A wide variety of foods can be contaminated with Listeria species, especially L. monocytogenes. Ready-to-eat (RTE) foods are predominantly associated with human listeriosis caused by L. monocytogenes. Therefore, this study aimed to assess the presence of Listeria species in RTE foods and to characterize L. monocytogenes isolates by means of detection of virulence markers, serotypes and genetic relatedness. Of the 300 RTE food samples, 59 (19.7%) were positive for Listeria species: L. innocua (13.3%), L. monocytogenes (5%), L. welshimerii (2.3%), L. grayi subsp. murrayi (1.3%), L. grayi (1%), L. ivanovii (1%) and L. ivanovi subsp. londoniensis (0.3%). All L. monocytogenes isolates identified were positive for the actA, iap, inlA, inlB, inlC, inlJ, plcA and prfA virulence genes and biofilm. The isolates were serotyped as 1/2c (33.3%), 4b (26.7%), 1/2a (26.7%), 1/2b (6.7%) and 3c (6.7%) by the multiplex-PCR and agglutination methods. PCR-restriction fragment length polymorphism with AluI and MluCI resulted in three and two profiles, respectively. Pulsed-field gel electrophoresis differentiated the L. monocytogenes isolates into 15 ApaI and 12 AscI patterns. Antimicrobial resistance of all Listeria isolates was determined by the disk diffusion method. Most L. monocytogenes isolates were sensitive to antimicrobials used in the treatment of listeriosis. This study shows the presence of potential pathogenic and antimicrobial-resistant L. monocytogenes in RTE foods that may lead to consumer health risks.
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http://dx.doi.org/10.1093/femsle/fnaa006 | DOI Listing |
Front Microbiol
January 2025
College Food Science and Light Industry, Nanjing Tech University, Nanjing, China.
A colloidal gold immunochromatographic assay (ICA) based on a dual-antibody sandwich method was developed for the rapid and convenient detection of () antigens in the early stages of infection. Monoclonal antibodies designed as 5B3 targeting the conserved region of 56 kDa outer membrane protein in various strains of were generated through cell fusion and screening techniques and combined with previously prepared polyclonal antibodies as detection antibodies to establish the ICA. Colloidal gold and polyclonal antibody-colloidal gold complexes were synthesized under optimized conditions.
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January 2025
Department of Chemistry, College of Science, King Faisal University, Al-Ahsa 31982, Saudi Arabia. Electronic address:
The main objective of this study is to prepare sodium alginate (SA)-based biofilms incorporated with watercress oil (WCO) as an antimicrobial material for sustainable food packaging. The physicochemical, antioxidant, and antibacterial properties of the prepared bio-based films were investigated. The antioxidant activity showed a remarkable increase, with DPPH inhibition increasing from 13.
View Article and Find Full Text PDFACS Nano
January 2025
Institute of Nanobiomaterials and Immunology & Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation, School of Life Sciences, Taizhou University, Zhejiang Taizhou 318000, China.
Despite significant progress in cancer treatment, traditional therapies still face considerable challenges, including poor targeting, severe toxic side effects, and the development of resistance. Recent advances in biotechnology have revealed the potential of bacteria and their derivatives as drug delivery systems for tumor therapy by leveraging their biological properties. Engineered bacteria, including , , and , along with their derivatives─outer membrane vesicles (OMVs), bacterial ghosts (BGs), and bacterial spores (BSPs)─can be loaded with a variety of antitumor agents, enabling precise targeting and sustained drug release within the tumor microenvironment (TME).
View Article and Find Full Text PDFMicrobiome
January 2025
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
Background: Microbial spoilage in meat impedes the development of sustainable food systems. However, our understanding of the origin of spoilage microbes is limited. Here, we describe a detailed longitudinal study that assesses the microbial dynamics in a meat processing facility using high-throughput culture-dependent and culture-independent approaches to reveal the diversity, dispersal, persistence, and biofilm formation of spoilage-associated microbes.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China. Electronic address:
Cervical cancer is the fourth most common cancer and the fourth leading cause of cancer death in women. Effective treatment of cervical cancer is urgently needed. Tumor therapeutic vaccine is a research hotspot in tumor immunotherapy, and the tumor therapeutic vaccine based on attenuated live bacteria carrier has clinical application prospect because of its clear action site and high safety.
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