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The effect of lemon, orange and bergamot essential oils and their components on the survival of Campylobacter jejuni , Escherichia coli O157, Listeria monocytogenes , Bacillus cereus and Staphylococcus aureus in vitro and in food systems
Author(s) -
Fisher K.,
Phillips C.A.
Publication year - 2006
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/j.1365-2672.2006.03035.x
Subject(s) - citral , linalool , listeria monocytogenes , bacillus cereus , biology , microbiology and biotechnology , staphylococcus aureus , citrus × sinensis , cereus , orange (colour) , food science , bacteria , essential oil , genetics
Aims: To investigate the effectiveness of oils and vapours of lemon ( Citrus limon ), sweet orange ( Citrus sinensis ) and bergamot ( Citrus bergamia ) and their components against a number of common foodborne pathogens. Methods and Results: The disc diffusion method was used to screen the oils and vapours against Listeria monocytogenes , Staphylococcus aureus , Bacillus cereus , Escherichia coli O157 and Campylobacter jejuni . The survival of each species, demonstrated to be susceptible in the in vitro studies, was tested on cabbage leaf for 60 s by direct contact and on chicken skin for 10 min by direct contact and 24 h by vapour. The results indicate that bergamot was the most inhibitory essential oil (EO) and citral and linalool mimicked its effect ( P > 0·001). Citral and linalool vapours produced 6 log reductions in L. monocytogenes , Staph. aureus and B. cereus populations on cabbage leaf after 8–10 h exposure but bergamot vapour exposure, while producing a similar reduction in L. monocytogenes and B. cereus populations, had no effect on Staph. aureus . Conclusions: Bergamot was the most effective of the oils tested and linalool the most effective anti‐bacterial component. Gram‐positive bacteria were more susceptible than Gram‐negative bacteria in vitro , although Camp. jejuni and E. coli O157 were inhibited by bergamot and linalool oils and by linalool vapour. All bacteria tested were less susceptible in food systems than in vitro . Of the Gram‐positive bacteria tested Staph. aureus was the least susceptible to both the oils and the components tested. Significance and Impact of the Study: Results suggest the possibility that citrus EOs, particularly bergamot, could be used as a way of combating the growth of common causes of food poisoning.