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  • Management of Pocket Clinical Devices by Nurses: determinant factors and microbiological assessment
    Publication . Graveto, João; Costa, P.; Albano, Helena; Santos, C.; Fernandes, E.; Osório, N.; Oliveira, V.
  • Production of antilisterial bacteriocin by Pediococcus acidilactici HA‑6111‑2 under different stress conditions
    Publication . Engelhardt, Tekla; Albano, Helena; Kiskó, Gabriella; Mohácsi-Farkas, Csilla; Teixeira, Paula
  • Evaluation of a bacteriocinogenic Lactobacillus plantarum strain on the microbiological characteristics of “Alheira de Vitela”
    Publication . Macieira, Ariana; Albano, Helena; Pinto, Miguel; Linheiro, Raquel; Barbosa, Joana; Teixeira, Paula
    Lactic Acid Bacteria (LAB) and their bacteriocins can be successfully used as natural preservatives in meat products. This work aimed to investigate the effect of fresh and lyophilized starter cultures of an autochthonous bacteriocinogenic LAB strain (Lactobacillus plantarum ST153Ch: bac + culture) on the microbiological characteristics of “Alheira”, a traditional Portuguese smoked product. “Alheira” with the addition of fresh or lyophilized culture (ca. 108 cfu/g) and “Alheira” control (no bacteriocinogenic culture added) were produced by an industrial meat company. The antilisterial activity of this culture in this food matrix was investigated, with some samples being inoculated with Listeria monocytogenes (ca. 105 cfu/g). Detection of L. monocytogenes, Salmonella spp., sulphite reducing clostridia, Yersinia enterocolitica and enumeration of L. monocytogenes, Staphylococcus aureus, Bacillus cereus, Escherichia coli, Enterobacteriaceae, lactic acid bacteria, yeasts and moulds were performed immediately after production and at 3, 7, 15, 21, 28, 60 and 90 days of storage at 4 ℃, according to ISO methodologies. Also, a 16S rRNA Gene Analysis was performed of the microbial communities of “Alheira” with and without the lyophilized bacteriocinogenic culture. Pathogenic and indicator organisms were not detected or were below acceptable levels in all samples. LAB counts increased during storage and reached similar values after 15 days (ca. 1010 cfu/g) in all samples. There was a clear trend for a higher reduction of L. monocytogenes in the presence of the bioprotective culture, more pronounced during the initial 15 days of storage. From the analysis of the microbial communities of samples of “Alheiras” at different stages of fermentation, Leuconostocaceae and Lactobacillaceae predominated in all the samples and Lactobacillus was the genus more prevalent in “Alheiras” after 60 days of storage with the addition of bacteriocinogenic culture.
  • Production of LAB bacteriocin in MRS medium and in a natural cereal medium with potential application in the food industry
    Publication . Macieira, Ariana; Maciel, Claudia; Albano, Helena; Morais, Alcina M M B; Teixeira, Paula
  • Characterization of a lactiplantibacillus plantarum r23 isolated from arugula by whole-genome sequencing and its bacteriocin production ability
    Publication . Barbosa, Joana; Albano, Helena; Silva, Beatriz; Almeida, Maria Helena; Nogueira, Teresa; Teixeira, Paula
    Lactiplantibacillus plantarum is one of the lactic acid bacteria species most used as probiotics and starter cultures in food production. Bacteriocin-producers Lpb. plantarum are also promising natural food preservatives. This study aimed to characterize Lpb. plantarum R23 and its bacteriocins (R23 bacteriocins). The genome sequence of Lpb. plantarum R23 was obtained by whole-genome sequencing (WGS) in an Illumina NovaSeq platform. The activity of Lpb. plantarum R23-produced bacteriocin against two Listeria monocytogenes strains (L7946 and L7947) was evaluated, and its molecular size was determined by tricine-SDS-PAGE. No virulence or antibiotic resistance genes were detected. Four 100% identical proteins to the class II bacteriocins (Plantaricin E, Plantaricin F, Pedi-ocin PA-1 (Pediocin AcH), and Coagulin A) were found by WGS analysis. The small (<6.5 kDa) R23 bacteriocins were stable at different pH values (ranging from 2 to 8), temperatures (between 4 and 100 °C), detergents (all, except Triton X-100 and Triton X-114 at 0.01 g/mL), and enzymes (catalase and α-amylase), did not adsorb to the producer cells, had a bacteriostatic mode of action and their maximum activity (AU/mL = 12,800) against two L. monocytogenes strains occurred between 15 and 21 h of Lpb. plantarum R23 growth. Lactiplantibacillus plantarum R23 showed to be a promising bio-preservative culture because, besides being safe, it produces a stable bacteriocin or bacteriocins (har-bors genes encoding for the production of four) inhibiting pathogens as L. monocytogenes. Further studies in different food matrices are required to confirm this hypothesis and its suitability as a future starter culture.
  • Hand hygiene management among nurses: collective health challenges
    Publication . Graveto, João; Santos, Cristina; Costa, Paulo Santos; Fernandes, Elisabete; Alarico, Susana; Osório, Nádia; Albano, Helena; Oliveira, Vânia
    Objective: To describe the determining factors in hand hygiene management among nurses and identify associated collective health challenges. Method: Cross-sectional descriptive study. Data were collected using a questionnaire that was applied in four internal medicine units of a hospital of reference in Portugal. Results: The sample was composed of 50 nurses aged 26 to 55 years (mean age of 34.88 years); 80% were women, 58% had a Bachelor’s degree, and had 5-30 years of nursing practice (X̄ =11.94;±5.92). The vast majority of nurses (90%) reported complying with the existing recommendations on hand hygiene in pre-established moments. However, none of the nurses were able to identify all the moments for hand hygiene using water and soap or alcohol-based handrub. Conclusion: This study shows that continuous training, adequate materials/structures in the units, and redesigned administration/supervision practices are determining factors to achieve higher levels of adherence to hand hygiene among nurses, as well as increased quality and safety in care delivery, which is a current collective health challenge. Descriptors: Health Services Administration; Hand Hygiene; Nurses; Infection Control; Public Health Nursing
  • Are nurses uniforms a reservoir for Methicillin-resistant Staphylococcus aureus? Lessons to be learned from Portugal
    Publication . Fernandes, E.; Costa, P.; Graveto, J.; Santos, C.; Osório, N.; Alarico, S.; Albano, Helena
  • Microbiological contamination of reusable plastic bags for food transportation
    Publication . Barbosa, J.; Albano, H.; Silva, C. P.; Teixeira, P.
    Nowadays, with so many concerns for the environment, the use of reusable plastic bags is becoming routine, instead of the use of polluting single-use plastic bags. However, this is controversial in terms of food safety, since consumers transport many different foods, which could contaminate their bags and pose a risk to their health due to cross-contamination. This study aimed to detect or enumerate several indicators/pathogens from 30 used reusable plastic (polypropylene) bags and, to evaluate their antibiotic resistance profiles after identification by 16s rRNA of each isolated microorganism. Several genera of Enterobacteriaceae, coagulase-negative staphylococci and also Listeria monocytogenes were found in the reusable plastic bags analyzed. In general, high percentages of antibiotics resistance were found, highlighting the elevated occurrence of multi-resistant isolates of coagulase-negative staphylococci and Enterobacteriaceae. This study demonstrates the level and variety of microbial contamination of some used reusable plastic bags. No correlation was found between microbial levels and the visual appearance of each bag demonstrating that appearance is not a reliable datum about the bag contamination. We believe that this study could help the competent authorities taking measures to alert consumers to good food safety practices, not only in their kitchens, but also in the bags that carry their food.