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There are a number of reports indicating correlation between outbreaks of campylobacteriosis and the consumption of raw vegetables. This study is a meta-analysis on the prevalence of Campylobacter in fresh vegetables and fruits without any location limitation, which was performed through a documented review of the available resources. Relevant literature was reviewed by trained reviewers, who examined the results for the inclusion of articles in the meta-analysis. The prevalence of Campylobacter in raw vegetables, the sample source, the Campylobacter species, and the method of detection were extracted. The prevalence of Campylobacter in vegetables, fruits, and fresh produce were estimated to be 0.53%. Analysis of the various sample groups initially showed that the bean and sprouts group was the vegetable with the highest prevalence of Campylobacter (11.08%). The rate of contamination was higher when both the molecular and conventional methods were employed. The highest prevalence of Campylobacter was found in Asia (33.4%). Despite the low prevalence, consumption of raw vegetables is inherently risky because no treatment is used to inactivate the pathogens. Therefore, proper sanitation methods are recommended to treat the raw products.

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Identification of the most proteolytic Pseudomonas strains that can produce heat-resistant proteases and contribute to the Ultra High Temperature (UHT) milk destabilization is of great interest. In the present study, among the 146 Pseudomonas isolates that encoded the aprX gene, five isolates with the highest proteolytic activity were selected and identified based on 16S rRNA, rpoD and gyrB gene sequences data. The identification results were confirmed by phylogenetic analysis based on multilocus sequence analysis and identified the representative isolates as P. jessenii (two isolates) and P. gessardii (three isolates). Casein zymography demonstrated the ability of these species to produce heat-resistant enzymes, AprX, with molecular mass of about 48 kDa during storage at 7° C for 72 h. In sterilized milk samples, the residual activity of AprX caused a considerable enhancement in the degree of protein hydrolysis, non-protein nitrogen and non-casein nitrogen contents of the samples during a two-month storage. This enhancement was slightly higher in samples containing enzyme produced by P. jessenii compared to P. gessardii ones, resulting in earlier onset of sterilized milk destabilization. Hence, this study revealed that P. jessenii and P. gessardii can play a considerable role in deterioration of Iranian commercial long-life milk.

Background: Escherichia coli O157:H7 (EHEC) has been traditionally associated with foodborne infections from consumption of foods with animal origin such as ground beef and burgers. Objectives: The objective of this study was to investigate the contamination of fresh ground beef with non-sorbitol fermenting Escherichia coli and presence of virulence genes in isolates obtained from butchers located in Ahvaz, Iran. Materials and Methods: A total of 200 fresh ground beef were sampled during a six-month period. All samples were enriched in Tryptic Soy Broth (TSB) with novobiocin and plating on Cefixime Telluride-Sorbitol MacConkey (CT-SMAC). The suspected colonies were subjected to Polymerase Chain Reaction (PCR) analysis to identify virulence genes containing rfbE O157, flic H7, stx1 and stx2 genes. Results: Overall, 1.5% of ground beef samples were contaminated with the O157 E. coli strain meanwhile 1% of samples contained the O157:H7 strain and 0.5% of samples had the O157:H7 with virulent stx1 and stx2 genes. Conclusions:The observed results indicated the necessity of good care in abattoir, butcheries and during food distribution, mainly ground beef. Also, a zero tolerance policy could be useful to control E. coli O157 in meat products nationwide.