The in vitro antibacterial activity of the hydrosols of (distilled spice water) sixteen spices (anise, basil, cumin, dalamagia sage, dill, fennel, laurel, mint, oregano, pickling herb, rosemary, sage, summer savory, seafennel, sumac and black thyme) were tested on fifteen bacteria (Bacillus amyloliquefaciens ATCC 23842, B. brevis FMC 3, B. cereus FMC 19, B. subtilis var. niger ATCC 10, Enterobacter aerogenes CCM 2531, Escherichia coli ATCC 25922, E. coli O157:H7 ATCC 33150, Klebsiella pneumoniae FMC 5, Proteus vulgaris FMC 1, Salmonella enteritidis, S. gallinarum, S. typhimurium, Staphlococcus aureus ATCC 2392, S. aureus ATCC 28213, Yersinia enterocolitica ATCC 1501). The hydrosols of five spices (anise, cumin, oregano, summer savory and black thyme) had antibacterial activity against some of the test bacteria. Oregano and summer savory were effective against all bacteria during incubation. Anise, curnin and black thyme hydrosols were active against some bacteria, but not all. Consequently, it is likely that some edible plant hydrosols may be used as antimicrobial agents to prevent the deterioration of food products. The other hydrosols did not show activity against any of the all bacteria tested. (C) 2002 Elsevier Science Ltd. All rights reserved.