Inflammatory bowel disease (IBD) is characterized by oxidative stress imbalance and intestinal barrier disruption. Reducing excessive ROS has become a promising therapeutic strategy. Compared with conventional polyphenols, nanomaterials offer greater stability and bioavailability for ROS scavenging. Here, ellagic acid (EA) was converted into uniform nanoparticles (EAs) with reactive oxygen scavenging capacity through horseradish peroxidase (HRP)-mediated oxidative polymerization and subsequently encapsulated in the anti-gastric acid hydrogel F-DP to obtain the hybrid system F-DP@EAs. EAs reduced ROS, MDA, NO, IL-1β, and TNF-α levels in vitro, while increasing IL-4 and IL-10 expression, thus alleviating inflammation. Herein, F-DP@EAs prolonged intestinal retention time and exerted superior protective effects in the DSS-induced colitis model. Oral F-DP@EAs lowered DAI, preserved colon length, increased glutathione (GSH) and superoxide dismutase (SOD), decreased NO and MDA, restored zonula occludens-1 (ZO-1), and reduced mucosal lesions. These findings demonstrate that combining nanoparticle and hydrogel technologies markedly enhances the preventive and protective efficacy of EA, highlighting F-DP@EAs as a promising candidate for future IBD therapy.

Sea cucumbers Apostichopus japonicus will vomit their intestines during certain stimulations, and the collagen of the body wall will then be degraded. To define the effect of the sea cucumber intestine extracts on the body wall, the intestinal extracts and crude collagen fibers (CCF) of sea cucumber A. japonicus were prepared. According to the gelatin zymography, the type of endogenous enzymes in intestinal extracts were mainly serine endopeptidases with optimal activities at pH 9.0 and 40 °C. According to the rheology results, the viscosity of 3% CCF decreased from 32.7 Pa·s to 5.3 Pa·s by adding intestine extracts. The serine protease inhibitor phenylmethanesulfonyl fluoride inhibited the activity of intestinal extracts and increased the viscosity of collagen fibers to 25.7 Pa·s. The results proved that serine protease in the intestinal extracts participated in the process of body wall softening in sea cucumbers.

This study examined the effects of soy protein isolate (SPI) 7S and SPI 11S on the anthocyanin (AN) retention rate of Lonicera caerulea L. under different processing conditions and further analyzed the molecular interaction mechanisms between 7S/11S and cyanidin-3-O-glucoside (C3G). The results demonstrated that SPI increased the retention rate of anthocyanins to varying degrees while also enhancing the digestive stability. Multispectral results indicated that static quenching occurred between 7S/11S and C3G, and the polarity changes in the amino acid microenvironment varied with pH. Thermodynamic analysis indicated that hydrogen bonds dominated the interaction under both pH conditions, while a certain degree of hydrophobic interaction was additionally observed under neutral conditions. After binding with C3G, the proportion of β-sheet structures in SPI decreased and the proportion of other structures increased. Finally, molecular docking further simulated the binding between SPI and C3G and revealed the important roles of hydrophobic interactions and hydrogen bonding, which also promoted the combination of SPI and C3G to form a stable complex. This study provides a mechanistic reference for using proteins as effective carriers to protect anthocyanins, with implications for developing functional food components with enhanced stability.

In this study, amino-modified micro-mesoporous silica (NH₂-MMS) with hierarchical pores was prepared by modifying micro-mesoporous silica ZSM-5 with 3-aminopropyltriethoxysilane and used as an adsorbent in solid-phase extraction to analyze free fatty acids (FFAs) in krill oil during storage for an initial time. The Brunner Emmet Teller adsorption experiment and Fourier transform infrared spectroscopy demonstrate that NH₂-MMS, with a hierarchical pore structure, was successfully synthesized. The adsorption experiments, especially static adsorption, indicate that the absorption ability of the prepared NH₂-MMS, with a hierarchical pore structure, toward FFAs was better than that of traditional amino-modified mesoporous silica (SBA-15) with a mesoporous structure at all temperature and concentrations. Fairly low limits of detection (0.06–0.15 μg g⁻¹), acceptable recoveries (85.16–94.31%), and precision (0.08–5.26%) were attained under ideal circumstances. Moreover, NH₂-MMS has the advantages of easy preparation and being environmentally friendly. As a result, this method offers an alternative to the current method for determining FFAs in different kinds of oil specimens.

In this study, large yellow croaker (Pseudosciaena crocea) protein isolates/gellan gum (PG) binary hydrogels with dense microstructure were used for embedding and delivery curcumin (Cur). The colitis-relieving effects of PG-Cur were further investigated using the dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mouse model. Following PG-Cur treatment, weight loss, diarrhea, and shortening of the colon were significantly alleviated. Compared with the free Cur group, weight loss and colon length in the PG-Cur group increased about 1.05- and 1.12-fold. IL-1β, IL-6, TNF-α, and IL-10 levels in PG-Cur group were not significantly different from those of the normal mice, and the MPO and iNOS activities of the PG-Cur group were 29% and 20% lower than those in the Cur group, respectively. Moreover, fecal microbiota analysis of mice revealed that PG-Cur effectively restored gut dysbiosis in DSS-induced colitis, enriching beneficial bacteria while reducing harmful ones. Overall, the PG hydrogels have the potential to serve as carriers for oral curcumin formulations aimed at alleviating UC.

Phycocyanin–Cu²⁺-loaded gelatin–chitosan composite films (Gel/Cu@PC/Ch) were developed as active packaging materials to address the postharvest deterioration of fresh produce. A series of composite films with varying chitosan (Ch) concentrations (0.1%, 0.5%, 1%, 5%, w/v) were systematically fabricated and characterized. Scanning electron microscopy (SEM) revealed that the Gel/Cu@PC/Ch_0.5 film (0.5% chitosan) exhibited smooth, pore-free, and crack-free surface and cross-sectional morphologies, while a higher chitosan dosage (5%) triggered severe structural cracking. Gel/Cu@PC/Ch_0.5 achieved the maximum water contact angle of 101.13 ± 9.59°, demonstrating superior surface hydrophobicity. All composite films possessed outstanding UV-shielding capacity; meanwhile, ABTS and DPPH free radical scavenging rates rose gradually with increasing chitosan content, reaching 79.71 ± 0.72% and 84.91 ± 1.31% at 5% Ch, respectively. In antibacterial assessments, Gel/Cu@PC/Ch_0.5 showed effective inhibition against both Staphylococcus aureus and Escherichia coli, with inhibition zone diameters of 13.83 ± 0.42 mm and 14.93 ± 0.83 mm, respectively, owing to the synergistic bactericidal effect of Cu²⁺ and chitosan. In grape preservation trials conducted over 12 days, Gel/Cu@PC/Ch_0.5 wrapped grapes exhibited the lowest weight loss (3.60 ± 0.30%), retained the highest residual firmness (316.16 ± 13.81 g) and total soluble solids (TSS), and maintained a significantly higher TAC value of 0.71 ± 0.12 nM after 12 days of storage, with no visible microbial spoilage or severe shriveling observed throughout storage. These results demonstrate that the Gel/Cu@PC/Ch_0.5 composite film achieves a desirable integration of moisture barrier performance, antioxidant activity, and broad-spectrum antibacterial efficacy, offering a scalable and biodegradable platform for active food packaging in fresh fruit preservation.