Foods最新文献

Pseudomonas aeruginosa elastase LasB accelerates refrigerated food spoilage through proteolytic degradation of muscle and milk proteins. While Marrubium vulgare essential oil terpenes exhibit antimicrobial activity, their weak potency and nonspecificity limit direct food preservation applications. This computational study aimed to rationally redesign terpene scaffolds into predicted selective LasB inhibitors. A virtual library of 635 terpene-peptide-phosphinic acid hybrids (expanded to 3940 conformers) was evaluated using consensus molecular docking (Glide/Flare) against LasB (PDB: 3DBK) and three human off-target proteases. Top candidates underwent duplicate 150 ns molecular dynamics simulations with MM/GBSA binding free-energy calculations. Computational screening identified thymol-Leu-Trp-phosphinic acid as the lead candidate with predicted binding affinity of -12.12 kcal/mol, comparable to reference inhibitor phosphoramidon (-11.87 kcal/mol), and predicted selectivity index of +0.12 kcal/mol representing a 2.3 kcal/mol advantage over human proteases. Molecular dynamics simulations indicated exceptional stability (98.7% stable frames, 0.12 Å inter-replica RMSD) with consistent zinc coordination. Structure-activity analysis revealed phosphinic zinc-binding groups (+1.57 kcal/mol), Leu-Trp linkers (+2.47 kcal/mol), and phenolic scaffolds (+1.35 kcal/mol) as predicted optimal structural features. This in silico study provides a computational framework and prioritized candidate set for developing natural product-derived food preservatives. All findings represent computational predictions requiring experimental validation through enzymatic assays, food model studies, and toxicological evaluation.

Covalent modification of polyphenols effectively enhances functional properties of proteins. This study conjugated potato protein isolate (PPI) with gallic acid (GA) via an alkaline method to investigate structural and functional alterations. Successful conjugation was confirmed by a significant decrease in free amino and sulfhydryl groups, coupled with a marked increase in total phenolic content. Multispectroscopic analyses indicated a loosening of the secondary structure and notable changes in the tertiary conformation. Molecular dynamics (MD) simulations corroborated these findings, revealing that GA conjugation induced conformational expansion, improved structural stability, and enhanced surface hydrophilicity. These structural modifications led to substantial functional improvements in the PPI-GA conjugates, including enhanced dispersion stability, improved emulsifying performance, strengthened antioxidant activity, and increased thermal stability. This research may provide effective strategy and technical support for the improvement of functional properties of PPI and expand its application in the food industry.

Background: Oxidative degradation during deep frying negatively affects the nutritional quality and stability of edible oils. Rapid, non-destructive methods to monitor oxidation, particularly in antioxidant-enriched oils, are therefore of growing interest.

Materials and methods: This study investigates the potential of near-infrared (NIR) spectroscopy combined with chemometric modeling-specifically the Stepwise Decorrelation of Variables (SELECT) algorithm and Ordinary Least Squares (OLS) regression-to quantitatively assess oxidation dynamics in edible oils enriched with hydroxytyrosol extract from olive fruit during deep frying. Extra virgin olive oil, virgin olive oil, refined olive oil, refined sunflower oil, and high-oleic sunflower oil were evaluated under controlled thermal degradation conditions.

Results: Variable selection identified key NIR spectral regions related to acidity, conjugated dienes (K₂₃₂), secondary oxidation indices (K₂₇₀ and ΔK), peroxide value (PV), anisidine value (AnV), and the total oxidation (TOTOX) index. From 700 measured wavelengths, a limited number were sufficient for robust prediction (16-30 wavelengths depending on the parameter), with critical sensitivity observed around 1792 nm and 1392 nm. The optimized NIR-SELECT-OLS models showed strong predictive performance across oil types (R² > 0.90; explained variance > 85%).

Conclusions: The results demonstrate that hydroxytyrosol enrichment enhances the oxidative and nutritional stability of edible oils during deep frying. Moreover, the integration of NIR spectroscopy with chemometric modeling provides an effective, non-destructive tool for real-time monitoring of oil oxidation, supporting sustainable quality control, process optimization, and antioxidant fortification in functional edible oils.

Artisanal colonial cheese (ACC) produced from raw milk is a rich reservoir of autochthonous lactic acid bacteria (LAB), but strain-level evidence supporting safe downstream application and technological stability remains limited. In this study, 10 LAB isolates from ACC were screened for phenotypic safety, antimicrobial susceptibility, and probiotic-related traits, and their viability was further assessed after inulin-based spray-drying microencapsulation under different storage temperatures. All isolates showed no hemolytic or mucinolytic activity and did not produce gelatinase, supporting an initial safety profile, and all strains were sensitive to at least two antimicrobial classes. Strain prioritization identified Lacticaseibacillus casei LAB06, LAB09, and LAB10 and Lactiplantibacillus plantarum LAB03 as the most robust candidates for downstream development because they maintained stable cell counts throughout simulated gastrointestinal digestion. Inulin spray-drying yielded structurally stable microcapsules and supported refrigerated storage, with substantially lower viability losses at 4 °C than at 25 °C; notably, L. plantarum LAB01 and LAB02 showed the best refrigerated shelf-life, remaining above 6.0 log CFU/g after 45 days. Together, these results position ACC as a source of promising LAB candidates and highlight cold-chain-compatible microencapsulation as a strategy to support safe functional food development with potential public health benefits.

L-theanine is a bioactive non-protein amino acid predominantly derived from tea plants (Camellia sinensis), widely recognized for its potential benefits in mood regulation and psychological health. Despite its promising neuropsychological profile, the specific molecular targets and mechanisms underlying its antidepressant activity remain incompletely understood. In the present study, an integrated network pharmacology strategy, combined with molecular docking and molecular dynamics (MD) simulations, was employed to systematically elucidate the potential antidepressant mechanisms of L-theanine. By intersecting predicted drug targets with depression-related genes, 40 potential targets were identified. Protein-protein interaction (PPI) network analysis subsequently pinpointed five hub targets: PRKACA, GRIA2, GRIN1, GRIA1, and HTR1A. Functional enrichment analyses (KEGG and GO) indicated that these targets are primarily implicated in critical pathological processes of depression, including neurotransmitter regulation, glutamatergic synaptic transmission, stress response signaling, and neurotrophin-related pathways. Molecular docking revealed favorable binding affinities between L-theanine and the key targets. Furthermore, MD simulations and binding free energy calculations corroborated the structural stability and thermodynamic favorability of these protein-ligand complexes. Overall, this study provides hypothesis-generating insights into the antidepressant mechanisms of L-theanine from a multi-target perspective, offering a theoretical foundation to guide future experimental validation in depression research.

Marine bioactive substances exhibit structural diversity and function-specific properties, attracting considerable interest in their potential applications in targeted nutritional delivery to the gut and microbiota regulation. These bioactive components, sourced from seaweed, marine crustaceans, and microorganisms, including polysaccharides, polyphenols, and lipids, demonstrate exceptional biocompatibility and specific recognition capabilities. They serve as an optimal carrier matrix and functional core for developing an efficient, precision-targeted intestinal nutrition delivery system. Research findings demonstrate that optimization via innovative delivery technologies, including nanoencapsulation and polymer microsphere encapsulation, enables marine bioactive substances to navigate various physiological barriers in the gastrointestinal tract effectively. This facilitates targeted, sustained release of nutritional components and enhances bioavailability. Simultaneously, these substances may relieve dysbiosis by modulating the composition of the gut microbiota and the quantity and activity of specific metabolic products, thereby reinforcing intestinal barrier integrity. This narrative review systematically examines the sources and functional attributes of marine bioactive compounds, emphasizing their application strategies in developing targeted delivery systems for the gut and their regulatory effects on gut microbiota. It concludes by delineating future research directions in this field, particularly in optimizing carrier functionalities and clarifying action mechanisms.

Walnut peptide Lys-Gly-His-Leu-Phe-Pro-Asn (KG-7) is a food-derived bioactive peptide with a high antioxidant capacity. We systematically evaluated the ameliorative effects of KG-7 on scopolamine-induced memory deficits in mice and its intestinal absorption mechanisms through integrating motion behavior analysis, molecular biochemistry research, and fluorescence imaging technology. Morris water maze tests revealed that KG-7 significantly improved the behavioral performance of these mice. Further mechanistic investigations demonstrated that KG-7 restored cholinergic function by reducing acetylcholinesterase activity and increasing acetylcholine levels. Hematoxylin-eosin staining and hippocampal immunohistochemistry confirmed that KG-7 alleviated neuronal damage by downregulating Hes1 overexpression, clarifying its behavioral improvement mechanism. In vitro fluorescence imaging showed that KG-7 reached peak accumulation in brain tissue 8 h post-administration, confirming its brain delivery. To elucidate the absorption mechanism, immunohistochemistry and immunofluorescence revealed that KG-7 markedly reduced the expression of efflux transporter P-gp in the small intestine, thereby diminishing efflux activity, while weakened tight junction (Occludin, ZO-1) fluorescence indicated activation of the paracellular pathway. Western blot analysis confirmed that KG-7 enhanced paracellular absorption efficiency and reduced intestinal efflux by downregulating ZO-1, Occludin, and efflux transporters (P-gp, BCRP, and LRP1) alongside upregulating Claudin-2 expression. These findings provide a foundation for exploring walnut peptides that enhance memory and optimize absorption.

This narrative historical review assesses the relationship between personality traits and the preference for spicy foods. While genetic, cultural, and personality factors have all been shown to influence taste preferences, the evidence that has been published to date suggests that personality plays a greater role in the liking and consumption of spicy food than for those basic tastes linked to the essential elements of a healthy diet. Archaeological and historical data illustrate the global dissemination and cultural integration of Capsicum into the human diet. Meanwhile, physiological and psychophysical research highlight that the pungent quality of capsaicin, together with the gustatory and olfactory cues associated with the flavour of chilli, affects hedonic evaluation, with repeated exposure often increasing acceptance through a process of desensitisation. Developmental factors, such as prenatal taste/flavour transmission and benign risk learning during childhood, underpin adult preferences. Cross-cultural studies reveal that the tolerance for pungency varies by country/culture and is also markedly shaped by personality traits. Recent social media trends have also increased some people's exposure to very spicy foods, linked to their sensation-seeking tendencies. As such, those theories that focus solely on biological sensitivity and cultural exposure likely fail to capture personality-driven factors like sensation seeking and reward sensitivity that drive the liking for spicy foods.

Half-smooth tongue sole has high nutritional value due to its delicious meat and high protein content. However, its high protein content makes it highly susceptible to spoilage caused by microbial action. This study utilized plasma-activated water to pretreat half-smooth tongue sole, which was then subjected to various packaging methods: CK (air packaging), VP (vacuum packaging), MAP1 (75% CO₂/5% O₂/20% N₂), MAP2 (20% CO₂/5% O₂/75% N₂), and MAP3 (75% CO₂/10% O₂/15% N₂). The packaged samples were stored at -1 °C. Preservation efficacy was assessed by monitoring changes in microbial counts and physicochemical quality indicators throughout storage. The findings revealed a progressive increase in microbial counts, a deterioration in fish quality, and a darkening of color over extended storage periods. During superchilling storage, the increase in total volatile basic nitrogen (TVB-N) and K value was markedly reduced in the MAP1 group. Regarding protein stability, the MAP1 group exhibited a slower rise in carbonyl content as well as a slower reduction in total sulfhydryl content, further confirming its superior preservation effect. Moreover, this group demonstrated excellence in maintaining the secondary and tertiary structures of myofibrillar proteins, thereby minimizing the structural damage of fish during superchilling storage. In summary, based on observed microbial and protein changes, MAP1 (75% CO₂/5% O₂/20% N₂) was the most effective in preserving quality and extending shelf life.