Search Results (160)

Collagen peptides (CPs) possess diverse biological activities, yet their oral efficacy is limited by gastrointestinal degradation and restricted systemic exposure of intact bioactive peptide species. Herein, a stable cholesterol-free nanoliposome system was developed using soybean phospholipids and stigmasterol through high-pressure microfluidization, followed by tangential flow filtration and spray drying to obtain a stable dry formulation. The optimized nanoliposomes exhibited a particle size below 100 nm, high peptide loading, excellent redispersibility, and remarkable physicochemical stability during refrigerated storage and under different pH and thermal conditions. During simulated gastrointestinal digestion, the stigmasterol-stabilized phospholipid bilayer effectively preserved encapsulated CPs throughout the gastric phase while facilitating peptide release under intestinal conditions. Oral administration in rats significantly enhanced collagen peptide bioavailability, increasing the plasma exposure (iAUC_{0–8 h}) of total hydroxyproline by 3.84-fold compared with free CPs. Peptide-bound hydroxyproline exposure increased 9.3-fold and accounted for approximately 94% of total absorbed hydroxyproline. UHPLC–HRMS analysis confirmed substantially enhanced systemic exposure of multiple characteristic hydroxyproline-containing dipeptides and tripeptides following nanoliposomal delivery. These findings indicate that stigmasterol-containing nanoliposomes improve the gastrointestinal stability and systemic delivery performance of collagen peptides, providing a promising strategy for enhancing the oral delivery potential of food-derived bioactive peptides. Full article

Broiler production keeps intensifying, and the environmental cost of the protein sources that feed it, principally soybean meal and fishmeal, has become harder to justify. Insect meal, derived chiefly from black soldier fly larvae (Hermetia illucens), yellow mealworm (Tenebrio molitor), and housefly larvae (Musca domestica), has emerged as a candidate able to address nutritional, immunological, and ecological goals at once. This review evaluates the evidence on the nutritional composition, digestibility, growth performance, immunomodulatory mechanisms, and gut health effects of insect meal in broiler diets, and weighs these findings against sustainability and economic considerations. The amino acid profile of insect meal is favorable, the fatty acid composition is distinctive, and bioactive compounds, chitin, antimicrobial peptides, and lauric acid among them, shape both innate and adaptive immune responses, reshape the gut microbiota, and reinforce mucosal integrity. Growth performance at partial replacement levels of soybean meal or fishmeal (5–15%) is broadly encouraging, although results differ across insect species, inclusion rate, and processing method. The immunomodulatory pathways involved, Toll-like receptor signaling, cytokine regulation, macrophage polarization, and immunoglobulin synthesis, converge on chitin acting simultaneously as a prebiotic substrate and an immune adjuvant. Critical knowledge gaps persist, including substantial variability in biological outcomes across insect species and rearing substrates, the absence of standardized processing protocols, limited mechanistic data from avian in vivo challenge models, and insufficient long-term validation under commercial production conditions. Cost and regulatory fragmentation across jurisdictions still constrain commercial uptake. Realizing the full potential of insect meal in sustainable broiler production will depend on multi-omics research, precision nutrition tools, and rigorous life-cycle assessment. Full article

This study investigated the effects of microwave puffing-induced soy protein structural modification on the dynamic changes in physicochemical properties and umami formation during soybean paste fermentation. The results indicated that optimal microwave puffing (400 W, 90 s) disrupts protein non-covalent bonds, depolymerizes protein aggregates, exposes the internal hydrophobic groups to enhance surface hydrophobicity, forms a loose porous structure, and creates favorable conditions for enzymatic hydrolysis during soybean paste fermentation. Conversely, excessive treatment (400 W, >90 s) induced protein re-aggregation and inhibited proteolysis, as confirmed by SEM. Furthermore, microwave puffing (400 W, 90 s) promoted Aspergillus oryzae growth and protease activity, and significantly improved physicochemical properties of soybean paste, including lower pH and higher contents of total acid (5.8%), amino acid nitrogen (11.8%), small peptides (13.3%), and reducing sugars (14.95%) (p < 0.05), plus a brighter, redder color. LC-MS/MS revealed microwave puffing (400 W, 90 s) reshaped the peptide profile of soybean paste, increasing the relative abundance of the umami amino acids (Glu, Asp) and sweet amino acid (Ala) and decreasing proportions of the bitter amino acids in the peptides. Sensory and electronic tongue analyses confirmed enhanced umami and weaker bitterness and saltiness. These findings demonstrate that microwave puffing (400 W, 90 s) effectively improves the quality and flavor characteristics of soybean paste, providing technical support for high-quality fermented soybean products. Full article

Liquid infant formula has garnered increasing attention due to its mild thermal processing and superior retention of bioactive nutrients. Within such matrices, the lipid source is a critical determinant of protein digestion behavior, yet its influence on peptide bioavailability and intestinal homeostasis remains undefined. Given that efficient peptide absorption is vital for the systemic delivery of bioactivity in infants, understanding the lipid–protein synergy is essential for formula optimization. Moreover, excessive oxidative stress is closely associated with impaired intestinal health and developmental disorders in infants, making the regulation of oxidative stress crucial for maintaining intestinal function. The present study evaluated the effects of three distinct lipid sources—soybean oil (SM), bovine milk fat (BM), and goat milk fat (GM)—on the physicochemical stability, proteolytic digestion, peptide release, intestinal absorption, and oxidative stress modulation of goat-milk-based infant formula. An integrated approach combining physicochemical characterization, in vitro simulated infant digestion, and a Caco-2 intestinal epithelial cell model was employed. we demonstrate that all three lipids (3% w/w) formed stable emulsions with uniform spherical structures and mean particle diameters of 117–300 nm, as visualized by laser confocal microscopy. Following in vitro simulation of infant gastrointestinal digestion, the SM group exhibited the most extensive protein hydrolysis, yielding the highest total peptide content (4.28 ± 0.10 mg/mL) and generated the highest number of peptides identified by LC-MS/MS (474 types). Bioinformatic analysis predicted that peptides from all groups possess potential antihypertensive, hypoglycemic, and immunomodulatory activities. The Caco-2 monolayer cell model demonstrated that although the GM group produced fewer identified peptide species than the SM group (365 types), it achieved significantly higher intestinal peptide absorption rate (55.34 ± 1.05%). Furthermore, the GM digests provided superior protection against H₂O₂-induced oxidative stress in Caco-2 cells, markedly reducing reactive oxygen species levels and suppressing the expression of pro-inflammatory cytokines TNF-α and IL-6. Collectively, these findings reveal that while soybean oil promotes more extensive proteolysis, the use of homologous goat milk lipid enhances peptide bioaccessibility and confers potential cytoprotective effects on intestinal epithelial cells, underscoring its potential as a preferred lipid source in infant formula formulations. Full article

Soybean peptides have been implicated in reducing body weight (BW); however, their efficacy for weight loss remains ambiguous. This study aimed to evaluate the effects of soybean peptides on BW outcomes via meta-analysis. To identify randomized controlled trials (RCTs) from January 2000 to June 2025, numerous databases (PubMed, Embase, Web of Science, and Cochrane Library) were searched comprehensively. Studies comparing the impact of different soybean peptide interventions on weight reduction were included. The weighted mean difference (WMD) and 95% confidence interval (CI) were synthesized. Surface under the cumulative ranking curve (SUCRA) determined the intervention rankings, and 18 RCTs met the inclusion criteria. Overall, soybean peptides significantly decreased BW (WMD = −1.96 g, 95% CI: −3.52, −0.40; p < 0.00001), BW gain (BWG), and body mass index (BMI). Subgroup analyses confirmed lowering of BW in both humans (WMD = −12.71 g, 95% CI: −30.42, 5.00; p < 0.00001) and mice (WMD = −1.73 g, 95% CI: −3.44, −0.03; p < 0.00001). The above results indicate that soy peptides contribute significantly to weight loss. Full article

Soybean meal (SBM) is a foundational protein source, but its industrial application is constrained by a complex matrix of anti-nutritional factors (ANFs). This review provides a critical synthesis of the biochemical transition from raw SBM to fermented SBM (FSBM), focusing on the synergistic mechanisms of fungal and bacterial co-fermentation. We identify that the efficacy of FSBM is primarily driven by the microbial proteolysis of glycinin into low-molecular-weight bioactive peptides (<1000 Da). These peptides serve as the primary drivers for improved intestinal morphology (increased villus height) and the modulation of the gut microbiota, providing a mechanistic basis for reported probiotic effects. Furthermore, we establish that the 5–10% improvement in the feed conversion ratio (FCR) documented for swines mathematically offsets the processing premium of fermentation. However, critical gaps remain in the standardization of solid-state fermentation (SSF) protocols, specifically regarding the selection of fungal (Aspergillus) and bacterial (Bacillus or Lactobacillus) strains, whose distinct metabolic pathways significantly diversify the functional profile of the resulting FSBM. Full article

Cottonseed meal (CSM) is a cost-effective protein source, but its application is limited by the toxicity of free gossypol. Traditional physical and chemical detoxification methods are costly, energy-intensive, and cause nutrient loss, while microbial fermentation-based biological detoxification is considered more sustainable than chemical or physical approaches. This study reports an alkaline protease from the marine strain Bacillus safensis DL12 isolated from Yellow Sea sediments. Following cloning of its encoding gene and heterologous expression, enzymatic characterization of the purified enzyme revealed optimal activity at pH 8.0 and 50 °C, with Fe²⁺, Cu²⁺, Ni²⁺, and dithiothreitol (DTT) significantly enhancing its activity. Substrate hydrolysis analysis using the purified enzyme on soybean meal, peanut meal, rapeseed meal, and cottonseed meal demonstrated that, compared to the control group, cottonseed meal hydrolysates exhibited a 55.6% relative increase in peptide content and a 41.5% relative improvement in the degree of hydrolysis (DH), indicating higher hydrolysis efficiency among the four substrates. Notably, when hydrolyzing cottonseed meal with purified enzyme versus crude enzyme preparation at equivalent activity, the purified enzyme effectively reduced free gossypol content by 70% compared to the control, achieving more efficient detoxification than the crude enzyme preparation and most reported microbial treatments. These results highlight the potential of B. safensis DL12 protease as a marine-derived enzyme, offering promising prospects for enhancing protein digestibility and addressing the long-standing challenge of gossypol toxicity in cottonseed meal utilization. Full article

Due to the lack of corn and soybean meal in animal feeding, rice bran meal (RBM) has been proposed as a beneficial substitute for these feedstocks’ ingredients. Its fermentation by using diverse microbes has been adopted as a beneficial technique. In this study, 18 five-month-old finishing pigs (castrated Duroc × Landrace × Large White) were assigned to three dietary groups with six replicates in each group, designated as the control (CON), unfermented RBM (RBM), and fermented RBM (FRBM) groups. RBM was fermented with a mixture of Lactobacillus johnsonii L63 and hydrolytic enzymes at 37 °C and pH 4.8 for 60 h. The results indicated that incorporating 30% fermented or unfermented rice bran meal into the diets of finishing pigs had no significant effect on growth performance. Regarding serum biochemical parameters, most indicators, including alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and triglycerides, showed no significant alterations. However, in both the unfermented and fermented rice bran meal groups, the concentrations of serum total protein, albumin, globulin, cholesterol, and blood urea nitrogen were significantly decreased (p < 0.05), whereas serum nitric oxide levels were significantly increased (p < 0.05). The FRBM group improved intestinal morphology and the digestibility of nutrients (crude protein, ether extract, crude fiber, and gross energy) by altering the mTORC1 pathway and upregulating the relative expression of amino acid and peptide transporter genes in the jejunum. However, the dry matter digestibility decreased compared to the CON group. The RBM group reduced nutrient digestibility, along with alterations in hepatic gene expression related to amino acid metabolism and transport. Therefore, fermented rice bran meal may offer a potential substitute feed ingredient for use in swine diets when conventional ingredients like corn and soybean meal are in short supply. Full article

This study used soybean meal as the substrate and systematically optimized its enzymatic hydrolysis through single-factor experiments and response surface methodology. A predictive model based on a Box–Behnken design was developed to improve protein hydrolysis efficiency and increase the yield of functional products. The optimal conditions were 1.45% enzyme addition, a reaction time of 62 h, a temperature of 36.5 °C, and a moisture content of 35%. Under these conditions, the small-peptide content increased 16.33-fold. Structural analyses showed that enzymatic treatment markedly disrupted the compact surface of soybean meal, converting it into a loose, porous matrix. In addition, enzymolysis altered the protein secondary structure from ordered α-helices and folded conformations to more disordered, flexible forms, thereby improving the molecular-weight distribution. Composition analyses showed an 114.2% increase in total free amino acids, including essential amino acids. Moreover, DPPH radical-scavenging activity increased from 18.37% to 57.99%. Overall, this study optimized the enzymatic hydrolysis conditions for soybean meal and provides valuable insights for the development of high-value protein-peptide products. Full article

In modern agriculture, small peptide fertilizers (SPFs) have emerged as a promising tool to enhance crop growth, yield, and stress resilience. However, the influence of raw materials and innovative preparation methods on SPF characteristics and agronomic performance remains underexplored. This study introduces instant catapult steam explosion (ICSE), a novel thermomechanical technology, for synthesizing SPFs from fish, soybean meal, and sheepskin. The molecular, chemical, and nutritional properties of the SPFs were then characterized using methods including gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), and HPLC/LC-MS. The research aims to characterize the molecular, chemical, and nutritional profiles of resulting SPFs and evaluate their effects on rice and rapeseed growth, yield, and nitrogen use efficiency (NUE). ICSE-generated SPFs exhibited distinct properties based on raw materials. Fish-derived SPF1 had a narrow molecular weight distribution, high small peptide content (573 mg g⁻¹), and free amino acids (0.478 mg g⁻¹), while sheepskin-derived SPF3 showed the lowest values (386 mg g⁻¹ and 0.366 mg g⁻¹, respectively). Fourier-transform infrared spectroscopy (FTIR) confirmed the presence of peptide bonds and functional groups, with variations in peak intensities reflecting differences in raw materials. Field trials revealed that SPF1 significantly improved rice and rapeseed growth parameters, including plant height, SPAD values, and flag leaf area, compared to controls. Yield increases of 10.36% (rice) and 11.74% (rapeseed) were observed for SPF1, alongside the highest NUE (42.3–43.4%). Soybean meal-derived SPF2 showed moderate performance, while SPF3 had minimal effects. These findings validate ICSE for sustainable SPF production and emphasize the importance of selecting raw materials to optimize fertilizer outcomes and enhance crop productivity. Full article

The study proposed a strategy using soybean protein hydrolysate (SPH) as the sole nitrogen source for promoting the proliferation and freeze-drying survival of Bifidobacterium breve and Bifidobacterium longum strains. High proportions of SPH replacing traditional nitrogen sources in MRSL significantly enhanced bacterial viable cell counts and OD₆₀₀ values. The small peptides (<3 kDa) and hydrophilic amino acid residues in SPH are considered to be the key factors for promoting bacterial growth. The exclusive use of SPH (100%-SPH) as the nitrogen source induced a morphological change in B. breve 1206 with the Y-shape transformation into smaller rod-shaped cells, while B. longum 070103 and 050101 became shorter rods. Cells with these morphological changes could more effectively maintain cell membrane integrity in an acidic condition and during the freeze-drying process. Consequently, MSPH improved cell viability and freeze-drying survival for B. breve 1206 in PBS and 10% skim milk compared to MRSL. It also significantly increased viable cell counts and the ability to survive freeze-drying for functional B. longum strains 070103 and 050101 in 10% skim milk, with survival rates increasing by 16.2% and 43.1%, respectively. These results showed the applicability of SPH in the industrial-scale cultivation of functional Bifidobacterium strains. It also provides new insights into soybean-derived nitrogen sources that can affect amino acid composition and bacterial morphology to enhance probiotic stability. This study supported the application of soybean peptides as the sole nitrogen source for producing high-viability probiotics and the potential prebiotic with health benefits. Full article

Soybean protein isolate (SPI) gel has been demonstrated to exhibit suboptimal stability and a coarse texture. Selective enzymatic hydrolysis modification has been demonstrated to effectively enhance the functional properties and structural stability of the protein. The objective of this study was to modify SPI using alkaline protease and papain. The impact of selective enzymatic hydrolysis on SPI was examined through the analysis of hydrolysis degree (DH), particle size, and protein purity. A systematic exploration was conducted in order to investigate the structural and quality characteristics of SPI gel. Indicators such as secondary structure changes, texture characteristics, water-holding capacity (WHC), rheology, and microstructure were analyzed. The findings indicate that when the DH of the SPI solution is 1%, its particle size is reduced relative to that when DH is 0.5%. The SDS-PAGE results indicated that alkaline protease could hydrolyze most of the 7S and 11S components in SPI into shorter peptides, while papain retained more of the 7S and 11S components and generated peptides with larger molecular weights. Fourier-transform infrared (FT-IR) spectral analysis indicated that following the process of enzymatic modification, the contents of α-helix and β-sheet in the secondary structure of SPI increased, while the contents of β-turns and random coils decreased. In the context of gel performance, it has been demonstrated that papain-modified SPI, attributable to its elevated content of macromolecular peptides, manifests superior WHC, hardness, springiness, cohesiveness, chewiness, storage modulus (G), and microstructure in comparison to alkaline protease-modified gel. Concurrently, the gel performance of papain modified SPI is significantly superior to that of unmodified SPI gel. This research provides a significant theoretical foundation and practical reference for promoting the efficient application of SPI in the domain of food processing. Full article

Comprehensive maternal nutritional interventions, particularly during late gestation, enhance perinatal outcomes and support long-term maternal-offspring health by modulating the microbiota. Fermented diets are recommended for inclusion in dietary guidelines during gestation, yet the specific metabolites after fermentation and their specific regulatory effects on gut microbiota during late gestation remain unclear. This study investigates the functional benefits of a fermented wheat bran–soybean meal–Broussonetia papyrifera mixed substrate (FMS) on the late-gestation gut microbiota using an in vitro fermentation model. The FMS was first fermented for 72 h with bacterial and enzymatic agents (2% v/v), then anaerobically incubated with fecal inocula from Jinhua pigs. Fermentation significantly enhanced nutritional profiles, increasing crude protein and amino acids while reducing fiber components (neutral detergent fiber, acid detergent fiber, and non-starch polysaccharide, p < 0.05). Metabolome analysis revealed a significant increase in the abundance of organic acids, amino acids, and short peptides in FMS, along with the enrichment of D-amino acid and sphingolipid pathways (p < 0.05). In addition, FMS significantly increased the abundance of Limosilactobacillus and Lactobacillus, as well as short-chain fatty acids production, compared to the unfermented group (p < 0.05). These findings demonstrate that fermentation pretreatment reduces fiber components, enhances flavor compounds and bioactive metabolites, thereby optimizing microbial utilization and increasing short-chain fatty acids production. Full article

A gastric–intestinal two-step enzymatic hydrolysis in vitro digestion simulation system was used to systematically investigate the digestion kinetics and amino acid release characteristics of five plant protein sources: soybean meal, rapeseed meal, corn DDGS, corn gluten meal, and corn germ meal. The results showed that in the gastric digestion phase (120 min), the protein hydrolysis degree of soybean meal was the highest (61.8%, p < 0.001), which was 4.4 times that of corn gluten meal (14.0%). In the intestinal digestion phase (240 min), the low-molecular-weight peptide release of corn gluten meal (31.2 mg/g) was significantly higher than that of corn DDGS (17.4 mg/g), showing a “weak in the stomach but strong in the intestine” characteristic. The “nutritional value equivalence” model constructed with soybean meal as the reference showed that the gastric digestion phase equivalence of rapeseed meal was only 32.2% (significantly lower than other materials), and the intestinal digestion phase equivalence of corn gluten meal was 62.9%. This study clarified the differences in digestion characteristics and key related indicators of different plant protein sources, providing quantitative references and scientific support for the food and feed industries to precisely select protein sources according to digestion phases and optimize the formula design. Full article

Bacillus subtilis is applied as a biofertilizer, biocontrol agent, and probiotic in agriculture, and is also used for industrial synthesis of proteins and peptides. These applications can be combined by using B. subtilis to synthesize plant health-promoting peptides in culture or to deliver them to roots via seed treatments. To facilitate the use of B. subtilis as a cell factory, we tested different media, temperatures, and growth phases to optimize ectopic expression of a Plant Elicitor Peptide from soybean (GmPEP3) that enhances seedling growth. Our results indicate that temperature, culture media, and growth phase have interactive effects, and that 30 °C and 2x YT media can enhance ectopic expression per cell compared to 37 °C or LB media in log phase bacteria. We also identified tradeoffs between cell growth and ectopic expression levels per cell, with the log phase favoring high expression per cell but the stationary phase yielding higher cell numbers and consequently higher expression levels per unit of growth media. In addition, to facilitate B. subtilis seed treatments, we compared retention of spores versus vegetative cells with and without carboxymethylcellulose (CMC) to improve the viability of B. subtilis seed treatments. Our results indicated that retention of viable bacteria on B. subtilis-treated seeds could be increased by ~40% by using the adhesive polymer CMC, and shelf life could be extended from 24 h to at least 3 months by using endospores rather than vegetative cells. For B. subtilis expressing GmPEP3, endospores also had comparable plant-growth-promoting activity as vegetative cells. This establishes the bioactivity of spores and illustrates the potential benefits of using B. subtilis to deliver heterologous peptides. These results provide valuable insights for deploying B. subtilis for crop health. Full article