RESUMEN
This study investigated the antiviral effects of floating electrode-dielectric barrier discharge (FE-DBD) plasma treatment (1.1 kV, 43 kHz, N2 1.5 m/s, 5-30 min) against human norovirus (HuNoV) GII.4 in Jogaejeotgal Infectivity was assessed using real-time quantitative-PCR (RT-qPCR) following treatment of samples with propidium monoazide (PMA) and sodium lauroyl sarcosinate (Sarkosyl). This study also investigated the effects of FE-DBD plasma treatment on Jogaejeotgal quality (assessed using pH value and Hunter colors). Following inoculation, the average titers of HuNoV GII.4 in Jogaejeotgal significantly (P < 0.05) decreased with increases in the FE-DBD plasma treatment time in both the non-PMA-treated and PMA + Sarkosyl-treated samples; in the non-PMA and PMA + Sarkosyl treated Jogaejeotgal, HuNoV GII.4 titers (log10 copy number/µL) were to: 3.16 and 2.95 (5 min), 2.90 and 2.48 (10 min), 2.82 and 2.40 (15 min), 2.58 and 2.26 (20 min), 2.48 and 2.06 (25 min), and 2.23 and 1.91 (30 min), respectively. The average titers of HuNoV demonstrated significant (P < 0.05) reductions of 0.35 log10 (55.3%) in PMA + Sarkosyl-treated samples compared with the non-PMA treated samples following exposure to 5-30 min of FE-DBD plasma. Reductions of >1-log for HuNoV in PMA + Sarkosyl- treated Jogaejeotgal required treatments of FE-DBD of 5-30 min. Using the first order kinetic model (R2 = 0.95), GII.4 decimal reduction time (D-value) resulting from FE-DBD plasma was 23.75 min. The pH and Hunter colors ("L", "a", and "b") were not significantly different (P > 0.05) between the untreated and FE-DBD plasma-treated Jogaejeotgal. Based on these results, the PMA + Sarkosyl/RT-qPCR method could be assessing HuNoV viability following 5-30 min treatment of FE-DBD plasma. Furthermore, may be an optimal treatment for Jogaejeotgal without altering the food quality (color and pH).
Asunto(s)
Bivalvos , Norovirus , Animales , Electrodos , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , República de CoreaRESUMEN
Members of the genus Weissella are mostly found in fermented plant material. Among the Weissella species, two species, Weissella thailandensis and Weissella jogaejeotgali, were isolated from foods fermented from marine animals. The two species showed a high level of 16S rRNA gene similarity (99.39â%), whereas they exhibited a moderate level of DNA-DNA hybridization relatedness (63.9â%) in an earlier study. In this study, we determined the whole genome sequence of W. thailandensis KCTC 3751T and compared it to those of W. jogaejeotgali FOL01T and other related species. The average nucleotide identity value between the type strains of W. thailandensis and W. jogaejeotgali was 96.4â%, which is clearly higher than the cut-off proposed for bacterial species. We, therefore, propose to reclassify W. jogaejeotgali as a later heterotypic synonym of W. thailandensis.
Asunto(s)
Alimentos Fermentados/microbiología , Filogenia , Weissella/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , TailandiaRESUMEN
Strain PFL01T was isolated from traditional Korean fermented clam, jogae-jeotgal, and characterized. The strain was a facultative anaerobic, Gram-stain-negative bacterium that was rod-shaped, motile and beige-pigmented. The phylogenetic sequence analysis based on the 16S rRNA gene from PFL01T revealed that it was closely related to Lelliottia nimipressuralis LMG 10245T and Lelliottia amnigena LMG 2784T with 99.3 and 99.3â% sequence identities, respectively. Multilocus sequence type analysis of concatenated partial aptD, gyrB, infB and rpoB gene sequences showed a clear distinction of strain PFL01T from its closest related type strains. The discrimination was also supported by unique repetitive extragenic palindromic PCR (Rep-PCR, ERIC-PCR) fingerprint patterns. In addition, results from average nucleotide identity analyses with other species were less than 85â%. vitek and API analyses revealed distinct characteristics from other species of Lelliottia. The cellular fatty acid profile of the strain consisted of C16â:â0, cyclo-C17â:â0, C16â:â1ω7c/C16â:â1ω6c and C18â:â1ω7c/C18â:â1ω6c as major components. The whole genome of PFL01T was 4.6 Mb with a G+C content of 55.3 mol%. Based on these results, strain PFL01T was classified as a novel species of the genus Lelliottia, for which the name Lelliottia jeotgali sp. nov. is proposed. The type strain in PFL01T (=KCCM 43247T=JCM 31901T).