Search Results (7,742)

Radiation-induced liver disease (RILD) remains a clinically significant complication of radiotherapy for malignant neoplasms of the liver and upper abdomen, restricting achievable therapeutic doses and adversely affecting patient outcomes. Conventional photon-based radiotherapy (X-rays/γ-rays) exposes substantial volumes of healthy liver parenchyma and adjacent organs to ionizing radiation, increasing the risk of hepatocellular damage, inflammation, and progressive fibrosis. Electron irradiation (β-particles) represents a promising alternative owing to its limited tissue penetration (~2–3 cm) and steep dose fall-off, which significantly reduces exit dose and may reduce exit dose and limit exposure of paratumoral healthy tissues compared with photon therapy. However, the molecular mechanisms underlying electron-induced hepatic damage and strategies for its prevention remain insufficiently characterized. This review systematically analyzes the pathogenesis of radiation-induced liver damage, encompassing direct DNA damage, oxidative stress, mitochondrial dysfunction, NF-κB-mediated inflammation, cellular senescence, and TGF-β/Smad-driven fibrosis. The comparative dosimetric and radiobiological advantages of electron irradiation over photon therapy are discussed, with particular attention to intraoperative radiotherapy, FLASH, and very high-energy electron techniques. Current radioprotective strategies are critically evaluated, with emphasis on the limitations of amifostine and the multifunctional radioprotective potential of ascorbic acid, including free radical scavenging, attenuation of lipid peroxidation, stimulation of endogenous antioxidant defense, and direct inhibition of radiation-induced DNA strand breaks. Existing gaps in the evidence base are identified, and recommendations for future experimental and clinical research are proposed. Full article

Anthocyanins are water-soluble plant pigments. They give many plants, fruits, vegetables, and cereal kernels their red, purple, and blue colors. This research aims to reveal the biological properties of peonidin as an anthocyanin. To comprehend the antioxidant capabilities of peonidin, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS^•+), N,N-dimethyl-p-phenylenediamine dihydrochloride radical (DMPD^•+), and 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH^•) scavenging, Fe³⁺-2,4,6-tris(2-pyridyl)-s-triazine (TPTZ), and Cu²⁺ reducing assays were recorded. The IC₅₀ values for peonidin against ABTS^•+, DMPD^•+ and DPPH^• scavenging capabilities were determined to compare with standard antioxidants. ABTS^•+ radical scavenging activity of peonidin had an IC₅₀ value of 15.40 μg/mL, while the IC₅₀ values for BHA, BHT, Trolox, and α-Tocopherol were 12.82, 11.78, 12.67, and 10.83 μg/mL, respectively. DPPH radical scavenging activity of peonidin had an IC₅₀ value of 41.63 μg/mL, while the IC₅₀ values for BHA, BHT, Trolox, and α-Tocopherol were 8.45, 23.10, 6.30, and 18.73 μg/mL, respectively. Enzyme inhibition was studied to investigate the effects of peonidin. The K_i values of peonidin were 114.33, 63.02, 2.99, 9.76, and 15.14 nM toward hCA I, hCA II, AChE, BChE, and α-glycosidase enzymes, respectively. Furthermore, peonidin’s interactions with target enzymes BChE, hCA I, hCA II, AChE, and α-glycosidase were investigated by molecular docking. The results suggest that antioxidant-rich peonidin is a plant-based compound with potential use in the treatment of glaucoma, Alzheimer’s disease, and diabetes. Full article

The composition of ginsenosides is closely associated with antioxidant activity, but the effects of variety and growth year on the accumulation of individual ginsenosides and their quantitative relationships with free radical scavenging activity remain unclear. In this study, six ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) in cultivated ginseng (Panax ginseng C. A. Mey.) and American ginseng (Panax quinquefolius L.) were quantified by HPLC, combined with DPPH and ABTS assays, and systematically analyzed using PCA, OPLS-DA, HCA, and PLSR. The results showed that variety exerted a much greater influence than growth year. American ginseng contained significantly higher levels of PPD-type ginsenosides (Rb1, Rd, Rc), while Rg1 was more abundant in cultivated ginseng. OPLS-DA clearly distinguished the two varieties based on ginsenoside profiles, with Rc, Rb1, and Rd identified as key marker ginsenosides (VIP > 1). Ginsenoside extracts showed scavenging abilities against both DPPH and ABTS. However, the PLSR model only successfully yielded predictive capability for DPPH. The poor prediction for ABTS suggested that ABTS scavenging may be attributed to other untested constituents in the extracts. This study provides a robust basis for variety-oriented quality control and antioxidant efficacy evaluation in ginseng products. Full article

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and is frequently diagnosed at advanced stages, thereby limiting curative treatment options. Although interventions with curative intent, such as liver resection and ablation, are available, recurrence rates exceed 70%. Recent developments in HCC management have shifted the focus from conventional surgery and targeted therapies to immunotherapy. This review synthesizes current evidence on immunotherapy for curative purposes in HCC, including both neoadjuvant and adjuvant strategies. It evaluates completed and ongoing clinical trials of immune checkpoint inhibitors (ICIs), administered as monotherapy or in combination with anti-angiogenic agents or dual-checkpoint blockade. ICIs may transform the initial treatment paradigm for advanced HCC, although their applications remain in the investigational stage. Preliminary results from the IMbrave050 trial suggested that adjuvant immunotherapy following radical liver resection improves recurrence-free survival (RFS) in high-risk patients. However, the initially promising outcomes of the combination of atezolizumab and bevacizumab compared with active surveillance were not sustained in the median follow-up, and long-term survival results are awaited. Although several studies have demonstrated encouraging preliminary results, a clear survival benefit has not yet been established. Further studies are necessary to establish definitive conclusions. Immunotherapy has a pathophysiological basis and preliminary evidence to redefine HCC management across disease stages; its integration into pre- and post-operative strategies may increase resectability, reduce recurrence, and improve survival. Ongoing trials are expected to clarify its exact role. Full article

Wolffia globosa (watermeal) is a potential plant-based food ingredient. This study characterized its nutritional and physicochemical properties, elemental levels, total phenolic content (TPC), total flavonoid content (TFC), DPPH radical-scavenging activity, IL-6 production in H₂O₂-stimulated RAW264.7 macrophages, and preliminary cell-viability responses. On a dry-weight basis, the tested W. globosa sample contained 25.83% protein, 4.56% fat, 16.58% ash, 8.80% crude fiber, and 44.22% carbohydrate. Arsenic and zinc were detected below their limits of quantification, whereas cadmium, copper, and lead were below their method detection limits. All analytical reporting limits were below the corresponding EFSA specification values. The extract had TPC and TFC values of 0.85 ± 0.03 mg GAE/g sample DW and 0.52 ± 0.02 mg QE/g sample DW, respectively, and showed weak DPPH radical-scavenging activity (IC₅₀ = 7.58 ± 0.32 mg DW-equivalent/mL). At 0.1 mg DW-equivalent/mL, the H₂O₂-stimulated extract-treated group showed a lower IL-6 concentration than the H₂O₂-stimulated extract-free model control. Weak reductions in cancer-cell viability occurred only at high concentrations (IC₅₀ values of approximately 38–42 mg DW-equivalent/mL). The biological findings remain preliminary. Overall, the tested sample showed promising nutritional and physicochemical characteristics, low selected-elements levels, and preliminary in vitro responses. Full article

The Escherichia coli adenine-DNA glycosylase (MutY) and its human homologue, MUTYH, protect cells against oxygen-free radical-induced mutagenesis by excising regular adenine impaired with 8-oxo-7,8-dihydro-guanine (8oxoG) in the base excision repair (BER) pathway. However, removal of adenine by MutY and MUTYH from an A·8oxoG pair generated via misincorporation of an oxidized nucleotide during DNA synthesis might induce A·T→C·G transversions. Here, to examine MutY and MUTYH in vitro activities, we used short synthetic DNA duplexes in which the target adenine residue was positioned opposite a variety of DNA base modifications. MUTYH does not excise mismatched adenine in non-canonical DNA substrates, whereas MutY excises adenine mispaired with 1,3-d(GpNpG) cisplatin intra-strand crosslink. In addition, we characterized four MUTYH variants associated with cancer risk, which exhibit the following order of DNA glycosylase deficiency: WT ≥ G169D > G202E ≈ Y165C >> D222N. Human adenine-DNA glycosylase MUTYH and its mutant variants, contrary to bacterial MutY, are not prone to aberrant removal of regular adenine residues opposite modified residues in DNA duplexes. We hypothesize that E. coli MutY is prone to aberrant repair under certain conditions and that this may prevent incorporation of adenine opposite blocking lesions in the template strand. Full article

Background: Patients with end-stage renal disease (ESRD) undergoing radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC) represent a uniquely high-risk population. While prior studies have demonstrated worse postoperative outcomes among dialysis-dependent patients, no study has systematically compared oncological outcomes between peritoneal dialysis (PD) and hemodialysis (HD) modalities following RNU. This multicenter study evaluates whether dialysis modality (peritoneal dialysis versus hemodialysis) acts as an independent prognostic factor following radical nephroureterectomy. Methods: Using the Taiwan UTUC Collaboration Group Registry—a multicenter, nationwide database comprising 21 tertiary and regional medical centers —we identified 350 ESRD patients who underwent RNU for UTUC between September 1988 and December 2023. Patients were categorized by dialysis modality at the time of surgery: 310 on HD and 40 on PD. Propensity score overlap weighting was applied to account for baseline differences. Multivariate Cox proportional hazards and Fine-Gray competing risk regression models were utilized to evaluate overall survival (OS), cancer-specific survival (CSS), progression-free survival (PFS), and non-UTUC mortality. Results: After overlap weighting, PD was independently associated with significantly worse OS (HR = 2.34, 95% CI 1.29–4.25, p = 0.005) and PFS (HR = 2.06, 95% CI 1.16–3.66, p = 0.013) compared to HD and exhibited a trend toward worse CSS in univariate analysis (log-rank p = 0.094). Survival curve divergence between PD and HD was most pronounced from 12 to 24 months post-surgery onward. Notably, this survival disadvantage persisted despite PD patients being significantly younger (mean age 58.8 vs. 65.1 years) and receiving adjuvant chemotherapy more frequently (20.0% vs. 6.5%). PD was also independently associated with higher non-UTUC mortality on multivariate competing risk analysis (sHR = 2.17, 95% CI 1.22–3.88, p = 0.009). Conclusions: In this first multicenter systematic comparison of PD versus HD patients undergoing RNU for UTUC, PD modality was independently associated with worse OS and PFS and exhibited a trend toward worse CSS in univariate analysis, compared to HD. This survival disadvantage persists despite favorable baseline characteristics and higher rates of adjuvant chemotherapy. We hypothesize these outcomes may be driven by a dual vulnerability: impaired systemic tumor control and elevated non-cancer mortality following surgical disruption of the peritoneal environment. To mitigate these risks, prioritizing minimally invasive or retroperitoneal surgical approaches to preserve peritoneal integrity, combined with modality-specific multidisciplinary surveillance, is recommended. Full article

In a previous clinical trial, it was shown that a probiotic blend (Bifidobacterium longum CECT 7347 (Esflorin1™), Lacticaseibacillus rhamnosus CECT 8361 (BPL15) and Lacticaseibacillus casei CECT 9104 (BPL4)) reduced oxidative stress in males engaging in intense exercise. The present study evaluated whether the probiotic blend’s functional properties are preserved after heat treatment and investigated the underlying mechanism of action using preclinical models. The antioxidant, immunomodulatory and intestinal effects of the heat-treated and probiotic blends were assed using in vitro assays and Caenorhabditis elegans (C. elegans) models. The heat-treated blend preserved the antioxidant activity by scavenging free radicals, reducing intracellular reactive oxygen species and enhancing survival in C. elegans under oxidative stress, possibly via sod-3 upregulation in the CF1553 strain. It also enhanced mitochondrial biogenesis and ATP production in C2C12 via AMPK phosphorylation. Both versions attenuated a gut inflammatory response, improved intestinal barrier in Caco-2 cells and C. elegans and exhibited immunomodulatory activity in U937 macrophages at the tested concentrations. These findings support the heat-treated blend as a promising postbiotic supplement to manage oxidative stress and other physiological alterations associated with intense exercise. Full article

Prostate cancer remains a major clinical challenge, partly due to tumour–immune interactions that contribute to immune evasion and therapeutic resistance. The CD47–SIRPα axis is a key macrophage-associated immune recognition pathway; and materials-oriented platforms that allow preliminary investigation of tumour–macrophage interaction patterns remain valuable. Here, we report an optically traceable biohybrid nanoplatform based on CD47 aptamer-functionalized fluorescent carboxyl-functional MMES-POSS hybrid nanoparticles. The nanoparticles were synthesized within 5 min using UV-induced free-radical emulsion polymerization in an ethanol–water system and exhibited spherical morphology, SEM-derived dry-state mean diameters below 100 nm, negative surface charge, and retained fluorescence due to RITC encapsulation within the crosslinked hybrid matrix; however, DLS measurements revealed pronounced aggregation and polydispersity in aqueous dispersion. SEM and EDX provided complementary evidence of nanoparticle morphology and elemental composition, whereas zeta potential and Nanodrop measurements provided evidence consistent with surface functionalization, and FTIR confirmed retention of the core POSS, carbonyl, and RITC-associated chemistry. In a PC-3/THP-1 macrophage co-culture model, Annexin V–FITC/PI flow cytometry showed a concentration-dependent redistribution of cell populations, with the most pronounced early apoptotic enrichment observed at 2 µg/mL. However, pairwise exploratory comparisons among concentrations did not reach statistical significance, and this is discussed as a limitation of the present exploratory dose–response characterization. These findings indicate preliminary interaction-associated response patterns rather than definitive receptor-specific targeting or therapeutic CD47–SIRPα blockade. Overall, this modular POSS-based biohybrid interface provides a materials-oriented platform for probing prostate cancer–macrophage interaction profiles and guiding future mechanistic validation studies. Full article

The successful use of Assisted Reproductive Technologies (ARTs) such as artificial insemination (AI) in small ruminants and other mammals depends on many factors, the most important of which is the quality of the semen used. The liquid storage and cryopreservation of spermatozoa at lower temperatures are associated with artificial insemination and rapid genetic improvement programs in the sheep production industry. Several studies have reported increased lipid peroxidation (LPO) and highly reactive oxygen species (ROS) production during liquid storage or cryopreservation of ram semen, leading to oxidative stress (OS), decreased antioxidant defense, and changes in sperm quality parameters like biokinetic and biochemical characteristics, viability, functional membrane and DNA integrity, along with mitochondrial activity. Therefore, supplementing ram semen extenders with exogenous antioxidants before preservation could mitigate this harmful effect. Various in vitro studies have reported improvements in ram sperm quality parameters like motility indexes, vitality, functional membrane/DNA integrity, antioxidant enzyme activity, total antioxidant content, mitochondrial activity, in vivo/in vitro fertility with significant decline in sperm abnormality, free radical production, LPO, ROS, apoptosis rate, and cytochrome C release from the mitochondrial matrix after the addition of various natural and synthetic antioxidant (vitamins, glutathione, taurine, pyruvate, melatonin, cysteine, selenium, zinc, plant extracts, sugars, amino acids, polyphenols) substances during preservation. Therefore, this review summarizes recent findings on oxidative stress-induced damage to sperm quality parameters in various ram breeds during chilling storage and cryopreservation. Moreover, supplementing basic semen extenders with different non-enzymatic antioxidant substances as a method to maintain sperm quality—along with their efficacy in reducing or preventing sperm damage during preservation—was discussed in detail. Full article

Hydrogen sulfide (H₂S), a high-volume by-product of the hydrodesulfurization of fossil fuels, can be valorized by thermolysis to recover both molecular hydrogen and elemental sulfur, rather than being oxidized as in the conventional Claus process. The viability of this route depends on quantitative knowledge of the reaction mechanism and of the energy costs of dissociation, which are difficult to obtain experimentally at the temperatures involved. Here we study H₂S thermolysis by reactive molecular dynamics (RMD) with the ReaxFF potential for systems of 1000 H₂S molecules at 1 atm, addressing three coupled questions: the simulation parameters required for dilute gases, the energetics of dissociation, and the elementary reaction mechanism. The interaction cutoff radius proved critical: the original 10 Å value, parametrized for condensed systems, misses about 23 eV of attractive non-bonded interaction energy in the gaseous system at 298.15 K (≈0.023 eV per molecule) and fails to capture dissociation at 3000 K within 20 ns, whereas radii of 30–40 Å converge. Using a 40 Å cutoff at 2500, 3000 and 3500 K, atom-resolved species-transition records reveal a free-radical chain mechanism built from the same set of elementary steps at the three temperatures, whose relative contributions shift with temperature: S–H homolysis initiates the chain, hydrogen abstraction (H• + H₂S → H₂ + HS•) is essentially the exclusive source of H₂ (persistent H• + H• recombination contributed only 1, 13 and 17 events, below 0.5% of the abstraction count), and a slow sulfur-condensation stage (S₂ → S₃ → S₄) limits the net conversion, which reached 9.3 ± 0.9%, 26.3 ± 1.4% and 46.7 ± 1.6% within the simulated windows (single-trajectory counting resolution)—kinetically limited values, not equilibrium conversions. The enthalpy of the system rises linearly with the number of H₂S molecules consumed (R² ≥ 0.99), defining energy costs of 2.46 ± 0.04, 3.10 ± 0.08 and 3.95 ± 0.18 eV per molecule that increase with temperature by ≈1.48 eV per 1000 K; at 3500 K the cost lies between the 0 K complete-dissociation limit D₀ = 3.90 eV derived from the experimental H–SH bond energy and the Kirchhoff-corrected complete-dissociation enthalpy at that temperature (4.11–4.12 eV), statistically indistinguishable from the latter (a 0.9σ difference). These results provide a thermochemically validated, molecular-level basis for engineering the valorization of residual H₂S as a source of green hydrogen. Full article

In this study, we synthesized a lignin-based superabsorbent hydrogel (LWR) to relieve severe evaporation and structural degradation in inland saline–alkali soils. The LWR was prepared via free-radical graft copolymerization of calcium lignosulfonate (CL) and acrylic acid (AA), with its swelling performance optimized systematically. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize its chemical and microscopic structure, and the soil column was exposed to three drying–wetting cycles to explore the effects of hydrogel dosage on soil evaporation and crack evolution. CL may graft into polyacrylic acid under optimal conditions (60% AA neutralization, 4% CL, 1% initiator, and 0.03% crosslinker) to form a porous hydrophilic 3D network. Consequently, the optimized LWR achieved swelling capacities of 1480 g/g and 122 g/g in deionized water and a 0.9% NaCl solution, respectively, showing high water absorbency and salt resistance. During cyclic drying and wetting, soil evaporation was first dominated by the hydrogel’s water retention capabilities; then, it was controlled physically by soil surface cracks. A moderate LWR dosage of 0.3% was used to maintain stable water retention in soil and the intact soil structure, which likely occurred due to its strong water absorption and hypothesized calcium ion bridging anti-cracking interactions. This work overturns the traditional view that a higher hydrogel dosage yields better water retention. Instead, it highlights the importance of conducting a long-term joint evaluation of the hydrogel’s water retention capacity and its resistance to soil dry–wet deformation stress, thereby offering theoretical support for eco-friendly water retention agent design and saline–alkali land remediation. Full article

Polystyrene (PS) thermal degradation involves localized molecular bond-cleavage events that are not directly equivalent to the apparent kinetic parameters obtained from bulk thermal analysis. In this study, a finite hydrogen-terminated PS oligomeric model was examined using density functional theory at the M06-2X/LANL2DZ level, whereas the non-isothermal degradation behavior of a PS sample was independently evaluated by thermogravimetric analysis under nitrogen. The computational analysis considered frontier molecular orbital distributions and site-specific thermodynamic descriptors associated with homolytic C–C cleavage and radical-mediated β-scission reactions. The calculated HOMO–LUMO gap of 742.62 kJ mol⁻¹ indicated a comparatively large orbital-energy separation within the selected oligomeric model, while the localization of the frontier orbitals over aromatic and benzylic regions revealed a spatially heterogeneous electronic distribution. Homolytic C–C cleavage exhibited bond dissociation energies ranging from 414.09 to 481.24 kJ mol⁻¹, demonstrating that the thermodynamic requirement for radical generation depends on the local molecular environment of the evaluated structure. The Gibbs free-energy changes calculated for the selected radical β-scission reactions ranged from 55.44 to 189.41 kJ mol⁻¹. These quantities represent model-dependent reaction thermodynamics and should not be interpreted as activation barriers because transition states were not calculated. Thermogravimetric analysis showed systematic increases in Tonset and Tmax with increasing heating rate, consistent with kinetic delay and thermal-lag effects under non-isothermal conditions. The Kissinger method yielded a global apparent activation energy of 186.61 kJ mol⁻¹, whereas the residual-mass-corrected Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose methods produced average apparent activation energies of 180.81 and 178.49 kJ mol⁻¹, respectively, over α = 0.05–0.95. Across the same conversion interval, the FWO apparent activation energy increased from 143.10 to 221.71 kJ mol⁻¹, while the KAS values increased from 140.10 to 220.23 kJ mol⁻¹, indicating an evolving macroscopic degradation response with greater uncertainty toward high conversion. The computational and experimental datasets were therefore interpreted as complementary but non-equivalent scale-dependent descriptions: DFT compares the relative thermodynamics of selected molecular reactions within a finite isolated oligomer, whereas TGA characterizes the global apparent kinetic behavior of the condensed polymer sample. No direct numerical correspondence was established between the molecular reaction energies and the TGA-derived apparent activation energies, and no individual cleavage reaction was assigned to a specific conversion interval. Extrapolation of these results to high-molecular-weight, polydisperse, additive-containing, cross-linked, or environmentally aged PS microplastics should therefore be made with caution. Full article

Pleurotus ostreatus (shimeji) is an edible mushroom widely recognized for its nutritional value and production of bioactive compounds. In addition to its fruiting body, mycelial biomass has emerged as a promising and sustainable alternative to produce bioactive compounds under controlled cultivation conditions. This study evaluated the nutritional composition, texture profile, biochemical composition, phenolic compounds, and antioxidant properties of the mycelium of P. ostreatus. Nutritional parameters were determined by FoodScan™ (NIR), while biochemical composition was assessed through spectrophotometric quantification of soluble proteins, free amino acids, reducing sugars, and total carbohydrates. Texture Profile Analysis (TPA) was performed to characterize the mechanical and technological properties of the mycelial biomass. Total phenolic compounds were quantified using the Folin–Ciocalteu method, and individual phenolics were identified by HPLC-DAD. Antioxidant activity was evaluated by ABTS, DPPH, TEAC, and hydroxyl radical scavenging assays. The mycelium exhibited high moisture content and relevant protein levels, as well as a rigid structural profile characterized by elevated hardness and gumminess. Biochemical characterization revealed considerable concentrations of soluble proteins and free amino acids, together with detectable levels of reducing sugars and total carbohydrates. The aqueous extract showed high total phenolic content and expressive antioxidant activity, with gallic acid identified as the predominant phenolic compound, followed by ferulic acid. The extracts also demonstrated efficient radical scavenging capacity in ABTS, DPPH, and hydroxyl radical assays. These findings highlight P. ostreatus mycelium as a sustainable source of bioactive compounds with potential applications as a functional ingredient in food, nutraceutical, and biotechnology sectors, reinforcing its role within circular bioeconomy strategies. Full article

Quercetin is a nutraceutical flavonoid whose aqueous use is limited by poor solubility and chemical instability. Existing polysaccharide carriers may require chemical modification, crosslinkers, multicomponent formulations, or complex processing. Here, alkali-neutralization-induced β-1,3-1,6-glucan nanoparticles (r-glucan NPs), prepared from Aureobasidium pullulans K-1 glucan, were compared with β-cyclodextrin (β-CD), using native t-glucan as a composition-matched control. Spectroscopic analyses supported quercetin association with chiral, cavity-rich domains of r-glucan NPs. r-Glucan NPs showed higher quercetin loading than β-CD and increased apparent aqueous solubility/dispersibility to 1620 ± 15.3 µM, compared with 256 ± 0.52 µM for the native β-1,3-1,6-glucan control, 347 ± 16.4 µM for β-CD, and 7.11 ± 3.97 µM for free quercetin. The t-glucan control initially retained quercetin but showed limited aqueous dispersibility and formed a visible precipitate within 3 days in 1 vol% ethanol. Although carrier association reduced oxygen radical absorbance capacity (ORAC) activity on an equal-quercetin basis, r-glucan NPs yielded a maximum ORAC value of 11,600 ± 1200 µmol TE L⁻¹, compared with 815 ± 235 for β-CD and 368 ± 38.2 for free quercetin. r-Glucan NPs also improved apparent retention, photostability, stability at pH 6.8, and cellular antioxidant activity relative to free quercetin. These results support r-glucan NPs as food-compatible carriers for aqueous quercetin delivery. Full article