Antibacterial activity of plants used in cooking for aroma and taste.

Thirty-three plants used in cooking for aroma and taste were examined for antibacterial activity against pathogens causing foodborne infections. Vibrio parahaemolyticus and Staphylococcus aureus were sensitive to many kinds of plant extracts, whereas Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella Enteritidis populations decreased in only six, one, and three plant extracts, respectively. The polyphenol content in the plants was significantly different between the antibacterial plants and nonantibacterial plants, indicating that the polyphenols were related to the antibacterial action of these plants. Antibacterial activity of various concentrations of leaf extracts from Japanese persimmon, white cedar, and grape were investigated. Japanese persimmon and white cedar leaf extracts at low concentrations affected L. monocytogenes and V. parahaemolyticus rapidly. With grape leaf extract at low concentrations, the population of L. monocytogenes decreased similarly to Japanese persimmon and white cedar leaves. This study demonstrates that many plants used in cooking for aroma and taste contain polyphenols and exhibit antibacterial activity against foodborne pathogens.