RT info:eu-repo/semantics/article
T1 Quantification of Total and Viable Cells and Determination of Serogroups and Antibiotic Resistance Patterns of Listeria monocytogenes in Chicken Meat from the North-Western Iberian Peninsula
A1 Rodríguez Melcón, Cristina
A1 Esteves, Alexandra
A1 Panera Martínez, Sarah
A1 Capita González, Rosa María
A1 Alonso Calleja, Carlos
A2 Nutricion y Bromatologia
K1 Tecnología de los alimentos
K1 Listeria monocytogenes
K1 Minced chicken
K1 q-PCR
K1 Viability
K1 Serogroups
K1 Aantimicrobial resistance
K1 Food microbiology
K1 Food safety
K1 2414.04 Bacteriología
K1 3309 Tecnología de Los Alimentos
AB [EN]Twenty samples of minced chicken meat procured from butcher’s shops in León (Spain; 10 samples) and Vila Real (Portugal; 10 samples) were analyzed. Microbial concentrations (log10 cfu/g) of 7.53 ± 1.02 (viable aerobic microbiota), 7.13 ± 1.07 (psychrotrophic microorganisms), and 4.23 ± 0.88 (enterobacteria) were found. The detection method described in the UNE-EN ISO 11290-1 standard (based on isolation from the chromogenic medium OCLA) with confirmation by the polymerase chain reaction (PCR; lmo1030) (OCLA–PCR), revealed Listeria monocytogenes in 14 samples (70.0% of the total), nine of Spanish origin and five of Portuguese (p > 0.05). The levels of viable and inactivated L. monocytogenes in the samples were determined with a q-PCR using propidium monoazide (PMAxx) as a viability marker. Seven samples tested positive both with the OCLA–PCR and with the q-PCR, with estimated concentrations of viable cells varying between 2.15 log10 cfu/g (detection limit) and 2.94 log10 cfu/g. Three samples tested negative both with the OCLA–PCR and with the q-PCR. Seven samples were positive with the OCLA–PCR, but negative with the q-PCR, and three samples tested negative with the OCLA–PCR and positive with the q-PCR. The percentage of viable cells relative to the total ranged between 2.4% and 86.0%. Seventy isolates of L. monocytogenes (five from each positive sample) were classified in PCR serogroups with a multiplex PCR assay. L. monocytogenes isolates belonged to serogroups IIa (52 isolates; 74.3%), IIc (7; 10.0%), IVa (2; 2.9%), and IVb (9; 12.9%). The susceptibility of the 70 isolates to 15 antibiotics of clinical interest was tested. The strains presented resistance to between three and eight antibiotics. The average number of resistances was greater (p < 0.001) among strains isolated from Spanish samples (6.20 ± 1.08), than in those from Portugal (5.00 ± 1.08). In both groups of strains, a prevalence of resistance higher than 95% was observed for oxacillin, cefoxitin, cefotaxime, and cefepime. The need to handle minced chicken meat correctly, taking care to cook it sufficiently and to avoid cross-contamination, so as to reduce the danger of listeriosis, is emphasized. A combination of culture-dependent and culture-independent methods offers complementary routes for the detection in food of the cells of L. monocytogenes in various different physiological states.
PB MDPI
LK https://hdl.handle.net/10612/20439
UL https://hdl.handle.net/10612/20439
NO Rodríguez Melcón, C., Esteves, A., Panera Martínez, S., Capita, R., & Alonso-Calleja, C. (2022). Quantification of Total and Viable Cells and Determination of Serogroups and Antibiotic Resistance Patterns of Listeria monocytogenes in Chicken Meat from the North-Western Iberian Peninsula. Antibiotics, 11(12), Article e1828. https://doi.org/10.3390/antibiotics11121828
DS BULERIA. Repositorio Institucional de la Universidad de León
RD Jul 11, 2024