry. In vitro studies of Friedman et al [18] demonstrated bactericidal activity of different EOs at levels between 0.2 and 10 µl/ml against Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica, Salmonella typhimurium, Shigella dysenteria, Bacillus cereus and Staphylococcus aureus.…”