Liang Tao

A novel calcium-chelating peptide, KTFQGPPHG, was identified and screened from Moringa oleifera Lam. leaf protein hydrolysate, and further used to prepare a highly stable peptide–calcium chelate (KTFQGPPHG-Ca). The structure of KTFQGPPHG-Ca was characterized, while assessing its chelation stability and calcium transport potential. It was found that the calcium binding capacity of KTFQGPPHG reached 62.401 µg/mg. After chelation with calcium, KTFQGPPHG transitioned from an amorphous structure to a stable crystalline form. Carboxyl oxygen atoms and amino nitrogen atoms on KTFQGPPHG served as binding sites for Ca²⁺. The KTFQGPPHG-Ca demonstrates excellent phosphate stability and thermal stability. In addition, the calcium transport amount of KTFQGPPHG at 30 min and 60 min was significantly higher than that of the CaCl₂ group (p < 0.05). Particularly, the calcium transport capacity at 30 min was 1.40-fold that of the CaCl₂ group. KTFQGPPHG effectively counteracted the suppressive impact of dietary factors on Ca²⁺ absorption, and likely promoted Ca²⁺ translocation via the TRPV6 calcium channel pathway. The present results offer a theoretical basis for KTFQGPPHG-Ca to serve as a promising calcium source to improve intestinal calcium absorption.

This study aimed to address the poor bioavailability of traditional calcium supplements by investigating the Moringa oleifera Lam. leaf-derived peptide KTFQGPPHG and its peptide-calcium chelate. Virtual screening predicted potential interactions of KTFQGPPHG with Ca2+ and calcium transport-related proteins, including TRPV6, Cav1.3, and PepT1. During simulated digestion, KTFQGPPHG-Ca showed high intestinal-phase stability, with a calcium retention rate of 94.13 ± 1.47%, while its major digestive fragment, TFQGPPHG, retained substantial calcium-binding activity. In Caco-2 cell monolayers, both KTFQGPPHG-Ca and TFQGPPHG-Ca significantly enhanced calcium transport compared with CaCl2, with Cav1.3 and TRPV6 being major pathways involved in this process. Proteomic analysis suggested that these chelates may regulate calcium absorption-associated epithelial pathways, including “cell adhesion molecules” and “ECM–receptor interaction,” which may contribute to epithelial barrier integrity and cell-matrix signaling associated with Ca2+ transport. In conclusion, KTFQGPPHG-Ca exhibits high gastrointestinal stability and enhances calcium transport through multiple pathways, supporting its potential development as a novel calcium supplement.

This study aimed to systematically compare the functional properties of the four major components (albumin, globulin, prolamin, and glutelin) of protein from Yunnan deep-veined walnuts to screen for protein-based carrier materials with good processing adaptability and the ability to efficiently encapsulate the active ingredient rutin. In addition, the binding and molecular interactions between the preferred protein and rutin were analyzed. The results indicated that albumin exhibited superior performance compared to the other three components in solubility, emulsifying properties, foaming properties, and gel properties, and demonstrated the strongest processing applicability. Further analysis revealed that albumin possessed an excellent amino acid composition (essential amino acid content accounting for 42.30%) and antioxidant activity (with the highest ABTS scavenging rate reaching 85.71 ± 0.26%), which indicated its considerable potential as a functional carrier. Loading rutin onto albumin yielded a walnut albumin–rutin complex (WA@Rut), which significantly enhanced the thermal stability of albumin (with the thermal denaturation temperature elevated to 108.72 °C) and the storage stability of rutin (66.16 ± 5.05% retention after 22 days of storage). Combined analyses of FT-IR spectroscopy, intrinsic fluorescence spectroscopy, molecular docking, and molecular dynamics simulations confirmed that rutin primarily bound to albumin via hydrogen bonding and electrostatic interactions, and formed a stable complex structure. SEM images revealed that the composite surface was smooth and exhibited a flake-like morphology. In conclusion, walnut albumin is a protein resource with significant functional potential in Yunnan deep-veined walnuts, and it exhibits strong processing applicability and enables efficient encapsulation and protection of active ingredients. This study provides novel strategies and theoretical foundations for the high-value utilization of walnut protein.

Selenium nanoparticles (SeNPs) have drawn considerable attention to biomedicine, the food industry, and cosmetics due to their strong antioxidant potential and low toxicity. However, their poor stability limits broader applications. A promising strategy to overcome this limitation involves combining SeNPs with polysaccharides. In this study, selenium nanoparticles (MOLP-SeNPs) were synthesized using Moringa oleifera Lam. polysaccharide (MOLP) as a stabilizer and dispersant within a redox system comprising sodium selenite and ascorbic acid. The structural characteristics of the synthesized MOLP-SeNPs were analyzed using spectroscopy. Additionally, their thermal and storage stability was evaluated, and their antioxidant activity was explored through simulated digestion in vitro and a HepG2 cell oxidative stress model. The results demonstrated that well-dispersed, zero-valent MOLP-SeNPs showing a mean particle size of 166.58 nm were synthesized successfully through an MOLP-to-sodium selenite ratio of 2.8:3 at pH 7.3 and 35 °C. The MOLP-SeNPs exhibited excellent stability during preparation. In simulated in vitro digestion and H₂O₂-induced oxidative stress experiments on HepG2 cells, MOLP-SeNPs displayed strong free radical scavenging capacity while improving antioxidant activity. Cellular experiments deeply revealed that pretreatment with MOLP-SeNPs significantly improved cell viability and provided a pronounced protective effect against oxidative damage. In conclusion, MOLP-SeNPs represent a novel antioxidant with promising applications in food and biomedicine.

Diabetic cognitive dysfunction is one of the important comorbidities and complications of diabetes, which is mainly manifested by loss of learning ability and memory, behavioural disorders, and may even develop into dementia. While traditional anti-diabetic medications are effective in improving cognition and memory, long-term use of these medications can be accompanied by undesirable side effects. Therefore, there is an urgent need to find safe and effective alternative therapies. Accumulating evidence suggests that phytogenic bioactive peptides play an important role in the regulation of cognitive dysfunction in diabetes. In this review, we explored the relationship between diabetes mellitus and cognitive dysfunction, and the potential and underlying mechanisms of plant-derived bioactive peptides to improve diabetic cognitive dysfunction. We found that plant-derived active peptides alleviate diabetic cognitive impairment by inhibiting key enzymes (e.g., α-glucosidase, α-amylase) to improve blood glucose levels and increase antioxidant activity, modulate inflammatory mediators, and address intestinal dysbiosis. In conclusion, plant-derived active peptides show strong potential to improve diabetic cognitive impairment.

Background: In this study, deep eutectic solvents (DESs) combined with ultrasound-assisted extraction (UAE) were used to extract bioactive compounds from the leaves of Moringa oleifera Lam.Methods: The FT-IR method was used to analyze the structural characteristics of the DESs, and the extraction efficiencies of the DESs for total phenolic content (TPC) and total flavonoid content (TFC) were evaluated. The stability of the extracts under high temperature and UV radiation was assessed, and their antioxidant activity was investigated after undergoing in vitro simulated digestion.Results: The results show that the seven DESs extracted more TPC and TFC than did the 70% ethanol (36.27 ± 1.58 mg GAE/g, 23.09 ± 1.47 mg RT/g), and the extraction process of UAE-DES was optimized by selecting choline chloride: citric acid as the DES solvent, which has the highest extraction of TPC (86.92 ± 1.34 mg GAE/g) and TFC (49.73 ± 0.85 mg RT/g). The stability results indicated that the DES phenolic extracts were less stable when exposed to high temperature and UV radiation, indicating that DES extracts have better bioactivity. Moreover, after in vitro simulated digestion, the DES extract shows a higher DPPH free radical scavenging capacity (12.79 ± 3.88 mmol Trolox/g of DES extracts, 6.99 ± 4.02 mmol Trolox/g of ethanol extracts) and ferric ion reducing antioxidant power (62.61 ± 1.71 mmol Trolox/g of DES extracts, 55.07 ± 1.66 mmol Trolox/g of ethanol extracts) than ethanol extracts.Conclusion: This study confirmed that DESs are a new and environmentally friendly solvent that can be used for the extraction of phenolic compounds.