Presence of enterotoxigenic Staphylococcus aureus in artisan fruit salads in the city of San Luis, Argentina

Abstract

An increase in the consumption of fruit juices and minimally processed fruits salads has been observed in recent years all over the world. In this work, the microbiological quality of artisan fruit salads was analysed. Faecal coliforms, Salmonella spp, Shigella spp, Yersinia enterocolitica and Escherichia coli O157:H7 were not detected; nevertheless, eleven strains of Staphylococcus aureus were isolated. By multiplex PCR, all isolates showed positive results for S. aureus 16S rRNA gene and 63.6% of them were positive for sea gene. Furthermore, PCR sea positive strains were able to produce the corresponding enterotoxin. Finally, the inactivation of these strains in fruit salads by nisin, lysozyme and EDTA, was studied. EDTA produced a total S. aureus growth inhibition after 60 h of incubation at a concentration of 250 mg/L. The presence of S. aureus might indicate inadequate hygiene conditions during salad elaboration; however, the enterotoxigenicity of the strains isolated in this study, highlights the risk of consumers’ intoxication. EDTA could be used to inhibit the growth of S. aureus in artisan fruit salads and extend the shelf life of these products.

Microbiological Safety of Street-Vended Beverages in Chow Kit, Kuala Lumpur

“…Fruits that are often used to produce juices do not involve heat-processing and do not contain preservatives. Therefore, these fruits are easily infected by bacteria and fungi [33]. Other sources of contamination of S. aureus in fruit juices include equipment used during beverage handling and fruit juice processing as reported by Chong et al [18] who found the presence of Staphylococcus species on fruit juice extractors as well as utensils used to cut the fruit, which contributed to the contamination of the produced fruit juices.…”

Antimicrobial Activity of Lactic Acid Bacteria Starters against Acid Tolerant, Antibiotic Resistant, and Potentially VirulentE. coliIsolated from a Fermented Sorghum-Millet Beverage

“…Recently, Byakika et al [1] reported the presence of presumptive E. coli in Obushera (pH ≤ 4.0 and titratable acidity � 0.1-3.1%). Indeed, several reports of undesirable microorganisms in various acidic foods exist [7][8][9][10][11].…”