Search Results (5,660)

Oca (Oxalis tuberosa) skin is considered an agroindustrial waste byproduct, which currently holds no economic value. Nevertheless, this waste is a natural source of antioxidant compounds, which can be recovered through the use of sustainable technologies. Thus, this study aims to evaluate and compare the efficacy of 15% ethanol combined with two extraction techniques like solid–liquid extraction (SLE) and pressurized liquid extraction (PLE) for the recovery of antioxidant compounds from five oca skin cultivars. Regardless of the oca cultivar, the use of PLE was more efficient for obtaining extracts rich in polyphenol with high antioxidant capacity compared to the SLE process. Under PLE conditions, Pachatusan and Yawar cultivars presented the highest value of total polyphenols and antioxidant capacity. In comparison, the QuesWe and Pachatusan cultivars presented the lowest values. Polyphenol profile analysis showed that the PLE process effectively disrupted the cell wall matrix, resulting in a greater release of monomers (gallic acid, catechin, and epicatechin) and procyanidin B2 compared to the SLE process, while procyanidin A2 was more efficiently recovered under SLE, particularly in the Pachatusan cultivar. Principal component analysis (PCA) confirmed cultivar-dependent polyphenolic patterns, explaining 81.7% and 84.8% of total variance for SLE and PLE, respectively, with PLE generating more pronounced differentiation among cultivars driven by catechin, epicatechin, and gallic acid. The integration of PLE technology with the Oca skin framework facilitates the standardized production of extracts rich in antioxidants. Future research should concentrate on evaluating the stability of these specific dimers within food matrices, as well as their bioavailability in human clinical models. Full article

The pineal gland regulates circadian physiology through the periodic production of melatonin (MLT). In addition to its established role as a chronobiotic agent, MLT regulates redox homeostasis and mitochondrial physiology. Mitochondria and redox-active molecules, particularly reactive oxygen species (ROS), play essential roles in reproduction, including gamete physiology, fertilization, and early embryonic development. Although excessive oxidative stress (OS) impairs fertility, controlled ROS signaling is necessary for normal reproductive function. This comprehensive review synthesizes current evidence regarding MLT as a key intermediary linking circadian signaling with mitochondrial physiology and redox homeostasis. We discuss molecular pathways through which MLT regulates mitochondrial function, including activation of the Nrf2 signaling pathway, modulation of mitochondrial permeability transition, regulation of electron transport chain (ETC) efficiency, and apoptotic signaling. Furthermore, this study investigates MLT’s ability to scavenge free radicals and activate antioxidant defense mechanisms. Moreover, we review novel findings regarding the effects of MLT in experimental animals and humans, assisted reproductive technologies (ART) such as in vitro fertilization (IVF), and consider the translational significance of the hormone as an enhancer of fertility. We also highlight gaps in the literature, including methodological inconsistencies, supraphysiologic doses, and insufficient data from large human cohorts. Lastly, we discuss an integrative model whereby MLT may function as an important regulator of mitochondrial redox balance, with potential implications for reproductive physiology and reproductive outcomes, and propose new avenues for investigation. Full article

Oxidative stress has been recognized as a repeatedly validated pathophysiological factor in schizophrenia, but its mechanistic role and translational relevance remain incompletely defined. Prior work has advanced redox dysregulation, neuroinflammation, and NMDA receptor hypofunction as a putative central hub in schizophrenia. This narrative review proposes an evidence-weighted redox–mitochondria–immune framework that integrates peripheral biomarkers, magnetic resonance spectroscopy, postmortem findings, and preclinical mechanisms while explicitly distinguishing established observations from candidate pathways. Existing studies support increased oxidative damage and altered antioxidant buffering in schizophrenia, particularly involving the glutathione system. However, these abnormalities are neither uniform across disease stages nor equally represented across patient subgroups, and may be markedly prominent only in certain biological subgroups. Mechanistically, redox imbalance may interact with mitochondrial bioenergetic deficits and innate immune signaling; however, pathway-specific links such as cGAS-STING activation, nitrosative/peroxynitrite stress, and GPx4-ferroptosis should currently be treated as testable extensions rather than validated human mechanisms in schizophrenia. Importantly, the pathological consequences of oxidative stress are unlikely to be cell-type neutral. Parvalbumin-positive interneurons and oligodendrocyte lineage cells are more vulnerable because of their high metabolic load, limited antioxidant buffering capacity, and lipid/iron-related susceptibility, thereby providing a mechanistic bridge to excitation–inhibition imbalance, myelin abnormalities, and reduced circuit synchrony. Microglial redox–inflammatory signaling may further exacerbate these processes. On the basis of this framework, we argue that the key for future research is not to continue demonstrating the universality of oxidative stress, but to improve the translational efficiency. Biomarker-guided stratification, stage-sensitive study designs, and cell-type-informed therapeutic strategies may therefore provide a more productive path toward redox-targeted interventions in schizophrenia. Full article

The current research investigates the extraction efficiency of an emerging green technology, pressurized liquid extraction (PLE), compared to traditional stirring extraction (STE) in order to recover higher antioxidant capacity from three plant species of the Asteraceae family, namely Solidago virgaurea, Tussilago farfara, and Helichrysum stoechas. The optimal PLE conditions were achieved through a combined response surface methodology (RSM) approach. The resulting optimized PLE parameters (40% ethanol, 160 °C, 25 min, 1700 psi) were experimentally verified and directly contrasted with STE (40% ethanol, 80 °C, 60 min, 500 rpm). Despite having the same solvent polarity, the two methods showed significant variations in mass transfer kinetics and heat intensity. Across all species, PLE significantly boosted the ascorbic acid antioxidant capacity (p < 0.05), thereby showing enhanced recovery of compounds that contribute to the overall antioxidant capacity. STE generated noticeably increased total polyphenolic content and DPPH radical scavenging activity (p < 0.05), indicating that some phenolic subclasses might be susceptible to PLE at higher temperatures. Values for ferric-reducing antioxidant power were largely similar among approaches. Overall, PLE was shown to be highly effective in maximizing the total antioxidant capacity in shorter extraction times, while STE can better preserve specific polyphenolic fractions, as demonstrated through analysis of the optimal extracts by HPLC-DAD. The integration of experimental validation with chemometric modeling supports the reliability and practical applicability of the optimized PLE protocol. Full article

Four onion (Allium cepa L.) cultivars with different bulb colors (yellow Y14, red R12, red R10 and white W3) were characterized for phenotypic, metabolic, volatile, antioxidant, flavor and transcriptomic variations, to unravel key metabolites and molecular mechanisms responsible for quality differentiation. Y14 possessed the maximum bulb weight (535.34 g) and diameter (13.10 cm), along with the highest total phenolic content (3.10 mg·g⁻¹), showing superior yield and antioxidant properties. In R12, upregulated expression of carotenoid biosynthetic genes enhanced carotenoid accumulation, resulting in vivid bulb color. R10 had high total phenols (3.89 mg·g⁻¹) and the richest sweet-associated volatiles, featuring strong antioxidant activity and distinct sweetness. By contrast, W3 exhibited moderate flavor but inferior performance in yield, antioxidant capacity, pigment and volatile levels relative to the other three cultivars. Comprehensive assessment indicated that Y14 serves as an excellent processing material, R12 and R10 are ideal for fresh consumption and functional food development, and W3 is well-suited for raw salads. This study lays a theoretical foundation for onion quality improvement, targeted breeding and efficient utilization. Full article

In this study, we combine experimental and computational approaches to elucidate a density functional theory (DFT)-derived mechanism for superoxide scavenging by resveratrol, piceatannol, and oxyresveratrol. Using rotating ring–disk electrode (RRDE) hydrodynamic voltammetry, the superoxide radicals are generated in situ, allowing direct measurement of antioxidant activity. Data show that the catechol-containing piceatannol is approximately four times more active than resveratrol, while resveratrol and oxyresveratrol exhibit similar efficiencies, indicating that the additional 2′-OH group in oxyresveratrol has minimal impact. Vitamin C (ascorbic acid) facilitates scavenging by acting as a proton donor for resveratrol, piceatannol, and 4′-OH oxyresveratrol, but it is unable to deprotonate the 2′OH group of oxyresveratrol. The experimental results suggest a superoxide dismutase (SOD)-like mechanism, obtained from energetically feasible DFT calculations, in which these stilbenes convert two superoxide anions into H₂O₂ and O₂, helped by vitamin C. Mechanistically, the first superoxide is reduced by abstracting a hydroxyl-group hydrogen atom, while the second undergoes oxidation via π–π interaction with the aromatic system, releasing O₂. Notably, resveratrol can be regenerated through a catalytic cycle involving vitamin C. These data underscore the SOD-mimicking properties of dietary polyphenols and suggest a need to reevaluate resveratrol’s clinical utility regardless of its low bioavailability. Full article

Background: Effective strategies for delivering neuroprotective agents to the brain remain a major challenge due to the poor solubility, rapid metabolism, and low bioavailability of promising molecules, such as 7,8-dihydroxyflavone (7,8-DHF). This small-molecule TrkB receptor agonist exhibits significant antioxidant, neuroprotective properties, and additional effects on metabolic regulation, but its therapeutic potential is limited by unfavorable pharmacokinetic characteristics. Nanotechnology-based delivery systems are increasingly explored to improve drug stability, enhance bioavailability, and facilitate direct nose-to-brain transport following intranasal administration. In this study, lipid nanoparticles encapsulating 7,8-DHF were developed using a fish-oil-based lipid core enriched with ω-3 polyunsaturated fatty acids (DHA and EPA) and naturally derived excipients, including soybean lecithin and ε-polylysine. Methods: The formulation was optimized using a Design of Experiments (DoE) approach based on a 2³ full factorial design, evaluating drug concentration, lecithin concentration, and surfactant type (Pluronic^® F127 or Tween^® 80). The main formulation responses considered were particle size, polydispersity index (PDI), zeta potential, and encapsulation efficiency. Results: The optimized nanoparticles exhibited nanometric dimensions (<250 nm); spherical morphology, confirmed by TEM; low polydispersity (PDI < 0.3); and adequate encapsulation efficiency. Stability studies in simulated biological fluids indicated good physicochemical stability for up to 48 h, while interaction studies with mucin suggested a good interaction within the mucus environment. ROS scavenging capacity was confirmed through the DPPH chemical assay, and in vitro experiments on olfactory ensheathing cells, selected as a biologically relevant model for their anatomical localization along the olfactory pathway, showed reduced cytotoxicity of the encapsulated drug compared with the free form. Conclusions: Collectively, these results support the potential application of the developed nanoformulation in the intranasal delivery of 7,8-DHF. Full article

Introduction: Fish skin is the first line of defense against the aquatic environment, acting as a physical, chemical, and immunological barrier. In addition to preventing pathogen entry, the skin and its mucus contribute to osmoregulation, innate immunity, and redox balance. Skin lesions—caused by mechanical damage, parasites, environmental stress, or handling—disrupt this barrier, increasing susceptibility to infections, inflammation, and production losses. Thus, efficient skin regeneration is essential for fish welfare and performance. Nutrition plays a key role in this process by providing substrates for epithelial repair, immune function, and antioxidant defense. Among dietary factors, zinc (Zn) is particularly important due to its involvement in cell proliferation, enzymatic activity, and maintenance of skin integrity. Objective: Our objective is to assess the effectiveness of image-based analysis in quantifying the skin healing process in Atlantic salmon fed diets supplemented with zinc. Methodology: The trial comprised three dietary treatments: a control diet with 42 mg Zn per kg (D1), and two diets supplemented up to 120 mg/kg of zinc, derived from inorganic (D2) or organic (D3) forms. Pit-tagged fish with an initial body weight (78 ± 0.1 g) were fed the diets for 75 days. After 15 days of experimental feeding, a standardized wound lesion (2.5 mm diameter × 0.5 mm depth) was inflicted in deeply anesthetized fish, with a disposable biopsy punch, in the dorsal area. After wound infliction, the fish resumed their normal feeding regime for the rest of the trial days. The progression of skin wound healing was assessed using standardized digital image analysis. High-resolution photographs of individual wounds were collected 8, 16, 24 and 32 days post-wounding. All images were acquired under standardized conditions with the inclusion of ArUco identifiers to enable a subsequent computer-assisted comparison. Morphometric parameters (wound width, diameter, perimeter and area) were used to assess wound contraction and closure over time. In parallel, a semi-quantitative visual scoring system was applied to each wound image to capture qualitative aspects of healing that are not fully described by morphometric data alone. Results: Full data analysis is currently underway, but the first results show beneficial effects of dietary zinc supplementation on the skin regenerative process. Conclusions: The combined use of objective digital measurements and standardized visual scoring enabled a comprehensive evaluation of wound healing progress, bridging quantitative tissue remodeling with biologically relevant phenotypic outcomes. This image-based framework provides a sensitive and reproducible approach for assessing dietary interventions targeting skin regeneration and barrier restoration in Atlantic salmon. Full article

Bio-based and biodegradable polymer composites based on polylactic acid (PLA) and polybutylene succinate-co-adipate (PBSA) were developed for rigid food packaging applications. Agro-industrial residues consisting of ground leaves and branches derived from tangerine tree cultivation (pruning) were used as fillers at high loading (30 wt%) before (PRE) or after (POST) extraction of bioactive compounds. The influence of blend composition (PLA/PBSA 60/40 and 30/70), filler extraction, and the addition of antioxidants (0.5 wt%) on material properties was systematically investigated. Composites were processed via extrusion and injection molding and characterized through FTIR, SEM, tensile testing and thermal analysis. The results show that polymer blend morphology affects mechanical behavior, with co-continuous structures (60/40) exhibiting improved ductility compared to dispersed systems (30/70). The incorporation of lignocellulosic residues increased stiffness but reduced elongation at break. Extraction treatment significantly modified filler morphology and interfacial interactions, slightly improving dispersion and processability. The effect of the extracted bioactive compounds on the thermal stabilization of biocomposites was also investigated. Overall, the findings demonstrate the potential of combining biodegradable polymer blends with treated agricultural residues to produce sustainable rigid packaging materials while supporting a bio-circular approach. In fact, preliminary extraction of valuable compounds from tangerine pruning waste appears to be a convenient strategy for its efficient cascade valorization. Full article

In vitro maturation (IVM) is a critical step affecting the efficiency of bovine in vitro embryo production; however, oxidative stress during in vitro culture can impair oocyte quality and subsequent developmental competence. This study investigated the effects of cysteine supplementation on bovine oocyte IVM, redox homeostasis, mitochondrial status, and transcriptomic changes. Bovine cumulus-oocyte complexes were cultured in IVM medium supplemented with 0, 25, 50, 75, 100, or 125 μM cysteine, and 75 μM was identified as the optimal concentration. Compared with the control group, 75 μM cysteine increased the first polar body extrusion rate from approximately 78% to 81% and improved the fertilization/cleavage rate from approximately 74% to 82%. It also significantly increased the proportions of 2-cell, 4-cell, and 8-cell embryos, whereas morula and blastocyst rates were not significantly affected. At the cellular level, 75 μM cysteine significantly reduced ROS levels and increased GSH content, as indicated by changes in relative fluorescence intensity. JC-1 staining showed that the JC-1 monomer signal decreased from approximately 16.0 to 13.5, whereas the JC-1 aggregate signal increased from approximately 13.2 to 14.8, indicating improved mitochondrial membrane potential status. In addition, lipid droplet fluorescence intensity increased from approximately 11.8 to 13.4, mitochondrial fluorescence intensity increased from approximately 6.0 to 7.0, and cytoskeletal fluorescence intensity showed no significant difference between groups. Smart-seq2 transcriptomic analysis identified 1935 differentially expressed genes, including 1778 upregulated and 157 downregulated genes, which were mainly enriched in translation, ribosomal structural components, RNA binding, oxidative phosphorylation, and metabolism-related pathways. qRT-PCR further confirmed the upregulation of key genes, including NDUFS2, VDAC3, ANXA2, MTHFD1L, and SCD. Overall, 75 μM cysteine improves bovine oocyte IVM quality by enhancing antioxidant capacity, improving mitochondrial membrane potential, increasing lipid-derived energy substrate storage, and regulating genes related to energy metabolism and developmental competence. Full article

Probiotics are considered promising feed additives for enhancing fish health and production performance in aquaculture. This study evaluated the effects of dietary supplementation with Sporolactobacillus laevolacticus on growth performance, feed utilization, intestinal health, and physiological responses in juvenile coho salmon (Oncorhynchus kisutch). Fish were fed a control diet or diets supplemented with S. laevolacticus at 0.89 × 10⁷, 0.90 × 10⁹, or 0.87 × 10¹¹ CFU/g for 10 weeks. Compared with the control, S. laevolacticus supplementation significantly increased final body weight, weight gain rate, specific growth rate, and protein efficiency ratio, while decreasing the feed conversion ratio (p < 0.05). It also significantly enhanced intestinal protease and α-amylase activities, improved serum biochemical and immune-related parameters, and promoted better intestinal morphology (p < 0.05). Additionally, S. laevolacticus supplementation led to elevated expression of antioxidant-related genes, reduced expression of pro-inflammatory genes, and altered gut microbial composition, characterized by a decrease in Proteobacteria and increases in Firmicutes and Lactobacillales. Among the tested dosages, 0.90 × 10⁹ CFU/g produced the most consistent improvements in growth performance, digestive function, intestinal health, antioxidant and immune responses, and gut microbial composition, and was therefore identified as the optimal supplementation level. Collectively, dietary S. laevolacticus at 0.90 × 10⁹ CFU/g improved growth performance and intestinal health in juvenile coho salmon, highlighting its potential as a probiotic candidate for coho salmon aquaculture. Full article

Phenolic compounds, particularly secoiridoids derived from oleuropein and ligstroside, are the main determinants of the antioxidant capacity and health-promoting properties of virgin olive oil, yet their content is strongly affected by processing conditions. This study aimed to enhance phenolic enrichment in Picual olive oil through mild acidification of the paste. Four olive samples were processed under a Central Composite Design varying malaxation time (40–80 min), acid concentration (0.02–0.08 mol/kg paste), and acid type (ascorbic or malic), across two maturity indices (MI) per acid, and evaluated by Response Surface Methodology. Ascorbic acid outperformed malic acid for most of the evaluated responses, with the majority of the monitored parameters exhibiting progressive improvements with increasing acid concentration across the tested range. Extraction efficiency reached 75.8–80.0%, increasing with ripening, malaxation time, and acid dose. Acidification did not affect standard quality parameters but enhanced pigment retention (up to 18.9 mg/kg carotenoids; 28.9 mg/kg chlorophylls) and selectively increased oleuropein- and ligstroside-derived secoiridoids. Antioxidant capacity correlated with phenolic content, reaching 1177.9 µmol Trolox equivalents/kg at high acid concentration and medium–high malaxation times. The optimal acid dose depended on MI, with higher doses favoring riper fruit. Overall, in the Picual cultivar, mild acidification is an effective strategy to enrich the antioxidant fraction of olive oil without compromising its quality. Full article

Light irradiance and spectral quality are key environmental factors that influence the growth, photosynthetic performance, and metabolic responses of cyanobacteria. In this study, the effects of increasing white and PAR-red light irradiances on Anabaena variabilis were evaluated in repeated-batch cultures, focusing on photosynthetic efficiency, biomass productivity, and the modulation of antioxidant systems, while cultures maintained under constant irradiance were used as control. Results showed that A. variabilis can maintain photosynthetic efficiency, as indicated by F_V/F_M values, within the optimal range for healthy cultures despite variations in light conditions. PAR-red light, in particular, enhanced biomass productivity and induced stronger photoacclimation responses compared to white light. Moreover, analysis of chlorophyll fluorescence (JIP parameters) revealed that photosynthetic machinery adapts to increased irradiance by modulating energy fluxes. Dissipated energy (DI₀/RC) increases by 4.5-fold under increasing PAR-red light with respect to control cultures, which suggests that PAR-red light promotes thermal dissipation of excess absorbed energy at the phycobilisome level, independently of and complementarily to, the increase in light-harvesting antenna pigments (chlorophylls and phycobiliproteins), thereby reducing the net oxidative pressure in the electron transport chain. The increase in photosynthetic pigments reflects an adaptive adjustment to optimize light harvesting under red light, with a phycocyanin content of 123 mg·g⁻¹ biomass, 30% higher than that obtained in control culture. Overall, A. variabilis demonstrated a robust capacity to acclimate increasing light irradiance and varying light quality through coordinated photoacclimation and antioxidant responses, in repeated-batch cultures. These findings highlight its physiological flexibility, which can be properly driven to maximize the production of valuable bioactive compounds, particularly phycobiliproteins such as phycocyanin, with applications in biotechnology. Full article

Mung bean (Vigna radiata (L.) Wilczek) seed coat (MBSC) is an underutilized by-product rich in vitexin and isovitexin, but its potential as a source of spray-dried functional powders has not been systematically evaluated. This study investigated the spray drying of MBSC extract using three structurally distinct polysaccharide-based carriers—maltodextrin, trehalose, and inulin—to compare their effects on process yield, powder quality, and the content of phenolic compounds, flavonoids, and antioxidant activity. Response surface methodology (RSM) with a Box–Behnken design was employed to examine the influence of inlet temperature (130–160 °C) and carrier concentration. Maltodextrin provided the highest process yield (84.85%), while trehalose and inulin formulations exhibited stronger antioxidant activity, with the lowest DPPH IC₅₀ values of 0.096 mg/mL and 0.100 mg/mL, respectively (expressed per mg of spray-dried powder). Trehalose yielded the highest total phenolic content (TPC = 28.12 mg GAE/g extract) and acceptable flowability (Carr’s index = 20.72%). Inulin gave the highest total flavonoid content (TFC = 126.8 mg QE/g extract) but showed greater variability, attributed to its polymeric network and higher hygroscopicity. The RSM models showed high predictive accuracy for TPC (R² > 0.98) and DPPH antioxidant activity (R² ≈ 1.00). These findings offer a multi-objective optimization framework that links carrier structure to powder performance, providing practical guidance for selecting polysaccharide carriers in the development of spray-dried nutraceutical and functional food ingredients. However, direct measurement of encapsulation efficiency, particle morphology, and storage stability was beyond the scope of this study and warrants further investigation. Full article

Ganoderma lucidum spores protein (GLSP) holds significant potential for providing antioxidant peptides. We employed in silico enzymatic hydrolysis to generate small peptide fragments by specific proteins. Through fast computer screening and molecular docking with Keap1 receptor, we identified two potential antioxidant peptides, KAF (Lys-Ala-Phe) and NDSF (Asn-Asp-Ser-Phe), from 1171 candidates after efficient hydrolysis by pepsin and proteinase K. Molecular docking result showed both of them could bind onto the Leu557, Ala 510 and Val512 of bioactive pockets of Keap1 through hydrogen bonds and NDSF had lower docking energy (−85.6073 kcal/mol). The in vitro antioxidant validation indicated both of them could eliminate DPPH and ABTS radicals dramatically, and NDSF had a stronger scavenging capacity on DPPH (IC₅₀ = 35.1 μg/mL) and ABTS (IC₅₀ = 55.9 μg/mL), respectively. Quantitative chemical analysis further revealed that the key antioxidant active sites of NDSF were located at O18 of Ser amino side chain, and N9 of Lys terminal amino residue for KAF. Furthermore, in the cellular experiments, NDSF and KAF effectively increased the activities of antioxidant enzymes such as SOD, CAT, and GPx, while also reducing the level of MDA. Together, these findings highlight the potential of Ganoderma lucidum spore proteins as a source for the rapid identification of antioxidant peptides. The two selected peptides, therefore, s hold promising prospects for applications in functional foods and health products. Full article