Xiaowei Zhang

Lophatherum gracile Brongn. (L. gracile) has been utilized as a food or medicinal plant for a long time. A series of chemical and spectroscopic methods was used to characterize the extracted and purified L. gracile polysaccharide (LGP). Its in vivo antitumor activity in the H22 tumor-bearing mice model was studied. LGP has a molecular weight of 1.42 × 10⁶ Da and is mainly composed of arabinose (Ara), galactose (Gal), xylose (Xyl), and other monosaccharides. NMR spectra suggest that LGP may be composed of 1,3-β-Galp and 1,3,6-β-Galp main chains, and a side chain formed by a 1,5-α-Araf short chain. The termini are composed of T-α-Araf, while [→4) -α-GalpA-(1→2)-α-Rhap-(1→] are attached to the backbone as short side chains, and the other monosaccharides are an arabinogalactan composed of the termini. SEM and AFM revealed that LGP presents a lamellar morphology with smooth surfaces and notable molecular aggregation. The Congo red assay, CD spectroscopy, and XRD collectively indicated the absence of a triple helix conformation and an overall amorphous structure in LGP. Compared with the model group, LGP treatment improved body responses, immune organs, and SOD and MDA levels. The tumor cell apoptosis rate in the high-dose LGP group was 50.0%. In the distribution of the tumor cell cycle, the proportions of the S phase were 29.1% and 41.1% in the low-dose LGP and high-dose LGP groups, respectively, compared with 12.2% in the model group. These results suggest that LGP exhibits preliminary antitumor activity, indicating its potential as a candidate for further cancer research.

BACKGROUND: Searching for natural phosphorylated peptides as thrombin inhibitors is a good strategy for coagulation intervention. Phosvitin is one of the most phosphorylated proteins and has an anticoagulant effect by inhibiting thrombin. RESULTS: The preparation of phosvitin hydrolysate was optimized by two‐step enzymatic hydrolysis in this study, resulting in a significant enhancement of its thrombin inhibitory activity. After chromatography purification, the P4 fraction exhibiting the highest thrombin inhibitory activity was isolated. It significantly prolonged the thrombin time and the activated partial thromboplastin time, indicating inhibition of the endogenous and common coagulation pathways. pSSKpSSNpSpSK, identified from the P4 fraction, exhibited a high proportion among total peptides and strong thrombin affinity, primarily binding to exosite I of thrombin via electrostatic interactions. Polyphosphorylation of peptides played a critical role in thrombin inhibition. Additionally, pSSKpSSNpSpSK may interfere with blood coagulation through the lipid and atherosclerotic signaling pathway. CONCLUSION: The present study successfully isolated polyphosphorylated peptides from phosvitin, demonstrating that their core components exert anticoagulant effects by inhibiting thrombin and interfering with signaling pathways, laying a promising theoretical foundation for developing anticoagulant functional foods. © 2025 Society of Chemical Industry.

Peptide–calcium complexes exhibit promise as calcium supplements due to their enhanced bioavailability. Phosvitin nonapeptide DEEENDQVK (DK) possesses a high calcium-binding capability. This study investigated the calcium transport-promoting properties of DK and DEEENDQVK–calcium complex (DK–Ca) using a Caco-2 monolayer model. Both DK and DK–Ca concentration-dependently promoted calcium transport, and compared with the CaCl₂ control, enhanced calcium transport by 1.07-fold and 1.83-fold, respectively. The calcium transport channels and mechanisms of DK and DK–Ca were also investigated using transfer channel regulators, real-time quantitative polymerase chain reaction, and molecular docking. The results showed that DK–Ca primarily promoted calcium transport through the TRPV6 channel, with supplementary contributions from paracellular and endocytosis channels, while DK did not rely on the endocytosis channel. DK and DK–Ca promoted calcium transport by upregulating TRPV6, calbindin-D9k, PMCA1b, and claudin-2 mRNA expression. DK–Ca exhibited a higher binding affinity for TRPV6 (−10.0 kcal/mol) compared to DK (−5.5 kcal/mol). DK–Ca primarily binds TRPV6′s extracellular exposed cavity through hydrogen bonds and hydrophobic interactions, increasing the local calcium concentration at the channel entrance to promote calcium absorption. This study provides cellular-level mechanistic clues for the potential effects of DK–Ca as a calcium supplement.

Food-derived peptides have been extensively studied for their benefits in humans. Hen eggs, characterized by high protein and digestibility, are an excellent source of food-derived bioactive peptides. This review summarizes the preparation methods, purification, and identification of hen egg-derived peptides (HEPs). The preparation methods mainly include enzymatic hydrolysis, microbial fermentation, and chemical synthesis. Genetic engineering is an emerging trend of HEP preparation. Then, we summarize the biological activities of HEPs, such as antioxidant activities, enzyme inhibitory activity, and antibacterial activity, of which the enzyme inhibitory activity is comprehensively summarized for the first time. The structure–activity relationship and underlying mechanism of the HEPs are further elucidated. Finally, the applications, future challenges, and opportunities of HEPs were mainly discussed in the food and non-food sectors. We focus on the potential applications of HEPs in intestinal health and assembly delivery and provide a reference for the further utilization and commercial development of HEPs.

BACKGROUND: Iron deficiency anemia (IDA) is one of the commonest global nutritional deficiency diseases, and the low bioavailability of iron is a key contributing factor. The peptide‐iron complex could be used as a novel iron supplement to improve iron bioavailability.RESULTS: In this study, antioxidant low molecular weight (in vitro digestion was evaluated. The results showed that PP‐4 had good ferrous‐binding activity with 96.14 ± 2.86 μg Fe²⁺ mg⁻¹, and had a strong antioxidant effect with 995.61 ± 79.75 μmol TE mg⁻¹ in 2,2'‐azinobis'3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) and 62.3 ± 3.95 μmol FeSO₄ mg⁻¹ in ferric ion reducing antioxidant power (FRAP). After ferrous binding, the FRAP activity of PP‐4‐Fe, enhanced by 1.8 times, formed a more ordered structure with an increase in α‐helix and decrease in γ‐random coil. The ferrous binding sites of PP‐4 involved were the amino, carboxyl, imidazole, and phosphate groups. The PP‐4‐Fe complex displayed excellent gastrointestinal stability and antioxidant effects during digestion. The iron dialysis percentage of PP‐4‐Fe was 74.59% ± 0.68%, and increased to 81.10% ± 0.89% with the addition of 0.25 times vitamin C (VC). This indicated that PP‐4‐Fe displayed excellent bioavailability and VC in sufficient quantities had a synergistic effect on improving bioavailability.CONCLUSIONS: This study demonstrated that antioxidant phosvitin peptide was an efficient delivery system to protect ferrous ions and suggested that the phosvitin peptide‐ferrous complex has strong potential as a ferrous supplement. © 2023 Society of Chemical Industry.

This study aimed to isolate polysaccharides from Penthorum chinense Pursh and evaluate their rheological characteristics, physicochemical properties, and antioxidant activity. The optimal conditions for the maximal extraction yield of Penthorum chinense Pursh polysaccharides (4.05 ± 0.12%) were determined by employing a single-factor test and response surface methodology which included an extraction time of 3 h, a liquid–solid ratio of 20 mL/g, and three separate extraction times. The rheological experiments showcased that the P. chinense polysaccharides exhibited typical shear-thinning behavior, with their apparent viscosity being influenced by various parameters such as concentration, pH, temperature, salt content, and freeze–thaw. The purified polysaccharides (PCP-100), having an average molecular weight of 1.46 × 10⁶ Da, mainly consisted of glucose (18.99%), arabinose (22.87%), galactose (26.72%), and galacturonic acid (21.89%). Furthermore, the PCP-100 exhibited high thermal stability and displayed an irregular sheet-like morphology. Its superior reducing power and free radical scavenging ability implied its significant antioxidant activity in vitro. Collectively, these findings provide important insights for the future application of P. chinense polysaccharides in the food industry.

丝裂原活化蛋白激酶(mitogen-activated protein kinase，MAPK)级联系统是真核生物细胞中高度保守的信号系统之一，参与诸多生物学过程的调控。在细胞因子、神经递质及激素等不同信号的刺激下，MAPK级联逐步激活下游靶因子，控制着多种细胞过程，包括生长、免疫、炎症和应激反应等。在不同细胞中，MAPK级联对细胞的作用随刺激物与刺激持续时间的不同而有所差异。MAPK级联诱导Th分化，参与T细胞受体信号通路和B细胞受体信号通路。MAPK级联调节癌症发生和发展相关的各种细胞活动。深入、系统地了解MAPK级联对各种细胞过程的特异性调控作用，将为多种疾病的靶向治疗提供理论指导。