Browsing by Subject "Foodborne pathogens"

Sort by: Order: Results:

Now showing items 1-4 of 4
  • Osemwowa, Etinosa; Omoruyi, Iyekhoetin Matthew; Kurittu, Paula; Heikinheimo, Annamari; Fredriksson-Ahomaa, Maria (2021)
    Beef can easily be contaminated with bacteria during the meat production chain. In this work, we studied the contamination levels of mesophilic aerobic bacteria (MAB) and thermotolerant coliform bacteria (TCB) on raw beef surfaces from small shops in Helsinki, Finland and meat markets in Benin City, Nigeria. We also investigated the prevalence of Salmonella, Campylobacter, Yersinia, Shiga toxin-producing Escherichia coli (STEC), Listeria, and cephalosporin-resistant E. coli (CREC). In total, one hundred unpacked raw beef samples from Finland and Nigeria were collected in 2019. The median MAB and TCB counts were significantly (P < 0.001) higher on beef from Nigeria than from Finland. The median MAB and TCB counts in Nigeria were 7.5 and 4.0 log10 cfu/cm2, respectively, and 6.5 and 2.8 log10 cfu/cm2 in Finland, respectively. Most (94%) Nigerian samples were unacceptable according to limits set by the EU. Beef samples from meat markets in Benin City were significantly (P < 0.05) more frequently contaminated with Salmonella, STEC, and CREC than beef samples from small shops in Helsinki. Salmonella, STEC, and CREC were isolated from 30, 36, and 96% of Nigerian samples, respectively, and from
  • Fredriksson-Ahomaa, Maria; London, Laura; Skrzypczak, Teresa; Kantala, Tuija; Laamanen, Ilona; Bistrom, Mia; Maunula, Leena; Gadd, Tuija (2020)
    The northern European wild boar population has increased during the last decade. Highest wild boar numbers in Finland have been reported in the southeastern part near the Russian border. Wild boars may be infected with several human and animal pathogens. In this study, we investigated the presence of important foodborne pathogens in wild boars hunted in 2016 in Finland using serology, PCR and culturing. Seroprevalence of Salmonella (38%) and Yersinia (56%) infections was high in wild boars. Antibodies to hepatitis E virus, Toxoplasma gondii and Brucella were found in 18%, 9% and 9% of the wild boars, respectively. Trichinella antibodies were detected in 1% of the animals. We recorded no differences in the seroprevalence between males and females. However, Yersinia and T. gondii antibodies were detected significantly more often in adults than in young individuals. Listeria monocytogenes (48%) and stx-positive Escherichia coli (33%) determinants were frequently detected in the visceral organs (spleen and kidneys) by PCR. Yersinia pseudotuberculosis O:1 and L. monocytogenes 2a and 4b were identified by culturing from the PCR-positive samples. Brucella suis biovar 2 was isolated from visceral organs. No African swine fever, classical swine fever or Aujeszky's disease were detected in the wild boars. Our study shows that wild boars are important reservoirs of foodborne pathogens.
  • Ran, Li; Yassami, Shiva; Kiviniemi, Eero Antero; Qiao, Wanjin; Takala, Timo; Saris, Per (2021)
    In this work, we studied the control of Listeria monocytogenes in raw chicken meat by marinating breast strips with beer containing bacteriocin leucocin C. An URA3 auxotrophic strain of probiotic yeast Saccharomyces boulardii CNCM I-745 was used as a host to express the gene lecC encoding the bacteriocin leucocin C. Secretion of leucocin C was confirmed by the inhibition against L. monocytogenes using agar well diffusion assay. The new auxotrophic host secreted leucocin C better than previously constructed wild-type strain, and therefore it was used to brew anti-listerial beer. The beer was shown to maintain its anti-listerial activity for 38 days. Chicken breast strips spiked with L. monocytogenes were then marinated with the anti-listerial beer for overnight, and the killing of L. monocytogenes was analysed. Marination with beer containing leucocin C reduced the viable cells of L. monocytogenes by about 1.6 log from (2.2 +/- 0.6) x 10(7) CFU/g on day 24, and 2.2 log from (1.8 +/- 0.3) x 10(5) CFU/g on day 38. In conclusion, the URA3 auxotrophic S. boulardii efficiently secreted the bacteriocin leucocin C, and brewing beer with this strain resulted in anti-listerial beer. Such beer is effective as a marinade in reducing the Listeria risk in chicken breast strips.
  • Wirtanen, Gun (Turun ammattikorkeakoulu, 2018)
    Reports from Turku University of Applied Sciences
    see the attached pdf-file