Search Results (176)

Antimony micro/nanoparticles (Sb MNPs) are key environmental Sb species that enter the human body via inhalation, ingestion, and dermal contact, posing potential health risks. Their complex transformation across multiple Sb species hinders accurate quantification, leaving their in vivo transformation mechanisms poorly understood. In this study, in vitro respiratory, gastrointestinal, and sweat models were established to investigate Sb MNP biotransformation, and the gastrointestinal model incorporated human fecal suspension to better mimic in vivo conditions. Transformation dynamics showed that simulated gastric fluid dissolved Sb₂O₃, Sb₂S₃ and Sb₂O₅ MNPs into ionic Sb without altering valence states, while Sb ions remained at low levels. Gastric-derived Sb(III) was oxidized to less toxic Sb(V) in the intestinal phase. In simulated sweat, Sb(III) concentrations increased but accounted for only 1.75% of total exposure, indicating low dermal risk. Notably, Sb₂O₃ MNPs exhibited lability in simulated lung fluids, particularly artificial lysosomal fluid (ALF), where dissolved Sb(III) reached 1276.7 μg/L with an ionic release rate of 63.8%. The low pH of ALF and formation of stable soluble complexes with citrate, lactate, and Cl⁻ might drive Sb₂O₃ dissolution, suggesting high inhalation risk. This study advances the quantitative understanding of Sb MNP biotransformation and thus for human health risk assessment. Full article

Background/Objectives: Mpox (formerly monkeypox) is a re-emerging global health threat. While current vaccines are injectable, oral vaccination offers a painless alternative, though the harsh gastrointestinal (GI) environment challenges live viral vaccines. This study evaluated the stability of orthopoxviruses under simulated GI conditions to assess the physicochemical feasibility of oral mpox immunization. Methods: Attenuated and virulent strains of vaccinia, cowpox, and camelpox viruses were exposed to simulated gastric (pH 1.0–2.0 and 3.0–4.0 with pepsin) and intestinal (pH 7.0–7.5) conditions at 37 °C for 180 min. Viral titers were determined via cell culture assays. The physicochemical protective efficacy of enteric-coated capsules was evaluated using standard dissolution testing parameters. Results: All orthopoxviruses were rapidly inactivated under highly acidic fasting conditions (pH 1.0–2.0). However, they exhibited high stability at pH 3.0–4.0 and 7.0–7.5, retaining approximately 20–30% of their initial infectivity after 180 min. Enteric-coated capsules successfully maintained shell integrity in simulated gastric fluids for over 3 h and dissolved completely under intestinal conditions within ~130 min, aligning with small intestine transit times. Conclusions: Orthopoxviruses possess sufficient intestinal stability to support the physicochemical feasibility of oral immunization, provided they are protected from gastric acidity. Enteric-coated capsules represent a highly suitable delivery system for the intestinal release of live orthopoxvirus-based candidates, warranting further in vivo preclinical evaluation. Full article

The survival of Candidozyma (Candida) auris under gastric conditions remains poorly understood, particularly in veterinary species. This pilot in vitro study evaluated the resistance of two cat-derived C. auris strains and Candida parapsilosis ATCC 22019 in simulated gastric fluid (SGF). Yeast suspensions were exposed to SGF adjusted to pH 1–5 and 7 for up to 4 h at 37 °C, and colony-forming units (CFUs) were enumerated at 1, 2, and 4 h. Results were expressed as mean log10 CFU/mL ± standard deviation. A clear pH-dependent effect was observed: At pH 7, all strains showed increased CFU counts over time, whereas acidic conditions induced a marked reduction in culturability. At pH 1, reductions of approximately 3–4 log10 units occurred within 1 h, while at pH 2–5 a more moderate decrease of about 1 log10 unit was observed, with most reduction occurring early and stabilizing over time. Two-way ANOVA confirmed significant effects of pH and exposure time, with a significant interaction for all strains (p < 0.0001). Overall, gastric-like acidity strongly reduced, but did not completely abolish, the culturability of the two feline C. auris isolates under the specific in vitro conditions tested. Further studies using larger isolate collections and more physiologically relevant gastrointestinal models are needed to determine whether these findings translate into in vivo survival, intestinal transit, or colonization. Full article

Oral enzyme replacement therapy for lactase deficiency is limited by the rapid degradation of free β-galactosidase in the gastrointestinal tract. To overcome this, β-galactosidase was encapsulated into polyelectrolyte microcapsules (PMCs) via layer-by-layer assembly using MnCO₃ sacrificial templates, with CaCO₃-based PMCs as a reference. MnCO₃-PMCs achieved 99.4% encapsulation efficiency and retained 85.8% of initial activity, significantly outperforming CaCO₃-PMCs (86.0% and 29.7%). Under simulated gastric conditions (pH 2.0, pepsin), the free enzyme and CaCO₃-PMCs were completely inactivated, whereas MnCO3-PMCs preserved ~86% activity. In simulated intestinal fluid, MnCO₃-PMCs exhibited a 4.3-fold activity increase within the first hour and maintained a 2.5-fold enhancement after 70 h, while the free enzyme progressively inactivated. Furthermore, MnCO₃-PMCs demonstrated superior storage stability, retaining 64% of initial activity after 90 days at 4 °C, compared with 25% for CaCO₃-PMCs. Although immobilization increased the Michaelis constant, the shift was smaller for MnCO₃-PMCs (8.9-fold) than for CaCO₃-PMCs (15.2-fold). In conclusion, MnCO₃-templated PMCs effectively protect β-galactosidase from gastrointestinal degradation, sustain prolonged catalytic activity, and offer excellent storage stability, highlighting their strong potential for improving oral enzyme replacement therapy in lactose intolerance. Full article

Background: Calcium formulations are important nutritional interventions for improving insufficient calcium intake and assisting in the prevention and treatment of osteoporosis. In vitro and in vivo performance may be influenced by dosage form, calcium source, and formulation composition. In this study, an integrated approach combining in vitro dissolution, pharmacokinetic, and pharmacodynamic evaluations was used to compare the comprehensive performance of nine calcium formulations and related functional components. Methods: The nine samples were coded as CS-1 to CS-9 according to a predefined order. Calcium release characteristics were determined under simulated gastrointestinal pH conditions using a flow-through cell system. Calcium concentrations in rat plasma, feces, and urine were measured by inductively coupled plasma optical emission spectrometry (ICP-OES) to evaluate calcium exposure, excretion, and retention. Meanwhile, the bone-protective effects of different calcium preparations were assessed in a retinoic acid-induced osteoporotic ICR mouse model, and the pharmacodynamic performance of calcium citrate and various bone-derived peptide preparations was investigated in a calcium-deficient female Sprague–Dawley (SD) rat model. Results: CS-1 exhibited rapid and nearly complete calcium release in simulated gastric fluid and showed a relatively favorable dissolution profile under sequential gastrointestinal pH conditions. Calcium balance analysis indicated that calcium retention in rats was relatively higher after administration of CS-1. Animal experiments showed that different calcium sources and bone-derived peptide preparations improved bone-related parameters to varying degrees, among which CS-1 produced relatively consistent improvements in bone microarchitecture and biomechanical properties. As a functional component of the CS-1 formulation, salmon bone-derived ingredients showed activity in the comparative pharmacodynamic evaluation, suggesting that they may contribute to the overall bone-protective effect. Conclusions: Different calcium formulations showed distinct profiles in dissolution behavior, calcium retention, and bone-protective effects. Among the tested samples, CS-1 demonstrated relatively favorable overall performance, which may be related to its liquid dosage form and salmon bone-derived functional components. Full article

Understanding mass transport of structurally different drugs within ionically crosslinked hydrogel networks remains an important challenge in polymer-based delivery systems. In this study, hydrophilic amoxicillin (AMOX) and amphiphilic doxycycline (DOX) were encapsulated into calcium–alginate beads, respectively. A three-factor and three-level Box–Behnken design was utilized to examine the influences of alginate concentration (2–5%, w/v), CaCl₂ concentration (1–3%, w/v), and gelation time (15–45 min) on encapsulation efficiency (EE). EE exhibited considerable variability for both AMOX (10–86%) and DOX (10–63%). Optimal EE values were achieved at almost 3.5% alginate and 3% CaCl₂. The optimized gelation times differed between AMOX (45 min) and DOX (15 min), which is likely associated with differences in their physicochemical properties, although additional intermediate gelation times could further refine the optimal conditions. ANOVA identified CaCl₂ concentration and the quadratic effect of alginate as the most influential parameters. Furthermore, both models demonstrated robust predictive capability (R² > 0.98). In vitro release experiments demonstrated minimal drug diffusion in simulated gastric fluid (SGF) and significantly accelerated release in simulated intestinal fluid (SIF). These findings indicate a pH-responsive release behavior under simulated gastrointestinal conditions. The release profile was best represented by Higuchi and Korsmeyer–Peppas kinetic models. SEM and optical microscopy revealed uniform spherical beads with drug-dependent microstructural differences: hydrophilic AMOX produced smoother, wrinkled surfaces, whereas amphiphilic DOX induced localized cracking and heterogeneous microdomains. Furthermore, DLS and zeta potential measurements of the released fractions indicated nanoscale particle populations (≈190–225 nm) with moderate negative surface charge (≈−21 mV), suggesting stable colloidal dispersion during intestinal-phase release. Full article

Saccharomyces cerevisiae FOSU-QQT (SC.QQT), isolated from pineapple pomace wine, exhibits favorable aroma-producing capabilities. In this study, we performed integrated genomic and phenotypic analyses to comprehensively evaluate its safety profile, probiotic potential, and aroma-producing characteristics. Whole-genome sequencing (WGS) assembly predicted a genome size of 30,256,254 bp, encompassing 12,899 genes with a total coding length of 22,062,659 bp and an average GC content of 37.30%. Preliminary safety assessments, including hemolysis tests, antibiotic susceptibility profiling, and antibacterial activity assays, were complemented by in silico screening for antibiotic resistance-associated genes. Functional tolerance assays, specifically resistance to simulated gastrointestinal fluid, acid stress, and bile salts, demonstrated that SC.QQT exhibited robust survival under physiologically relevant gastrointestinal conditions. Collectively, these findings support its potential as a promising probiotic candidate with notable resilience, although further in vivo validation is required to confirm its application value. Additionally, gas chromatography–mass spectrometry (GC–MS) analysis of volatile compounds in pineapple pomace wine indicated that the presence of aroma-related genes in SC.QQT may enhance overall flavor complexity and intensify fruity aromatic notes during fermentation, underscoring its distinctive utility in fruit wine bioprocessing. Full article

In ulcerative colitis (UC), the therapeutic efficacy of nanoparticle (NP)-based drug delivery systems is limited by premature drug release, uptake or degradation of NPs during their passage through the harsh gastrointestinal tract (GIT) environment, poor colon targeting, and rapid NP clearance caused by diarrhea symptoms. This study focused on designing an advanced spatiotemporally controlled nanohybrid hydrogel drug delivery system to overcome these challenges. We developed a pH- and temperature-responsive polysaccharide-based hydrogel composed of chitosan (CS), β-glycerol phosphate disodium salt pentahydrate (GP), hydroxypropyl cellulose (HPC), and collagen type I (Col I), designated as CS/HHPC/Col I-GP. The hydrogel exhibited a dense and uniform porous reticular structure, with an average pore diameter of 127.45 ± 2.22 μm. The equilibrium swelling ratio of the CS/HHPC/Col I-GP was determined to be 32.10 ± 1.11 g/g, indicating excellent swelling capacity and sustained structural stability over 6 h—making it suitable for sustained drug release in the intestinal tract. Then, the prepared curcumin nanoparticles (CurNPs) were encapsulated into the CS/HHPC/Col I-GP hydrogel to form the CS/HHPC/Col I-GP-CurNPs composite. The polysaccharide-based hydrogel shell of the formulation withstood harsh gastrointestinal conditions, enabled targeted adhesion to the colon, and was specifically degraded by colonic enzymes. The CurNPs released in the colon benefit from their negatively charged characteristics, enabling accumulation at the positively charged inflamed sites and achieving sustained Cur release. The results of the gastrointestinal digestion simulation experiment showed that the cumulative release of CS/HHPC/Col I-GP-CurNPs was only 12.33 ± 2.17% in simulated gastric fluid (SGF) and reached 96.91 ± 1.98% in simulated colonic fluid (SCF) after 60 h. Cell and animal experimental data confirmed that the formulation significantly alleviated colitis symptoms by modulating the repolarization of pro-inflammatory M1 macrophages to anti-inflammatory M2 phenotypes and deactivating the TLR4/MyD88/NF-κB pathway. Furthermore, the integrity of the intestinal mucosal barrier and the gut microbiota were enhanced. This study provides a promising strategy for the oral drug treatment of UC. Full article

The use of lactic acid bacteria for the management of hyperuricemia has attracted growing interest, whereas the specific emphasis on cold-adapted uric acid-degrading probiotics in the fermentation of traditional foods remains underexplored. In this study, Lacticaseibacillus paracasei NEFU-6 was isolated from Northeastern Chinese Kimchi and efficiently degraded uric acid (UA) at a temperature relevant to food fermentation (15 °C) and under simulated physiological conditions (37 °C). The results showed that strain NEFU-6 degraded 25.48% of UA in 6 days at 15 °C, and 40.55% after 72 h at 37 °C in 0.84 g/L of uric acid. All probiotic and safety-related properties were evaluated at 37 °C to simulate human physiological conditions. In vitro probiotic characterization revealed that strain NEFU-6 exhibits non-hemolytic activity, strong free radical-scavenging capacity, significant surface hydrophobicity, and an auto-aggregation rate of 52.65% after 24 h. The strain NEFU-6 also demonstrated robust survival under simulated gastrointestinal conditions, with tolerance rates of 70.7% in 0.3% bile salts, 51.02% in gastric juice at pH 1.5, and 62.61% after 4 h of exposure to artificial intestinal fluid, indicating strong adaptability. Furthermore, the application of strain NEFU-6 in kimchi fermentation improved product quality, confirming its potential for the development of low-temperature functional foods. Full article

This study isolated and characterized Lactiplantibacillus plantarum WYP from naturally fermented pineapple peel residues. The strain exhibited a potent in vitro histamine degradation rate of 78.63% and demonstrated multiple probiotic properties, including acid and bile salt tolerance, simulated gastrointestinal fluid resistance, antimicrobial activity against foodborne pathogens, and in vitro cholesterol-lowering ability. Whole-genome sequencing revealed a 3.34 Mb circular genome encoding 3200 genes. Genomic analysis elucidated a multidimensional “Prevention–Promotion–Utilization” (PPU) strategy for histamine regulation: prevention via the absence of histidine decarboxylase (hdc) genes; promotion of degradation via multicopper oxidase (e.g., cueO) and amine oxidase systems; and utilization through downstream aldehyde metabolism and redox homeostasis genes. Safety assessments confirmed the strain’s non-hemolytic nature, absence of harmful metabolite production, and no detectable risk of acquired antibiotic resistance gene transfer. The integration of phenotypic and genomic evidence positions LPWYP as a promising probiotic candidate for mitigating biogenic amines in fermented foods. Full article

Background: Functional dyspepsia (FD) is a disorder of gut–brain interaction characterized by heterogeneous pathophysiological mechanisms, including altered gastric motility, visceral hypersensitivity, low-grade inflammation, impaired mucosal defence, and oxidative stress. Multi-target botanical strategies may represent a rational approach for addressing this complexity. Methods: This study evaluated the mechanistic rationale supporting a botanical formulation containing Zingiber officinale, Cynara scolymus, and Citrus limon extracts, here referred to as DyspepCyn^®. A focused narrative review was conducted to summarize the available mechanistic and clinical evidence for the three botanicals. In addition, the formulation was characterized through solubility testing in aqueous and biorelevant simulated gastrointestinal media, together with antioxidant assessment using ORAC and DPPH assays. Results: DyspepCyn^® showed favourable dispersion and solubility behaviour across simulated gastrointestinal conditions, with complete solubilization up to approximately 700 mg/100 mL in water and up to approximately 800 mg/100 mL in simulated intestinal fluids. No precipitation was observed in the tested media. The formulation also showed measurable antioxidant activity, with an ORAC value of 365 µmol Trolox equivalents/g and a DPPH radical scavenging EC₅₀ of 32 µg/mL. Conclusions: DyspepCyn^® combines botanicals with complementary actions on gastric motility, postprandial digestive processes, mucosal protection, and oxidative stress. The observed physicochemical stability and antioxidant capacity support the mechanistic rationale for this multi-target botanical strategy in FD. Clinical studies are required to confirm its efficacy in patients with FD. Full article

Poor solubility and low permeability remain major obstacles to the oral bioavailability of mesalazine (5-aminosalicylic acid, 5-ASA), a BCS Class IV anti-inflammatory drug used in the treatment of inflammatory bowel diseases. In this study, we report a novel eutectogel (EG) platform based on a natural deep eutectic solvent (NADES) composed of choline chloride and lactic acid (ChCl:LA, 1:10 molar ratio). The NADES significantly enhanced mesalazine solubility, reaching 35 mg/mL, nearly 40-fold higher than in water. The drug-loaded NADES was structured using hydroxyethyl cellulose and Carbomer 140 to obtain a gel matrix, which was subsequently coated with Eudragit^® S100 to provide pH-dependent release and gastro-resistance. Physicochemical characterization was carried out via FT-IR and NMR spectroscopy, polarized optical microscopy (POM), and swelling studies in simulated fluids. In vitro release studies under simulated gastrointestinal conditions revealed minimal drug release at gastric pH (1.2) and a sustained release (>80%) at colonic pH (7.4) over 48 h. These results support the potential of ChCl:LA-based eutectogels as a biocompatible, green, and effective delivery system for the site-specific release of poorly soluble drugs in the colon. Full article

Bioactive food ingredients offer significant health benefits. However, their poor water solubility and storage stability often limit their efficacy and practical application. In this study, quinoa peptide nanoparticles (QPNPs) were fabricated by controlled enzymatic hydrolysis, with particle sizes below 100 nm. Their structural stability was primarily maintained through hydrophobic interactions and hydrogen bonding. Caffeic acid phenethyl ester (CAPE) was selected as a model compound to evaluate the encapsulation performance of QPNPs. The results demonstrated that the encapsulation of CAPE was mainly driven by hydrophobic interactions and hydrogen bonding. The CAPE-loaded QPNPs (CAPE-QPNPs) exhibited a uniform particle size (194.1 ± 1.2 nm), high encapsulation efficiency (77.2%), and loading capacity (3.9%), significantly improving the water solubility and storage stability of CAPE. Furthermore, the cumulative release of CAPE in simulated gastrointestinal fluid was only 34% after 4 h, indicating strong resistance to digestion, which may be attributed to the dense shell structure of the nanoparticles. Overall, these findings suggest that QPNPs are a promising delivery system for encapsulating bioactive food ingredients and enhancing their physicochemical stability. Full article

Mealworm (Tenebrio molitor) is considered a sustainable protein source and classified as a non-novel food by Health Canada. However, data on safe consumption levels based on bioaccessible metal(loid) concentrations are limited. In this study, a modified continuous on-line leaching method (COLM) coupled with inductively coupled plasma mass spectrometry (ICPMS) was developed to quantify bioaccessible Cr, As, Se, and Cd in mealworm powder. Samples were packed into a transparent polypropylene flash column and sequentially leached with artificial saliva and gastric juice at 37 °C to simulate gastrointestinal digestion, with continuous monitoring of released elements by ICPMS. The proposed method required approximately 70 min per sample as opposed to over 2 h with conventional batch methods. Whereas the bioaccessible concentration of Se was negligible, 13 ± 5 µg/kg Cr, 18 ± 5 µg/kg As and 18 ± 6 µg/kg Cd were released, representing 14%, 15%, and 26% of their total concentration, respectively. Mass balance was verified for Cr, As, Se, and Cd, demonstrating the reliability of the method. Additionally, different sources of elements were revealed by plotting the temporal profile of one element versus that of another element for each gastro-intestinal fluid. A preliminary quantitative risk assessment indicated that adults can safely consume 105 g mealworm per day. Although no significant noncarcinogenic risk was identified, the incremental lifetime cancer risk of 5.2 × 10⁻⁶ for As and 1 × 10⁻⁶ for Cr exceeds or equals the Ontario threshold, indicating potential concern. This study is the first to apply the COLM to mealworm while integrating bioaccessibility data for a more realistic risk assessment. However, back-pressure issues result in a relative standard deviation up to 39%. Full article

Chlorogenic acid (CGA) is a natural polyphenol with various biological activities, but its poor stability and premature release in the gastrointestinal tract limit oral application. Herein, a pH-responsive bilayer hydrogel based on sodium alginate (SA) and carboxymethyl cellulose (CMC) was developed to enhance the gastrointestinal stability and controlled release of CGA. CGA-loaded SA hydrogels were prepared via Ca²⁺-induced ionotropic gelation, followed by CMC coating to form a bilayer structure. The SA/CMC hydrogels showed a drug loading capacity of 15.2–16.7% and pH-dependent swelling behavior. In vitro release studies revealed that the bilayer hydrogel suppressed CGA release in simulated gastric fluid (pH 1.2), with a cumulative release of approximately 30%, while enabling sustained release in simulated intestinal fluid (pH 6.8), reaching about 70% within 10 h. Release kinetics indicated that CGA release was controlled by Fickian diffusion under acidic conditions and by a diffusion-polymer relaxation mechanism under intestinal conditions. Moreover, encapsulation in the SA/CMC hydrogel improved the thermal, light, and pH stability of CGA while maintaining its antioxidant activity and biocompatibility. These results indicate that SA/CMC bilayer hydrogels provide a promising strategy for stabilized gastrointestinal delivery of chlorogenic acid. Full article