This study explores the role of the nucleic acid deglycase DJ-1 protein in regulating mitochondrial apoptosis during post-slaughter storage of Qinchuan beef via the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. The study evaluates the expression of key proteins in the PI3K/Akt pathway, apoptotic proteins, DJ-1 protein, as well as markers of oxidative stress, mitochondrial damage, and apoptosis. Our results indicate that prolonged post-slaughter storage suppressed the DJ-1-mediated PI3K/Akt signaling pathway, which regulates the expression of downstream proteins. This cascade leads to mitochondrial damage and ultimately induces apoptosis. In contrast, treatment with the DJ-1 stabilizer compound-23 modulates mitochondrial function through the PI3K/Akt pathway. This intervention reduces reactive oxygen species levels, inhibits the opening of the mitochondrial permeability transition pore, attenuates the loss of mitochondrial membrane potential, lowers caspase-3 activity, and decreases the B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 ratio, thereby effectively suppressing mitochondrial apoptosis. These findings establish a solid foundation for understanding the role of the DJ-1 protein and PI3K/Akt signaling pathway in post-slaughter myocytes. (c) 2027 The authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Collagen from livestock by-products has become an important strategic resource for the development of bioactive peptides due to its sustainable sourcing and unique amino acid composition. As a high-value product of collagen transformation, collagen peptides demonstrate exceptional versatile potential through their distinctive sequence architecture, dynamic self-assembly properties, and abundant modifiable sites. The characteristics of collagen peptides not only endow them with multiple bioactivities, including antioxidant, anti-inflammatory, and tissue regeneration effects, but also drive industrial breakthroughs in multiple fields: in food industry, they are used as intelligent preservation materials and functional enhancers, improving product quality and nutritional value; in biomedicine, they are employed to construct targeted drug delivery systems and biomimetic tissue scaffolds, accelerating the translation of precision medicine; in materials science, they are utilized to develop environmentally responsive smart materials, expanding applications in flexible devices and green packaging. This review provides a comprehensive overview of the green preparation technologies, molecular structural characteristics, and multi-target physiological activity mechanisms of collagen peptides, and discusses their application progress in food, medicine, materials and other fields. By synthesizing current knowledge, this work offers theoretical support for the resource utilization of livestock by-product collagen and highlights innovative pathways for the deep development of collagen peptides in chronic disease intervention, regenerative medicine, and smart materials.

This study investigated the effects of three heat treatment methods (steaming, roasting, and stir-frying) on changes in protein conformation, flavor profiles, and lipid components of Tan lamb meat. The results showed that stir-frying promoted the oxidation of lipids and proteins most significantly, followed by roasting, while steaming resulted in the lowest oxidation level. This phenomenon was attributed to differences in heating temperatures, heat transfer efficiencies, oxygen exposure, and the degree of heat-induced dehydration. A total of 217 volatile flavor compounds (VFCs) were identified using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC & times; GC-TOF-MS). Through multivariate statistical analysis combined with odor activity value (OAV) analysis, 1-octen-3-ol, (E,E)-2,4-decadienal, octanal, and (Z)-4-decenal were determined as key VFCs. Pearson correlation analysis revealed significant correlations between these key VFCs and changes in protein conformation. Furthermore, lipidomic analysis of Tan lamb samples subjected to different heat treatment methods revealed that the differential lipids were mainly glycerophospholipids (GPs) and glycerolipids (GLs). Among these, triglyceride (TG) 18:1_18:1_18:1 and lysophosphatidylcholine (LPC) 19:1 were identified as potential biomarkers for monitoring the extent of thermal processing and predicting lamb flavor formation. This study contributes to the in-depth elucidation of the underlying mechanisms of flavor variation in Tan lamb under diverse heat treatment methods.

Xanthine (XA) and hypoxanthine (HA) are key biochemical markers of meat freshness, yet rapid, wide-range, and enzyme-free quantification in complex meat matrices remains challenging. Here we report a density functional theory (DFT)-guided Cu–MoS2/g-C3N4 heterostructure electrochemical sensor for broad-range non-enzymatic detection of XA and HA. The heterojunction prepared via a hydrothermal and ultrasonic strategy provides an efficient charge-transport pathway and enriched catalytic interfaces. DFT calculations reveal pronounced interfacial charge redistribution and strong adsorption of XA and HA on the Cu–MoS2/g-C3N4 surface, with adsorption energies of − 0.98 eV for XA and − 2.16 eV for HA, explaining the boosted electrooxidation response. The sensor achieves low detection limits of 0.15 μM for XA and 0.28 μM for HA and wide linear ranges from 0.913 to 1643.5 μM and from 0.918 to 1653.1 μM, respectively, and enables simultaneous quantification from 0.5 to 400 μM with excellent linearity. Good stability, reproducibility, and anti-interference capability are obtained. In real meat samples, recoveries from 90.7

Postmortem aging is a critical step in sheep meat processing from slaughter to consumption. This study aimed to investigate the dynamic changes in flavor related compounds in the Longissimus thoracis (LT) muscle of Tan sheep during a 144 hour postmortem aging period, as well as the upstream mechanisms underlying flavor development. The results showed that as postmortem aging progressed, lipid degradation gradually intensified, the relative concentration of flavor compounds changed significantly (P < 0.05), such as esters, aldehydes, and alcohols. Non-targeted metabolomics revealed that flavor-related metabolic pathways, including protein, lipid, and nucleotide metabolism, were progressively activated during postmortem aging. Notably, metabolic activity within the LT muscle of Tan sheep transitioned from an intense phase to a steady state from 48 h to 96 h. Correlation analysis revealed that lipid-related metabolites were significantly correlated with certain volatile organic compounds that contributed markedly to discriminating postmortem aging time (P < 0.05). We identified seven lipid-metabolism-related differential metabolites as potential markers for flavor maturation: butyrylcarnitine, methylmalonylcarnitine, Lpe(18:2), Pe(18:2/0:0), O-succinylcarnitine, Pc(O-16:0), and (R)-3-hydroxybutyrylcarnitine. This finding strongly supports the central role of oxidative lipid degradation in flavor development, corroborating the pivotal role of oxidative degradation of lipids in flavor development.

In this study, flavonoid nanoemulsions (FN) were prepared by extracting flavonoids from daylilies, and their particle size, zeta potential, apparent viscosity, and antioxidant activity were characterized. Subsequently, double-layer composite films were fabricated via a layer-by-layer assembly method using carrageenan (CG) and FN as the inner layer, and chitosan (CS), gelatin (GEL), and titanium dioxide nanoparticles (TiO2NPs) as the outer layer. The results showed that the nanoemulsions containing a flavonoid concentration of 0.8 mg/mL exhibited the smallest particle size (76.84 nm), the highest absolute Zeta potential (20.07 mV), optimal stability, and excellent antioxidant activity. Further, the morphological and storage stability analyses of the 0.8 mg/mL flavonoid nanoemulsion revealed its excellent dispersion and storage stability. In bilayer composite films, the incorporation of FN increased the moisture content to 38.6% and film thickness to 0.094 mm (P < 0.05). The incorporation of TiO2NPs reduced the moisture content of the composite film from 38.6% to 30.8%, significantly increased its water contact angle and L⁎ value, and decreased its transmittance (P < 0.05). Furthermore, scanning electron microscopy revealed that the addition of FN and TiO2NPs reduced the smoothness of the film surface. Moreover, the incorporation of FN and TiO2NPs effectively enhanced the antioxidant and antibacterial properties of the film. Furthermore, the composite film containing FN and TiO2NPs significantly inhibited the lipid oxidation of mutton and maintained the total volatile basic nitrogen value within a safe range, indicating that the composite film has potential in the field of food packaging.

In this work, polyphenol nanoparticles-loaded oxidized hydroxypropyl starch/carrageenan (OC/SPH NPs) films were prepared and applied to the preservation of fresh-chilled beef. The mechanism by which OC/SPH NPs films inhibit quality deterioration in fresh-chilled beef was investigated through analyses of endogenous enzyme activity, protein oxidative degradation, secondary structure, MFI values and TCA-soluble peptides. The results indicated that the active components in the composite film successfully migrated into the beef, while the remaining antioxidant capacity of the film decreased. Endogenous enzymes in the beef gradually release into the exudate over extended storage periods. By day 18, the activities of tissue protease B, L, D, and calpain in the exudate reached 25.42 U/g, 33.97 U/g, 0.73 U/g, and 14.29 U/g, respectively. This indicates that the OC/SPH NPs film significantly inhibited the activity of endogenous enzymes in beef, delayed changes in protein oxidation indicators such as sulfydryl, carbonyl content, Ca2+-ATPase activity, and surface hydrophobicity; simultaneously, it slowed the transition of α-helices to random coils, maintaining the structural stability of myofibrillar protein (MP). Compared with the control film, the MFI value and TCA-soluble peptides of beef treated with the composite film decreased by 32.1% and 27.61%, respectively. After incubation with exudate for 12 h, the degradation extent of MPs was reduced, indicating that the OC/SPH NPs film absorbed exudate and delayed the deterioration of beef texture. The results elucidate that the OC/SPH NPs film protects beef texture stability by reducing endogenous enzyme activation, protein oxidation, and degradation.

This study examined the role of the lysosomal-mitochondrial apoptosis pathway in the tenderization of lamb meat during postmortem aging. Upon injection into lamb meat, deferoxamine (DFO) reduced oxidative damage to lysosomes, inhibited the permeability of the mitochondrial membrane, reduced apoptosis, and altered the tenderness of meat. The decline in lysosomal membrane permeabilization (LMP) led to an increase in cathepsin D levels. BH3 interacting domain death agonist (Bid) and BCL-2-associated X protein (Bax) levels in the early post-slaughter period further impaired mitochondrial membrane stability and induced apoptosis. Reduction level of Cytochrome c (Cyt-c), the expression of cysteinyl aspartate specific proteinase (caspase-9, caspase-3), and the increase in apoptosis were higher in the control group than in the DFO group (P < 0.05). The increase in the myofibril fragmentation index(MFI) and the decrease in pH value and shear stress (P < 0.05) demonstrated that the tenderness of lamb meat was improved after treatment. Correlation analysis showed that lysosomal-mediated mitochondrial apoptosis had a positive effect on the tenderness of lamb meat during postmortem aging.

This study systematically investigated the quality changes of buckwheat hele noodles (BHN) during frozen storage at -18 °C for 80 days. Pronounced lipid-protein co-oxidation was observed, characterized by a 71.9% rise in malondialdehyde (MDA) and a 133.2% rise in carbonyl content. Sulfhydryl content showed a continuous decline, while the levels of key unsaturated fatty acids progressively decreased. The activities of lipoxygenase (LOX) and catalase (CAT) gradually diminished, thereby inhibiting enzymatic oxidation but promoting non-enzymatic oxidation. Microscopic analysis revealed a disrupted gluten network with enlarged pores, and the proportion of β-sheet structures in protein secondary structures increased significantly, suggesting enhanced protein aggregation and cross-linking. Flavor analysis indicated that the levels of aldehydes and ketones peaked at 40 days, with 2-nonenal and 1-octen-3-ol identified as the key off-flavor compounds. Correlation analysis confirmed that protein and lipid oxidation were the primary driver of quality deterioration in BHN during frozen storage.

This study investigated hypoxia-inducible factor (HIF)-1 alpha-mediated proteomic changes in post-slaughter Tan sheep skeletal muscle and identified energy metabolism biomarkers using the competitive adaptive reweighted sampling (CARS) algorithm. HIF-1 alpha inhibition during early storage attenuated pH decline and significantly increased total colour change (Delta E) (P<0.05) while reducing myofibril fragmentation compared with controls. Proteomic profiling identified 257 differentially expressed proteins enriched in adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), glycolysis, and HIF-1 signalling pathways. CARS analysis highlighted lactate dehydrogenase A (LDHA), phosphoglycerate kinase 1 (PGK1; glycolytic enzyme), heat shock protein beta-6 (HSPB6), and heat shock protein 90 kDa beta 1 (HSP90B1) as key energy metabolism biomarkers. The results suggested that HIF-1 stabilised ATP production under hypoxia conditions by suppressing glycogen synthesis, enhancing glycolysis, modulating HSP activity to preserve cellular homeostasis, and influencing cytoskeletal proteins, thereby affecting meat quality. These results provide novel insights into post-mortem muscle energy metabolism regulation and potential targets for meat quality optimisation.

This study assessed the suitability of oxidized hydroxypropyl starch/carrageenan films conjugated with polyphenol nanoparticles (OC/SPH NPs) for preserving chilled beef. Results indicated that the composite film is particularly suitable for acidic foods such as beef. The OC/SPH NPs film significantly delayed increases in pH, b* value, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and total viable count (TVC), while retarding the decline in L* and a* values and sensory scores. Meanwhile, the OC/SPH NPs altered the bacterial diversity of the chilled beef and effectively inhibited the spoilage bacteria's growth and spoilage odor in beef. In the PE group, Myroides, Acinetobacter and Serratia showed positive correlations with TBARS and TVB-N, whereas in the composite film group, these genera were negatively correlated with key flavor compounds. The film structure remained intact after storage, demonstrating its stability and suitability for preserving chilled beef, extending its shelf life to 15 days.

This study investigated the influence of Goji bud tea (GBT) as a functional ingredient on the nutritional quality and flavor of chicken soup. The results showed that adding GBT significantly increased the soluble solids, water-soluble protein, amino acid nitrogen, total phenolic, and total flavonoid contents of chicken soup, thereby enhancing its nutritional value and antioxidant activity. In addition, the levels of free amino acids and 5'-nucleotides also increased following GBT addition. Through gas chromatography-mass spectrometry analysis, a total of 48 aroma components were detected. Further, through orthogonal partial least squares discriminant analysis and random forest models, eucalyptol, linalool, 1-nonanol, nonanal, benzaldehyde, and octanal were identified as potential key aroma substances in GBT-enriched chicken soup. This study systematically clarified the potential of GBT in enhancing the nutritional value and flavor of chicken soup, providing theoretical and evidence-based support for the development of functional stews.

In order to investigate the effect of caspase-3 on the water retention and tenderness of Tan sheep meat during postmortem aging,the right hind leg meat of Tan sheep was injected with Ac-DEVD-CHO,a caspase-3 inhibitor,or 0.8%NaCl(control group),and aged at 4℃.After 0,6,12,24,48,96 and 192 h,the activity of caspase-3 and caspase-9,water distribution,degradation of myofibrillar proteins,microstructure and water retention and tenderness indicators were determined.The results showed that with increasing postmortem aging time,the activity of caspase-3 and caspase-9 in the DEVD group was inhibited,and the myofibril fragmentation index(MFI)showed a significantly lower upward trend than the control group(P<0.05).The pH initially decreased and then increases,and the ultimate pH was lower while the pH at 192 h was higher in the DEVD group than in the control group(P<0.05).At 24-192 h postmortem,the cooking loss,centrifugal loss,T23 transverse relaxation time and shear force of the DEVD group were distinctly higher than those of the control group.Moreover,during the early postmortem period,the microstructural integrity of muscle in the DEVD group was better than that of the control group.In summary,during the early post-slaughter period(0-24 h),DEVD preserved the integrity of myofibrils and slowed down the process of apoptosis by inhibiting the activity of caspase-3,which resulted in the deterioration of the water retention and tenderness of Tan sheep meat.In the late post-slaughter period(48-192 h),the rise in pH weakened the effect of DEVD,and the consequent rapid activation of caspase-3 accelerated the degradation of myofibrils,thereby improving meat tenderness.Furthermore,the rise in MFI aggravated the collapse of muscle structure,resulting in poor water retention of Tan sheep meat.Overall,the DEVD treatment had a stage-specific effect on the quality of Tan sheep meat during postmortem aging.

This study systematically evaluated the capability of near-infrared hyperspectral imaging (HSI) for rapid and non-destructive detection of wheat grain quality across 14 varieties from multiple ecological zones in Ningxia. By integrating machine learning approaches, predictions were made on the protein content of these wheat varieties. Results demonstrated that the Convolutional Neural Network (CNN) model achieved the highest coefficient of determination (R2) on both training and test datasets, indicating superior fitting performance and predictive accuracy. Among the feature wavelength extraction methods, the iterative Variable Importance in Projection on Latent Structures (iVISSA) technique stood out. After applying this method, the CNN model attained a test set R2 of 0.9058 and a Root Mean Square Error (RMSE) of 0.4283, significantly enhancing model performance. These findings suggest that iVISSA effectively identifies feature wavelengths highly correlated with protein content, thereby improving the model's precision and generalization capability. In conclusion, near-infrared hyperspectral imaging combined with machine learning models offers a powerful tool for accurately predicting wheat grain protein content, providing valuable technical support for wheat quality assessment in Ningxia.

Starch, the predominant component of maize, is integral to numerous industrial processes, including ethanol production and adhesive manufacturing. Accurate and efficient quantification of starch content in maize is essential for optimizing industrial productivity and reducing operational costs of maize production. This study aimed to develop a robust predictive model using hyperspectral imaging combined with advanced generative algorithms to enable the rapid, non-destructive determination of maize starch content. A total of 80 maize samples were collected from various locations in Ningxia, China, to establish a quantitative relationship between hyperspectral responses and starch content. The dataset was augmented using a Vector Quantized Variational Autoencoder (VQ-VAE), which discretizes continuous spectral features into a structured codebook space, significantly enhancing data diversity and model generalization capabilities. The experimental results demonstrated that the dataset augmented with VQ-VAE significantly improved the accuracy and stability of the regression models. Compared to conventional autoencoders (AE) and Generative Adversarial Networks (GAN), VQ-VAE-generated data preserved the critical characteristics of the original dataset while expanding its distribution range, thus enhancing the robustness of the model. A Convolutional Neural Network (CNN) model trained on this enriched dataset achieved an R2 value of 0.7510 and a Root Mean Square Error (RMSE) of 0.4413 on the test set, underscoring its superior predictive accuracy and generalization potential. This study provides a novel methodological framework for the rapid, non-destructive, industrial-scale determination of maize starch content.

In order to investigate the occurrence of cellular autophagy and its effect on the meat color of Qinchuan cattle during postmortem aging,the changes in the meat color,relative myoglobin content,metmyoglobin reductase activity(MRA),beclin1,microtubule-associated protein light chain 3-II(LC3-II),autophagy-related protein 7(ATG7),sequestosome 1(p62),caspase 8,mitochondrial membrane potential(MMP),reactive oxygen species(ROS)levels of the longissimus dorsi muscle of Qinchuan cattle were determined at different time points during postmortem aging at 4℃.It was found that as the aging time was prolonged,L* and a* values as well as beclin1,LC3-II and ATG7 protein expressions initially increased and subsequently decreased,caspase 8,p62 and ROS showed an opposite trend;the relative contents of deoxymyoglobin(DeoMb)and oxymyoglobin(OxyMb),MMP and MRA decreased,whereas b* value and the relative content of metmyoglobin(MetMb)increased.Moreover,the key proteins related to cellular autophagy were expressed to different degrees during the postmortem process,and muscle cells exhibited autophagy,the strongest autophagic activity being observed at 96 h.Correlation analyses showed a highly significant correlation among the key proteins related to cellular autophagy(P<0.01),indicating that these proteins were closely related to each other in cellular activity.There were significant correlations between meat color parameters and cellular autophagy-related proteins and mitochondrial function at 0-96 h during the postmortem process(P<0.05).The above results showed that the changes in mitochondrial function and autophagy in myoblasts during the early postmortem period affect meat color,and beclin1,LC3-II,ATG7,p62,and caspase 8 can be used as biomarkers to predict the changes of meat color during the postmortem process.

This study investigated the dynamic synergy of hypoxia-inducible factor-1 (HIF-1) in energy metabolism after the slaughter of Tan sheep and its impact on meat color development. The longest dorsal muscle was incubated with the HIF-1 inhibitor YC-1 or 0.9% saline (the control) at 4 degrees C for 0, 1 and 2 days. Results from proteomics and enzyme activity assays showed that the activation of HIF-1 enhanced the activities of glycolytic enzymes, particularly phosphofructokinase and phosphoglycerate kinase, while inhibiting the electron transport chain. Proteomic analysis revealed significant changes in the expression of these proteins, indicating that HIF-1 regulates energy supply and demand allocation through signaling pathways, such as AMPK and AK. This led to changes in ATP levels, increased AMP and ADP concentrations, and an elevated energy charge in the inhibition group, highlighting the critical role of HIF-1 in post-mortem muscle energy metabolism and meat color stability.

This study explored the effects of grape seed proanthocyanidin (GSP) in synergy with sesbania gum (SG) on the antioxidant capacity, processability, moisture distribution, microstructure, and sensory properties of lamb sausages, to evaluate their synergistic advantages in improving sausage quality and SG's potential as a fat substitute. Findings revealed that GSP enhanced radical scavenging abilities (P < 0.05), while reducing thiobarbituric acid reactive substances (TBARS) and carbonyl content (P < 0.05). However, 0.10 % GSP supplementation decreased the degree of network structure polymerization. Adding 5 % SG reduced the fat content and energy value (P < 0.05), and promoted transitions in protein secondary structures from α-helix to β-sheet. Dynamic rheological behavior, scanning electron microscopy, and confocal laser scanning microscopy results showed that SG incorporation increased the storage modulus (G') and formed a denser network structure. This structural modification further improved the texture properties (hardness, gumminess, and chewiness) and reduced the shrinkage rate (P < 0.05). Low-field nuclear magnetic resonance analysis demonstrated that SG facilitated the conversion of free water to immobilized water and reduced the cooking loss rate (P < 0.05). Sensory evaluation pointed out that incorporating 5 % SG as a fat substitute in lamb sausages increased the flavor, juiciness, texture, and acceptability scores. Overall, the synergistic application of 0.10 % GSP and 5 % SG exhibited multiple benefits, namely enhancing antioxidant capacity, reducing fat content, and simultaneously improving the processing properties. These findings indicate that SG serves as a promising fat substitute that enables increased loading capacity of polyphenols without deteriorating the sausage quality.

This study investigates the effects of Sesbania gum (SG) on the characteristics of oxidized myofibrillar protein (MP) gel and grape seed proanthocyanidin (GSP)-oxidized MP gel. The results demonstrated that GSP treatment promoted oxidized MP intermolecular protein aggregation and the formation of insoluble MP copolymers, reducing the densification of the gel network structure. SG supplementation significantly enhanced the rheological properties of oxidized and GSP-modified MP gel by facilitating the alpha-helix to beta-sheet transition, thereby improving water holding capacity and textural properties. Scanning electron microscopy (SEM) revealed that SG incorporation improved gel network densification and counteracted the degradation of gel properties caused by GSP-induced protein aggregation. These findings highlight the ability of SG to mitigate oxidative damage to the gel structure and inhibit GSP-protein interactions, thereby enhancing the properties of MP gel. This study provides a new strategy to improve the loading amount of phenolic antioxidants without deteriorating of the MP gel quality.