Influence of soil microbes on Escherichia coli O157:H7 survival in soil rinse and artificial soil

Aims This research investigated the influence of soil microbiota on Escherichia coli O157:H7 survival in soil rinse and artificial soil. Additionally, the influence of selected soil bacteria on E. coli O157:H7 in soil environments was determined. Methods and Results Escherichia coli O157:H7 counts (log CFU per ml or g −1 ) were determined by spread plating: (i) artificial soil amended with soil rinse (filter‐sterilized and unfiltered) at 30°C; (ii) unfiltered soil rinse (50 ml) treated with cycloheximide (200  μ g ml −1 ), vancomycin (40  μ g ml −1 ), heat (80°C, 15 min) and no treatment (control) for 7 days at 30°C and (iii) filtered soil rinse with selected soil bacterial isolates over 7 days. There was a significant difference ( P  = 0·027) in E .  coli O157:H7 counts after 35 days between artificial soils amended with filtered (4·45 ± 0·29) and non‐filtered (1·83 ± 0·33) soil rinse. There were significant differences ( P  < 0·05) in E. coli O157:H7 counts after 3 days of incubation between soil rinse treatments (heat (7·04 ± 0·03), cycloheximide (6·94 ± 0·05), vancomycin (4·26 ± 0·98) and control (5·00 ± 0·93)). Lastly, a significant difference ( P  < 0·05) in E. coli O157:H7 counts was observed after 3 days of incubation at 30°C in filtered soil rinse when incubated with Paenibacillus alvei versus other soil bacterial isolates evaluated. Conclusions Soil microbiota isolated from Florida sandy soil influenced E. coli O157:H7 survival. Specifically, P. alvei reduced E. coli O157:H7 by over 3 log CFU per ml after 3 days of incubation at 30°C in filtered soil rinse. Significance and Impact of the Study This research identified soil bacterial isolates that may reduce E. coli O157:H7 in the soil environment and be used in future biocontrol applications.