title: Antibacterial activities of plant essential oils and their components against Escherichia coli O157:H7 and Salmonella enterica in apple juice.
abstract: We evaluated 17 plant essential oils and nine oil compounds for antibacterial activity against the foodborne pathogens Escherichia coli O157:H7 and Salmonella enterica in apple juices in a bactericidal assay in terms of % of the sample that resulted in a 50% decrease in the number of bacteria (BA(50)). The 10 compounds most active against E. coli (60 min BA(50) range in clear juice, 0.018-0.093%) were carvacrol, oregano oil, geraniol, eugenol, cinnamon leaf oil, citral, clove bud oil, lemongrass oil, cinnamon bark oil, and lemon oil. The corresponding compounds against S. enterica (BA(50) range, 0.0044-0.011%) were Melissa oil, carvacrol, oregano oil, terpeineol, geraniol, lemon oil, citral, lemongrass oil, cinnamon leaf oil, and linalool. The activity (i) was greater for S. enterica than for E. coli, (ii) increased with incubation temperature and storage time, and (iii) was not affected by the acidity of the juices. The antibacterial agents could be divided into two classes: fast-acting and slow-acting. High-performance liquid chromatography analysis showed that the bactericidal results are related to the composition of the oils. These studies provide information about new ways to protect apple juice and other foods against human pathogens.
authors.affiliation: Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 800 Buchanan Street, Albany, California 94710, USA. fried@pw.usda.gov
authors.forename: Mendel
authors.initials: M
authors.lastname: Friedman
authors.forename: Philip R
authors.initials: PR
authors.lastname: Henika
authors.forename: Carol E
authors.initials: CE
authors.lastname: Levin
authors.forename: Robert E
authors.initials: RE
authors.lastname: Mandrell
mesh_terms: D000171:Acrolein / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000032:analysis / Q000494:pharmacology*; D001628:Beverages / Q000382:microbiology*; D000081007:Cymenes; D019453:Escherichia coli O157 / Q000187:drug effects*; D005638:Fruit / Q000382:microbiology; D006863:Hydrogen-Ion Concentration; D027845:Malus / Q000382:microbiology*; D039821:Monoterpenes / Q000737:chemistry / Q000494:pharmacology; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology; D010938:Plant Oils / Q000737:chemistry / Q000494:pharmacology*; D019779:Salmonella enterica / Q000187:drug effects*; D012995:Solubility; D013696:Temperature; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D000081007:Cymenes; D039821:Monoterpenes; D009822:Oils, Volatile; D010938:Plant Oils; D000171:Acrolein; C073316:carvacrol; C012843:cinnamaldehyde