In vivo determination of the bioavailability of folic acid through the utilization of the PBPK model in conjunction with UPLC.

This paper employed a physiologically based pharmacokinetic model (PBPK) to investigate the transformations of folic acid and its metabolites in vivo. Additionally, an ultra-performance liquid chromatography (UPLC) method was developed to accurately measure the body's retention rate and conversion rate of folic acid, tetrahydrofolate, and 5-methyltetrahydrofolate. Furthermore, the bioavailability of folic acid in the body was assessed by combining this method with an evaluation technique for animal models. The study found that the gastric metabolism time was 2 h, while the small intestinal metabolism duration was 4 h. The maximum conversion rate was observed in plasma and liver after 6 h, and in the brain after 8 h. This serves as a framework for creating a model to assess the bioavailability of folic acid in living organisms, to enhance the safety and efficacy of folic acid intake.

Dynamic water migration and flavor analysis of sea cucumber in the process of Sichuan pepper seasoning soak.

Soaking in seasoning solution is the main process of sea cucumber seasoning. This study analyzed the dynamic changes in water migration and flavor substances in sea cucumbers during soaking in a Sichuan pepper solution. It was found that the sea cucumber experienced a process of water absorption followed by water loss during the 0-48 h soaking process. During this period, the flavor compounds in sea cucumbers showed different dynamic trends. A total of 46 volatiles were identified, of which 29 were key flavor compounds. Its flavor profiles tended to stabilize as soaking time increased. m-Xylene, d-Limonene, Eucalyptol, p-Xylene, Sabinene, Beta-Myrcene, and Beta-Phellandrene were the main characteristic substances contributing to the differences in sea cucumber flavor. Correlation analysis predicted the relationship between water migration and the dynamic shifts in flavor compounds. This study provides a crucial reference for future studies on the processing and flavor modulation of sea cucumber products.

Evaluation of the texture characteristics and taste of shrimp surimi with partial replacement of NaCl by non­sodium metal salts.

Ionic strength plays a significant role in the aggregation behavior of myofibrillar proteins. The study investigated the effects of KCl or CaCl2 as substitutes for NaCl on the gel properties and taste of shrimp surimi at a constant ionic strength (IS = 0.51). Increased KCl substitution ratio resulted in a reduction in α-helix content and an increase in ß-sheet content of myofibrillar proteins, thereby enhancing water holding capacity. Optimal KCl substitutions (1.5% NaCl +1.94% KCl) contributed to maintaining the desired taste and improving gel properties. CaCl2 facilitates the extraction and dissolution of myofibrillar proteins, resulting in an organized and dense gel network with significant water-holding capacity. However, excessive additions (>1.27%) resulted in a notable decrease in taste and gel strength due to excessive aggregation and precipitation of myofibrillar proteins. These findings provide a solid theoretical foundation for production of high-quality, low-salt shrimp surimi.

Different stages of flavor variations among canned Antarctic krill (Euphausia superba): Based on GC-IMS and PLS-DA.

The aim of the present study was to explore changes in the profile of volatile compounds (VCs) in canned Antarctic krill (Euphausia superba) at different processing stages using partial least squares discriminant analysis (PLS-DA) and gas chromatography-mass spectrometry (GC-IMS). A total of 43 VCs were detected using GC-IMS in all krill meat samples, which included mainly alcohols, aldehydes, ketones, esters, and furans. Considering the different processing stages, the highest variation in VCs and the highest VC content were observed in krill meat which underwent both blanching and salt addition. PLS-DA further revealed flavor differences in canned Antarctic krill meat at different processing stages, with octanal, 2-hexanol, 2-octane, 2,3,5-trimethyl pyrazine, and cis-3-hexanol as the main contributors to observed differences in VC profiles. These findings contribute to the production of high-quality canned krill meat, enhancing its flavor quality and providing a feasible theoretical basis for future krill meat pretreatment and industry development.

Investigation into Potential Allergenicity and Digestion-Resistant Linear Epitopes of Fish Skin Gelatin in Cell-Cultured Meat Scaffolds.

As a key component of cell-cultured fish, fish skin gelatin (FSG)-based cell scaffold provides support structures for cell growth, proliferation, and differentiation. However, there are potential allergenicity risks contained in FSG-based scaffolds. In this study, 3D edible scaffolds were prepared by phase separation method and showed a contact angle of less than 90°, which indicated that the scaffolds were favorable for cell adhesion. Besides, the swelling ratio was greater than 200%, implying a great potential to support cell growth. The sequence homology analysis indicated that FSG was prone to cross-reaction with collagen analogues. Additionally, a food allergic model was constructed and represented that mice gavaged with cod FSG exhibited higher levels of specific antibodies, mast cell degranulation, vascular permeability, and intestinal barrier impairment than those gavaged with pangasius and tilapias FSG. Its higher allergenicity might be attributed to a higher number of digestion-resistant linear epitopes. Moreover, the higher hydrolysis degree linked to the exposure of linear epitopes to promote the combination with IgE, which was also responsible for maintaining the higher allergenicity of cod FSG. This study clarifies allergenic risks in cell-cultured fish and further study will focus on the allergenicity reduction of FSG-based cell scaffolds.

Characterization and in vitro calcium release of the novel calcium-loaded complexes using Antarctic krill protein and pectin: Effect of different blending sequences.

Food-grade biopolymer-based complexes are of particular interest in the field of biologic ingredient delivery owing to unique controlled-release properties. Herein, three calcium-loaded complexes using Antarctic krill protein (P) and pectin (HMP) with different blending sequences were designed, named P + Ca + HMP, P + HMP + Ca and HMP + Ca + P, respectively. The calcium-loaded capacity, structural properties, and in vitro gastrointestinal calcium release of the complexes were investigated. The results demonstrated that the calcium binding rate and content of the P + Ca + HMP complex were the highest, reaching to 90.3 % and 39.0 mg/g, respectively. Particularly, the P + Ca + HMP complex exhibited a more stable fruit tree-like structure. Furthermore, the structural analysis confirmed that the primary interaction forces involved hydrogen bond, electrostatic, hydrophobic and ionic bond interaction. Ultimately, the P + Ca + HMP complex demonstrated superior calcium delivery. In conclusion, a novel calcium delivery system was successfully developed based on optimized the self-assembly sequence, which held significant importance in promoting the high-value utilization of Antarctic krill protein and enhancing the in vitro bioaccessibility of calcium.

Study on the adsorption and migration rule of Sichuan pepper characteristic volatile compounds during the cooking process in the sea cucumber body wall.

The natural flavor of sea cucumber is generally not easily accepted by consumers. In this study, the effect of different cooking conditions on the adsorption of the characteristic flavor of Sichuan pepper by sea cucumber was investigated by response surface methodology, and the optimal cooking conditions were identified. A total of 45 volatiles were identified based on gas chromatography-mass spectrometry, of which 27 were key flavor actives. Low-field nuclear magnetic resonance and textural analysis showed that the addition of Sichuan pepper during the cooking process affected the water migration and the textural properties of sea cucumbers. It was shown that the addition of Sichuan pepper could significantly improve the flavor and other quality characteristics of sea cucumber. This study has important practical guiding significance for the flavor improvement and product innovation of sea cucumber food.

The neuroprotective effects of SFGDI on sirtuin 3-related oxidative stress by regulating the Sirt3/SOD/ROS pathway and energy metabolism in BV2 cells.

Recently, the investigation of neuroprotective peptides has gained attention in addressing memory impairment and cognitive decline. Although the potential neuroprotective peptide Serine-Phenylalanine-Glycine-Aspartic acid-Isoleucine (SFGDI) has been identified from sea cucumber, the molecular mechanisms remain unclear. This study was conducted to explore the neuroprotection of SFGDI against 3-TYP-induced oxidative stress in BV2 cells. The results showed a retention rate of 76.70% during in vitro simulated gastrointestinal digestion and an absorption rate of 10.41% in a rat-everted gut sac model for SFGDI. Two hours following the administration of SFGDI via gavage in mice, a notable fluorescence was observed in the brain, indicating a potential neuroprotection of SFGDI through its interactions with nerve cells. By utilizing a model of oxidative stress injury induced by 3-TYP in BV2 cells, it was determined that pretreatment with SFGDI (50-200 µg mL-1) resulted in a dose-dependent reduction in the acetylated SOD level, leading to enhanced SOD activity and reduced levels of ROS and MDA. In addition, this pretreatment triggered an increase in unsaturated lipid levels, which helped maintain the intracellular lipid metabolism balance and preserve the mitochondrial function and glycolysis levels to regulate energy metabolism. The results of this study indicate that SFGDI demonstrates neuroprotective properties through its modulation of the Sirt3/SOD/ROS pathway, regulation of lipid metabolism, and enhancement of energy metabolism in BV2 cells. These findings suggest potential novel therapeutic approaches for addressing Sirt3-related memory deficits and neurodegenerative disorders.

Polysaccharide-Based Micro/Nanomotors for Active Ingredient Delivery in Food.

Micro/nanomotors (MNMs) are miniature devices that can generate energy through chemical reactions or physical processes, utilizing this energy for movement. By virtue of their small size, self-propulsion, precise positioning within a small range, and ability to access microenvironments, MNMs have been applied in various fields including sensing, biomedical applications, and pollutant adsorption. However, the development of food-grade MNMs and their application in food delivery systems have been scarcely reported. Currently, there are various issues with the decomposition, oxidation, or inability to maintain the activity of some nutrients or bioactive substances, such as the limited application of curcumin (Cur) in food. Compared to traditional delivery systems, MNMs can adjust the transport speed and direction as needed, effectively protecting bioactive substances during delivery and achieving efficient transportation. Therefore, this study utilizes polysaccharides as the substrate, employing a simple, rapid, and pollution-free template method to prepare polysaccharide-based microtubes (PMTs) and polysaccharide-based micro/nanomotors (PMNMs). PMNMs can achieve multifunctional propulsion by modifying ferrosoferric oxide (Fe3O4), platinum (Pt), and glucose oxidase (GOx). Fe-PMNMs and Pt-PMNMs exhibit excellent photothermal conversion performance, showing promise for applications in photothermal therapy. Moreover, PMNMs can effectively deliver curcumin, achieving the effective delivery of nutrients and exerting the anti-inflammatory performance of the system.

A Novel Tetrapeptide Ala-Phe-Phe-Pro (AFFP) Derived from Antarctic Krill Prevents Scopolamine-Induced Memory Disorder by Balancing Lipid Metabolism of Mice Hippocampus.

Memory impairment is a serious problem with organismal aging and increased social pressure. The tetrapeptide Ala-Phe-Phe-Pro (AFFP) is a synthetic analogue of Antarctic krill derived from the memory-improving Antarctic krill peptide Ser-Ser-Asp-Ala-Phe-Phe-Pro-Phe-Arg (SSDAFFPFR) after digestion and absorption. The objective of this research was to assess the neuroprotective effects of AFFP by reducing oxidative stress and controlling lipid metabolism in the brains of mice with memory impairment caused by scopolamine. The 1H Nuclear magnetic resonance spectroscopy results showed that AFFP had three active hydrogen sites that could contribute to its antioxidant properties. The findings from in vivo tests demonstrated that AFFP greatly enhanced the mice's behavioral performance in the passive avoidance, novel object recognition, and eight-arm maze experiments. AFFP reduced oxidative stress by enhancing superoxide dismutase activity and malondialdehyde levels in mice serum, thereby decreasing reactive oxygen species level in the mice hippocampus. In addition, AFFP increased the unsaturated lipid content to balance the unsaturated lipid level against the neurotoxicity of the mice hippocampus. Our findings suggest that AFFP emerges as a potential dietary intervention for the prevention of memory impairment disorders.

Digestive and Absorptive Properties of the Antarctic Krill Tripeptide Phe-Pro-Phe (FPF) and Its Auxiliary Memory-Enhancing Effect.

Aging and stress have contributed to the development of memory disorders. Phe-Pro-Phe (FPF) was identified with high stability by mass spectrometry from simulated gastrointestinal digestion and everted gut sac products of the Antarctic krill peptide Ser-Ser-Asp-Ala-Phe-Phe-Pro-Phe-Arg (SSDAFFPFR) which was found to have a positive impact on memory enhancement. This study investigated the digestive stability, absorption, and memory-enhancing effects of FPF using nuclear magnetic resonance spectroscopy, simulated gastrointestinal digestion, in vivo fluorescence distribution analysis, mouse behavioral experiments, acetylcholine function, Nissl staining, immunofluorescence, and immunohistochemistry. FPF crossed the blood-brain barrier into the brain after digestion, significantly reduced shock time, working memory errors, and reference memory errors, and increased the recognition index. Additionally, FPF elevated ACh content; Nissl body counts; and CREB, SYN, and PSD-95 expression levels, while reducing AChE activity (P < 0.05). This implies that FPF prevents scopolamine-induced memory impairment and provides a basis for future research on memory disorders.

Conformation-Activity Mechanism of Alcalase Hydrolysis for Reducing In Vitro Allergenicity of Instant Soy Milk Powder.

Effective reduction of the allergenicity of instant soy milk powder (ISMP) is practically valuable for expanding its applications. This study optimized the enzymolysis technology of ISMP using single-factor experiments and response surface methodology, combined serological analysis, cellular immunological models, bioinformatics tools, and multiple spectroscopy techniques to investigate the effects of alcalase hydrolysis on allergenicity, spatial conformation, and linear epitopes of ISMP. Under the optimal process, special IgE and IgG1 binding abilities and allergenic activity to induce cell degranulation of alcalase-hydrolyzed ISMP were reduced by (64.72 ± 1.76)%, (56.79 ± 3.72)%, and (73.3 ± 1.19)%, respectively (P < 0.05). Moreover, the spatial conformation of instant soy milk powder hydrolysates (ISMPH) changed, including decreased surface hydrophobicity, a weaker peak of amide II band, lower contents of α-helix and ß-sheet, and an enhanced content of random coil. Furthermore, the linear epitopes of major soy allergens, 9 from glycinin and 13 from ß-conglycinin, could be directionally disrupted by alcalase hydrolysis. Overall, the structure-activity mechanism of alcalase hydrolysis to reduce ISMP allergenicity in vitro was preliminarily clarified. It provided a new research direction for the breakthrough in the desensitization of ISMP and a theoretical basis for revealing the potential mechanism of alcalase enzymolysis to reduce the allergenicity of ISMP.

Effects of different thermal sterilization conditions on the quality of ready-to-eat shrimp based on specific sterilization intensity.

The effects of different thermal sterilization conditions on the quality and digestibility of ready-to-eat (RTE) shrimp were investigated. Compared with the high-temperature (121 °C) and short-time (6 min and 8 min) sterilization, the low-temperature (110 and 115 °C) and long-time (>20 min) sterilization significantly promoted the Maillard and browning reactions and changed the color of the RTE-shrimp. The high sterilization temperature promoted shrimp protein oxidation, resulting in increased carbonyl group, disulfide bond, and free radical content, while the free sulfhydryl group content decreased. This oxidation and tissue destruction at high temperature led to reduced texture properties and altered water distribution within the shrimp's muscles. However, sterilized shrimp exhibited superior digestive properties in an in vitro simulated digestion experiment. High-temperature and short-time sterilization is more effective in mitigating the quality deterioration of RTE-shrimp compared to low-temperature and long-time sterilization.

Molecular Mechanisms of Iron Transport and Homeostasis Regulated by Antarctic Krill-Derived Heptapeptide-Iron Complex.

In this study, the molecular mechanisms of iron transport and homeostasis regulated by the Antarctic krill-derived heptapeptide-iron (LVDDHFL-iron) complex were explored. LVDDHFL-iron significantly increased the hemoglobin, serum iron, total iron binding capacity levels, and iron contents in the liver and spleen to normal levels, regulated the gene expressions of iron homeostasis, and enhanced in vivo antioxidant capacity in iron-deficiency anemia mice (P < 0.05). The results revealed that iron ions within LVDDHFL-iron can be transported via the heme transporter and divalent metal transporter-1, and the absorption of LVDDHFL-iron involved receptor-mediated endocytosis. We also found that the transport of LVDDHFL-iron across cells via phagocytosis was facilitated by the up-regulation of the high mobility group protein, heat shock protein ß, and V-type proton ATPase subunit, accompanied by the regulatory mechanism of autophagy. These findings provided deeper understandings of the mechanism of LVDDHFL-iron facilitating iron absorption.

Impact of Corn Starch Molecular Structures on Texture, Water Dynamics, Microstructure, and Protein Structure in Silver Carp (Hypophthalmichthys molitrix) Surimi Gel.

This study systematically investigates the impact of corn starch molecular structures on the quality attributes of surimi gel products. Employing molecular analyses to characterize corn starch, three amylopectin fractions (A, B1, and B2), categorized by the degree of polymerization ranges (6 < X ≤ 12, 12 < X ≤ 24, and 24 < X ≤ 36, respectively) were specifically focused on. The surimi gel quality was comprehensively assessed through texture profile analysis, nuclear magnetic resonance, scanning electron microscopy, stained section analysis, and Fourier transform infrared spectroscopy. Results indicated the substantial volume expansion of corn amylopectin upon water absorption, effectively occupying the surimi gel matrix and fostering the development of a more densely packed protein network. Starch gels with higher proportions of A, B1, and B2 exhibited improved hardness, chewiness, and bound water content in the resultant surimi gels. The weight-average molecular weight and peak molecular weight of corn starch showed a strong positive correlation with surimi gel hardness and chewiness. Notably, the secondary structure of proteins within the surimi gel was found to be independent of corn starch's molecular structure. This study provides valuable insights for optimizing formulations in surimi gel products, emphasizing the significance of elevated A, B1, and B2 content in corn starch as an optimal choice for crafting dense, chewy, water-retaining surimi gels.

Regulation mechanisms of sea cucumber peptides against scopolamine-induced memory disorder and novel memory-improving peptides identification.

Memory impairment affects cognition and information processing, and attention, leading to a decline in life quality of patients. Previous studies have shown the memory-improving effects of sea cucumber peptides. This study further explored the memory-improving mechanisms of sea cucumber peptides using scopolamine-induced memory-impaired mice and identified novel memory-improving peptides within low molecular weight peptide fractions. The sea cucumber peptides were categorized into three groups based on their molecular weights: SCP-L (molecular weight greater than 10 kDa), SCP-M (weight between 3 kDa and 10 kDa), and SCP-S (molecular weight less than 3 kDa). The results showed that SCP-S improved behavioral performance by regulating cholinergic system disorder and reducing oxidative stress levels, distinguishing itself from SCP-M and SCP-L. Further, SCP-S was found to exhibit a well ability in alleviating the degree of neuroinflammation dependent on microglia and promoting synaptic plasticity. Additionally, a novel memory-improving peptide Ser-Phe-Gly-Asp-Ile (SFGDI) was identified by EASY-nano-LC/MS/MS after simulated digestion-absorption coupling of in silico technologies from SCP-S. SFGDI protected against oxidative stress and regulated cholinergic system in scopolamine-induced PC12 cells. These findings suggest that SCP-S and SFGDI might be considered as potential memory-improving food for people suffering from memory disorders.

The improvement effects of Lentinus edodes powder marination on sous vide cooked chicken patties: Physicochemical attributes, oxidative properties and flavor characteristics.

The improvement effects of Lentinus edodes powder (LEP) marination with different concentrations (0, 6-14 %) on physicochemical, oxidative and flavor quality of chicken patties were evaluated. Greater pH, redness, yellowness, water holding capacity and their strong correlations were observed in LEP-marinated samples. Changed water distribution, inhibited lipid oxidation and enhanced protein oxidation occurred through LEP marination. The highest gel strength and resilience and the lowest hardness and chewiness were obtained in 10 % LEP-marinated sample. Meanwhile, taste activity values of amino acids and saltiness peaked and umami rose in this sample. 124 volatiles were detected and 16 compounds were simultaneously detected by gas chromatography-ion mobility spectrometry and gas chromatography-mass spectrometry. Hexanal, 1,2,4-trithiolane and 1-hexanol were considered as the key differential aroma-active compounds according to odor activity values and chemometric analysis. This study confirmed LEP as a prospective ingredient to improve the quality of meat products.

Effects of quercetin and l-ascorbic acid on heterocyclic amines and advanced glycation end products production in roasted eel and lipid-mediated inhibition mechanism analysis.

Eel is a commercially important marine fish, frequently featured as sushi or roasted preparations. This study determined the formation of heterocyclic amines (HAs) and advanced glycation end products (AGEs) in roasted eel and evaluated the inhibitory mechanism of quercetin and l-ascorbic acid on their formation. The results indicate a respective reduction of 75.07% and 84.72% in total HAs, alongside a decline of 23.03% and 39.14% in AGEs. Additionally, fundamental parameters of roasted eel, lipid oxidation indicators and precursors were measured to elucidate the mechanisms and impact of natural antioxidants on HAs and AGEs formation in roasted eel. Furthermore, endeavors were made to probe into the molecular mechanisms governing the influence of key differential lipids on the generation of HAs and AGEs through lipid-mics analysis. This research emphasizes the potential of natural antioxidants in preventing harmful substances formation during eel thermal processing, which is helpful to food manufacturers for healthier food production.

Evaluation of In Vivo Folic Acid Bioavailability in Different Mouse Strains Using Enzymatic Digestion Combined with Ultra Performance Liquid Chromatography.

By analyzing the folic acid content of various mouse strains through the use of in vivo studies, this study sought to determine whether folic acid bioavailability varies between hosts. In order to examine the stability of folic acid in the gastrointestinal tract, the rate at which it enters the blood, its retention in the organs, and its entry into the brain, folic acid was gavaged for 10 days into male and female mice of the following four strains: C57BL/6, BALB/c, ICR, and Kunming. Folic acid was extracted from eight groups of mice via solid phase extraction and triple enzyme extraction; the folic acid was subsequently quantified by ultraperformance liquid chromatography. In contrast to the other groups, female C57BL/6 mice exhibited substantially greater bioavailability as well as variations in organ retention and blood entry rates, as indicated by the experimental findings. This finding indicated that using female C57BL/6 mice to evaluate the bioavailability of folic acid is more effective.

Regulation of ovalbumin allergenicity and structure-activity relationship analysis based on pulsed electric field technology.

The study focused on the regulation of ovalbumin (OVA) allergenicity using pulsed electric field (PEF) technology and examined the structure-activity link. Following PEF treatment, the ability of OVA to bind to IgE and IgG1 at 6 kHz was inhibited by 30.41 %. According to the microstructure, PEF caused cracks on the OVA surface. Spectral analysis revealed a blue shift in the amide I band and a decrease in α-helix and ß-sheet content indicating that the structure of OVA was unfolded. The disulfide bond conformation was transformed and the structure tended to be disordered. The increased fluorescence intensity indicated that tryptophan and tyrosine were exposed which led an increase in hydrophobicity. In addition, the results of molecular dynamics (MD) simulations confirmed that the stability of OVA was reduced after PEF, which was related to the reduction of hydrogen bonding and the sharp fluctuation of aspartic acid. Therefore, PEF treatment induced the exposure of hydrophobic amino acids and the transformation of disulfide bond configuration which in turn masked or destroyed allergenic epitopes, and ultimately inhibited OVA allergenicity. This study provided insightful information for the production of hypoallergenic eggs and promoted the use of PEF techniques in the food field.