Search Results (122)

There is increasing interest in the health-promoting potential of plant protein-derived peptides for managing metabolic disorders. This study investigated the impact of pepsin digestion on pre-hydrolysed versus non-hydrolysed pea protein. Pepsin digestion resulted in a higher degree of hydrolysis in pre-hydrolysed samples (64%) compared to the non-hydrolysed samples (~40%). The pepsin hydrolysates from the pre-hydrolysed protein showed stronger inhibition of key metabolic enzymes compared to non-hydrolysed samples. After ultrafiltration to enrich peptides <10 kDa, inhibition of α-amylase, α-glucosidase, and ACE was markedly enhanced, achieving a maximum of 44.5%, 54% and 95%, respectively. Peptidomic analysis identified unique peptide sequences in the ultrafiltered pre-hydrolysed fraction, in silico prediction confirmed their bioactive potential. These findings demonstrate enhanced bioactivity in pre-hydrolysed pea protein samples following pepsin hydrolysis, which was most evident in the ultrafiltrated fractions. Overall, this approach highlights the relevance of enzymatic hydrolysis and peptide enrichment strategies in developing functional ingredients to support glucose regulation and cardiovascular health. Full article

As an emerging natural source of DPP-IV inhibition strategy, we report for the first time the use of Lithobates catesbeianus skin gelatin (LSG) as a novel source for DPP-IV inhibitory peptides in this study. Through enzymatic hydrolysis with multiple proteases, the papain-treated hydrolysate exhibited superior performance in hydrolysis degree, protein recovery, and DPP-IV inhibition, with 93.47% of peptides under 1 kDa. Subsequent separation and peptidomics analysis identified 13 previously unreported peptides. Molecular docking and in silico screening pinpointed four candidate peptides, i.e., LGPQR, RGFDQ, RGPVGP, and RLDDVT, which were then synthesized and functionally validated. Enzyme kinetic studies revealed that these peptides acted via competitive or mixed-type inhibition mechanisms. Notably, this study uncovered the bio-functional potential of amphibian-derived gelatin and provided a new strategy for natural DPP-IV inhibitor discovery through integrated enzymatic, computational, and biochemical approaches. This work pioneered the use of amphibian skin gelatin in antidiabetic peptide discovery and laid the foundation for its application in functional foods. Full article

Olive (Olea europaea) leaves, a by-product of olive oil production, represent a promising source of bioactive peptides. In this study, the peptidome of an olive leaf protein hydrolysate (OLPH) obtained via enzymatic hydrolysis with Alcalase was identified and analyzed for the first time. Liquid Chromatography coupled to Trapped Ion Mobility Spectrometry and Tandem Mass Spectrometry (LC-TIMS-MS/MS) analysis revealed over 7000 peptide sequences. Peptides with PeptideRanker scores above 0.79 were selected for in silico evaluation of antimicrobial potential, including physicochemical characterization and molecular docking. Several peptides—such as NYPAWGY, SSKGSLGGGF, QWDQGYF, and SGPAFNAGR—exhibited strong predicted antimicrobial potential, supported by favorable interactions with bacterial, viral, and fungal targets in docking simulations. Correlation analysis revealed that physicochemical features, such as net hydrogen, amphipathicity, and isoelectric point, were positively associated with predicted antimicrobial activity. These findings highlight the potential of olive leaf-derived peptides as natural antimicrobial agents and support the valorization of olive by-products as a sustainable source of functional ingredients for applications in food safety and health. Further experimental validation is needed to confirm the efficacy and mechanism of action of the identified peptides. Full article

Proteomics combined with peptidomics approaches were used to analyze the protein degradation and the release pattern of umami peptides in stewed chicken. The results showed that a total of 422 proteins were identified, of which 273 proteins consistently existed in samples stewed for 0–5 h. Myosin heavy chain exhibited the highest abundance (26.29–30.26%) throughout the stewing process. The proportion of proteins under 20 kDa increased progressively with the duration of stewing and reached 61% at 4–5 h of stewing. A total of 8018 peptides were detected in the soup samples, and 2323 umami peptides were identified using the prediction platforms iUmami-SCM, UMPred-FRL, Umami_YYDS, and TastePertides-DM. Umami peptides derived from titin (accession number A0A8V0ZZ81) were determined to be the most abundant, accounting for 24% of the total umami peptides, and Val534 and Lys33639 were the key N-terminal and C-terminal amino acids of these umami peptides. Abundance analysis showed that the umami peptides KK16 and SK18 ranked among the top 5 in the samples stewed for 0–5 h, and they were most abundant in the 3 h stewed samples. The results obtained will provide data support for promoting the industrialization of high-quality chicken soup products. Full article

Drought conditions impact plants at the morphological, physiological, and molecular levels. Plant tolerance to drought conditions is frequently associated with maintaining proteome stability, highlighting the significance of proteomic analysis in understanding the mechanisms underlying plant resilience. Here, we performed proteomic and peptidomic analysis of spring wheat (Triticum aestivum L.) under drought stress conditions. Using isobaric tags for relative and absolute quantitation (iTRAQ), we identified 497 and 157 differentially abundant protein (DAP) groups in leaves and roots, respectively. The upregulated DAP groups in leaves were primarily involved in stress responses, such as oxidative stress and heat response, whereas those in roots were associated with responses to water deprivation and sulfur compound metabolic processes. The analysis of the extracellular root peptidome revealed 2294 native peptides, including members of small secreted peptide (SSP) families. In the peptidomes of stress-induced plants, we identified 16 SSPs as well as peptides derived from proteins involved in cell wall catabolism, intercellular signaling, and stress response. These peptides represent potential candidates as regulators of drought responses. Our results help us to understand adaptation mechanisms and develop new agricultural technologies to increase productivity. Full article

Porcine intestinal mucosa hydrolysates (PIMHs) are by-products of heparin production obtained through a specific enzymatic hydrolysis process, which can theoretically generate bioactive peptides (BAPs). This study aimed to identify, characterize, and quantify BAPs in two Palbio products manufactured by Bioiberica S.A.U. (Palafolls, Spain), which are PIMH protein sources used for animal feed: Palbio^® HP (PHP) and Palbio^® 62 SP^® (P62). Using mass spectrometry (MS)-based peptidomics, we analyzed three samples from each product, fractionated based on molecular weight (<3 kDa, 3 to 10 kDa, and >10 kDa). The <3 kDa fraction was analyzed directly, while the other two fractions were enzymatically digested before MS analysis. The workflow identified 961 peptides in PHP and 1134 in P62. Subsequent bioinformatic analysis using public databases (APD2, StraPep, AHTPDB, and BIOPEP-UWM) led to the identification of six significant BAPs in both PHP and P62, with respective quantified amounts (pg peptide/μg sample): DAVEDLESVGK (0.1626, 0.1939), EGIPPDQQRLIFAGK (0.2637, 0.1852), TITLEVEPSDTIENVK (0.3594, 0.4327), TNVPRASVPDGFLS (1.4596, 0.1898), TNVPRASVPDGFLSEL (8.0500, 0.9224), and VHVVPDQLMAF (0.0310, 0.0054). The first three BAPs are related to antimicrobial activity, while the latter three are associated with cytokine/growth factor-like, antioxidant, and immunomodulatory activities. These bioactivities align with previously reported in vivo benefits observed in animal nutrition using Palbio products. Our findings demonstrate that PHP and P62 are valuable sources of BAPs, supporting their potential role in improving animal health and performance. Full article

Androgenetic alopecia (AGA), the most prevalent form of hair loss worldwide, faces significant therapeutic challenges due to high costs and limited efficacy of current interventions, necessitating safer and more effective solutions. Periplaneta americana (L.)-derived PA-011, endowed with anti-inflammatory and antioxidant properties, has demonstrated notable hair growth-promoting effects in AGA mouse models. This study employed LC-MS/MS, peptidomics, and network pharmacology to characterize PA-011’s chemical composition and predict its potential targets in AGA pathogenesis. Using Western blot and RT-qPCR, PA-011 intervention significantly inhibited inflammatory responses and oxidative stress levels in mouse skin tissues. Concurrently, PA-011 activated the proliferative potential of hair follicle stem cells, as demonstrated by upregulated expression of the cell proliferation marker Ki67, and activated the Wnt/β-catenin signaling pathway in DHT-induced AGA mice. Transcriptomic and metabolomic analyses revealed multi-target effects of PA-011, including modulation of PI3K-Akt/MAPK pathways, pentose phosphate metabolism, and amino acid biosynthesis. 16S rRNA sequencing and metagenomic analysis showed that AGA disrupts skin microbial homeostasis, while PA-011 intervention normalized the microbiota composition. Topical application of PA-011 promoted robust hair regrowth without detectable toxicity in safety assessments. This preclinical study establishes PA-011 as a promising candidate for AGA therapy, warranting further translational investigation. Full article

Glioblastoma multiforme (GBM) is a highly aggressive, treatment-resistant grade IV brain tumor with poor prognosis that grows rapidly and invades surrounding tissues, complicating surgery and frequently recurring. Although the crucial role of endogenous peptides has been highlighted for several tumors, the specific peptidomic profile of GBM remains unexplored to date. This study aimed to perform a preliminary characterization of the low molecular mass proteome fraction of Cavitron Ultrasonic Surgical Aspirator (CUSA) fluid collected from different tumor zones, i.e., the core and tumor periphery of newly diagnosed (ND) and recurrent (R) GBM. The samples, pooled by tumor type and collection zone, were centrifuged through molecular cut-off filter devices to collect the non-retained fraction of the proteome <10 kDa for direct full-length LC-MS analysis. A total of 40 and 24 peptides, fragments of 32 and 18 proteins, were marked as ND and R GBM COREs, respectively, while 132 peptides, fragments of 46 precursor proteins, were identified as common and included proteins which were cancer-related or involved in GBM pathophysiology. Besides providing a preliminary overview of the unexplored peptidome of GBM, this pilot study confirms peptidomics as a promising tool to discover potential GBM biomarkers in the perspective of clinical applications increasingly oriented towards a precision medicine approach. Data are available via ProteomeXchange with the identifier PXD060807. Full article

Bioactive peptides from black soldier fly larvae (BSFL) protein hydrolysates have gained attention for their health-promoting properties. Our previous study demonstrated the chemopreventive potential of BSFL hydrolysates prepared with Alcalase (ASBP-AH) in colon cancer cells; their in vivo efficacy has not been fully elucidated. This study evaluated the chemopreventive effects of ASBP-AH, processed by spray-drying (ASBP-AHS) or freeze-drying (ASBP-AHF), in a diethylnitrosamine (DEN) and 1,2-dimethylhydrazine (DMH)-induced rat model of early-stage colorectal carcinogenesis. Oral administration of ASBP-AHS or ASBP-AHF significantly reduced aberrant crypt foci (ACF) and downregulated PCNA, COX-2, and NF-κB expression, without affecting apoptosis. Furthermore, both treatments restored microbial species richness and shifted gut microbial diversity disrupted by carcinogen exposure. ASBP-AHS specifically enriched short-chain fatty acid (SCFA)-producing bacteria, while ASBP-AHF favored anti-inflammatory microbial signatures. Likewise, correlation analysis revealed positive associations between microbial changes and SCFA levels, particularly with ASBP-AHS. Peptidomic profiling identified identical peptides in both hydrolysates, including stable pyroglutamyl-containing sequences with potential anti-inflammatory and microbiota-modulating effects. These findings support the in vivo chemopreventive potential of ASBP-AH and its promise as a functional food ingredient for promoting gut health and reducing colorectal cancer risk. Full article

Goat caseins are highly polymorphic proteins that affect milk functional properties. In this study, an in silico approach was employed to analyze the influence of goat casein allelic variants on the quantity and bioactivity potential of peptides released after enzymatic hydrolysis. The reported protein sequences from the most frequent allelic variants in Capra hircus caseins (α-S1, β, α-S2, and κ-casein) were analyzed in the BIOPEP-UWM database to determine the frequency of occurrence of bioactive fragments from each casein. After specific hydrolysis with pepsin, trypsin, and chymotrypsin A, important differences in the peptide profile and bioactivity potential were observed within and between the casein allelic variants. The β-casein A and C alleles, α-S1-casein allele E, and α-S2-casein allele F presented the highest bioactivity potential, and some allele-specific peptides were also released, highlighting the impact of genotype on the predicted bioactivity. The inhibition of angiotensin-converting enzyme (ACE-I) and dipeptidyl peptidase IV (DPP-IV) activities was the most frequent bioactivity of the released peptides, suggesting possible antihypertensive and antidiabetic effects. Once confirmed by experimental studies, the use of goat casein genotyping could direct efforts to enhance the functional quality of goat milk. Full article

Ischemic stroke (IS) is a high-mortality, multi-complication cardiovascular disease. Reducing brain injury and promoting neuronal repair after IS onset remain important challenges for current treatments. Our team previously found that PAS840, an extract from Periplaneta americana (L.), protects nerve function; this study further uses LC-MS/MS and peptidomics to analyze PAS840’s components and network pharmacology to predict its ischemic stroke (IS) therapeutic targets. We then employed Transwell, a biochemical kit, real-time quantitative polymerase chain reaction (RT-qPCR), and transcriptomics to investigate PAS840’s effects on migration ability, oxidative stress levels, and cellular pathways in mouse microglial cells (BV-2) following oxygen–glucose deprivation/reoxygenation (OGD/R) injury. Finally, using Evans blue staining, immunohistochemical analysis, and RT-qPCR, we investigated PAS840’s effects on the blood–brain barrier, inflammation pathways, and neural function in a transient middle cerebral artery occlusion (tMCAO) rat model. PAS840 components target multiple IS pathways, effectively inhibit NF-κB/NLRP3/Caspase-1/IL-1β inflammasome pathway activation in BV-2 cells following OGD/R, reduce cellular oxidative stress, inflammation, and pyroptosis, and improve cell viability and migration ability. PAS840 decreases NF-κB/NLRP3/Caspase-1/IL-1β inflammasome pathway expression in tMCAO rat brains, reduces inflammation, activates BDNF/VGF/NGR1/Erbb4 neurotrophic factor and vascular endothelial growth factor pathways, enhances neuronal cell viability, and effectively protects and repairs the blood–brain barrier. Full article

Bioactive components of abalone and other marine organisms have attracted significant attention owing to their functional performance. The development of peptides with bioactivity like angiotensin-converting enzyme inhibitory (ACEi) and antioxidant properties is of great significance for chronic disease management and drug discovery. In this study, according to the issues of low utilization rate and bioactive content from the hydrolysate of abalone, single-factor and orthogonal experiments were designed to improve the utilization rate of abalone protein, and step hydrolysis with specific proteases was used to improve the overall biological activity of the hydrolysate. A total of 1937 peptide sequences were obtained from the highly bioactive components after separation and peptidomic analysis. Through virtual screening and molecular docking, 14 peptides exhibiting ACEi activity were identified and synthesized for experimental verification, with IC₅₀ values ranging from 0.05 to 0.54 mg/mL. Notably, nine of these peptides were powerful antioxidants. The developed step enzymatic hydrolysis and in silico screening-assisted preparation also provided a feasible and efficient method for exploring more bioactive peptides from diverse biomasses. Full article

There is a growing demand for natural and potent α-glucosidase inhibitors due to the rising prevalence of diabetes. In this study, newly identified α-glucosidase inhibitory peptides were identified from the tryptic hydrolysate of hemp seed proteins based on peptidomics and in silico analysis. A total of 424 peptides, primarily derived from four cupin-type-1 domain-containing proteins, were identified, and 13 ultimately were selected for validation based on their higher PeptideRanker scores, solubility, non-toxicity, and favorable ADMET properties. Molecular docking revealed that these 13 peptides primarily interacted with α-glucosidase via hydrogen bonding and hydrophobic interactions. Among them, three novel peptides—NPVSLPGR (−8.7 kcal/mol), LSAERGFLY (−8.5 kcal/mol), and PDDVLANAF (−8.4 kcal/mol)—demonstrated potent α-glucosidase inhibitory activity due to their lower binding energies than acarbose (−8.1 kcal/mol), the first approved α-glucosidase inhibitor for type 2 diabetes treatment. The molecular mechanism analysis revealed that the peptides NPVSLPGR and LSAERGFLY inhibited α-glucosidase by simultaneously blocking substrate entry through occupying the entrance of the active site gorge and preventing catalysis by binding to active sites. In contrast, the peptide PDDVLANAF primarily exerted inhibitory effects by occupying the entrance of the active site gorge. Molecular dynamics simulation validated the stability of the complexes and provided additional insights into the molecular mechanism determined through docking. These findings contribute essential knowledge for the advancement of natural α-glucosidase inhibitors and offer a promising approach to effectively manage diabetes. Full article

Sous vide, a cooking method that involves vacuum-sealed fish at low temperatures, yields a uniquely tender, easily flaked texture. Previous research on sous-vide tenderization has focused on thermal protein denaturation. On the other hand, the contribution of proteases, activated at low temperatures in fish meat, has been suggested. However, the details of protein degradation remain unclear. This study employed SDS-PAGE/immunoblot and peptidomic analysis of rainbow trout to assess proteolysis during sous-vide cooking. The results from SDS-PAGE and immunoblot analysis indicated reduced thermal aggregation of sarcoplasmic proteins and increased depolymerization of actin under low-temperature cooking conditions. A comparison of the peptidome showed that the proteolysis of myofibrillar proteins was accelerated during sous-vide cooking, with distinct proteases potentially activated at different cooking temperatures. Terminome analysis revealed the contribution of specific proteases at higher temperatures in rainbow trout. The results of this study demonstrate the thermal denaturation of sarcoplasmic proteins and proteolysis of myofibrillar proteins in rainbow trout meat during sous-vide cooking and its temperature dependence. The methodology in the present study could provide insights into the optimization of cooking conditions for different fish species, potentially leading to improved texture and quality of sous-vide products. Full article

Active peptides in mare milk have unique biological activities, but how the bioactive protein in mare’s milk changes under the influence of temperature has not been fully studied. Therefore, in this study, the differential expression of bioactive peptides potentially present in horse milk under different heat treatment conditions was investigated for the first time using peptidomic and bioinformatic techniques. We collected a total of 15 samples. In this study, we divided the samples into five groups, specifically, 65 °C, 30 min; 72 °C, 15 min; 83 °C; 10 min; 95 °C, 5 min; and an untreated group as a control, which involved four different temperature treatments, in order to understand changes in bioactive peptides and to identify the sequence of bioactive peptides. In the experiment, a total of 2341 active peptides were identified. The amino acid composition of the potential active peptides remained stable across different temperatures, but their abundance varied with temperature. In all, 23 peptides from 20 different proteins were identified, with the highest number of active peptides identified at 72 °C. Through database searches, we found that a majority of these peptides were within β-lactoglobulin and immunoglobulin domain proteins, which are known for their potential biological activities. These findings provide a theoretical foundation for the development of peptides with different bioactivities as potential functional foods. Full article