Activity of Brassica oleracea leaf juice on foodborne pathogenic bacteria.
Many vegetables of the Cruciferae family have been found to possess antimicrobial properties against several microorganisms of clinical importance. In this study, we reported the antibacterial effect of Brassica oleracea juice on several food-borne pathogens. The juice was found to be effective in inhibiting the growth of Salmonella Enteritidis, verotoxigenic Escherichia coli O157:H7, E. coli HB producing thermolabile toxin, nontoxigenic E. coli, and Listeria monocytogenes, but not Enterococcus faecalis. All cauliflower cultivars tested suppressed bacterial growth in a dose-dependent manner after 5 h of treatments, and the reduction in the number of viable cells ranged from 1 log with a 10% juice concentration to more than 3 log with a 20% juice concentration. The foodborne bacteria tested were also markedly reduced by isothiocyanates, natural components abundant in the genus Brassica, indicating that glucosinolate-derived isothiocyanates can play a major role in the antimicrobial activity of cauliflower. The antimicrobial effect of juice was reduced in presence of cysteine, suggesting that one mechanism of action of the juice involves blocking bacterial sulfhydryl groups.
Brandi
Giorgio
G
Istituto di Scienze Tossicologiche Igienistiche e Ambientali, Università degli Studi di Urbino Carlo Bo, Urbino, Italy. brandi@uniurb.it
Amagliani
Giulia
G
Schiavano
Giuditta F
GF
De Santi
Mauro
M
Sisti
Maurizio
M
D001937:Brassica / Q000737:chemistry*; D015169:Colony Count, Microbial; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D008089:Listeria monocytogenes / Q000187:drug effects / Q000254:growth & development; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D012477:Salmonella enteritidis / Q000187:drug effects / Q000254:growth & development
D010936:Plant Extracts