The present study is an overview of the role of vegetables as a transmission vehicle of Salmonella in Mexico. One hundred samples of each of 17 different vegetables were analyzed during a period of 18 months. Salmonella was isolated from 98 samples. Salmonella enterica serovar Typhimurium was isolated from the highest percentage of samples with typeable Salmonella isolates (23.9%), followed by S. enterica subsp. arizonae and Salmonella Choleraesuis each from 16.9%, Salmonella Gallinarum from 11.1%, Salmonella Anatum and S. enterica subsp. houtenae each from 9.7%, Salmonella Agona and Salmonella Edinburg each from 4.22%, Salmonella Enteritidis and S. enterica subsp. salamae each from 2.81%, and Salmonella Bongor, Salmonella Pullorum, Salmonella Typhi, and Salmonella C1 flagellar b each from 1.4%. Of the isolated bacteria, 27.6% were nontypeable strains. Salmonella was isolated from 12% of parsley samples, 11% of cilantro samples, 9% of broccoli samples, 9% of cauliflower samples, 9% of “papaloquelite” (Por...

We analyzed the presence of Listeria spp. in oyster, fish, and seawater samples and tested isolates for antibiotic sensitivity. Listeria monocytogenes was found in 4.5% of fish samples and 8.3% of seawater samples and was not recovered from oysters. Multiresistant environmental strains were found, representing a potential threat to human health.

Bacteriocins are considered promising natural biopreservatives in the food industry because of their broad spectrum of antimicrobial activity against Gram-positive bacteria and foodborne pathogens. This review provides information on several bacteriocins (nisin, pediocin, Micocin®, lacticin 3147, and enterocin AS-48), their mechanisms of action, applications, and discussion of regulatory requirements for their approval as food additives by the Food and Drug Administration (FDA) and the European Union to improve food safety. Nisin (the most studied bacteriocin), recognized as generally regarded as safe by the FDA, is used as a food preservative. Pediocin, derived from Pediococcus acidilactici, shows efficacy against Listeria species and is used in vegetable and meat products. Micocin®, a mixture of bacteriocins produced by Carnobacterium maltaromaticum CB1, is effective against Clostridium botulinum and Listeria monocytogenes. Lacticin 3147, composed of two peptides: Ltnα and Ltnβ, shows synergistic antibacterial activity with potential applications in the control of pathogens in dairy products. Enterococcin AS-48, produced by Enterococcus faecalis subsp. liquefaciens S-48, exhibits broad-spectrum antimicrobial activity against several Gram-positive bacteria and has been studied for biopreservation in a number of food products. For regulatory approval, the following criteria must be met: determination of identity, chemical composition, safety assessments, and recommended concentrations for use. Despite the difficulties posed by their large-scale production and purification, bacteriocins hold enormous potential for improving food safety and shelf life; however, further research is required to harness bacteriocins as future food preservation strategies

The thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) are the main virulence factors of Vibrio parahaemolyticus . We isolated V. parahaemolyticus from seawater, fish, and oysters obtained from the Pueblo Viejo Lagoon in Veracruz, determined the serogroups, phenotypically and genotypically characterized TDH and TRH, and investigated the presence of the toxR gene. A total of 46 V. parahaemolyticus strains were isolated, and all of them amplified the 368-bp toxR gene fragment. The trh gene was not identified in any of the strains; 4 of the 46 strains were Kanagawa phenomenon (KP) positive and amplified the 251-bp tdh gene fragment. The most frequent serogroup was serogroup O3. This is the first report of the presence of KP-positive tdh -positive environmental V. parahaemolyticus strains in Mexico.