Enzymatic Hydrolysis of Water Lentil (Duckweed): An Emerging Source of Proteins for the Production of Antihypertensive Fractions

Exploring novel antifungal peptides from peptic hydrolysis of chicken cruor protein via regression-based machine learning approach

There is a growing interest in natural preservatives driven by consumer demand for clean-label products. In Canada, approximately 48 million liters of blood are produced annually during chicken slaughter, offering an opportunity to valorize cruor, the solid blood component rich in hemoglobin, for use in food preservation. This study investigated the hydrolysis of chicken cruor with pepsin at pH 2, 3, 4, and 5 for 180 min to produce antimicrobial peptides. The highest degree of hydrolysis (11.70 ± 0.77 %) was observed at pH 2, similar to pH 3 where the enzyme exhibited a zipper mechanism. Hydrolysates at pH 2 and 3 inhibited fungal strains (Paecilomyces spp., Rhodotorula mucilaginosa, and Mucor racemosus) with MIC: 0.63 mM, while no antibacterial activity was observed. Partial Least Square-Discriminant Analysis (PLS-DA) allowed the identification of 31 antifungal peptides, including LARKYH, active against R. mucilaginosa (MIC: 0.63 mM), highlighting chicken cruor's potential as a source of bio-preservatives.

Machine learning-driven discovery of bioactive peptides from duckweed (Lemnaceae) protein hydrolysates: Identification and experimental validation of 20 novel antihypertensive, antidiabetic, and/or antioxidant peptides

Duckweed, a sustainable, protein-rich aquatic plant, has recently emerged as a promising source of bioactive peptides. However, their identification remains limited and challenging in such complex mixtures. Following duckweed hydrolysis with pepsin, chymotrypsin, trypsin and papain, and a centrifugation step producing two fractions: supernatant (DS) and pellet (DP), interesting half-maximal inhibitory concentration (IC50) for dipeptidyl peptidase (DPP)-IV and angiotensin-converting enzyme (ACE) inhibition were obtained for DS fractions, especially with pepsin (IC50 = 0.7 and 0.07 mg/mL, respectively). Using partial least squares-discriminant analysis (PLS-DA) combined with quantitative structure-activity relationship (QSAR) models, five new DPP-IV inhibitors (most active: API, IC50 = 126.88 μM), eleven new ACE inhibitors (most active: FAR, IC50 = 13.54 μM) and four new antioxidants (>200 μM) were identified. Two sequences were active across all three tested bioactivities, revealing promising multi-target peptides. These findings highlight the potential of duckweed-derived peptides to support health and metabolic balance.

Duckweed protein: Extraction, modification, and potential application

Discovering alternative protein sources that are both nutritious and environmentally friendly is essential to meet the growing global population's needs. Duckweed offers promise due to its cosmopolitan distribution, rapid growth, high protein content, and scalability from household tanks to large lagoons without requiring arable land that competes for the major crops. Rich in essential amino acids, particularly branched-chain amino acids, duckweed supports human health. Extraction methods, such as ultrasound and enzymatic techniques, enhance protein yield compared to traditional methods. However, low protein solubility remains a challenge, addressed by protein modification techniques (physical, chemical, and biological) to broaden its applications. Duckweed proteins hold potential as functional food ingredients due to their unique physicochemical properties. This review also includes patents and regulations related to duckweed protein, filling a gap in current literature. Overall, duckweed presents a sustainable protein source with a lower environmental impact compared to conventional crops.

Plant-Derived as Alternatives to Animal-Derived Bioactive Peptides: A Review of the Preparation, Bioactivities, Structure-Activity Relationships, and Applications in Chronic Diseases

Background/Objectives: At present, a large number of bioactive peptides have been found from plant sources with potential applications for the prevention of chronic diseases. By promoting plant-derived bioactive peptides (PDBPs), we can reduce dependence on animals, reduce greenhouse gas emissions, and protect the ecological environment. Methods: In this review, we summarize recent advances in sustainably sourced PDBPs in terms of preparation methods, biological activity, structure-activity relationships, and their use in chronic diseases. Results: Firstly, the current preparation methods of PDBPs were summarized, and the advantages and disadvantages of enzymatic method and microbial fermentation method were introduced. Secondly, the biological activities of PDBPs that have been explored are summarized, including antioxidant, antibacterial, anticancer and antihypertensive activities. Finally, based on the biological activity, the structure-activity relationship of PDBPs and its application in chronic diseases were discussed. All these provide the foundation for the development of PDBPs. However, the study of PDBPs still has some limitations. Conclusions: Overall, PDBPs is a good candidate for the prevention and treatment of chronic diseases in humans. This work provides important information for exploring the source of PDBPs, optimizing its biological activity, and accurately designing functional foods or drugs.

Comparison of characteristics and antioxidant activities of sesame protein hydrolysates and their fractions

Sesame meal is a by-product obtained from oil extraction. We investigated the characteristics and antioxidant activities of a sesame protein hydrolysate (SPH-B), as well as its peptide fractions. Four peptide fractions (F1; >100 kDa, F2; 10-100 kDa, F3; 1-10 kDa, and F4; <1 kDa) of SPH-B were prepared. The characteristics and antioxidant properties of SPH-B and its peptide fractions were evaluated. Sesame protein (SP) contained protein fractions with molecular weights ranging from 10 to 44 kDa, whereas SPH-B had peptide fractions ranging from 8 to 44 kDa. The peptide fractions had molecular weight ranging from 7 to 10 kDa. The four peptide fractions had a higher α-helix content and lower surface hydrophobicity than SPH-B and SP. They exhibited better antioxidant properties, with higher ABTS and DPPH radical scavenging activities, higher metal chelating activity, and greater inhibition of linoleic acid peroxidation, suggesting that sesame peptide fractions can use as plant-based functional ingredients and potentially health-promoting properties.