Bioactive food derived peptides: a review on correlation between structure of bioactive peptides and their functional properties

Improvement of egg yolk powder properties through ultrasound coupled sodium sulfite pretreatment assisted enzymatic hydrolysis and underlying mechanism

Egg yolk is an excellent protein source for the production of bioactive peptides. However, the recent method need to remove lipid first which involves wastage and pollution of organic reagents. Therefore, the process of directly using oily yolk powder to prepare egg yolk peptides has attracted much attention. This study developed a one-step process to simultaneously extract oil and hydrolyze proteins based on an ultrasound coupled sodium sulfite pretreatment (UCSSP) assisted enzymatic hydrolysis for egg yolk powder. Results showed that UCSSP increased the oil extraction rate from zero to 75 % with 59.35 g/L of soluble protein and 33.99 g/L of peptide. Further analysis of the underlying mechanism demonstrated that ultrasound pre-treatment could change the secondary structure of EYP while sodium sulfite pre-treatment softened the protein and induced more hydrophobic groups exposed, thus inducing more lipoprotein released for hydrolysis. In addition, the proportion of peptides ranging from 180 Da to 3000 Da in the UCSSP group increased from 31.19 % before to 79.74 %, which was 31.27 % and 6.16 % higher than that of UP and SP. Furthermore, the obtained peptides showed obvious activities in uric acid-lowering, anti-obesity and antioxidant with 56.24 % inhibition in XOD activity and close antioxidant activity to vitamin C, implying it a potential health product.

ESMR4FBP: A pLM-based regression prediction model for specific properties of food-derived peptides optimized multiple bionic metaheuristic algorithms

Due to the growing emphasis on food safety, peptide research is increasingly focusing on food sources. Traditional methods for determining peptide properties are expensive. While artificial intelligence (AI) models can reduce cost, existing peptide models often lack accuracy. This study aimed to develop a regression model capable of predicting peptide properties. We integrated the ESM-2 model with the LSTM architecture and optimized the model structure using three metaheuristic algorithms, including WOA, SSA, and HHO. Using an antioxidant tripeptide dataset, our model achieved an R2 of 0.9458 and RMSE of 0.3135, outperforming the state-of-the-art (SOTA) model by 11.66 % and 50.00 %, respectively. The developed model was further applied to the bitter peptide dataset, resulting in R2 of 0.8385 and RMSE of 0.4414, respectively. These results suggest that our model has the potential to accurately predict the properties of various types of peptides.

Novel bioactive peptides alleviate Western diet-induced MAFLD in C57BL/6J mice by inhibiting NLRP3 inflammasome activation and pyroptosis via TLR4/NF-κB and Keap1/Nrf2/HO-1 signaling pathways

Metabolic-associated fatty liver disease (MAFLD) has emerged as a leading chronic liver disease. This condition is characterized by an abnormal accumulation of fat within liver and can progress from simple steatosis to more severe stages involving chronic inflammation and oxidative stress. In this study, we investigated the potential therapeutic effects and underlying mechanism of novel bioactive peptides (EWYF and EWFY) on Western diet-induced MAFLD in C57BL/6J mice. Mice fed a normal chow diet (ND group) and Western diet (WD and treatment groups) for 8 weeks. Treatment groups received EWYF and EWFY peptides in low (10 mg/kg/day) and high (50 mg/kg/day) doses were divided into four groups: EWYF10, EWYF50, EWFY10, and EWFY50. Western diet-induced body weight gain and increased liver weight along with visceral adiposity, which were markedly reversed by bioactive peptides in a dose-dependent manner. Additionally, bioactive peptides significantly reduced hepatic steatosis, liver injury and proinflammatory response. Western diet-induced glucose tolerance and insulin resistance, whereas bioactive peptides significantly improved glucose tolerance and insulin sensitivity. Persistent intake of Western diet triggered chronic inflammation and severe oxidative stress, which were significantly alleviated by bioactive peptides treatment via inhibiting NOD-like receptor protein 3 (NLRP3) inflammasome activation and mitigated pyroptosis by modulating TLR4/NF-κB and Keap1/Nrf2/HO-1 signaling pathways. Furthermore, molecular docking studies suggest that EWYF and EWFY act as fructokinase antagonists and TLR4 inhibitors, which potentially alleviates Western diet-induced MAFLD. Collectively, these findings highlight EWYF and EWFY as promising candidates for MAFLD treatment due to their potent antioxidant and anti-inflammatory properties via specific molecular inhibition.

High-Accuracy Identification and Structure-Activity Analysis of Antioxidant Peptides via Deep Learning and Quantum Chemistry

Antioxidant peptides (AOPs) hold great promise for mitigating oxidative-stress-related diseases, but their discovery is hindered by inefficient and time-consuming traditional methods. To address this, we developed an innovative framework combining machine learning and quantum chemistry to accelerate AOP identification and analyze structure-activity relationships. A Bi-LSTM-based model, AOPP, achieved superior performance with accuracies of 0.9043 and 0.9267, precisions of 0.9767 and 0.9848, and Matthews correlation coefficients (MCCs) of 0.818 and 0.859 on two data sets, outperforming existing methods. Compared with XGBoost and LightGBM, AOPP demonstrated a 4.67% improvement in accuracy. Feature fusion significantly enhanced classification, as validated by UMAP visualization. Experimental validation of ten peptides confirmed the antioxidant activity, with LLA exhibiting the highest DPPH and ABTS scavenging rates (0.108 and 0.437 mmol/g, respectively). Quantum chemical calculations identified LLA's lowest HOMO-LUMO gap (ΔE = 0.26 eV) and C3-H26 as the key active site contributing to its superior antioxidant potential. This study highlights the synergy of machine learning and quantum chemistry, offering an efficient framework for AOP discovery with broad applications in therapeutics and functional foods.

Perch Hydrolysates from Upcycling of Perch Side Streams Accelerate Wound Healing by Enhancing Fibroblasts to Secrete Procollagen I, Fibronectin, and Hyaluronan

Wound healing incurs various challenges, making it an important topic in medicine. Short-chain peptides from fish protein hydrolysates possess wound healing properties that may represent a solution. In this study, perch hydrolysates were produced from perch side steams using a designed commercial complex enzyme via a proprietary pressure extraction technique. The average molecular weight of the perch peptides was 1289 kDa, and 62.60% of the peptides had a low molecular weight (≤1 kDa). Similarly to the beneficial amino acid sequence FPSIVGRP, FPSLVRGP accounted for 6.21% abundance may have a potential antihypertensive effect. The concentrations of collagen composition and branched-chain amino acids were 1183 and 1122 mg/100 g, respectively. In a fibroblast model, active perch peptides accelerated wound healing mainly by increasing the secretion of procollagen I, fibronectin, and hyaluronan. In an SD rat model established to mimic human wounds, orally administered perch hydrolysates with a molecular weight below 2.3 kDa accelerated wound healing, which mainly resulted from collagen-forming amino acids, branched-chain amino acids, and matrikine. Collectively, the residue of perch extract can be upcycled via a hydrolysis technique to produce not only bioactive sequences but also short-chain peptides. Considering the therapeutic potential to promote wound healing, such by-products are of great value and may be developed as dietary nutraceuticals.

Impact of chia seed protein hydrolysate and apple pomace pectin on the properties of egg-free mayonnaise

This study investigates the properties of egg-free mayonnaise prepared using chia seed protein hydrolysate (CSPH) and pectin extracted from apple pomace (PA) as alternatives to egg, comparing it to traditional egg-based mayonnaise. Chia seed protein was hydrolyzed using Protamex and Bromelain enzymes, while apple pectin was extracted through acid hydrolysis at 90 °C. Four mayonnaise treatments were prepared: T1 (control: 6 % egg), T2 (4 % egg + 1 % CSPH + 1 % PA), T3 (2 % egg + 2 % CSPH + 2 % PA), and T4 (0 % egg + 3 % CSPH + 3 % PA). The physicochemical, textural, and sensory properties of the mayonnaise samples were evaluated. The CSPH produced with the Protamex enzyme exhibited a higher protein content and greater degree of hydrolysis (P < 0.05), establishing it as a suitable egg substitute. Replacing egg with CSPH and PA resulted in increased acidity, physical and thermal stability, viscosity, firmness, and adhesiveness of the mayonnaise, while reducing lightness, pH, and overall sensory scores. Treatments T3 and T4 demonstrated superior overall properties compared to other treatments; however, T3 received the highest sensory scores. These findings suggest that pectin and hydrolyzed protein can effectively replace egg in mayonnaise production, offering a viable alternative for individuals with egg allergies and those seeking healthier options.

Virtual screening and evaluation of bioactive peptides from Haliotis discus hannai as potential HMGCR inhibitors for hyperlipidemia treatment

Introduction

Hyperlipidemia remains a major disease threatening global public health. The morbidity and mortality associated with cardiovascular diseases have been increasing. The inhibition of 3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), a key enzyme in the cholesterol synthesis pathway, can effectively reduce cholesterol levels.

Methods and results

In this study, the most suitable protease for preparing HMGCR inhibitory peptides was screened using the evaluation indexes of peptide yield and HMGCR inhibition rate. Peptide sequences with molecular weights <1 kDa were identified, and peptide fragments were docked with HMGCR for virtual screening. The inhibitory effects of these peptides on HMGCR activity were evaluated in vitro using a high-fat Hep-G2 cell model. The screened peptides possessed significant HMGCR inhibitory activity and reduced cholesterol micelle solubility and total cholesterol and triglyceride levels in hyperlipidemic Hep-G2 cells.

Conclusion

This study provides novel insights into developing natural drugs for hyperlipidemia; moreover, the results will facilitate the functional application of marine bioactive peptides.

Research Progress of Food-Derived Antihypertensive Peptides in Regulating the Key Factors of the Renin-Angiotensin System

Food protein-derived antihypertensive peptides have attracted substantial attention as a safer alternative for drugs. The regulation of the renin-angiotensin system (RAS) is an essential aspect underlying the mechanisms of antihypertensive peptides. Most of the identified antihypertensive peptides exhibit the angiotensin-converting enzyme (ACE) inhibitory effect. In addition, artificial intelligence has improved the efficiency of ACE inhibitory peptide identifications. Moreover, the inhibition of renin and blockade or down-regulation of angiotensin type I receptor (AT1R) have also been demonstrated to be effective intervention strategies. With the identification of the ACE2/Ang (1-7)/MasR axis, activation or up-regulation of angiotensin-converting enzyme 2 (ACE2) has also emerged as a new intervention pathway. This review summarizes the research progress of antihypertensive peptides in intervening with hypertension from the perspective of their properties, sources, and key factors. The objective of this review is to provide theoretical references for the development of antihypertensive peptides and the explorations of the molecular mechanisms.

Bioactive Peptides in Greek Goat Colostrum: Relevance to Human Metabolism

Colostrum is essential for the survival and development of newborn mammals. This primary source of nourishment during the first days of infant life is rich in functional components conductive to the enhancement of neonate immunity and growth. Compared with mature milk, a higher protein and peptide content is observed in colostrum, whilst it is low in fat and carbohydrates. The functional properties of colostrum are closely linked to the release of bioactive peptides during the gastrointestinal digestion of colostrum proteins. Our study aimed to comprehensively analyze the whey proteome of colostrum from indigenous Greek goats and to examine the influence of bioactive peptides released during digestion on human metabolism. Colostrum and mature milk samples from healthy ewes were subjected to nanoLC-MS/MS analysis, revealing differentially expressed proteins. These proteins were functionally characterized and subjected to in silico digestion. Using machine learning models, we classified the peptide functional groups, while molecular docking assessed the binding affinity of the proposed angiotensin-converting enzyme (ACE)- and dipeptidyl peptidase IV (DPPIV)-inhibitory peptides to their target molecules. A total of 898 proteins were identified in colostrum, 40 of which were overexpressed compared with mature milk. The enzymatic cleavage of upregulated proteins by key gastrointestinal tract proteases and the downstream analysis of peptide sequences identified 117 peptides predicted (with >80% confidence) to impact metabolism, primarily through modulation of the renin-angiotensin system, insulin secretion, and redox pathways. This work advances our understanding of dietary bioactive peptides and their relevance to human metabolism, highlighting the potential health benefits of colostrum consumption.

Effect of nanoemulsified and encapsulated Planiliza abu protein on fortified yogurt

Fortified dairy products such as yogurt have attracted a lot of attention due to the increasing concern for public health. This study aimed to determine the effects of nanoemulsified and a microencapsulated protein hydrolysate obtained from Planiliza abu on some of the properties of yogurt. The physicochemical, rheological, microbiological, and sensory evaluation of the fortified yogurt samples stored at 4°C were assessed during 21 days. The fish protein hydrolysates (FPHs) < or >10 kDa protein were used. The amino acid profile of Planiliza abu was glutamic acid (78.99%), aspartic acid (59.53%), and lysine (53.54%). No significant change was observed in titratable acidity (TA) and pH of supplemented yogurts during refrigeration. The highest survival level of lactic acid bacteria (LAB), water-holding capacity (WHC), and viscosity and the lowest syneresis were observed in fortified samples with FPH <10 kDa. The highest ferric reducing antioxidant power (FRAP) was achieved in yogurt fortified with nanoemulsion FPH < 10 kDa (NEh10a, 0.41 mg/g). The results showed that fortified yogurt with FPH, particularly less than 10 kDa, is among the desirable functional food with appropriate gel network and consistency as well as better taste and mouth feel, and higher overall acceptance.

In vitro evaluation of multifunctional peptides PW, PF, PPG, PM, IW, and SW for metabolic syndrome management

Multifunctional peptides derived from various food sources, including ancestral grains, hold significant promise for managing metabolic syndrome. These bioactive peptides exhibit diverse properties that collectively contribute to improving the components of metabolic syndrome. In this study, we investigated the in vitro multifunctionality of six peptides (PW, PM, SW, PPG, PW, and IW) identified through in silico analysis and chemically synthesized. These peptides were evaluated for their potential to address metabolic syndrome-related activities such as antidiabetic, antiobesity, antihypertensive, and antioxidative properties. Assessment included their capacity to inhibit key enzymes associated with these activities, as well as their free radical scavenging and cellular antioxidative activities. Principal component analysis was employed to cluster the peptides according to their multifunctionality. Our results revealed that peptides containing tryptophan (SW, PW, and IW) exhibited the most promising multifunctional attributes, with SW showing particularly high potential. This multifunctional peptide represents a promising avenue for addressing metabolic syndrome.

Moringa oleifera Lam. Leaf Peptides: Antioxidant and Antiproliferative Activity in Human Colon Cancer Caco-2 Cell Line

Reactive oxygen species are produced as part of the cellular metabolism. However, lifestyle can promote an excess in their concentration. Free radicals react with DNA, promoting the appearance of cancer cells. Therefore, natural antioxidants have been suggested as an alternative to prevent this disorder. Peptides are protein fragments that have been produced from various plants. In previous work, Moringa oleifera leaf peptides (MOPHs) with antioxidant potential were generated and identified. However, the spectrophotometric methods used to evaluate their antioxidant activity do not fully reflect its potential. In this work, the antioxidant activity of MOPHs was assessed by the ferric reducing antioxidant power assay (FRAP) and cellular antioxidant activity method on the human colon cancer cell line Caco-2. Also, their antiproliferative activity was evaluated. The MOPHs exhibited a FRAP activity of 1435 µmol TE/g, and at 500 µg/mL; the peptides did not show a cytotoxic effect on healthy colon CCD-18Co cells. Moreover, the MOPHs increased Caco-2 antioxidative activity to a greater extent by 73.45% and 83.62% at 250 and 500 µg/mL, respectively. Regarding cellular proliferation, the MOPHs inhibited it by 78.19% and 90.20% at 200 and 500 µg/mL, respectively. These findings highlight the potential of Moringa oleifera leaf peptides as functional ingredients with significant health benefits, demonstrating antioxidant and antiproliferative properties.

Crude Garden Cress Seed Oil (Lepidium sativum Linn.) Enhances Post-Thawed Boar Sperm Quality

This study aimed to examine the effects of crude garden cress seed oil (CGCSO) on frozen-thawed boar sperm qualities. Semen ejaculates (n = 12) were collected and further divided into six equal aliquots based on CGCSO concentrations (0, 0.5, 1, 1.5, 2, and 2.5% v/v) in the freezing extender. Semen samples were processed and cryopreserved utilizing the traditional liquid nitrogen vapor technique. Subsequently, semen samples were thawed in a thermos with warm water at 50 °C for 12 s and evaluated for sperm morphology using scanning electron microscopy, sperm motility using a CASA, sperm viability, acrosome integrity, mitochondrial function, MDA level, total antioxidant capacity (TAC), glutathione peroxidase (GSH-Px), and catalase (CAT) activity. The results indicated that 1% CGCSO resulted in superior post-thaw sperm characteristics, including enhanced sperm morphology, motility, viability, acrosome integrity, and mitochondrial function. Particularly, the total motile sperm increased by 16.5%, progressive motile sperm increased by 13.0%, viability improved by 15.1%, acrosome integrity increased by 14%, and mitochondrial function improved by 14.1% compared to the control group. CGCSO treatment at 1% and 1.5% exhibited the lowest level of MDA (45.73 ± 11.2 and 45.73 ± 11.3 µmol/L, respectively) compared to the other groups. The CGCSO-supplemented groups showed higher values of TAC, GSH-Px, and CAT than the control group but not significantly.

Physicochemical and Antioxidative Properties of Protein Hydrolysates from Residual Goat Placenta Extract by Two Different Methods

Protein hydrolysates from the goat placenta provide multiple benefits, such as immune system enhancement, antioxidant activities, and reductions in uric acid levels. Despite these benefits, their industrial applications have been underexplored. This study aimed to prepare extract protein hydrolysates (GPERPs) from residual goat placenta extract (GPER) and assess their functional properties, focusing on how different drying methods influence these properties. The essential amino acid contents were 30.94% for the GPER and 34.11% for the GPERPs. Moreover, all the essential amino acids were present, and the amino acid score (AAS) for each exceeded 1.0 in the GPERPs. The foaming properties of the spray-dried GPERPs (95.56 ± 5.89%) were significantly greater than those of the freeze-dried GPERPs (49.13 ± 4.17%) at pH values of 4.0~10.0. The emulsion stability (ES) of the spray-dried GPERPs (453.44 ± 8.13 min) was notably greater than that of the freeze-dried GPERPs (245.58 ± 7.12 min). Furthermore, the water retention capacity (WRC) of the freeze-dried GPERPs (201.49 ± 6.12%) was significantly greater than that of the spray-dried GPERPs (103.35 ± 7.13%), except at pH 10.0 (101.44 ± 8.13%). Similarly, at pH values of 6.0, 8.0, and 10.0, the oil retention capacity (ORC) of the freeze-dried GPERPs (715.58 ± 12.15%) was significantly greater than that of the spray-dried GPERPs (560.56 ± 11.15%), although the opposite trend was noted under acidic conditions. In terms of the antioxidant activity, the ability of the goat placenta extract residual protein hydrolysates (GPERPs) to scavenge DPPH radicals and superoxide anion radicals increased with the increasing peptide powder concentration, and the maximum scavenging rates of the DPPH radicals (39.5 ± 0.56%) and superoxide anions (81.2 ± 0.54%) in the freeze-dried peptide powder were greater than those in the spray-dried peptide powder. These findings contribute to the understanding of the physicochemical and antioxidant properties of GPERPs under various drying methods and provide fundamental data for the development of functional foods based on GPERPs.

Characteristics and Bioactivities of Protein Hydrolysate from Cricket (Acheta domesticus) Powder Defatted Using Ethanol with Aid of Vacuum Impregnation

Cricket is a potential proteinaceous source used for protein hydrolysate (PH) preparation, having several biological activities. Nevertheless, cricket has high lipid contents, which are susceptible to oxidation during PH preparation. Thus, ethanol was used together with vacuum impregnation (VI) to enhance defatting efficacy before PH preparation. Also, bioavailability of the digest of PH after gastrointestinal tract (GIT) digestion via the Caco-2 monolayer was assessed. Cricket powder was defatted using ethanol for 1-4 h. Lipid contents were decreased with enhancing time until 2 h. Additionally, the defatting efficacy was augmented when ethanol combined with VI at 4 cycles for 2 h (VI-E-2) was implemented. Lowered mono- and polyunsaturated fatty acid contents were also observed in the VI-E-2 sample. The VI-E-2 sample was used to prepare PH using Alcalase and Flavourzyme (0.2-0.4 units/g dry sample). PH prepared by Alcalase hydrolysis at 0.2 units/g dry sample (A-0.2) showed the higher ABTS radical-scavenging activity and FRAP, compared to that prepared by Flavourzyme hydrolysis (p < 0.05). Thus, the A-0.2 sample was selected for digestion via the GIT system. The obtained digest (500-1000 μg/mL) had bioavailability of peptides, depending on the levels used. Therefore, PH from defatted cricket powder could be a promising ingredient for food applications.

Research progress on the protection and mechanism of active peptides in Alzheimer's disease and Parkinson's disease

Neurodegenerative diseases are the main causes of death and morbidity among elderly people worldwide. From the pathological point of view, oxidative stress, neuroinflammation, mitochondrial damage and apoptosis are the causes of neuronal diseases, and play a harmful role in the process of neuronal cell death and neurodegeneration. The most common neurodegenerative diseases are Alzheimer's disease(AD) and Parkinson's disease(PD), and there is no effective treatment. The physiological role of active peptides in the human body is significant. Modern medical research has found that animal and plant peptides, natural peptides in human body, can act on the central nervous system, and their active components can improve learning and memory ability, and play the roles of antioxidation, anti-inflammation, anti-apoptosis and maintaining the structure and function of mitochondria. This review reviews the reports on neurodegenerative diseases such as AD and PD by active peptides from animals and plants and natural peptides from the human body, and summarizes the neuroprotective mechanism of peptides. A theoretical basis for further research and development of active peptides was provided by examining the research and application of peptides, which provided a theoretical basis for further research and development.

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.

Is there sufficient evidence to support the health benefits of including donkey milk in the diet?

Donkey milk has attracted attention due to its distinctive nutritional composition and potential health advantages, particularly because of its whey protein content, which includes lysozyme, α-lactalbumin, lactoferrin, and β-lactoglobulin and vitamin C, among other components. These elements contribute to immunoregulatory, antimicrobial, antioxidant, and anti-inflammatory properties, positioning donkey milk as a possible therapeutic option. In addition, due to the low levels of caseins, the casein-to-whey protein ratio, and the β-lactoglobulin content in donkey milk, it presents an optimal alternative for infant formula for individuals with cow's milk allergies. Moreover, research into donkey milk's potential for cancer prevention, diabetes management, and as a treatment for various diseases is ongoing, thanks to its bioactive peptides and components. Nevertheless, challenges such as its low production yield and the not fully understood mechanisms behind its potential therapeutic role necessitate more thorough investigation. This review consolidates the existing knowledge on the therapeutic possibilities of donkey milk, emphasizing its importance for human health and the need for more detailed studies to confirm its health benefits.

A Review on Fish Skin-Derived Gelatin: Elucidating the Gelatin Peptides-Preparation, Bioactivity, Mechanistic Insights, and Strategies for Stability Improvement

Fish skin-derived gelatin has garnered significant attention recently due to its abundant availability and promising bioactive properties. This comprehensive review elucidates various intricacies concerning fish skin-derived gelatin peptides, including their preparation techniques, bioactive profiles, underlying mechanisms, and methods for stability enhancement. The review investigates diverse extraction methods and processing approaches for acquiring gelatin peptides from fish skin, emphasizing their impact on the peptide composition and functional characteristics. Furthermore, the review examines the manifold bioactivities demonstrated by fish skin-derived gelatin peptides, encompassing antioxidant, antimicrobial, anti-inflammatory, and anticancer properties, elucidating their potential roles in functional food products, pharmaceuticals, and nutraceuticals. Further, mechanistic insights into the functioning of gelatin peptides are explored, shedding light on their interactions with biological targets and pathways. Additionally, strategies aimed at improving the stability of gelatin peptides, such as encapsulation, modification, and integration into delivery systems, are discussed to extend the shelf life and preserve the bioactivity. Overall, this comprehensive review offers valuable insights into using fish skin-derived gelatin peptides as functional ingredients, providing perspectives for future research endeavors and industrial applications within food science, health, and biotechnology.

Preparation, typical structural characteristics and relieving effects on osteoarthritis of squid cartilage type II collagen peptides

The promoting effects of collagen and its derivatives on bone health have been uncovered. However, the structure and effects of type II collagen peptides from squid cartilage (SCIIP) on osteoarthritis still need to be clarified. In this study, SCIIP was prepared from squid throat cartilage with pretreatment by 0.2 mol/L NaOH at a liquid-solid ratio of 10:1 for 18 h and hydrolyzation using alkaline protease and flavourzyme at 50 °C for 4 h. The structure of SCIIP was characterized as a molecular weight lower than 5 kDa (accounting for 87.7 %), a high glycine level of 35.0 %, typical FTIR and CD features of collagen peptides, and a repetitive sequence of Gly-X-Y. GP(Hyp)GPD and GPAGP(Hyp)GD were separated and identified from SCIIP, and their binding energies with TLR4/MD-2 were - 8.4 and - 8.0 kcal/mol, respectively. SCIIP effectively inhibited NO production in RAW264.7 macrophages and alleviated osteoarthritis in rats through the TLR4/NF-κB pathway. Therefore, SCIIP exhibited the potential for application as an anti-osteoarthritis supplement.

Advances in the application and mechanism of bioactive peptides in the treatment of inflammation

Inflammation is a normal immune response in organisms, but it often triggers chronic diseases such as colitis and arthritis. Currently, the most widely used anti-inflammatory drugs are non-steroidal anti-inflammatory drugs, albeit they are accompanied by various adverse effects such as hypertension and renal dysfunction. Bioactive peptides (BAPs) provide therapeutic benefits for inflammation and mitigate side effects. Herein, this review focuses on the therapeutic effects of various BAPs on inflammation in different body parts. Emphasis is placed on the immunomodulatory mechanisms of BAPs in treating inflammation, such as regulating the release of inflammatory mediators, modulating MAPK and NF-κB signaling pathways, and reducing oxidative stress reactions for immunomodulation. This review aims to provide a reference for the function, application, and anti-inflammation mechanisms of BAPs.

Bioactive peptides of marine organisms: Roles in the reduction and control of cardiovascular diseases

Cardiovascular diseases (CVDs) affect the quality of life or are fatal in the worst cases, resulting in a significant economic and social burden. Therefore, there is an urgent need to invent functional products or drugs for improving patient health and alleviating and controlling these diseases. Marine bioactive peptides reduce and control CVDs. Many of the predisposing factors triggering CVDs can be alleviated by consuming functional foods containing marine biopeptides. Therefore, improving CVD incidence through the use of effective biopeptide foods from marine sources has attracted increasing interest and attention. This review reports information on bioactive peptides derived from various marine organisms, focusing on the process of the separation, purification, and identification of biological peptides, biological characteristics, and functional food for promoting cardiovascular health. Increasing evidence shows that the bioactivity and safety of marine peptides significantly impact their storage, purification, and processing. It is feasible to develop further strategies involving functional foods to treat CVDs through effective safety testing methods. Future work should focus on producing high-quality marine peptides and applying them in the food and drug industry.

Exploring the impact of encapsulation on the stability and bioactivity of peptides extracted from botanical sources: trends and opportunities

Bioactive peptides derived from plant sources have gained significant attention for their potential use in preventing and treating chronic degenerative diseases. However, the efficacy of these peptides depends on their bioaccessibility, bioavailability, and stability. Encapsulation is a promising strategy for improving the therapeutic use of these compounds. It enhances their stability, prolongs their shelf life, protects them from degradation during digestion, and enables better release control by improving their bioaccessibility and bioavailability. This review aims to analyze the impact of various factors related to peptide encapsulation on their stability and release to enhance their biological activity. To achieve this, it is necessary to determine the composition and physicochemical properties of the capsule, which are influenced by the wall materials, encapsulation technique, and operating conditions. Furthermore, for peptide encapsulation, their charge, size, and hydrophobicity must be considered. Recent research has focused on the advancement of novel encapsulation methodologies that permit the formation of uniform capsules in terms of size and shape. In addition, it explores novel wall materials, including polysaccharides derived from unconventional sources, that allow the precise regulation of the rate at which peptides are released into the intestine.

Angiotensin-Converting Enzyme and Renin-Inhibitory Activities of Protein Hydrolysates Produced by Alcalase Hydrolysis of Peanut Protein

Hypertension is a major controllable risk factor associated with cardiovascular disease (CVD) and overall mortality worldwide. Most people with hypertension must take medications that are effective in blood pressure management but cause many side effects. Thus, it is important to explore safer antihypertensive alternatives to regulate blood pressure. In this study, peanut protein concentrate (PPC) was hydrolyzed with 3-5% Alcalase for 3-10 h. The in vitro angiotensin-converting enzyme (ACE) and renin-inhibitory activities of the resulting peanut protein hydrolysate (PPH) samples and their fractions of different molecular weight ranges were determined as two measures of their antihypertensive potentials. The results show that the crude PPH produced at 4% Alcalase for 6 h of hydrolysis had the highest ACE-inhibitory activity with IC50 being 5.45 mg/mL. The PPH samples produced with 3-5% Alcalase hydrolysis for 6-8 h also displayed substantial renin-inhibitory activities, which is a great advantage over the animal protein-derived bioactive peptides or hydrolysate. Remarkably higher ACE- and renin-inhibitory activities were observed in fractions smaller than 5 kDa with IC50 being 0.85 and 1.78 mg/mL. Hence, the PPH and its small molecular fraction produced under proper Alcalase hydrolysis conditions have great potential to serve as a cost-effective anti-hypertensive ingredient for blood pressure management.

Digestion of whey peptide induces antioxidant and anti-inflammatory bioactivity on glial cells: Sequences identification and structural activity analysis

Whey derived peptides have shown potential activity improving brain function in pathological condition. However, there is little information about their mechanism of action on glial cells, which have important immune functions in brain. Astrocytes and microglia are essential in inflammatory and oxidative defense that take place in neurodegenerative disease. In this work we evaluate antioxidant and anti-inflammatory potential bioactivity of whey peptide in glial cells. Peptides were formed during simulated gastrointestinal digestion (Infogest protocol), and low molecular weight (<5kDA) peptides (WPHf) attenuated reactive oxygen species (ROS) production induced by hydrogen peroxide stimulus in both cells in dose-dependent manner. WPHf induced an increase in the antioxidant glutathione (GSH) content and prevented GSH reduction induced by lipopolysaccharides (LPS) stimulus in astrocytes cells in a cell specific form. An increase in cytokine mRNA expression (TNFα and IL6) and nitric oxide secretion induced by LPS was attenuated by WPHf pre-treatment in both cells. The inflammatory pathway was dependent on NFκB activation. Bioactive peptide ranking analysis showed positive correlation with hydrophobicity and negative correlation with high molecular weights. The sequence identification revealed 19 peptides cross-referred with bioactive database. Whey peptides were rich in leucine, valine and tyrosine in the C-terminal region and lysine in the N-terminal region. The anti-inflammatory and antioxidant potential of whey peptides were assessed in glia cells and its mechanisms of action were related, such as modulation of antioxidant enzymes and anti-inflammatory pathways. Features of the peptide structure, such as molecular size, hydrophobicity and types of amino acids present in the terminal region are associated to bioactivity.

Sacha Inchi (Plukenetia volubilis L.) Protein Hydrolysate as a New Ingredient of Functional Foods

Sacha inchi (Plukenetia volubilis L.) is an under-exploited crop with great potential due to its nutritional and medicinal characteristics. A Sacha inchi protein isolate (SII), obtained from defatted Sacha inchi flour (SIF), was hydrolyzed by Bioprotease LA 660 under specific conditions. The hydrolysates were characterized chemically, and their digestibility and antioxidant capacity were evaluated by in vitro cell-free experiments to select the hydrolysate with major antioxidant activity. Sacha inchi protein hydrolysate at 20 min (SIH20B) was selected, and the anti-inflammatory capacity was evaluated by RT-qPCR and ELISA techniques, using two different doses in monocytes THP-1 stimulated with lipopolysaccharide (LPS). The results obtained showed that the in vitro administration of SIH20B down-regulated the TNF-α gene and reduced the release of this cytokine, whereas the anti-inflammatory cytokines IL-10 and IL-4 were up-regulated in LPS-stimulated monocytes and co-administrated with SIH20B. The peptides contained in SIH20B were identified, and the 20 more relatively abundant peptides with a mass by 1 kDa were subjected to in silico analysis to hypothesize those that could be responsible for the bioactivity reported in the hydrolysate. From the identified peptides, the peptides AAGALKKFL and LGVKFKGGL, among others, are proposed as the most biologically actives. In conclusion, SIH20B is a novel, natural source of high-value-added biopeptides that could be used as an ingredient in formulations of food or nutraceutical compounds.

Lactobacillus brevis M2-Fermented Whey Protein Hydrolysate Increases Slow-Wave Sleep via GABAA Receptors in Rodent Models

In this study, we investigated the effects of whey protein hydrolysate (WPH) fermented with Lactobacillus brevis on sleep behavior and GABAergic mechanisms in rodent models. Fermentation converted the glutamate in WPH to high (3.15 ± 0.21 mg/mL) levels of γ-aminobutyric acid (GABA). Fermented WPH (WP-SF) enhanced sleep duration in mice by increasing GABA content in the brain. The increase in sleep duration induced by WP-SF resulted from an increase in delta wave activity during non-rapid eye movement sleep, and its sleep-promoting effect in a caffeine-induced insomnia model was characterized by an increase in delta waves. WP-SF increased GABAergic receptors at both mRNA and protein levels. Cotreatment with GABAA receptor antagonists abolished the sleep-promoting effects of WP-SF, indicating that WP-SF shares binding sites with antagonists on GABAA receptors. Collectively, WP-SF effectively increased sleep duration by enhancing delta wave activity through GABAergic activation; thus, it is suggested as a functional food-grade ingredient for promoting sleep.

Food-derived peptides unleashed: emerging roles as food additives beyond bioactivities

Innovating food additives stands as a cornerstone for the sustainable evolution of future food systems. Peptides derived from food proteins exhibit a rich array of physicochemical and biological attributes crucial for preserving the appearance, flavor, texture, and nutritional integrity of foods. Leveraging these peptides as raw materials holds great promise for the development of novel food additives. While numerous studies underscore the potential of peptides as food additives, existing reviews predominantly focus on their biotic applications, leaving a notable gap in the discourse around their abiotic functionalities, such as their physicochemical properties. Addressing this gap, this review offers a comprehensive survey of peptide-derived food additives in food systems, accentuating the application of peptides' abiotic properties. It furnishes a thorough exploration of the underlying mechanisms and diverse applications of peptide-derived food additives, while also delineating the challenges encountered and prospects for future applications. This well-time review will set the stage for a deeper understanding of peptide-derived food additives.

Chemical Behavior and Bioactive Properties of Spinorphin Conjugated to 5,5'-Dimethyl- and 5,5'-Diphenylhydantoin Analogs

The discovery of new peptides and their derivatives is an outcome of ongoing efforts to identify a peptide with significant biological activity for effective usage as a possible therapeutic agent. Spinorphin peptides have been documented to exhibit numerous applications and features. In this study, biologically active peptide derivatives based on novel peptide analogues of spinorphin conjugated with 5,5'-dimethyl (Dm) and 5,5'-diphenyl (Ph) hydantoin derivatives have been successfully synthesized and characterized. Scanning electron microscopy (SEM) and spectral methods such as UV-Vis, FT-IR (Fourier Transform Infrared Spectroscopy), CD (Circular Dichroism), and fluorimetry were used to characterize the microstructure of the resulting compounds. The results revealed changes in peptide morphology as a result of the restructuring of the aminoacidic sequences and aromatic bonds, which is related to the formation of intermolecular hydrogen bonds between tyrosyl groups and the hydantoin moiety. Electrochemical and fluorescence approaches were used to determine some physicochemical parameters related to the biological behavior of the compounds. The biological properties of the spinorphin derivatives were evaluated in vivo for anticonvulsant activity against the psychomotor seizures at different doses of the studied peptides. Both spinorphin analog peptides with Ph and Dm groups showed activity against all three phases of the seizure in the intravenous Pentylenetetrazole Seizure (ivPTZ) test. This suggests that hydantoin residues do not play a crucial role in the structure of spinorphin compounds and in determining the potency to raise the seizure threshold. On the other hand, analogs with a phenytoin residue are active against the drug-resistant epilepsy test (6-Hz test). In addition, bioactivity analyses revealed that the new peptide analogues have the potential to be used as antimicrobial and antioxidant compounds. These findings suggest promising avenues for further research that may lead to the development of alternative medicines or applications in various fields beyond epilepsy treatment.

Encapsulation of Tenebrio molitor Hydrolysate with DPP-IV Inhibitory Activity by Electrospraying and Spray-Drying

This study investigates the encapsulation of Tenebrio molitor hydrolysate exhibiting DPP-IV inhibitory activity by spray-drying and electrospraying techniques. First, we optimized the feed formulation and processing conditions required to obtain nano-microcapsules by electrospraying when using Arabic gum as an encapsulating agent and pullulan and Tween 20 as additives. The optimum formulation was also dried by spray-drying, where the removal of the additives was also assayed. Morphology analysis reveals that electrosprayed capsules have a smaller size (1.2 ± 0.5 µm vs. 12.4 ± 8.7 µm) and greater uniformity compared to those obtained by spray-drying. Regarding the surface nitrogen content and DPP-IV inhibitory activity, our results show no significant difference between the electrosprayed capsules and spray-dried capsules containing additives (IC50 of ~1.5 mg protein/mL). Therefore, it was concluded that adding additives during spray-drying allows for a similar encapsulation efficiency and reduced degradation during processing, as achieved by electrospraying technique but providing higher productivity. On the other hand, spray-dried capsules without additives displayed a higher surface nitrogen content percentage, which was mainly due to the absence of Tween 20 in the feed formulation. Consequently, these capsules presented a higher IC50 value (IC50 of 1.99 ± 0.03 mg protein/mL) due to the potential degradation of surface-exposed peptides.

De novo design of potential peptide analogs against the main protease of Omicron variant using in silico studies

SARS-CoV-2 and its variants are crossing the immunity barrier induced through vaccination. Recent Omicron sub-variants are highly transmissible and have a low mortality rate. Despite the low severity of Omicron variants, these new variants are known to cause acute post-infectious syndromes. Nowadays, novel strategies to develop new potential inhibitors for SARS-CoV-2 and other Omicron variants have gained prominence. For viral replication and survival the main protease of SARS-CoV-2 plays a vital role. Peptide-like inhibitors that mimic the substrate peptide have already proved to be effective in inhibiting the Mpro of SARS-CoV-2 variants. Our systematic canonical amino acid point mutation analysis on the native peptide has revealed various ways to improve the native peptide of the main protease. Multi mutation analysis has led us to identify and design potent peptide-analog inhibitors that act against the Mpro of the Omicron sub-variants. Our in-depth analysis of all-atom molecular dynamics studies has paved the way to characterize the atomistic behavior of Mpro in Omicron variants. Our goal is to develop potent peptide-analogs that could be therapeutically effective against Omicron and its sub-variants.

In silico and in vivo experiment of soymilk peptide (tetrapeptide - FFYY) for the treatment of hypertension

Enzyme-Treated Soymilk (ETS) was produced from Commercial Soymilk (CSM) with the treatment of proteinase PROTIN SD-NY10 (Bacillus amyloliquefaciens). Previously, we have isolated novel peptides from ETS but data related to isolated-peptides are scant. In this study, bio-informatics and in vivo analysis of isolated-peptides showed strong binding affinity to the active site of the Angiotensin Converting Enzyme (ACE). Among four peptides, tetrapeptide Phe-Phe-Tyr-Tyr (FFYY) showed strong binding affinity and inhibitory activity to the ACE-enzyme (binding affinity -9.5 Kcal/mol and inhibitory concentration of 1.9 µM respectively) as well as showed less toxicity compared to other peptides. The animal experiment revealed that single oral dose of FFYY (80 µg/kg body weight/day) effectively ameliorates the systolic, diastolic and mean blood pressure in the spontaneously hypertensive rat (SHR) model. Chronic oral administration of FFYY (80 µg/kg body weight/day for 3 weeks) reduced the systolic blood pressure elevation and ACE activity without any adverse side effects on the physiological and biological parameters of SHR. In conclusion, both in silico and in vivo experiments of soymilk-isolated FFYY peptide showed a promising option as a potential alternative for hypertension treatment without adverse side effects on SHR.

Characterization, Semirational Design for pH Robustness, and the Application in Bioactive Peptide Production of a X-Prolyl Dipeptidyl Aminopeptidase from Lactococcus lactis MY-3

PepXLcMY-3, an X-prolyl dipeptidyl aminopeptidase derived from Lactobacillus lactis MY-3, was screened and recombinantly expressed in Escherichia coli. The enzyme could exhibit about 40% activity within the pH range of 6.0-10. To further improve the pH robustness, site E396 located in the active pocket was discovered through alanine scanning. The mutant E396I displayed both developed activity and kcat/Km. The optimal pH of E396I shifted from 6.0 to 10 compared to WT, with the relative activity within the pH range of 6.0-10 significantly increased. The site K648 was then proposed by semirational design. The activity of mutant E396I/K648D reached 4.03 U/mg. The optimal pH was restored to 6.0, and the pH stability was further improved. E396I/K648D could totally hydrolyze β-casomorphin 7 within 30 min. The hydrolysate showed 64.5% inhibition on angiotensin I converting enzyme, which was more efficient than those produced by E396I and WT, 23.2 and 44.7%, respectively.

Characterisation and beneficial effects of a Lupinus angustifolius protein hydrolysate obtained by immobilisation of the enzyme alcalase®

Bioactive peptides have been considered potential components for the future functional foods and nutraceuticals generation. The enzymatic method of hydrolysis has several advantages compared to those of chemical hydrolysis and fermentation. Despite this fact, the high cost of natural and commercial proteases limits the commercialization of hydrolysates in the food and pharmacological industries. For this reason, more efficient and economically interesting techniques, such as the immobilisation of the enzyme, are gaining attention. In the present study, a new protein hydrolysate from Lupinus angustifolius was generated by enzymatic hydrolysis through the immobilisation of the enzyme alcalase® (imLPH). After the chemical and nutritional characterization of the imLPH, an in vivo study was carried out in order to evaluate the effect of 12 weeks treatment with imLPH on the plasmatic lipid profile and antioxidant status in western-diet-fed apolipoprotein E knockout mice. The immobilisation of alcalase® generated an imLPH with a degree of hydrolysis of 29.71 ± 2.11%. The imLPH was mainly composed of protein (82.50 ± 0.88%) with a high content of glycine/glutamine, arginine, and aspartic acid/asparagine. The imLPH-treatment reduced the amount of abdominal white adipose tissue, total plasma cholesterol, LDL-C, and triglycerides, as well as the cardiovascular risk indexes (CRI) -I, CRI-II, and atherogenic index of plasma. The imLPH-treated mice also showed an increase in the plasma antioxidant capacity. For the first time, this study demonstrates the beneficial in vivo effect of a lupin protein hydrolysate obtained with the alcalase® immobilised and points out this approach as a possible cost-effective solution at the expensive generation of the hydrolysate through the traditional batch conditions with soluble enzymes.

Production of chickpea protein hydrolysate at laboratory and pilot plant scales: Optimization using principal component analysis based on antioxidant activities

Chickpeas are a nutrient-rich source with optimal and high essential amino acid score. To evaluate its potential as a functional food ingredient, 36 chickpea protein hydrolysates were produced at the lab-scale using food-grade enzymes. Parameters including yields, protein content, hydrolysis degree, and antioxidant activities were employed to identify the most favourable conditions for scaling up production to a pilot plant level using a principal component analysis. The selected hydrolysate demonstrated commendable traits: a substantial content of essential amino acids and proteins at 67.71%, notable protein (73.12%) and weight (72.00%) yields, coupled with exceptional solubility exceeding 80%, and a noteworthy digestibility of 89.50%. Upon transition to pilot plant proportions, the hydrolysate retained its attenuated protein profile while exhibiting heightened antioxidant activities. Derived chickpea protein hydrolysates offer promise for innovative foods applications, impacting health and chronic disease prevention.

Hempseed protein-derived short- and medium-chain peptides and their multifunctional properties

Nowadays, the growing knowledge about the high nutritional value and potential functionality of hempseeds, the edible fruits of the Cannabis sativa L. plant, has sparked a surge in interest in exploring the worthwhile attributes of hempseed proteins and peptides. This trend aligns with the increasing popularity of hemp-based food, assuming a vital role in the global food chain. This chapter targets the nutritional and chemical composition of hempseed in terms of short- and medium-chain bioactive peptides. The analytical approaches for their characterization and multifunctional properties are summarized in detail. Moreover, the processing, functionality, and application of various hempseed protein products are discussed. In the final part of the chapter-for evaluating their propensity to be transported by intestinal cells-the transepithelial transport of peptides within hempseed protein hydrolysate is highlighted.

A comprehensive evaluation of milk protein molecular weight distribution based on exclusion chromatography dataset

Molecular weight is one of the main characteristic parameters of proteins, which is the basis for the functional properties of milk protein. This research aims at establishing molecular weight distribution pattern of milk protein based on exclusion chromatography. The method selected Na3PO4-Na2SO4 (0.1 M, pH 6.7) buffer as the mobile phase and detected at 220 nm by HPLC-UV. The protein molecular weight distributions were determined and compared for human milk, bovine milk, and infant formula. The proportion of macromolecular proteins is much higher in infant formula compared to human or bovine milk. The protein molecular weights of human and bovine milk are significantly different around 90, 20, 14, and 2 kDa. The results provide holistic compare of bovine milk, human milk, and infant formula through protein molecular distribution. The new evaluation indicators for protein will drive technological simulation of infant formula.

Food peptidomic analysis of bovine milk fermented by Lacticaseibacillus casei LBC 237: In silico prediction of bioactive peptides and anticancer potential

Bioactive peptides, which exhibited diverse biological activities such as anti-cancer, anti-inflammatory, bactericidal, antiviral, and quorum sensing properties, were considered promising alternative therapeutic agents. Sourced from various raw materials, particularly foods, these peptides garnered significant interest. In this context, the study focused on exploring bioactive peptides derived from bovine whole milk fermentation by Lacticaseibacillus casei LBC 237. Comprehensive peptidomic analysis and in silico predictions, with a specific emphasis on anti-cancer properties, were conducted. The study categorized peptides into BP-LBC, originating from the metabolism of L. casei LBC 237 and not matching any sequence in the Bos taurus database, and BP-MILK, matching a sequence in the Bos taurus database. Among the 143 identified peptides with potential biological activity, 33.56% were attributed to BP-LBC, while 66.43% originated from BP-MILK, demonstrating the important contribution of proteins in bovine milk in the generation of bioactive peptides. Hydrophobic peptides, enriched in Leucine, Lysine, and Proline, dominated both fractions, significantly influencing their functional properties. Pearson correlation analysis revealed inverse relationships between bioactive peptides, molecular weight, and anti-tumor activity in BP-MILK. The DGKVWEESLK peptide exhibited in silico activity against 10 different cancer cell lines. Studying the bioactive properties of peptides from familiar sources enhances the connection between food science and human health. In addition, in silico studies have been crucial in deepening our understanding of the bioactive potential of these peptides and their mode of action.

Bioinformatics and bioactive peptides from foods: Do they work together?

We live in the Big Data Era which affects many aspects of science, including research on bioactive peptides derived from foods, which during the last few decades have been a focus of interest for scientists. These two issues, i.e., the development of computer technologies and progress in the discovery of novel peptides with health-beneficial properties, are closely interrelated. This Chapter presents the example applications of bioinformatics for studying biopeptides, focusing on main aspects of peptide analysis as the starting point, including: (i) the role of peptide databases; (ii) aspects of bioactivity prediction; (iii) simulation of peptide release from proteins. Bioinformatics can also be used for predicting other features of peptides, including ADMET, QSAR, structure, and taste. To answer the question asked "bioinformatics and bioactive peptides from foods: do they work together?", currently it is almost impossible to find examples of peptide research with no bioinformatics involved. However, theoretical predictions are not equivalent to experimental work and always require critical scrutiny. The aspects of compatibility of in silico and in vitro results are also summarized herein.

Potential protein hydrolysates from the white and purple flower varieties of Orthosiphon aristatus leaves

This study was aimed to extract bioactive peptides from the white and purple flower varieties of Orthosiphon aristatus leaves. The herb is well known for its pharmacological importance, possibly attributed to its plant proteins. Phenol based extraction was used to extract plant proteins, and then hydrolysed by proteolytic enzymes such as trypsin (serine protease) and pepsin (aspartic protease). MS/MS analysis revealed that 145 and 125 proteins were detected from the white and purple flower varieties, respectively. Trypsin hydrolysates were showed to have a higher degree of hydrolysis (24-33%), resulting in higher antioxidant and antibacterial activities. The white flower of trypsin hydrolysates showed a higher radical scavenging activity which could be attributed to its higher content of stress proteins (19%). However, trypsin hydrolysates from the purple flower showed higher ferric reducing power and bacterial growth inhibition. The performance of hydrolysates was better than ampicillin in inhibiting Acinetobacter baumanni and Staphylococcus aureus.

Evaluation of physicochemical, textural, and microbial characteristics of probiotic soy cheese during storage: Generation and isolation of bioactive peptides

The purpose of this study was to ascertain how probiotic culture affected the physicochemical, textural, and microbiological characteristics of probiotic soy cheese during storage. Moreover, the release of bioactive peptides during fermentation and storage was examined. Each cheese sample was made from one of the probiotic cultures of Lactobacillus acidophilus, Lacticaseibacillus casei, and Bifidobacterium lactis. Peptide extracts were prepared from these samples and fractionated using reversed-phase high-performance liquid chromatography. The sample containing L. acidophilus had the highest dry matter and hardness. The samples with L. acidophilus and B. lactis, respectively, had the highest concentrations of lactic acid and acetic acid. During storage the acidity, dry matter, lactic acid, acetic acid, and hardness of the samples increased but the pH, springiness, and cohesiveness reduced (P < 0.05). All samples had a probiotic count greater than 107 CFU/g at the end of the storage. Antibacterial and antioxidant properties were found in the peptide fractions that were extracted from the samples. T2F4 (the fourth fraction separated from L. casei sample) had the greatest functional properties. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed the existence of peptide with a molecular mass of 5-10 kDa. Therefore, produced cheese is regarded as a suitable source of potentially bioactive peptides which can be utilized in food industry.

Unveiling the effects of shrimp hydrolysate as a dietary ingredient in healthy adult Beagle dogs

To be more sustainable, the pet food industry could increase the inclusion of animal byproducts from the human food chain and fish hydrolysates have been reported to benefit dogs' health. However, there is limited research on the impact of alternative marine hydrolysates in dog food. The current study evaluated the effects of including shrimp hydrolysate as a replacement for wheat gluten (experimental diet) in an extruded complete diet (control diet) on diet palatability, intake, digestibility, fecal characteristics and metabolites, oral volatile sulfur compounds (VSC), and coat quality in dogs. The palatability of diets was assessed in a 2-bowl test, conducted with 12 healthy adult Beagle dogs. No differences were observed in the first approach, first taste, or intake ratio. A randomized block design lasting 12 wk was performed with 12 dogs distributed into 6 blocks, according to sex and body weight; one dog from each block was randomly allocated to each diet. Fecal characteristics and metabolites were measured in weeks 0, 4, 8, and 12, VSC and coat quality in weeks 4, 8, and 12, and apparent total tract digestibility (ATTD) of nutrients and energy in week 12. The inclusion of shrimp hydrolysate did not affect intake, but increased fecal output (dry matter, DM, basis, P < 0.05). Fecal butyrate concentration was lower (P < 0.05) in dogs fed the experimental diet. The inclusion of shrimp hydrolysate did not affect ATTD of nutrients and energy, and VSC. Both diets promoted high coat quality. The experimental diet decreased gloss and general evaluation scores in week 4 (P < 0.05), but improved scale scores in weeks 4 and 12 (P < 0.05). Overall, the findings indicate the potential of including shrimp hydrolysate in diets for dogs, fostering a more sustainable industry.

Proteases immobilized on nanomaterials for biocatalytic, environmental and biomedical applications: Advantages and drawbacks

Proteases have gained significant scientific and industrial interest due to their unique biocatalytic characteristics and broad-spectrum applications in different industries. The development of robust nanobiocatalytic systems by attaching proteases onto various nanostructured materials as fascinating and novel nanocarriers has demonstrated exceptional biocatalytic performance, substantial stability, and ease of recyclability over multiple reaction cycles under different chemical and physical conditions. Proteases immobilized on nanocarriers may be much more resistant to denaturation caused by extreme temperatures or pH values, detergents, organic solvents, and other protein denaturants than free enzymes. Immobilized proteases may present a lower inhibition. The use of non-porous materials in the immobilization prevents diffusion and steric hindrances during the binding of the substrate to the active sites of enzymes compared to immobilization onto porous materials; when using very large or solid substrates, orientation of the enzyme must always be adequate. The advantages and problems of the immobilization of proteases on nanoparticles are discussed in this review. The continuous and batch reactor operations of nanocarrier-immobilized proteases have been successfully investigated for a variety of applications in the leather, detergent, biomedical, food, and pharmaceutical industries. Information about immobilized proteases on various nanocarriers and nanomaterials has been systematically compiled here. Furthermore, different industrial applications of immobilized proteases have also been highlighted in this review.

Natural Plant Materials as a Source of Neuroprotective Peptides

In many circumstances, some crucial elements of the neuronal defense system fail, slowly leading to neurodegenerative diseases. Activating this natural process by administering exogenous agents to counteract unfavourable changes seems promising. Therefore, looking for neuroprotective therapeutics, we have to focus on compounds that inhibit the primary mechanisms leading to neuronal injuries, e.g., apoptosis, excitotoxicity, oxidative stress, and inflammation. Among many compounds considered neuroprotective agents, protein hydrolysates and peptides derived from natural materials or their synthetic analogues are good candidates. They have several advantages, such as high selectivity and biological activity, a broad range of targets, and high safety profile. This review aims to provide biological activities, the mechanism of action and the functional properties of plant-derived protein hydrolysates and peptides. We focused on their significant role in human health by affecting the nervous system and having neuroprotective and brain-boosting properties, leading to memory and cognitive improving activities. We hope our observation may guide the evaluation of novel peptides with potential neuroprotective effects. Research into neuroprotective peptides may find application in different sectors as ingredients in functional foods or pharmaceuticals to improve human health and prevent diseases.

Fatty acid modification of casein bioactive peptides nano-assemblies, synthesis, characterization and anticarcinogenic effect

In this study, the nano-assemblies of bovine casein hydrolyzed peptides (HP) modified by fatty acids with various alkyl chain lengths (C8, C10, C12 and C14) were synthesized. The physicochemical properties of HP-C8-HP-C14 nano-assemblies were characterized using spectra, laser particle size analyzer, contact angle meter, scanning electron microscope (SEM) and cryo-transmission electron microscope (Cryo-TEM). HP-C8 and HP-C10 self-assembled into a hollow cube cage with an average size of ~500 nm, and the assembly of HP-C12 showed a flower-shaped morphology with more dispersed behavior, and droplet size was observed as ~20 nm. The in vitro cytotoxicity against human breast cancer cells MCF-7 was tested using CCK-8 assay and flow cytometry analysis. HP-C12 showed the highest cytotoxicity for MCF-7 cells with an inhibition rate of 66.03 % ± 0.35 % with an IC50 value of 7.4 μM among HP-Cn. HP-C8, HP-C10 and HP-C12 significantly affected on the migration, invasion and apoptosis of MCF-7 cells. The apoptosis mechanism may depend on the upregulation of anti-apoptotic protein Bcl-2 as well as pro-apoptotic proteins Bax and caspase-8. The dead MCF-7 cells were analyzed with UHPLC-MS/MS using untargeted metabolomics, revealing key metabolic pathways.

Emerging therapeutic options in the management of diabetes: recent trends, challenges and future directions

Diabetes is a serious health issue that causes a progressive dysregulation of carbohydrate metabolism due to insufficient insulin hormone, leading to consistently high blood glucose levels. According to the epidemiological data, the prevalence of diabetes has been increasing globally, affecting millions of individuals. It is a long-term condition that increases the risk of various diseases caused by damage to small and large blood vessels. There are two main subtypes of diabetes: type 1 and type 2, with type 2 being the most prevalent. Genetic and molecular studies have identified several genetic variants and metabolic pathways that contribute to the development and progression of diabetes. Current treatments include gene therapy, stem cell therapy, statin therapy, and other drugs. Moreover, recent advancements in therapeutics have also focused on developing novel drugs targeting these pathways, including incretin mimetics, SGLT2 inhibitors, and GLP-1 receptor agonists, which have shown promising results in improving glycemic control and reducing the risk of complications. However, these treatments are often expensive, inaccessible to patients in underdeveloped countries, and can have severe side effects. Peptides, such as glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), are being explored as a potential therapy for diabetes. These peptides are postprandial glucose-dependent pancreatic beta-cell insulin secretagogues and have received much attention as a possible treatment option. Despite these advances, diabetes remains a major health challenge, and further research is needed to develop effective treatments and prevent its complications. This review covers various aspects of diabetes, including epidemiology, genetic and molecular basis, and recent advancements in therapeutics including herbal and synthetic peptides.

Antioxidant peptides generated from chicken feet protein hydrolysates

BACKGROUND

As major industrial poultry by-products, chicken feet are considered as notable sources of several bioactive molecules. The current work covers the processing of chicken feet proteins as substrates to be hydrolysed by combinations of three commercial enzymes (Alcalase®, Flavourzyme® and Protana® Prime) during different hydrolysis periods and the evaluation of the identified peptides having antioxidant activity after simulated gastrointestinal digestion.

RESULTS

Enzymatic hydrolysis with Alcalase® and Protana® Prime combination for 4 h resulted in the highest activities. Reversed-phase high-performance liquid chromatographic separation of the purified hydrolysate yielded three active fractions that were further identified by nano-liquid chromatography-tandem mass spectrometry. The bioactivities of over 230 identified peptide sequences were estimated after simulated gastrointestinal digestion, and those peptides with the highest chance of exerting antioxidant activity were selected to be further synthesised and tested. In this sense, the synthesised dipeptides CF and GY showed the highest antioxidant capacity. CF presented IC50 values of 69.63 and 145.41 μmol L-1 in 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and oxygen radical absorbance capacity (ORAC) assays, respectively. In contrast, GY IC50 values were 15.27 and 10.06 μmol L-1 in ABTS and ORAC assays, respectively. Significant differences (P < 0.05) were registered between peptides in the same antioxidant assays.

CONCLUSION

Overall, the findings emphasised the favourable impact of enzymatic hydrolysis with the obtaining of antioxidant peptides from poultry by-products that could be evaluated as a safe and economical source to retard oxidation in food systems. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

A Quinoa Protein Hydrolysate Fractionated by Electrodialysis with Ultrafiltration Membranes Improves Maternal and Fetal Outcomes in a Mouse Model of Gestational Diabetes Mellitus

SCOPE

Quinoa intake exerts hypoglycemic and hypolipidemic effects in animals and humans. Although peptides from quinoa inhibit key enzymes involved in glucose homeostasis in vitro, their in vivo antidiabetic properties have not been investigated.

METHODS AND RESULTS

This study evaluated the effect of oral administration of a quinoa protein hydrolysate (QH) produced through enzymatic hydrolysis and fractionation by electrodialysis with ultrafiltration membrane (EDUF) (FQH) on the metabolic and pregnancy outcomes of Lepdb/+ pregnant mice, a preclinical model of gestational diabetes mellitus. The 4-week pregestational consumption of 2.5 mg mL-1 of QH in water prevented glucose intolerance and improves hepatic insulin signaling in dams, also reducing fetal weights. Sequencing and bioinformatic analyses of the defatted FQH (FQHD) identified 11 peptides 6-10 amino acids long that aligned with the quinoa proteome and exhibited putative anti-dipeptidyl peptidase-4 (DPP-IV) activity, confirmed in vitro in QH, FQH, and FDQH fractions. Peptides homologous to mouse and human proteins enriched for biological processes related to glucose metabolism are also identified.

CONCLUSION

Processing of quinoa protein may be used to develop a safe and effective nutritional intervention to control glucose intolerance during pregnancy. Further studies are required to confirm if this nutritional intervention is applicable to pregnant women.

Effect of Yeast-Derived Peptides on Skeletal Muscle Function and Exercise-Induced Fatigue in C2C12 Myotube Cells and ICR Mice

In our previous study, the antioxidant peptides (XHY69AP, AP-D, YPLP, and AGPL) were obtained from potential probiotic yeast (Yamadazyma triangularis XHY69), which was selected by our lab from dry-cured ham. This work aimed to explore the effects of yeast-derived peptides on skeletal muscle function and muscle fatigue. Results showed that yeast-derived peptides up-regulated slow-twitch fiber expression and down-regulated fast-twitch fiber expression in C2C12 cells (p < 0.05). The peptides improved mitochondrial membrane potential, adenosine triphosphate generation, and expression of cytochrome-relative genes, thus promoting mitochondrial function. Among these peptides, YPLP up-regulated the relative gene expression of the AMP-activated protein kinase (AMPK) pathway and activated AMPK by phosphorylation. Moreover, YPLP could prolong treadmill time, increase muscle and liver glycogen contents, reduce lactic acid and urea nitrogen contents, and alleviate muscle tissue injury in ICR exercise mice. These results demonstrate that yeast-derived peptides could change the muscle fiber composition, improve muscle function, and relieve muscle fatigue.