Plant extracellular vesicles (P-EVs) are considered promising functional food ingredients due to their various health benefits. In this study, blueberry extracellular vesicles (B-EVs) were collected and purified by size exclusion chromatography (SEC). The chemical compounds in B-EV extracts were analyzed by LC-MS/MS. In addition, the stability of B-EVs was evaluated during short- and long-term storage, heating, and in vitro digestion. The results showed that the B-EVs had a desirable particle size (88.2 ± 7.7 nm). Protein and total RNA concentrations were 582 ± 11.2 μg/mL and 15.4 μg/mL, respectively. The optimal storage temperatures for B-EVs were 4 °C and −80 °C for short- and long-term storage, respectively. Fluorescent labeling and qRT-PCR tests showed that B-EVs could be specifically internalized by Caco-2 cells, whereas virtually no cytotoxic or growth-inhibitory effects were observed. B-EVs down-regulated the expression levels of IL-1β and IL-8 and up-regulated the expression levels of NF-κβ and TLR5 in Caco-2 cells. Overall, the results proved that the intact structure of B-EVs could be preserved during food storage and processing conditions. B-EVs had the ability to reach the human intestine through oral delivery. Moreover, they could be absorbed by intestinal cells and affect human intestinal function.

The cage-free system has gained a lot of interest in recent years because it can offer chickens more freedom and is easier to manage compared with free-range rearing systems, but few studies have focused on the effect of the cage-free rearing system on meat quality and flavor. In this study, 44 Jianghan chickens were reared in caged or cage-free systems to explore the effect of different rearing systems on meat-eating quality. Sensory evaluation of cooked muscles showed that the leg muscle aroma, juiciness, and flavor intensity significantly improved by the cage-free rearing. The cage-free hens had significantly lower body weight, abdominal fat percentage, and meat fat content, but higher meat moisture content. The cage-free group had brighter breast muscle and redder leg muscle color 24 h after slaughter. Transcriptomic and metabolomic profile analysis of the leg muscle samples showed that the cage-free rearing changed biosynthesis pathways associated with glycogen metabolism, lipid and fatty acid biosynthesis and transport, muscle cellular type, and cellular components, which were related to raw meat quality. Different rearing systems also resulted in differences in glycolipid metabolism, lipid metabolism, and altered levels of intramuscular fat content and other flavor precursors. Pathways such as glycerolipid metabolism, adipocytokine signaling, and metabonomic pathways such as linoleic acid, glycerophospholipid, arginine, proline, and β-alanine metabolism may be responsible for the meat quality and flavor change.

Background: Chicken skin colour is an economically important trait influenced by consumer preferences across different markets. Previous studies established that white skin is dominant over yellow skin, with the β, β-carotene-9',10'-dioxygenase ( BCO2 ) identified as the candidate gene. However, the precise causal mutation within this gene region has remained unidentified for over a decade, limiting the development of reliable molecular markers for breeding programs. Results: Through genome-wide association analysis of 381 chickens, we confirmed that the BCO2 gene region on chromosome 24 was the major locus associated with skin colour. Transcriptome analysis revealed approximately 590-fold higher BCO2 expression in white-skinned than yellow-skinned chickens. By integrating whole-genome sequencing data from 63 individuals with high-quality genome assemblies, we identified a 24-bp insertion that showed near-complete co-segregation with the yellow skin phenotype in a backcross family of 180 individuals. Electrophoretic mobility shift assays revealed an insertion-dependent DNA–protein interaction, and DNA pull-down coupled with liquid chromatography-tandem mass spectrometry (LC–MS/MS) prioritised lymphoid enhancer-binding factor 1 (LEF1) as a leading candidate interactor. Chromatin profiling revealed elevated trimethylation of histone H3 at lysine 27 (H3K27me3) and reduced chromatin accessibility at the gene locus in yellow-skinned chickens. Functional experiments revealed that knockdown of LEF1 or inhibition of enhancer of zeste homologue 2 (EZH2) significantly increased BCO2 expression, supporting a model in which the insertion is associated with LEF1/EZH2-sensitive, polycomb repressive complex 2 (PRC2)-linked repression and transcriptional silencing. Conclusion: The 24-bp insertion in the BCO2 regulatory region is a candidate causal variant for yellow skin in chickens, refining the genetic model of chicken skin colour variation and supporting a LEF1-PRC2-associated regulatory mechanism potentially involved in avian carotenoid metabolism. This finding enables the development of a reliable PCR-based diagnostic marker for skin colour, facilitating marker-assisted selection in poultry breeding and providing new insights into the genetic regulation of avian pigmentation.