Jingna Wu

The protective effects of Lactobacillus murinus on chemotherapy-related intestinal injury and immune imbalances were explored by establishing a cyclophosphamide (CTX)-induced mouse model of immunosuppression. CTX treatment led to intestinal barrier destruction, exacerbated local inflammation, and significantly reduced short-chain fatty acid levels (especially butyrate), accompanied by systemic immune suppression. Lactobacillus murinus intervention, especially at medium and high doses, dose-dependently repaired the intestinal barrier, inhibited inflammatory responses, restored levels of metabolites such as butyrate, and systematically regulated splenic immune cell proportions, restoring the CD4⁺/CD8⁺ balance. Metabolomic analysis further revealed that, at different doses, this regulation affected distinct metabolic pathways: low doses enhanced glutathione and purine metabolism, medium doses restored folate and steroid hormone metabolism, and high doses promoted fatty acid β-oxidation and galactose metabolism, forming a multi-level metabolic protective network. This suggests that L. murinus can alleviate chemotherapy-induced intestinal mucositis and mitigate systemic immune suppression through a dual local anti-inflammatory and systemic immune-regulatory effect, with potential mechanisms related to butyrate-mediated regulation of the “metabolism–immune axis,” providing evidence for probiotic-assisted chemotherapy.

Laver ( Porphyra haitanensis ) is a nutritious seaweed. Desiccation affects its quality and flavor, but the molecular changes during drying are unclear. Here, the effects of hot air drying temperatures (60°C, 70°C, 80°C, 90°C, and 100°C) on rehydration performance, drying kinetics, microstructure, and the biological activity of laver were evaluated. The laver dried at 60°C exhibited a rehydration ratio of 350%–450%, and its aqueous extract demonstrated substantially higher antioxidant activities than at other temperatures, with DPPH radical scavenging activity of 74.79%, hydroxyl radical scavenging activity of 86.42 U/mL, and ferric reducing antioxidant power of 0.53 μmol·TE/kg. The most suitable temperature was 60°C. Lipidomic profiling of laver during drying at 60°C for different durations (0–5 h) was conducted using liquid chromatography–mass spectrometry; 4092 lipids, including glycolipids, glycerophospholipids, and glycerides, were identified. Most lipids increased substantially with prolonged drying time, whereas five characteristic lipids, including cardiolipin (23:0/22:6/16:1/22:2), sulfoquinovosyldiacylglycerol (16:0/18:2 and 16:0/20:3), digalactosyldiacylglycerol (16:0/18:2), and monogalactosyldiacylglycerol (16:0/16:0), showed notable changes. Distinct patterns in five characteristic lipids during drying were identified: the contents of the sulfolipid, sulfoquinovosyl diacylglycerol (16:0/18:2 and 16:0/20:3) increased continuously, likely released from disintegrating photosynthetic membranes. The galactolipids, monogalactosyldiacylglycerol (16:0/16:0), and digalactosyldiacylglycerol (16:0/18:2), core constituents of thylakoids, decreased substantially after 3 h, directly reflecting photosynthetic membrane degradation. Changes in cardiolipin (23:0/22:6/16:1/22:2) were also noted, implicating alterations in mitochondrial membrane integrity. Additionally, 65 volatile compounds, including (E,Z)‐2,6‐nonadienal, decanal, (E)‐2‐octenal, (2E,4E)‐deca‐2,4‐dienal, butylated hydroxytoluene, and 2,4‐di‐tert‐butylphenol, were detected. These compounds, contributing to the aromatic properties of laver, decreased with increased drying time. Drying temperature and duration substantially influenced the physicochemical properties, lipid profiles, and volatile flavor compounds of laver. The molecular changes during drying were elucidated to improve the nutritional qualities of dried laver products.

To develop highly nutritious Bangia fusco-purpurea (BFP) vegan sausages, we investigated the effects of BFP, gluten, and xanthan gum–konjac gum–carrageenan complex gel (CG) on the gel strength and sensory quality of the sausages. The formulation process was optimized through single-factor and orthogonal tests, whereas the gel formation mechanism of the key factors was explored. The orthogonal test results showed that the optimal addition levels of BFP, gluten, and CG were 5%, 56%, and 37%, respectively. Variance analysis revealed that both gluten and CG significantly affected gel strength (p < 0.05), with gluten notably influencing the overall sensory quality (p < 0.05). Texture profile analysis (TPA) and rheological properties demonstrated that as gluten (33–37%) and CG (52–56%) concentrations increased, the gel strength and elastic modulus exhibited concentration-dependent enhancement. Further analysis of the sulfhydryl content, disulfide bonds, surface hydrophobicity, and microstructure revealed that higher gluten content promoted intermolecular disulfide crosslinking and hydrophobic group exposure, whereas CG contributed to physical filling via hydrogen and ionic bonds, resulting in a uniform and dense gel network structure. The synergistic effects of gluten and CG enhanced the gel properties of BFP vegan sausages, providing a theoretical foundation for the development of high-quality plant protein-based meat alternatives.

Immunomodulation is the primary biological activity of polysaccharides. We have previously demonstrated that Bangia fusco-purpurea polysaccharide (BFP) can modulate the immune function of immunosuppressed mice and increase the abundance of Lactobacillus murinus. However, the underlying mechanisms remain unclear. In the present study, we aimed to elucidate the L. murinus-mediated immunomodulatory effect of BFP. Co-culture of L. murinus and BFP revealed that BFP promoted the proliferation of L. murinus at the concentrations of 0.5%–2%. We established a mouse L. murinus depletion model, in which L. murinus was administered via gavage. Treatment with L. murinus significantly increased macrophage phagocytosis and the levels of immune-related factors in mice, including interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ). These results suggested that L. murinus contributes to the immunomodulatory effect of BFP. Given the important role of macrophages in innate and adaptive immunity, we further confirmed that L. murinus can enhance immune function. Under lipopolysaccharide (LPS)-induced inflammatory conditions, L. murinus stimulated the elevation of IL-10 expression, consequently promoted macrophages polarization toward the anti-inflammatory M2 type, which in turn prevented the overactivation of the inflammatory response and reversed the LPS-induced inflammation. It also maintained the balance between pro- and anti-inflammatory responses, thus playing a role in regulating immune function. . Finally, transcriptomic sequencing and pathway validation revealed that L. murinus regulates IL-10 through the macrophage/mitogen-activated protein kinase/nuclear factor-κB signaling axis. Overall, these results suggest that the immunomodulatory mechanism of the BFP may involve L. murinus-induced regulation of IL-10 through the macrophage/mitogen-activated protein kinase/nuclear factor-κB signaling axis.

Marine organisms are rich in antioxidant peptides; however, extracting these peptides is time‐consuming, labor‐intensive, and costly, with sequence losses leading to uncertain results. This study aimed to identify abalone‐derived antioxidant peptides with strong Keap1 binding ability and validate their antioxidative activities using a cellular oxidative damage model. We constructed an abalone‐derived peptide library comprising 363 peptides using virtual enzymatic hydrolysis techniques. Of the 98 human Keap1 protein structures available in the protein data bank database, 2FLU was selected as the receptor. Using the CDOCKER module in Discovery Studio software, molecular docking was performed with the peptide library as ligands and 2FLU as the receptor, targeting the binding site at coordinates x : 5.000222, y : 7.103889 and z : 5.058000. Ten abalone‐derived peptides with the strongest inhibition against Keap1–Nrf2 interaction were identified. A 2,2′‐azobis (2‐methylpropionamidine) dihydrochloride (AAPH)‐induced oxidative damage model in human umbilical vein endothelial cells (HUVECs) was used to verify the molecular docking results and identified DEDEDEDK as the most active antioxidant peptide. DEDEDEDK interferes with Keap1–Nrf2 binding, significantly reducing reactive oxygen species levels in damaged cells, increasing superoxide dismutase and catalase activities, and elevated glutathione content, indicating its potential to mitigate AAPH‐induced oxidative damage in HUVECs.

Background: Melanin overproduction leads to pigmented skin diseases. Brown algae polyphenols, non-toxic secondary metabolites, exhibit potential bioactivities. Sargassum fusiforme, an edible seaweed, has been underexplored in the field of beauty despite its polyphenol richness. Methods: Polyphenols from S. fusiforme were extracted using macroporous resin (SFRP) and ethyl acetate (SFEP). Their antioxidant and anti-aging properties, tyrosinase inhibitory activities, and mechanisms were assessed. The melanogenesis inhibition effect and mechanism by SFRP was examined in B16F10 melanoma cells. Results: Both SFRP and SFEP demonstrated scavenging activities against DPPH, superoxide anion, and hydroxyl radicals. SFRP showed stronger anti-collagenase and anti-elastase effects. They dose-dependently inhibited mushroom tyrosinase, with IC50 values of 9.89 μg/mL for SFRP and 0.99 μg/mL for SFEP. SFRP reversibly inhibited tyrosinase, while SFEP showed irreversible inhibition. SFRP also suppressed melanin content and intracellular tyrosinase activity in B16F10 cells, downregulating the expression of microphthalmia-associated transcription factor, tyrosinase, and tyrosinase-related protein 1 and 2 expression through the PI3K/Akt and MAPK/ERK signal pathways. Conclusions: S. fusiforme polyphenols, especially SFRP, exhibit promising antioxidant, anti-aging, and melanogenesis inhibitory properties, highlighting their potential application as novel anti-melanogenic agents in cosmetics and the food industry.

Omega-3 fatty acids are in high demand due to their efficacy in treating hypertriglyceridemia and preventing cardiovascular diseases. However, the growth of the industry is hampered by low purity and insufficient productivity. This study aims to develop an efficient RP-MPLC purification method for omega-3 fatty acid ethyl esters with high purity and capacity. The results indicate that the AQ-C18 featuring polar end-capped silanol groups outperformed C18 and others in retention time and impurity separation. By injecting pure fish oil esters with a volume equivalent to a 1.25% bed volume on an AQ-C18 MPLC column using a binary isocratic methanol–water (90:10, v:v) mobile phase at 30 mL/min, optimal omega-3 fatty acid ethyl esters were obtained, with the notable purity of 90.34% and a recovery rate of 74.30%. The total content of EPA and DHA produced increased from 67.91% to 85.27%, meeting the acceptance criteria of no less than 84% set by the 2020 edition of the Pharmacopoeia of the People’s Republic of China. In contrast, RP-MPLC significantly enhanced the production efficiency per unit output compared to RP-HPLC. This study demonstrates a pioneering approach to producing omega-3 fatty acid ethyl esters with high purity and of greater quantity using AQ-C18 RP-MPLC, showing this method’s significant potential for use in industrial-scale manufacturing.