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Streptococcus agalactiae (S. agalactiae) is a pathogen causing bovine mastitis that results in considerable economic losses in the livestock sector. To understand the distribution and drug resistance characteristics of S. agalactiae from dairy cow mastitis cases in China, multilocus sequence typing (MLST) was carried out and the serotypes and drug resistance characteristics of the bacteria in the region were analysed.

Streptococcus agalactiae is an important zoonotic pathogen that affects milk production and quality and poses a threat to public health. Treatment of infections with this bacterium exploits antimicrobials, to which the resistance of S. agalactiae is a growing problem. Addressing the possibility of a correlation between this pathogen’s genetic factors for antimicrobial resistance and virulence, this study attempted to identify the relevant genes.

Active peptides in mare milk have unique biological activities, but how the bioactive protein in mare's milk changes under the influence of temperature has not been fully studied. Therefore, in this study, the differential expression of bioactive peptides potentially present in horse milk under different heat treatment conditions was investigated for the first time using peptidomic and bioinformatic techniques. We collected a total of 15 samples. In this study, we divided the samples into five groups, specifically, 65 °C, 30 min; 72 °C, 15 min; 83 °C; 10 min; 95 °C, 5 min; and an untreated group as a control, which involved four different temperature treatments, in order to understand changes in bioactive peptides and to identify the sequence of bioactive peptides. In the experiment, a total of 2341 active peptides were identified. The amino acid composition of the potential active peptides remained stable across different temperatures, but their abundance varied with temperature. In all, 23 peptides from 20 different proteins were identified, with the highest number of active peptides identified at 72 °C. Through database searches, we found that a majority of these peptides were within β-lactoglobulin and immunoglobulin domain proteins, which are known for their potential biological activities. These findings provide a theoretical foundation for the development of peptides with different bioactivities as potential functional foods. [ABSTRACT FROM AUTHOR]

The authentication of milk and dairy products has great significance for food fraud. The present investigation entailed the development of a novel method that amalgamates the double-tube approach with multiplex real-time polymerase chain reaction (PCR) technology, incorporating TaqMan probes, to facilitate the high-throughput screening and detection of animal-derived constituents within milk and dairy products. Eight dairy-derived animal-specific primers and probes were designed for the mitochondrial cytochrome b (Cytb) gene of eight dairy products, including cow, buffalo, yak, goat, sheep, horse, donkey, and camel. Through the developed double-tube detection assays, the above eight targets could be simultaneously identified with a detection limit of 0.00128–0.0064 ng/μL. The multiplex qPCR assay was effectively validated using simulated adulterated samples with different mixing ratios and demonstrated a detection limit of 0.1%. Upon analysis of 54 commercially available dairy products, a mislabeling rate of 33% was revealed. This method affords an efficacious means of detecting dairy product ingredients, thereby offering robust technical backing for market oversight and regulatory enforcement of milk and dairy products. [ABSTRACT FROM AUTHOR]

It is well known that excessive levels of sulfur dioxide and its derivatives are connected to diverse diseases. Therefore, developing highly sensitive probes to detect and monitor sulfite in living cells is important for the diagnosis of disease and the study of biochemical processes in vivo. In this report, two zero cross-talk ratiometric fluorescent probes were synthesized (CA-ID-MC and CA-BI-MC), which were derived from carbazole-indolenine w-conjugated system for effective detection of sulfite in living cells. Observably, CA-BI-MC exhibited the largest emission shift of 157 nm from 617 to 460 nm with the addition of various concentrations of sulfite, which is beneficial for high-resolution imaging of the sulfite. CA-BI-MC also exhibits high sensitivity and low cytotoxicity. More importantly, this probe successfully located mitochondria and sensed the sulfite in HeLa cells caused by exogenous stimulation. Key words: zero cross-talk, bisulphite, mitochondria targeted, fluorescent probe. Il est bien connu que des concentrations excessives de dioxyde de soufre et de ses derives sont associees a diverses maladies. Afin de permettre le diagnostic et l'etude des processus biochimiques in vivo de ces maladies, il est donc important de mettre au point des sondes tres sensibles pour la detection des sulfites et la surveillance de leurs concentrations dans les cellules vivantes. Dans cet article, nous presentons la synthese de deux sondes fluorescentes ratiometriques a diaphonie nulle (CA-ID-MC et CA-BI-MC) dont le systeme a conjugaison [PI] derive de la carbazole-indolenine permet la detection efficace des sulfites dans les cellules vivantes. Visiblement, la sonde CA-BI-MC a revele le plus grand deplacement de longueur d'onde d'emission, soit 157 nm, passant de 617 a 460 nm consecutivement a l'ajout de sulfite a diverses concentrations, un resultat prometteur pour l'imagerie a haute resolution des sulfites. La sonde CA-BI-MC a egalement montre une sensibilite elevee, ainsi qu'une cytotoxicite faible. Fait plus important encore, cette sonde est parvenue a localiser les mitochondries et a detecter la formation de sulfites provoquee par stimulation exogene dans les cellules HeLa. [Traduit par la Redaction] Mots-cles: diaphonie nulle, bisulfite, a cible mitochondriale, sonde fluorescente., Introduction Sulfite is an indispensable additive in many food products, because it inhibits the development of both enzymatic and nonenzymatic browning in a variety of processing or storage situations and [...]