ISOLATION OF BDELLOVIBRIOS THAT PREY ON ESCHERICHIA-COLI O157 H7 AND SALMONELLA SPECIES AND APPLICATION FOR REMOVAL OF PREY FROM STAINLESS-STEEL SURFACES/

Predatory bacteria of the genus Bdellovibrio that prey upon Escherichi a coli O157:H7 and Salmonella species were isolated from soil and sava ge samples. Bdellovibrio isolates 45k (from soil) and 88e (from savage ) attacked and lysed the E. coli and Salmonella strains tested, with l og,, reductions ranging from 2.5 to 7.9 CFU/mL after 7h incubation, us ing a two-membered culture system. The predators showed activity again st the bacteria within the temperature range of 19 to 37C. Bdellovibri o isolate 45k reduced a population off. coli dried on stainless steel surfaces by 3.6 log(10) CFU/cm(2) following 24h contact time and at a 10:1 predator to prey ratio and was also effective in reducing the lev el of biofilm cells. Bdellovibrios can potentially be utilized for rem oval of bacteria from surfaces of food processing equipment and possib ly for controlling the growth of pathogenic and spoilage bacteria in f oods.