Search Results (81)

Rice bran, a nutrient-rich by-product of rice milling, is an underutilized resource in sustainable crop utilization. This study aimed to investigate the characteristics, total phenolic content, and antioxidant activities of rice bran protein hydrolysates (RBPHs) produced using proteases from Bacillus licheniformis (RBPH-B) and α-chymotrypsin (RBPH-C), along with their protein fractions (F1; >100 kDa, F2; 10–100 kDa, F3; 1–10 kDa, F4; <1 kDa). Molecular weight, color, surface hydrophobicity, secondary structure, total phenolic content, and antioxidant activities of the hydrolysates were assessed. Both enzymatic hydrolysis and ultrafiltration reduced molecular weight and surface hydrophobicity, enhanced lightness, and increased α-helix content. Among all samples, the <1 kDa peptide fraction derived from α-chymotrypsin hydrolysis (RBPH-C-F4) exhibited the strongest antioxidant activity, with the lowest EC₅₀ values for ABTS (0.94 mg/mL) and DPPH (210 µg/mL), as well as the highest inhibition of metal chelating activity (1.35 mmol EDTA/g sample) and linoleic peroxidation (90.62%). Enzymatic hydrolysis enhanced total phenolic content compared with native rice bran protein. These findings highlight the potential of rice bran-derived peptides as antioxidant candidates and indicate that further validation in food systems is required. Full article

Objective: This experiment aimed to explore the effects of water extract of Artemisia annua L. (WEAA) on growth performance, blood parameters, and intestinal-related indices in mutton sheep, so as to evaluate its potential as a natural growth promoter. Methods: The experiment was conducted using a completely randomized design. Thirty-two 3-month-old Dorper × Han mutton sheep were randomly assigned to 4 groups (n = 8). The control group was fed only the basal diet, while the other groups were fed the basal diet supplemented with, respectively, 500, 1000, and 1500 mg/kg WEAA. The adaptation period lasted 15 days, followed by a 60-day experimental period. Results: Results showed that dietary supplementation of WEAA significantly reduced average daily feed intake (ADFI) and feed-to-gain ratio (F:G) of mutton sheep, significantly improved the apparent digestibility of crude protein (CP) and phosphorus (P), and optimized blood biochemical indices, such as significantly increasing the concentrations of total protein (TP), albumin (ALB), high-density lipoprotein cholesterol (HDL-C), and glucose (GLU), while significantly decreasing blood urea nitrogen (BUN) level (p < 0.05). Additionally, WEAA significantly improved intestinal morphology by reducing the crypt depth (CD) of the duodenum, jejunum, and ileum, increasing jejunal villus height (VH), and elevating the villus-to-crypt ratio (VH/CD) across intestinal segments (p < 0.05). It also significantly enhanced the activity of intestinal digestive enzymes, including α-amylase and trypsin in the duodenum, lipase and chymotrypsin in the jejunum, and α-amylase and chymotrypsin in the ileum, with the 500 mg/kg and 1000 mg/kg WEAA groups reaching better activity (p < 0.05). Furthermore, WEAA supplementation significantly increased the counts of beneficial bacteria (Bifidobacteria and Lactobacilli) and decreased the count of harmful bacteria (Escherichia coli) in rectal fecal samples (p < 0.05). Notably, most of these beneficial effects were dosage-dependent, with overall optimal performance observed in the 1000 mg/kg WEAA group. Conclusion: In conclusion, supplementing the diet with 1000 mg/kg WEAA exerted significant positive effects on the feed efficiency, nutrient digestibility, and intestinal health status of mutton sheep. Full article

Background: The Fc region of immunoglobulin G (IgG) is a key target in therapeutic and analytical applications, such as antibody purification and site-specific bioconjugation. Although Protein A exhibits strong Fc-binding affinity, its large molecular weight and limited chemical flexibility pose challenges for use in compact or chemically defined systems. To address these limitations, we designed two α-helical peptides, SpA h1 and SpA h2, based on the Fc-binding helices of the Z34C domain from Staphylococcus aureus Protein A. Method: To enhance the structural stability and Fc-binding capability of these peptides, a lactam-based stapling strategy was employed by introducing lysine and glutamic acid residues at positions i and i + 4. Result: The resulting stapled peptides, (s)SpA h1 and (s)SpA h2, exhibited significantly improved α-helical content and IgG-binding performance, as demonstrated by circular dichroism (CD) spectroscopy and fluorescence-based IgG capture assays. Surface plasmon resonance (SPR) analysis confirmed specific, concentration-dependent interactions with the Fc region of human IgG, with (s)SpA h1 consistently showing the binding affinity and stability. Proteolytic resistance assays using α-chymotrypsin revealed that (s)SpA h1 maintained its structural integrity over time, exhibiting markedly enhanced resistance to enzymatic degradation compared to its linear counterpart. Furthermore, (s)SpA h1 exhibited strong Fc selectivity with minimal Fab affinity, confirming its suitability as a compact and Fc-specific binding ligand. Conclusions: These results confirm the successful design and development of structurally reinforced Fc-binding peptides that overcome the inherent limitations of short linear sequences through both high-affinity sequence optimization and lactam-based stapling. Among them, (s)SpA h1 demonstrates the most promising characteristics as a compact yet stable Fc-binding ligand, suitable for applications such as antibody purification and site-specific bioconjugation. Full article

Enterococci from raw goat milk were taxonomically allotted in the species Enterococcus faecalis using sequencing (16S rRNA and BLASTn analysis) with a percentage identity up to 99.91%. The virulence factor gene gelE was found in the strains EE/K3, EE/G3, and EE/G6. The agg gene was detected in the strain EE/G6, and the esp gene was detected in the strains EE/K5 and EE/G7. Each strain possessed at least one virulence factor gene. In the strain EE/G6, the gelE and esp genes were found. The strains EE/G6 and EE/G3 showed resistance to tetracycline and vancomycin. EE/G7 was resistant to vancomycin and gentamicin. All strains possessed low-grade biofilm-forming ability (0.1 < A570 ≤ 1.0). They possessed genes for biofilm formation (bopD, srt, and/or ace). They also produced esterase (20–40 nmo/L), esterase lipase, and α-chymotrypsin (10–40 nmoL). The values of acid phosphatase reached 20–40 nmoL. The strains EE/G3, EE/G6, and EE/G7 were observed to possess the most pathogenicity. However, all strains were susceptible to postbiotic active substances produced by two autochthonous lactococci, MK2/8 and MK1/3 (inhibitory activity up to 400 AU/mL). These postbiotic substances provide a new potential alternative to reducing contaminants in milk. Full article

This research explored the effects of supplementing taurine in a low-fishmeal diet on the growth, hepatic antioxidant capacity, muscle quality, intestinal health, and alleviation of inflammatory response of golden pompano (Trachinotus ovatus). Over an eight-week period, 300 juvenile fish (initial weight 9.4 ± 0.47 g) were randomly allocated into 12 net enclosures (1.0 × 1.0 × 1.5 m), with each treatment group comprising three replicate cages containing 25 specimens. The results demonstrated that an optimal taurine inclusion level of 1.0–1.5% significantly promoted growth, as evidenced by the increased weight gain rate (WGR) and specific growth rate (SGR). It also protected hepatic health by reducing alanine aminotransferase (ALT) activity and enhancing antioxidant capacity. Activation of the hepatic Nrf2/Keap-1/HO-1 signaling pathway increased the level of antioxidant gene expression, including catalase (CAT) and superoxide dismutase (SOD). In addition, the appropriate supplementation of taurine significantly down-regulated muscle hardness-related genes (cathepsin B (CatB) and cathepsin L (CatL)) and promoted the growth and differentiation of myoblasts, thus improving muscle quality. The chymotrypsin of fish fed the A25T10 diet was significantly higher than those in other groups (p < 0.05). The amylase (AMY) of fish fed the A25T15 diet was significantly higher than those in other groups (p < 0.05). The Chao1, Shannon, and Simpson of fish fed the A25T15 diet were significantly higher than those in other groups (p < 0.05). Proteobacteria were the most abundant in group A25T10. The relative abundance of Photobacterium rose in the A25RT10 group. In this study, taurine supplementation can down-regulate the expression of intestinal pro-inflammatory factors (interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-8 (IL-8)) and up-regulate the expression of anti-inflammatory factor interleukin-10 (IL-10), enhance intestinal immunity, and improve intestinal digestion and absorption. Therefore, the addition of 1–1.5% taurine to low-fishmeal feeds can improve the growth performance of golden pompano. Full article

The utilization of encapsulated biopharmaceuticals, including peptides and proteins, has grown substantially in recent years. In this study, the influence of aliphatic polyester physicochemical properties, specifically crystallinity and hydrophobicity, on the development of protein-loaded microparticles was investigated. A series of polyesters, namely amorphous PDLLA and semicrystalline PLLA, PCL, and PPDL, were synthesized via chemical and enzymatic ring-opening polymerization. Bovine serum albumin (BSA)-loaded microparticles were fabricated using a water-in-oil-in-water (w/o/w) double emulsion solvent evaporation method. The size of microparticles obtained was determined by scanning electron microscopy and dynamic light scattering methods. The enzymatic degradation of the polymer microparticles was assessed through incubation in a lipase-containing buffer solution. BSA and α-chymotrypsin (ACHT) were used as model proteins for the preparation of encapsulated polymer microspheres and comparison of their characteristics and properties. Protein encapsulation efficacy, release rate, and enzyme activity retained after encapsulation were evaluated and compared for selected aliphatic polyesters. The release profiles were processed with the use of various mathematical models to reveal the possible mechanism(s) of protein release. 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

Long-term storage may induce lipid oxidation in brown rice and impact its utilization in animal diets. One-day-old male Ross 308 broiler chickens (with an initial body weight of 20 g) were randomly divided into three groups: corn-based diet (Corn), fresh brown rice-based diet (BR1) and stored brown rice-based diet (BR6), with 8 replicates of 10 birds per pen, in a 42-day feeding trial. The results showed that lipid oxidation indexes increased and fatty acid composition changed significantly in BR6 (p < 0.05). The dietary replacement of corn with brown rice showed no effects on growth performance of broilers (p > 0.05). However, palmitic acid and oleic acid increased, and stearic acid, linoleic acid and docosadienoic acid decreased in the broiler breast muscle of the BR1 and BR6 groups (p < 0.05). Ileum antioxidant enzyme activities increased in the BR1 and BR6 groups compared to the Corn group (p < 0.05), and the activities of α-amylase, trypsin, chymotrypsin and lipase decreased in the BR6 group compared to the BR1 and Corn groups (p < 0.05). Also, compared to the BR1 group, the overall expression of metabolites involved in drug metabolism—cytochrome P450, GnRH secretion and the estrogen signaling pathway in broiler ileum were down-regulated in the BR6 group (p < 0.05). In conclusion, the lipid oxidation of stored brown rice decreased digestive enzyme activities and changed metabolic characteristics in the ileum of broilers. While replacing corn with brown rice did not affect broiler growth performance, it reduced the contents of unsaturated and essential fatty acids in breast muscle and enhanced the ileal antioxidant functions of broilers. Full article

High-fat diets are commonly used in fish farming due to their protein-sparing effect, contributing to reduced production costs. However, this practice may have adverse effects such as metabolic impairment and inflammation. These problems can be assessed in two ways: by developing functional diets or using food restriction, which leads to compensatory growth. The present study characterized digestion in gilthead sea bream fed a high-fat diet in the presence (HT) or absence (HF) of an olive oil polyphenol as an additive, hydroxytyrosol, under two different dietary regimes: feeding to satiation (ST) or at a 40% restriction (R). Digestive enzyme activities, specifically trypsin-like activities, were mainly upregulated by dietary treatment (HT). In contrast, restriction effects mainly appeared during digestion in the pyloric caeca, where a significant rise in chymotrypsin-like activities was detected. Moreover, those fish tended to have an increased relative intestinal length compared to those fish fed at a standard ration. Feed restriction enhanced the growth of γ-Proteobacteria in pyloric caeca and proximal intestinal regions, without altering their population in the distal intestine. Overall, it is suggested that hydroxytyrosol inclusion at a standard ration could improve digestion processes in gilthead sea bream fed high-fat diets under healthier conditions than without this additive. Full article

Objectives: To investigate the impact of α-chymotrypsin treatment on sperm recovery rate and total motile sperm count (TMC) in highly viscous semen for intrauterine insemination (IUI) and in vitro fertilization (IVF), particularly in cases of severely low sperm count. Methods: High viscosity was defined by the inability to form a thread exceeding 2 cm from a semen drop after 30 min of incubation at 37 °C with repeated pipetting. Semen samples were treated with 5 mg of α-chymotrypsin for 5–10 min at 37 °C and washed using a 90% gradient solution. A total of 35 patients were included, with comparisons made to the same patients’ prior untreated samples using paired t-tests. Severely low sperm count was classified as TMC below 10 million. Results: Treatment with α-chymotrypsin significantly improved TMC (22.2 million vs. 11.6 million, p = 0.0004) and motile sperm recovery rate (38.9% vs. 16.2%, p = 0.00002). In cases of severely low sperm count, α-chymotrypsin treatment resulted in a marked increase in recovery rate (43.0% vs. 10.0%, p = 0.02) and TMC (5.89 million vs. 1.21 million, p = 0.004). Fertilization using treated samples achieved an 87.8% success rate, with a 56.4% usable blastocyst rate, comparable to standard IVF outcomes (n = 9, average age = 34.9 years). Conclusions: α-chymotrypsin treatment significantly enhances sperm recovery and TMC in highly viscous semen, demonstrating particular efficacy in patients with severely low sperm counts without affecting fertilization or blastocyst rate in IVF. 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

This work aims to assess the intermolecular interaction of choline ionic liquids (ILs) (choline malonate ([Ch][Mal]), choline succinate ([Ch][Suc]), and choline valinate ([Ch][Val]) with two enzymes (lysozyme and α-chymotrypsin). We evaluated the state of the tertiary protein structure using circular dichroism (CD) spectrometry and quantified the binding parameters of the binding of the ionic liquids to the enzymes by fluorescence spectroscopy. The binding energies of the enzymes and the localization of ions on them were estimated using the molecular docking. We then analyzed the relationship between the enzymes’ thermostability and their tendency towards aggregation in the enzyme/ionic liquid systems. The obtained results were compared with previous data on albumins to identify similarities and differences between the behavior of enzymes and albumins in ionic liquid solutions. Despite the comparable values of the binding constants, the effect of ionic liquids on the thermostability of enzymes was the opposite of their effect on albumins. In addition, although these ionic liquids promoted aggregation in both enzymes and albumins, this effect was much more pronounced for albumins. Full article

Numerous studies have explored alternative protein sources to fishmeal (FM) to enhance fish diets, yet limited research exists on their effects on maturation. This study assessed the impact of replacing FM with soy protein concentrate (SPC) supplemented with lysine and methionine on growth and gonadal development in olive flounder (Paralichthys olivaceus). Three diets were tested: a control (Con) diet with 60% FM and two diets replacing FM with 25% (LF1) and 50% (LF2) SPC. Fish were fed to apparent satiation twice daily for 12 months. Growth performance and feed intake were not significantly different between groups. However, the gonadosomatic index varied with diet. Muscle composition and amino acid levels were similar across treatments, though n-3 fatty acids were higher in Con. Spermatogonia was increased, and spermatogenesis was impaired in SPC groups. At 12 months, oocytes in Con diets had absorbed yolk globules, whereas this was absent in SPC groups. Growth-related genes in the brain (growth hormones and insulin-like growth factor) were increased with higher SPC, while follicle-stimulating and luteinizing hormones decreased. Estrogen receptor α levels were elevated in SPC groups. Vitellogenin gene expression in gonads was highest in Con, while liver expression peaked in LF2. The expression of digestive enzymes, chymotrypsin2, and trypsin2 was highest in LF2, while lipase genes were lower. In summary, up to 50% FM replacement with SPC, with amino acid supplementation, supported growth performance and muscle composition without adverse effects on growth in olive flounder but influenced gonadal development. Full article

This study was conducted to investigate the impacts of the dietary addition of taurine and enzymatic cottonseed protein concentrate (ECPC) in low-fishmeal diet on the growth performance, plasma biochemical indices, hepatic antioxidant capacity, intestinal anti-inflammatory capacity, intestinal microflora, and muscle quality of golden pompano (Trachinotus ovatus). A total of three isonitrogenous diets were given to 225 golden pompanos (5.6 ± 0.14 g). They were randomly divided into nine cages (1.0 m × 1.0 m × 1.5 m; three cages per treatment) with equal stocking numbers of twenty-five fish per cage. The results indicated that the CSM-TC group significantly increased the growth performance of juvenile T. ovatus (p < 0.05). The results indicated that compared with other groups, the addition of 1% ECPC and 0.25% taurine has been found to enhance the WGR (weight gain rate), SGR (specific growth rate), and CF (condition factor). Compared with other groups, the relative expressions of GH, GHR1, GHR2, IGF1, IGF2, and MyoG were significantly higher in fish fed with CSM-TC. The results showed that CSM-TC significantly increased the activities of alkaline phosphatase, complement 3, and complement 4 enzymes (p < 0.05). The results showed that dietary CSM-TC increased the activities of hepatic superoxide dismutase and total antioxidant capacity enzymes. Compared with other groups, the hepatic relative expressions of Nrf2, HO-1, and GSH-Px were significantly higher in fish fed with CSM-TC. The results showed that dietary CSM-TC increased the activities of intestinal chymotrypsin, lipase, and α-amylase enzymes. A CSM-TC diet significantly increased the relative expressions of IL-10, ZO-1, Occludin, Claudin-3, and Claudin-15 (p < 0.05). The results showed that CSM-C significantly increased the index of Ace and Chao1 (p < 0.05). In conclusion, a high-fermented cottonseed meal diet can have detrimental effects on physiological health in golden pompano, while adding 1% ECPC and 0.25% taurine can improve hepatic and intestinal health via attenuating inflammation and oxidative stress. Full article

Marine natural products (MNPs) continue to be tested primarily in cellular toxicity assays, both mammalian and microbial, despite most being inactive at concentrations relevant to drug discovery. These MNPs become missed opportunities and represent a wasteful use of precious bioresources. The use of cheminformatics aligned with published bioactivity data can provide insights to direct the choice of bioassays for the evaluation of new MNPs. Cheminformatics analysis of MNPs found in MarinLit (n = 39,730) up to the end of 2023 highlighted indol-3-yl-glyoxylamides (IGAs, n = 24) as a group of MNPs with no reported bioactivities. However, a recent review of synthetic IGAs highlighted these scaffolds as privileged structures with several compounds under clinical evaluation. Herein, we report the synthesis of a library of 32 MNP-inspired brominated IGAs (25–56) using a simple one-pot, multistep method affording access to these diverse chemical scaffolds. Directed by a meta-analysis of the biological activities reported for marine indole alkaloids (MIAs) and synthetic IGAs, the brominated IGAs 25–56 were examined for their potential bioactivities against the Parkinson’s Disease amyloid protein alpha synuclein (α-syn), antiplasmodial activities against chloroquine-resistant (3D7) and sensitive (Dd2) parasite strains of Plasmodium falciparum, and inhibition of mammalian (chymotrypsin and elastase) and viral (SARS-CoV-2 3CL^pro) proteases. All of the synthetic IGAs tested exhibited binding affinity to the amyloid protein α-syn, while some showed inhibitory activities against P. falciparum, and the proteases, SARS-CoV-2 3CL^pro, and chymotrypsin. The cellular safety of the IGAs was examined against cancerous and non-cancerous human cell lines, with all of the compounds tested inactive, thereby validating cheminformatics and meta-analyses results. The findings presented herein expand our knowledge of marine IGA bioactive chemical space and advocate expanding the scope of biological assays routinely used to investigate NP bioactivities, specifically those more suitable for non-toxic compounds. By integrating cheminformatics tools and functional assays into NP biological testing workflows, we can aim to enhance the potential of NPs and their scaffolds for future drug discovery and development. Full article