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.

Escherichia coli is a common cause of mastitis in dairy cows, which results in large economic losses to the livestock industry. The aim of this study was to investigate the prevalence of E. coli in raw milk in China, assess antimicrobial drug susceptibility, and identify key antibiotic resistance genes carried by the isolates. In total, 350 raw milk samples were collected from large-scale farms in 16 provinces and cities in six regions of China to assess the resistance of E. coli isolates to 14 antimicrobial drugs. Among the isolates, nine resistance genes were detected. Of 81 E. coli isolates (23.1%) from 350 raw milk samples, 27 (33.3%) were multidrug resistant. Antimicrobial susceptibility testing showed that the 81 E. coli isolates were resistant to 13 (92.9%) of the 14 antibiotics, but not meropenem. The resistance gene blaTEM was highly distributed among the 27 multidrug-resistant isolates with a detection rate of 92.6%. All isolates carried at least one resistance gene, and 19 patterns of resistance gene combinations with different numbers of genes were identified. The most common gene combinations were the one-gene pattern blaTEM and the three-gene pattern blaTEM-blaPSE-blaOXA. The isolation rate of E. coli in raw milk and the identified resistance genes provide a theoretical basis for the rational use of antibiotics by clinical veterinarians.

Amino acids play a dual role in milk protein synthesis, functioning as both metabolic precursors and signaling molecules. This study aimed to elucidate the molecular mechanism by which glycine regulates α-casein production in bovine mammary epithelial cells (MAC-T). Under serum-free conditions, MAC-T cells were exposed to graded concentrations of glycine (1.105, 2.209, 4.418, 8.836, 17.673, and 35.345 mM) for 24 h. α-Casein levels in cell lysates and culture supernatants were quantified by ELISA. Transcriptional activity of casein-encoding genes (CSN1S1, CSN1S2) and PI3K-AKT-mTOR pathway components was assessed by RT-qPCR. Phosphorylation status of pathway proteins was analyzed by Western blot. The functional involvement of the PI3K-AKT-mTOR pathway was validated using the specific inhibitor LY294002. Glycine stimulated α-casein synthesis and secretion in a concentration-dependent manner, with maximal efficacy at 4.418 mM. At this concentration, glycine upregulated CSN1S1, CSN1S2, and PI3K-AKT-mTOR pathway gene expression, and enhanced phosphorylation of the corresponding proteins. Inhibition of PI3K-AKT-mTOR signaling by LY294002 abolished glycine-induced α-casein synthesis, and this effect was reversed by glycine co-treatment. These findings demonstrate that glycine enhances α-casein synthesis through activation of the PI3K-AKT-mTOR pathway.

The aroma of camel milk is a key sensory indicator for evaluating its quality and flavor. Camel milk collected at different lactation stages exhibits unique flavor characteristics. However, no systematic study has yet explored the aroma characteristics and variation patterns of camel milk across these stages. This study employs HS-SPME-GC-MS, multivariate statistical analysis, and metagenomics to systematically reveal differences in aroma formation in camel milk across lactation periods and their interactions with microbial communities. A total of 577 metabolites is detected. Through OPLS-DA screening, 24 key differential flavor compounds are identified. ROAV analysis indicates that 2,4-undecadienal and (E)-2-undecenal are the main contributors to the fatty, creamy, fresh green, and citrus aromas of camel milk. Some compounds are more abundant in colostrum, while others are richer in mature milk. For microbiota, colostrum is dominated by Proteobacteria, Psychrobacter, and Janthinobacterium, whereas mature milk is dominated by Acinetobacter and Moraxella. Mature milk shows significantly higher alpha diversity and species richness. Spearman correlation analysis shows that core bacterial groups such as Enterococcus and Lactococcus are significantly positively correlated with characteristic flavor compounds, including aldehydes and lactones. This finding suggests that HS-SPME-GC-MS, combined with multivariate analysis, effectively distinguishes patterns associated with microbes and flavor metabolites in camel milk at different lactation stages, which provides a theoretical basis for quality control and further processing of camel milk.

Raw milk quality serves as a pivotal determinant throughout the dairy production and processing chain, given that bacterial abundance and diversity exert direct effects on product safety and shelf life. This study employed single-molecule real-time (SMRT) sequencing to profile how production environments shape the microbial community structure of raw camel milk in the Altay and Hami regions of Xinjiang. The dominant phyla across all samples were Firmicutes (43.04%), Proteobacteria (21.98%), Actinobacteriota (16.40%), Bacteroidota (10.61%), and Cyanobacteria (7.91%). Functional profiling revealed that Clusters of Orthologous Groups (COG)-encoded proteins were predominantly enriched in metabolic pathways, particularly amino acid transport and energy conversion. These findings establish a robust scientific foundation for refining raw milk production protocols. Notably, environmental sourcing analysis identified feces and soil as primary reservoirs for key taxa, providing actionable evidence for upgrading quality surveillance systems and optimizing production practices in the camel milk industry.

Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a complex and debilitating disorder with limited treatment options. Camel milk (CM), known for its rich nutrients and anti-fatigue properties, may offer multi-target benefits for managing this condition. This study utilized an integrated approach combining metabolomics, network pharmacology, and animal experiments. CM metabolites were profiled and screened via ADME. Potential targets were predicted and intersected with CFS/ME-associated genes. Male BALB/c mice were subjected to chronic restraint and forced swimming to evaluate the effects of CM (1000 mg/kg) on behavioral, inflammatory, neuroendocrine, and metabolic parameters. CM administration significantly improved exhaustive swimming time and reduced immobility. It attenuated systemic inflammation (restored IL-10), normalized brain CREB and DRD2/OPRM1 mRNA, and enhanced skeletal muscle AKT/GLUT4 expression and glycogen levels. Camel milk alleviates CFS/ME symptoms through the multi-component, multi-target regulation of neuroendocrine, inflammatory, and energy metabolism pathways. These preclinical findings suggest that CM may have potential as a supportive nutritional intervention for alleviating chronic fatigue, pending validation in human studies.