Search Results (1,204)

β-Lytic protease (Blp) and protease L5 are enzymes from Lysobacter bacteria with distinct proteolytic and bacteriolytic activities. To characterize their substrate specificity, we employed liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis following hydrolysis of fractionated protein mixtures. Heatmaps and sequence logos revealed a pronounced specificity of Blp towards glycine and lysine residues, while L5 preferentially cleaved non-polar residues such as methionine, phenylalanine, and leucine. Notably, proline was frequently observed at the P2 position in L5 substrates. Comparative analysis with trypsin revealed that L5 generated significantly shorter peptides, whereas Blp produced fragments similar in length to tryptic peptides. These findings indicate different cleavage preferences and suggest potential applications for these enzymes in proteomic analysis. Full article

The infestation of boktor (Xystrocera festiva Pascoe) stem borer in Sengon (Falcataria falcata) tree plantations in Indonesia, especially in Java, has caused severe losses by damaging the stems, decreasing wood quality, and potentially leading to mortality. To digest the woods, the X. festiva larvae’s gut has at least two digestive enzymes, which are trypsin and α-amylase. Former studies have shown that F. falcata produces inhibitors of these two enzymes as part of its defense mechanisms. This research aimed to analyze trypsin inhibitor (TI) and α-amylase inhibitor (AAI) transcripts, as well as their expression, in X. festiva-infested and resistant F. falcata trees. We found 19 contigs encoding the TI gene and 29 contigs encoding AAI. The results were able to predict the sequence of the DNA that produced the TI and AAI transcriptomes, which proved that one gene could be expressed differently due to alternative splicing. The DEG analysis and RT-PCR confirmed that mostly the TI and AAI activity was heavily induced by the X. festiva larvae attacks. The expression of the TI gene was upregulated 0.78 times, while the AAI gene expression was upregulated 2.44 times in infested samples. The findings from this study are fundamental in understanding the mechanism of F. falcata resistance against X. festiva infestation and selecting the resistant trees. Full article

This study investigated the effects of dietary Rhodotorula mucilaginosa supplementation with different concentrations (0.0 g/kg, 0.1 g/kg, 1.0 g/kg, 10.0 g/kg) on red claw crayfish (Cherax quadricarinatus). Four groups were established: control group (CK, 0.0 g/kg), low-dose group (HL, 0.1 g/kg), medium-dose group (HM, 1.0 g/kg), and high-dose group (HH, 10.0 g/kg). The feeding trial lasted for 56 days. The results showed that, compared with the control group, all supplementation groups exhibited significantly reduced feed conversion ratios (p < 0.05). The HM and HH groups demonstrated significant increases in body length growth rate, specific growth rate, weight gain rate, hepatosomatic index, and survival rate (p < 0.05). All supplemented groups showed significantly enhanced trypsin and lipase activities in intestines and trypsin activity in the hepatopancreas (p < 0.05). The HM and HH groups exhibited elevated α-amylase activity in the hepatopancreas (p < 0.05). Compared with the control group, marine red yeast supplementation reduced colonization of potential pathogens while increasing probiotic abundance, effectively improving intestinal microbiota structure. The HM group significantly improved intestinal villus length, width, and muscular thickness (p < 0.05). All supplemented groups showed considerable upregulation of hepatopancreatic genes related to immunity (heat shock protein 70, down syndrome cell adhesion molecule, crustacean antibacterial peptide, serine proteinase inhibitors, crustacean hyperglycemic hormone, anti-lipopolysaccharide factor, lysozyme, and alkaline phosphatase) and antioxidant defense (superoxide dismutase, glutathione peroxidase, glutathione, and catalase) (p < 0.05). These findings indicate that R. mucilaginosa can significantly enhance digestive enzyme activity, maintain intestinal health, improve antioxidant and immune-related gene expression, and promote growth performance in red claw crayfish, with the HM group (1.0 g/kg R. mucilaginosa) showing optimal promotion effects. Full article

Moringa oleifera seeds are rich in protein, yet their potential as plant-based protein in food remains underutilized. This study evaluated the extraction efficiency, composition, and techno-functional properties of moringa seed protein isolate (MSPI) using enzyme-assisted (EAE), ultrasonic-assisted (UAE), and microwave-assisted extraction (MAE) methods, compared to conventional alkaline extraction (CE). EAE was performed with viscozyme (2%, pH 8, 50 °C, 2 h) and papain (1%, pH 7, 50 °C, 1 h), UAE at 40% amplitude (20 kHz, 20 min), and MAE at 800 W (50 °C, 90 s). All methods significantly improved extraction yield (14.60–30.08%), protein content (80.47–86.61%), solubility (40.78–60.09% at pH 10), and techno-functional properties over CE. However, MAE slightly reduced solubility. Phytates (0.83–0.49 g/100 g) and trypsin inhibitor activity significantly decreased (4.48–1.92 U/mg). In vitro protein digestibility improved (p < 0.05) across all samples (88.11–93.81%), with hydrolysis patterns supporting the enhanced digestibility. Structural modifications were indicated by altered surface hydrophobicity and thermal properties. SDS-PAGE showed consistent major protein bands at 17, 25, and 48–63 kDa, with EAE showing reduced intensity at ~63 kDa. While UAE and MAE achieved high protein yield and purity, EAE offered the best balance of functionality and digestibility, making it the most promising method for producing high-quality MSPI. These findings are relevant for guiding the selection of extraction methods for MSPI recovery for food applications. Full article

A soybean meal is a key protein source in human foods and animal feed, yet its digestibility is constrained by endogenous trypsin inhibitors (TIs). Thermal processing is the mainstream tool for TI inactivation, but high-intensity heat treatments increase energy consumption and can potentially denature proteins, diminishing nutritional quality. Reducing the thermal input while maintaining nutritional quality is, therefore, a critical challenge. One promising strategy is the use of soybean cultivars bred for low-TI expression, which may allow for milder processing. However, the performance of these low-TI cultivars under reduced heat conditions remains unstudied. This study treated soybean samples under four different temperatures (60, 80, 100, and 121 °C) for 10 min and investigated the impact of heat treatment on TI concentration, in vitro protein digestibility, and nutritional properties of meals from a conventional high-TI variety (Glenn) and a novel low-TI variety (VT Barrack). Results showed that heat treatment at 100 °C significantly improved protein digestibility and lower TI concentrations in both varieties. A negative correlation was observed between protein digestibility and TI concentration in both soybean varieties. At 100 °C, the low-TI variety achieved 81.4% protein digestibility with only 0.6 mg/g TIs, whereas the high-TI variety required 121 °C to achieve comparable protein digestibility and a TI reduction. These findings highlight that low-TI soybeans can lower the necessary thermal treatment to 100 °C to minimize TIs while simultaneously preserving protein quality and cutting energy demand, offering a practical, cost-effective approach to producing higher-quality soybean meals. Full article

The analysis of proteins in stool samples can significantly enhance the study of mammalian physiology and disease. In this study, we investigated the fecal proteome of clinically healthy dogs (n = 26) by a label-free proteomics approach to evaluate the impact of breed differences. The dogs were divided into two groups (n = 13 each) based on their breed, specifically Weimaraner and Dalmatian, the former known for their possible susceptibility to gastrointestinal disease. Quantitative and qualitative differences between the two experimental groups were identified based on analyses performed on pooled biological samples. The overall fecal proteome profile comprised 58 proteins, of which 37 were common, while comparative proteomics analysis detected 15 proteins with different abundances. Notably, the fecal proteome of Weimaraners showed an over-representation of proteins such as pantetheinase, which promotes inflammatory reactions; ferritin heavy chain and hemoglobin, possibly associated with gut ulceration and/or rectal bleeding typical of IBD; and anionic trypsin, implicated in inflammatory bowel disease. Notably, in Dalmatians, despite the absence of specific predispositions, some proteins associated with chronic enteropathy (e.g., carboxypeptidase B and serine protease 1) were also over-represented. Additionally, some proteins linked to breed variation included enzymes associated with “protein digestion and absorption” and “glycolysis and gluconeogenesis”. These findings suggest, for the first time, that the variable breed is a factor that may potentially influence the fecal proteome in dogs. Full article

This study examined the ultrasound pretreatment (UP) and simultaneous ultrasound (US) effects on the structural–functional features of collagen peptides in Chinemys reevesii skin collagen hydrolysates (CCHs) using a composite protease system (Trypsin: Alkaline protease, 1:1). Structural characterization revealed that UP induced the unfolding of collagen molecules, evidenced by reduced disulfide bond content and the concomitant increase in surface hydrophobicity. Consequently, ultrasound pretreatment-assisted enzymatic hydrolysis (UPH) significantly enhanced the yield of low-molecular-weight components (<0.18 kDa) and hydrophobic amino acids, which rose by 3.03% and 4.89% compared to the results of conventional enzymatic treatment (CE). UPH showed higher antioxidant activity than CE and WUH over CE and whole-process ultrasound-assisted hydrolysates (WUH). At 5 mg/mL, it displayed an ABTS radical scavenging rate of 87.59%, a DPPH scavenging rate of 53.37%, and the highest reducing power. However, WUH induced peptide reaggregation due to prolonged ultrasonication, thus exhibiting moderately lower antioxidant activity than UPH. These findings suggest that UP is an effective strategy to optimize the structure and composition of CCHs, outperforming both CE and WUH in facilitating the release of antioxidant peptides and improving antioxidant capacity. Full article

Alcohol Use Disorder (AUD) poses global health challenges, and causes hematological alterations such as macrocytosis and oxidative stress. Disruption of protein structures by alcohol and/or its metabolites may exacerbate AUDs; proteomics can elucidate the underlying biological mechanisms. This study examined the proteins differentially expressed in the cytosol and membrane fractions of erythrocytes obtained from 30 male patients with AUD, comparing them to samples from 15 age- and BMI-matched social drinkers (SDs) and 15 non-drinkers (control). The analysis aimed to identify the molecular differences related to alcohol consumption. The AUD patient subgrouping was based on mean corpuscular volume (MCV), with 16 individuals classified as having a normal MCV and 14 having a high MCV. Proteins were separated via two-dimensional(2D)-gel electrophoresis, digested with trypsin, and identified via Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (TOF) mass spectrometry (MALDI-TOF/TOF). Additionally, levels of malondialdehyde and 4-hydroxyalkenals (MDA + HAE), reduced glutathione (GSH), oxidized glutathione (GSSG), serum carbohydrate-deficient transferrin (%CDT), disialotransferrin (%DST), and sialic acid (SA) were analyzed. The results showed increased MDA + HAE and decreased total thiols in AUD patients, with GSSG elevated and the GSH/GSSG ratio reduced in the AUD MCV-high subgroup. Serum %CDT, %DST, and SA were significantly higher in AUD. Compared to the control profiles, the AUD group exhibited differential protein expression. Few proteins, such as bisphosphoglycerate mutase, were downregulated in AUD versus control and SD, as well as in the MCV-high AUD subgroup. Conversely, endoplasmin and gelsolin were upregulated in AUD relative to control. Cytoskeletal proteins, including spectrin-alpha chain, actin cytoplasmic 2, were overexpressed in the AUD group and MCV-high AUD subgroup. Several proteins, such as 14-3-3 isoforms, alpha-synuclein, translation initiation factors, heat shock proteins, and others, were upregulated in the MCV-high AUD subgroup. Under-expressed proteins in this subgroup include band 3 anion transport protein, bisphosphoglycerate mutase, tropomyosin alpha-3 chain, uroporphyrinogen decarboxylase, and WD repeat-containing protein 1. Our findings highlight the specific changes in protein expression associated with oxidative stress, cytoskeletal alterations, and metabolic dysregulation, specifically in AUD patients with an elevated MCV. Understanding these mechanisms is crucial for developing targeted interventions and identifying biomarkers of alcohol-induced cellular damage. The complex interplay between oxidative stress, membrane composition, and cellular function illustrates how chronic alcohol exposure affects cellular physiology. Full article

To systematically elucidate the chronological patterns of embryonic development and morphological changes in the larval and juvenile stages of Silurus glanis, and provide fundamental biological insights into this species, in this study, fertilized eggs were obtained through artificial spawning induction technology. After removing adhesiveness from fertilized eggs using trypsin, a detailed developmental study was conducted. The study systematically analyzed the chronological sequence of embryonic development and the morphological change patterns of larval and juvenile fish. The results showed the following: The fertilized eggs of S. glanis are yellow, spherical, and sticky, and the stickiness allows eggs to attach to spawning substrates, enhancing hatching success. The egg diameter after water absorption was (2.88 ± 0.13) mm. The embryonic development took 47 h and 55 min, with a total accumulated temperature of 1245.56 h degrees Celsius, the developmental process includes seven stages and twenty-six periods, namely the zygophase stage, cleavage stage, blastula stage, gastrula stage, neurula stage, organogenesis stage, and hatching stage. At a temperature of (26.0 ± 0.9) °C, the hatched individuals went through the pre-yolk sac larval stage, late larval stage, juvenile fry stage, and juvenile stage. In the pre-yolk sac larval stage, otoliths appeared in the bilateral otic vesicles, a pair of barbel primordia emerged under the mandible, a short and thin straight intestine formed in the abdominal cavity, and the oral fissure first appeared. In the late larval stage, the fin rays were initially formed, the intestine became thicker and longer, the oral fissure, anus, and cloaca were formed, and the larvae could float and start feeding on exogenous food. In the juvenile fry stage, the differentiation of various organs was basically complete, the nostrils became larger, and both the anal fin and caudal fin had dark black markings. In the juvenile stage, the maxillary barbels elongated, the mucus layer thickened on the body and back, the abdomen is light white, and it had the external morphological characteristics of an adult fish. By measuring and calculating the total length, body length, body height, and head length of S. glanis larvae and juveniles (0–40 days), the results showed that the growth characteristics conformed to the following fish growth formula: TL = 0.0141x² + 0.8096x + 8.2421 (R² = 0.9916), where x denotes days after hatching. This study has preliminarily mastered the chronological patterns of the embryonic development, growth, and formation of the morphological characteristics in larval and juvenile S. glanis, providing scientific data and laying a theoretical foundation for the division of early developmental stages, reproduction, hatching, and fry cultivation. Full article

Goats are important producers of meat, milk, hair, and leather. Early-weaned kids may encounter issues such as weaning stress and stress from high-density farming, which can hinder their growth and development. Therefore, exploring feed additives capable of alleviating stress in kids to enhance their growth performance is of particular importance. This experiment aims to investigate the effects of inulin on the growth performance, immune function, and intestinal health of weaned kids. Thirty healthy 60-day-old Leizhou black goat weaned kids with similar body weights (9.00 ± 0.05 kg) were selected and evenly divided into five groups by weight, with six kids in each group. The control group was fed the basal diet, while the AM HCl group received 0.05‰ aureomycin hydrochloride. The inulin groups were supplemented with 0.1%, 0.3%, and 0.5% inulin, respectively. By comparison, the results of the 0.3% inulin group in this experiment were most consistent with those of the AM HCl group, and the final weight of the kids was the highest. The 0.3% and 0.5% inulin groups had significantly enhanced immune-related indicator (such as sIgA, IgA, and IgG) concentrations and antioxidant activities (p < 0.05) in kids. Inulin significantly increased cecal total volatile fatty acids (TVFA) and the activities of jejunal α-amylase, chymotrypsin, and trypsin (p < 0.05); the activities of intestinal antioxidant enzymes, including GSH-PX, SOD, and T-AOC, were significantly increased (p < 0.05); and the intestinal anti-inflammatory factor IL-10 was significantly elevated (p < 0.05). Inulin significantly increased the mRNA expression levels of the tight junction protein genes TJP1 (ZO-1) and OCLN in the jejunum (p < 0.05). It also significantly upregulated the mRNA expression levels of anti-inflammatory factors TGF-β1 and IL-10 while significantly reducing the mRNA level of pro-inflammatory factor IL-6 in the jejunum (p < 0.05). Therefore, inulin enhanced the growth performance and antioxidant capacity of weaned kids, improved the body’s immune response, and reduced inflammatory responses. Specifically, when comparing the growth status, antioxidant enzyme activity, and tight junction protein mRNA level among the groups of kids, the 0.3% inulin supplementation yielded the best results in this experiment. Full article

Bacteriocins are ribosomal synthesized antimicrobial peptides produced by bacteria, but their low yields limit industrial applications as food preservatives. This study aimed to optimize the culture conditions of Pediococcus acidilactici CCFM18 and investigate the biological properties of the bacteriocin. The culture temperature, initial pH, and culture time significantly affected the growth of P. acidilactici CCFM18 and bacteriocin production. The optimal culture conditions determined through response surface methodology (RSM) were a culture temperature of 35 °C, an initial pH of 7.0, and a growth time of 16 h. Under these conditions, bacteriocin production reached 1454.61 AU/mL, representing a 1.8-fold increase compared to pre-optimization levels. Biological characterization revealed that the bacteriocin exhibited strong thermal stability (up to 100 °C for 30 min) and pH stability (pH 2–9), but was sensitive to proteolytic enzymes, including pepsin, trypsin, papain, and protease K. The bacteriocin demonstrated antimicrobial activity against both Gram-positive and Gram-negative bacteria, including Enterococcus faecalis and Escherichia coli. These findings provide a theoretical basis for the industrial production and application of the bacteriocin. Full article

This research assessed the efficacy of glutamate (Glu) supplementation to feed in counteracting growth restriction and intestinal stress-induced injury in juvenile groupers (Epinephelus coioides; initial weight 15.11 ± 0.03 g). The study comprised five isonitrogenous and iso-lipidic diets: a fish-meal-based (FM) diet, a soya-meal-based (SBM) diet, and SBM diets containing varying Glu levels of 1.0% (G-1), 2.0% (G-2), or 3.0% (G-3). The trial employed a randomized design with five treatment groups. Each group was housed in triplicate aquariums and received assigned diets for 56 consecutive days. Supplementation with Glu resulted in dose-dependent enhancements in weight gain, specific growth rate, serum high-density lipoprotein cholesterol, intestinal superoxide dismutase activity, digestive enzyme activity (trypsin, lipase, amylase), amino acid metabolic enzyme activity (glutaminase, GLS; glutamine synthetase), and intestinal mRNA levels of GLS, IL-10, and TGF-β1. Maximal values of the G-3 diet were restored to the levels of the FM diet (p > 0.05). Serum total cholesterol, intestinal total antioxidant capacity, and catalase activity followed a similar increasing trend with Glu level, attaining maxima in diet G-3, yet these values remained markedly lower than those of the FM diet (p < 0.05). Conversely, intestinal malondialdehyde content and mRNA levels of genes IL-8, IL-12, IL-1β, and TNF-α exhibited a significant dose-dependent decrease, reaching minimal levels in diet G-3 that were restored to the levels of the FM diet (p > 0.05). The results above demonstrate that Glu addition enhances nutritional status and intestinal structural integrity by augmenting antioxidant and digestive capacity and mitigating inflammatory responses, consequently enhancing growth performance and intestinal health. Full article

The growing consumer awareness of functional foods has increased interest in fermented plant-based products with enhanced nutritional and health-promoting properties. This comprehensive narrative literature review examines the potential of diverse raw materials for tempeh production beyond traditional soybeans, analysing their nutritional composition, bioactive compounds, and functional properties. A structured literature search was conducted on peer-reviewed publications up to July 2025, focusing on tempeh fermentation technology, chemical composition, and bioactive compounds from various substrates using recognised analytical methods according to Association of Official Analytical Collaboration (AOAC) standards. The analysis of over 25 different substrates revealed significant opportunities for enhancing tempeh’s nutritional profile through alternative raw materials including legumes, cereals, algae, seeds, and agricultural by-products. Several substrates demonstrated superior nutritional characteristics compared with traditional soybean tempeh, notably tarwi (Lupinus mutabilis) with exceptional protein content ((32–53% dry matter (DM)) and mung bean (Vigna radiata) exhibiting remarkably high polyphenol concentrations (137.53 mg gallic acid equivalents (GAE)/g DM). Fermentation with Rhizopus oligosporus consistently achieved substantial reductions in anti-nutritional factors (64–67% decrease in trypsin inhibitors, up to 65% reduction in phytates) while maintaining consistent antioxidant activities (39–70% 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition) across most variants. The diversity of bioactive compounds across different substrates demonstrates potential for developing targeted functional foods with specific health-promoting properties, supporting sustainable food system development through protein source diversification. Full article

Fermented wheat protein (FWP) has a high protein content and is beneficial to intestinal health, making it an ideal alternative to fishmeal (FM). This study evaluated the effects of replacing FM with FWP on growth performance, nutrient digestibility, and gut health in weaned piglets. A total of 144 weaned piglets (28 days old) were randomly divided into three dietary treatments with 48 piglets per treatment for a duration of 28 days. The treatments included a control diet containing 3% FM (CON group), a diet with 1.5% FM and 1.5% FWP (50% FWP replacement), and a diet with 3% FWP (100% FWP replacement). The results showed that replacing FM with FWP did not significantly affect average daily gain, average daily feed intake, or the feed conversion ratio but significantly reduced diarrhea rates (p < 0.01). The 50% and 100% FWP replacement significantly improved the digestibility of crude protein and acid detergent fiber, respectively (p < 0.05). The 100% FWP replacement significantly improved the activity of trypsin and chymotrypsin in the duodenum and jejunum (p < 0.05). Additionally, the 100% FWP replacement significantly enhanced serum total antioxidant capacity, glutathione peroxidase, and immunoglobulin A contents (p < 0.05). The 100% FWP replacement significantly increased villus height in the jejunum (p < 0.01). Moreover, the 100% FWP replacement significantly increased the expression of intestinal-barrier-related genes Zonula Occludens-1 and occludin (p < 0.01) and decreased the expression of inflammation-related genes (p < 0.01). Overall, FWP effectively reduces diarrhea rates, improves gut structure, enhances digestion, and boosts antioxidant and immune functions, particularly at a high replacement ratio (100%). Therefore, FWP can be considered an effective alternative to FM. Full article

Objective: Retinal capillary dropout, characterized by acellular capillaries or “ghost vessels,” is an early pathological sign of diabetic retinopathy (DR) that remains undetectable through standard clinical imaging techniques until visible morphological changes, such as microaneurysms or hemorrhages, occur. This study aims to develop a non-destructive artificial intelligence (AI)-based method using fluorescein angiography (FA) images to detect early-stage, silent retinal capillary dropout. Methods: We utilized 94 FA images and corresponding destructive retinal capillary density measurements obtained through retinal trypsin digestion from 51 Nile rats. Early capillary dropout was defined as having an acellular capillary density of ≥18 counts per mm². A DenseNet based deep learning model was trained to classify images into early capillary dropout or normal. A Bayesian framework incorporating diabetes duration was used to enhance model predictions. RNA sequencing was conducted on retinal vasculature to identify molecular markers associated with capillary early dropout. Results: The AI-based FA imaging model demonstrated an accuracy of 80.85%, sensitivity of 84.21%, specificity of 75.68%, and an AUC of 0.86. Integration of diabetes duration into a Bayesian predictive framework further improved the model’s performance (AUC = 0.90). Transcriptomic analysis identified 43 genes significantly upregulated in retinal tissues preceding capillary dropout. Notably, inflammatory markers such as Bcl2a1, Birc5, and Il20rb were among these genes, indicating that inflammation might play a critical role in early DR pathogenesis. Conclusions: This study demonstrates that AI-enhanced FA imaging can predict silent retinal capillary dropout before conventional clinical signs of DR emerge. Combining AI predictions with diabetes duration data significantly improves diagnostic performance. The identified gene markers further highlight inflammation as a potential driver in early DR, offering novel insights and potential therapeutic targets for preventing DR progression. Full article