RESUMEN

This study aimed to evaluate the impact of cold plasma (0, 5, 10, or 15 min) on the techno-functional and sensory properties of whey dairy beverages added with xylooligosaccharide (XOS, 1.5% p/v). Untreated and pasteurized whey beverages were also evaluated. The products were evaluated for physicochemical characteristics, bioactive compounds, XOS stability, rheological properties, and sensory characteristics. Cold plasma and pasteurized products presented lower color intensity (L*=87.4-87.9, a*=-0.24- -0.60, b*=2.41-5.19), reduced consistency (K = 4.31-42.21 mPa.sn and N = 0.57-0.95), and similar apparent viscosity, XOS chemical stability, and sensory characteristics compared with the untreated product. However, the cold plasma-treated beverages presented lower heat load indicators (hydroxymethylfurfural [HMF] values of 1.91-2.10 µmol/L and whey protein nitrogen index [WPNI] of 6.09-6.66 µmol/L) and a higher concentration of bioactive compounds (antioxidant activity [5.31-9.30%], and inhibition of ACE [14.17-22.53%], α-amylase [18.52-25.67%] and α-glucosidase [22.50-27.50%] activities) than the pasteurized product, being the effects more pronounced for the higher exposure times. Overall, cold plasma has important advantages for the processing of whey beverages added with XOS.

Asunto(s)

Gases em Plasma , Suero Lácteo , Bebidas/análisis , Glucuronatos , Oligosacáridos , Proteína de Suero de Leche

RESUMEN

Seven genomes of Corynebacterium pseudotuberculosis biovar equi were sequenced on the Ion Torrent PGM platform, generating high-quality scaffolds over 2.35 Mbp. This bacterium is the causative agent of disease known as "pigeon fever" which commonly affects horses worldwide. The pangenome of biovar equi was calculated and two phylogenomic approaches were used to identify clustering patterns within Corynebacterium genus. Furthermore, other comparative analyses were performed including the prediction of genomic islands and prophages, and SNP-based phylogeny. In the phylogenomic tree, C. pseudotuberculosis was divided into two distinct clades, one formed by nitrate non-reducing species (biovar ovis) and another formed by nitrate-reducing species (biovar equi). In the latter group, the strains isolated from California were more related to each other, while the strains CIP 52.97 and 1/06-A formed the outermost clade of the biovar equi. A total of 1,355 core genes were identified, corresponding to 42.5% of the pangenome. This pangenome has one of the smallest core genomes described in the literature, suggesting a high genetic variability of biovar equi of C. pseudotuberculosis. The analysis of the similarity between the resistance islands identified a higher proximity between the strains that caused more severe infectious conditions (infection in the internal organs). Pathogenicity islands were largely conserved between strains. Several genes that modulate the pathogenicity of C. pseudotuberculosis were described including peptidases, recombination enzymes, micoside synthesis enzymes, bacteriocins with antimicrobial activity and several others. Finally, no genotypic differences were observed between the strains that caused the three different types of infection (external abscess formation, infection with abscess formation in the internal organs, and ulcerative lymphangitis). Instead, it was noted that there is a higher phenetic correlation between strains isolated at California compared to the other strains. Additionally, high variability of resistance islands suggests gene acquisition through several events of horizontal gene transfer.

Asunto(s)

Infecciones por Corynebacterium/genética , Corynebacterium pseudotuberculosis/genética , Genoma Bacteriano/genética , Enfermedades de los Caballos/genética , Rhodococcus equi/genética , Animales , Infecciones por Corynebacterium/microbiología , Corynebacterium pseudotuberculosis/patogenicidad , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedades de los Caballos/microbiología , Caballos/microbiología , Filogenia , Polimorfismo de Nucleótido Simple/genética , Rhodococcus equi/patogenicidad

RESUMEN

Corynebacterium pseudotuberculosis causes significant loss to goat and sheep farmers because it is the causal agent of the infectious disease caseous lymphadenitis, which may lead to outcomes ranging from skin injury to animal death (Ruiz et al., 2011) [1]. This bacterium was grown under osmotic (2 M), acid (pH) and heat (50 °C) stress and under control (Normal-BHI brain heart infusion) conditions, which simulate the conditions faced by the bacteria during the infectious process. Subsequently, cDNA of each condition was sequenced by the SOLiD3 Plus platform using the RNA-Seq technique [2], [3], [4]. The data produced was processed to evaluate the differential gene expression, which is helpful to understand the adaptation mechanisms during the infection in the host. The sequencing data of all conditions are available in the European Bioinformatics Institute (EBI) repository under accession number E-MTAB-2017.

RESUMEN

The genome of Corynebacterium pseudotuberculosis MB20 bv. equi was sequenced using the Ion Personal Genome Machine (PGM) platform, and showed a size of 2,363,089 bp, with 2,365 coding sequences and a GC content of 52.1%. These results will serve as a basis for further studies on the pathogenicity of C. pseudotuberculosis bv. equi.