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Colonization of the human and animal intestinal tract with potential pathogenic bacteria is correlated with the risk of contamination of food products. The current study analyzed the prevalence of and O157H7 in ground meat in Ilam, Iran. Both index organisms were identified following standard food microbiological methods. For , the susceptibility to vancomycin was tested, and PCR was used to check for the gene. was present in all 24 ground meat samples, with no O157H7 detected in samples. The analysis showed the presence of the gene in 5/24 vancomycin resistant enterococci. In conclusion, this study for the first time demonstrates the presence of vancomycin-resistant enterococci in ground meat in Iran. This observation warrants further epidemiologic investigation and should be followed up in the future.

Resistance to antibiotics is one of the most critical health problems in the world. Therefore, finding new treatment methods to be used as alternatives to antibiotics has become a priority for researchers. Similar to phages, certain products containing antimicrobial components, such as molasses, are widely used to eliminate resistant bacteria. Molasses has a strong antimicrobial effect on bacterial cells, and this effect is thought to be due to the breakdown of the cytoplasmic cell membrane and cell proteins of the polyphenols in molasses. In the present study, phage-molasses interactions were investigated to examine the effects of concomitant use. It was found that molasses samples increased the size of phage plaques by up to 3-fold, and MIC and 1/2 × MIC concentrations of molasses increased the burst size of phages. Although no synergistic effect was found between the phage and molasses, the antimicrobial activities of the components and the effect of molasses on phage activity were demonstrated.

Persisters are a form of dormancy in bacteria that provide temporary resistance to antibiotics. The following reports on the formation of Escherichia coli O157:H7 E318 type II persisters from a protracted (8 days) challenge with ampicillin. Escherichia  coli O157:H7 followed a multiphasic die-off pattern with an initial rapid decline (Phase I) of susceptible cells that transitioned to a slower rate representing tolerant cells (Phase II). After 24 h post-antibiotic challenge, the E. coli O157:H7 levels remained relatively constant at 2 log CFU/mL (Phase III), but became non-culturable within 8-days (Phase IV). The revival of persisters in Phase III could be achieved by the removal of antibiotic stress, although those in Phase IV required an extended incubation period or application of acid-shock. The carbon utilization profile of persister cells was less diverse compared with non-persisters, with only methyl pyruvate being utilized from the range tested. Inclusion of methyl pyruvate in tryptic soy agar revived non-cultural persisters, presumably by stimulating metabolism. The results suggest that persisters could be subdivided into culturable or non-culturable cells, with the former representing a transition state to the latter. The study provided insights into how to revive cells from dormancy to aid enumeration and control.