Clostridium difficile: prevalence in foods and study of alternative treatments to conventional therapeutics applied on C. difficile infection

Funder

Organizational Unit

Publications

Hygiene Indicators and Salmonellae on Surfaces of Swine Carcasses from Two Slaughterhouses in Northern Portugal

Publication . Moura-Alves, Márcio; Carvalho, Marta; Baggio Ribeiro, Deise Helena; Barbosa, Joana; Silveira, Leonor; Pista, Ângela; Pinto, Helena Patrícia; Saraiva, Cristina; Teixeira, Paula; Esteves, Alexandra

Abstract: The monitoring of carcass surface contamination along the slaughter line enables verification of slaughter operation hygiene and the use of good manufacturing practices. Pork meat is a common source of human nontyphoidal salmonellosis, one of the most frequently reported foodborne illnesses worldwide. This study was conducted to gather data on microbial loads before and after evisceration on the surfaces of swine carcasses in two slaughterhouses. The presence of Salmonella enterica was evaluated only after evisceration on carcass surfaces and in livers and floor drains (environmental samples) because pigs are common carriers of this pathogen. The contamination of carcass surfaces was evaluated by delimitation of surface area with sterilized templates (100 cm2), and surface samples were collected with gauze swabs. Total aerobic mesophilic bacteria, Enterobacteriaceae, and Escherichia coli were enumerated. Significant differences (P < 0.05) in counts of mesophilic bacteria, Enterobacteriaceae, and E. coli were found on the external carcass surfaces, with higher counts after evisceration. The neck and abdominal areas had higher levels of mesophilic bacteria, Enterobacteriaceae, and E. coli and a high prevalence of Salmonella. Salmonella was detected in only one of the studied slaughterhouses; 19 (7.3%) of 259 analyzed carcass samples were positive for Salmonella, and Salmonella was detected in two livers and two floor drains. A total of 52 Salmonella isolates (44 from carcasses, 5 from livers, and 3 from drains) were recovered. Three Salmonella serovars (Typhimurium 4,5:i- , Wernigerone, and Derby) were identified, and 53.8% of the 52 isolates were multidrug resistant. The results reveal the need for continuous improvement of slaughtering operations and implementation of good manufacturing practices to ensure the safety of pork produced in Portugal.

2022-11-01Journal article

Restricted access

Screening of Bacteriocinogenic Lactic Acid Bacteria and Their Characterization as Potential Probiotics

Publication . Pinto, Ana; Barbosa, Joana; Albano, Helena; Isidro, Joana; Teixeira, Paula

Probiotics are living microorganisms used as nutritional additives that confer health benefits on the host. Their use in food products is very attractive, especially if they could also inhibit important foodborne pathogens. In this study, antimicrobial activity against several foodborne pathogens was screened for 280 lactic acid bacteria (LAB) isolated from different food products and the probiotic characteristics of bacteriocinogenic isolates were evaluated. Seven out of 280 LAB isolates were selected due to their bacteriocinogenic properties and identified by 16S rRNA gene sequence analysis as Pediococcuspentosaceus (n = 6) and Lactobacillus plantarum (n = 1). Virulence factors and antibiotic resistances were not detected for any of the isolates. Except for L. plantarum R23, all the isolates were able to survive through the simulated gastrointestinal tract conditions. Only P.pentosaceus CFF4 was able to adhere to Caco-2 cells after the simulated gastrointestinal tract passage. In conclusion, even though in vivo studies should be performed, P.pentosaceus CFF4, which was also able to inhibit the growth of foodborne pathogens in vitro, seems to be a potential probiotic to be used in the food industry.

2020-03-11Journal article

Open access