Search Results (3,158)

Internet of things long range (IoT/LoRa) devices emit radiofrequency electromagnetic fields (RF-EMF), ensuring long-range, low-power communication, and their use in precision agriculture continuously expands. Thus, the interest in the impact of low-intensity but long-term EMF exposure on plants has increased. In this study, maize plants were exposed to 868 MHz, 10 mW EMF for the first 28 days of their development with soil-buried antennas. Plants were divided into three groups: Control, Sham-exposed, and EMF-exposed. Biological effects were followed on morphological, physiological, and biochemical levels every week. The plant height values were fitted to a Gompertz function modeling the growth. The results showed slightly faster early development of EMF-exposed plants in about 21 days. The relative dry-leaf biomass from EMF-affected plants was a bit higher than in the Control and Sham groups until day 21. Chlorophyll fluorescence analysis (JIP-test) indicated photosynthetic stability. Antioxidant enzyme activity, antioxidant capacity, content of malondialdehyde, hydrogen peroxide, and reducing sugars were measured, and principal component analysis was done for all parameters. Overall, the developmental stage accounts for most of the observed variations in the data rather than EMF exposure. The results suggest that under the tested conditions, IoT/LoRa-emitted EMF did not provoke adverse effects in maize and acted as a modest modulator of physiological functions. Full article

Plant-based symbiotic systems are often limited by poor storage stability and inconsistent biofunctional performance. This study evaluated the stability and functionality of a fermented blend based on sacha inchi (Plukenetia volubilis) oil press cake (SIC) and yacon (Smallanthus sonchifolius) flour (YF) as sources of protein and fructooligosaccharides (FOS), respectively, using two processing strategies: fermentation with Lactobacillus rhamnosus (T1) and combined enzymatic hydrolysis with Alcalase and fermentation with Lactobacillus plantarum (T2). Both treatments maintained viable cell counts (VCC) above probiotic thresholds (>10⁶ CFU mL⁻¹) during 28 days of storage at 4 °C, confirming their suitability as probiotic carriers. Notably, T2 significantly enhanced metabolic activity, as evidenced by higher organic acid production and increased soluble protein content due to Alcalase-mediated hydrolysis, which promoted the generation of bioactive peptides associated with improved antioxidant and antihypertensive activities. Biofunctional properties, including total phenolic content, antioxidant capacity (AC), and angiotensin-converting enzyme (ACE) inhibitory activity, remained stable throughout storage, while FOS degradation was minimal, confirming preservation of prebiotic functionality. LC–MS/MS Q-TOF analysis revealed a complex phenolic profile that was differentially modulated by lactic acid fermentation, with L. plantarum (T2) promoting extensive phenolic biotransformation and increased metabolite diversity, whereas L. rhamnosus (T1) largely preserved the original phenolic profile. These findings demonstrate that the synergistic interaction between enzymatic hydrolysis and L. plantarum fermentation promoted peptide release, intensified microbial metabolism, and enhanced phenolic biotransformation, thereby contributing to the superior functional properties observed in T2, while maintaining stable biofunctional characteristics throughout refrigerated storage in both treatments. Full article

Protein phosphatase PPM1A plays a critical role in cellular signaling by dephosphorylating key regulatory proteins. According to experimental data, the enzyme requires either Mn²⁺ or Mg²⁺ bound in the active center(s), hence its catalytic activity strongly depends on the chelated metal ions. In this study, the metal ion selectivity of PPM1A is investigated using DFT calculations on active site constructs of bi- and trinuclear metal centers and protein ligands from the first and second metal coordination shells. Binuclear Mn-Mn and trinuclear Mn-Mn-Mn sites show poor resistance to substitution by biogenic Fe²⁺ and Zn²⁺, with Gibbs energies of the Mn²⁺ → Fe²⁺/Zn²⁺ exchange being consistently negative in both the gas phase and condensed media. In contrast, Mg-Mg and Mg-Mg-Mg centers are substantially more robust, with a thermodynamically unfavorable Mg²⁺ → Fe²⁺/Zn²⁺ substitution—except in the case of the Mg-Mg-Zn complex. The primary factors governing this metal competition in the modeled structures are the nature of the competing cation and the solvation properties of its aqua complexes, while solvent exposure of the binding site and the number of metal cations in the catalytic center exert a comparatively minor effect. Overall, these findings demonstrate that Mg²⁺-loaded active sites offer considerably greater protection against biogenic metal displacement than their Mn²⁺ counterparts, thus shedding light on the metalloprotein stability and enzyme fidelity of PPM1A. Full article

The sustainable production of yellow catfish (Pelteobagrus fulvidraco) fry is critical for aquaculture, yet early developmental stages face high mortality and nutritional challenges. This study evaluated the effects of dietary supplementation with broken-cell wall P. rhodozyma on growth performance, organ development, enzyme activities, and gut microbiota composition in yellow catfish fry. Dietary supplementation with broken-cell wall P. rhodozyma significantly improved fry performance, increasing survival from 12% to 52%, promoting growth, enhancing intestinal and liver development, improving digestive enzyme activities, and modulating antioxidant-related physiological responses. It also elevated beneficial Muribaculum and reduced Streptococcus in the gut, promoting microbiota stability. These results demonstrate that P. rhodozyma supplementation not only improves early growth, organ maturation, stress resistance, and intestinal health but also effectively enhances overall fry health and development, thus supporting its use as a functional feed additive in aquaculture. Full article

Nitrogen (N) fertilization is a fundamental agronomic practice that governs crop productivity, yet its effects on the molecular composition and chemical stability of soil organic carbon (SOC) remain poorly understood, especially in cereal–legume intercropping systems. Traditional studies have focused on total SOC stocks rather than molecular-level changes, and the mechanistic pathway linking N addition to SOC functional group transformation remains unclear. This study addressed these critical gaps by investigating how graded N addition (0, 180, 270, and 360 kg N ha⁻¹) reshapes SOC chemistry in a subtropical soybean–maize intercropping system. Soil physicochemical properties, inorganic N pools, N-transformation enzyme activities (urease, nitrate reductase, and glutaminase), microbial biomass indices, labile organic carbon fractions (particulate, mineral-associated, and dissolved organic carbon), and SOC functional groups characterized by Fourier transform infrared (FTIR) spectroscopy were quantified across a two-year field experiment (2024–2025). Results showed that increasing N rates significantly elevated nitrate nitrogen (NO₃⁻-N) accumulation while depressing soil pH. Nitrogen-transformation enzymes, especially nitrate reductase and glutaminase, responded strongly and positively to the N gradient. Microbial biomass carbon (MBC) and nitrogen (MBN) increased with moderate N input but exhibited saturation or decline at 360 kg N ha⁻¹, accompanied by reduced microbial carbon use efficiency (CUE) and a lower MBC/MBN ratio. Among labile carbon fractions, dissolved organic carbon (DOC) was the most responsive pool, increasing markedly with N addition and correlating strongly with NO₃⁻-N. FTIR analysis revealed that N addition shifted SOC functional group composition toward chemically recalcitrant structures: the relative abundances of aromatic C=C and carbonyl C=O groups increased significantly, whereas labile C–O groups declined. Random forest modelling identified C=C, NO₃⁻-N, and DOC as the three most influential predictors of SOC chemical composition. Structural equation modelling (SEM) demonstrated a sequential mechanistic pathway: N fertilization increased NO₃⁻-N, which stimulated glutaminase activity and enhanced DOC, ultimately promoting C=C/C=O stabilization and explaining 91.3% of the variance in SOC aromaticity. These findings reveal that N addition does not merely augment SOC quantity but fundamentally transforms its molecular architecture toward greater chemical stability through a nitrate-mediated, enzyme–labile carbon coupling mechanism. This study provides a novel spectroscopic–mechanistic framework for understanding carbon–nitrogen interactions in intercropping agroecosystems and informs precision N management strategies aimed at simultaneous crop production and long-term soil carbon sequestration. Full article

Food-derived bioactive peptides have become a research hotspot in diabetes nutritional intervention due to their high safety, wide availability, and multi-target activities. This review addresses this by proposing a systems biology integration framework that defines these peptides as pleiotropic regulators of the gut microbiota-immune inflammation-metabolic signaling network, offering a novel systems-level perspective beyond previous reviews focused on single enzymes or pathways. The framework consists of three synergistic tiers. Tier 1 inhibits α-amylase, α-glucosidase or dipeptidyl peptidase-IV (DPP-IV) to control postprandial blood glucose. Tier 2 corrects insulin resistance by modulating phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt), activating nuclear factor erythroid 2-related factor 2 (Nrf2), and suppressing nuclear factor kappa-B (NF-κB). Tier 3 uses the gut as a hub to remotely coordinate metabolism via the gut–liver and gut–pancreas axes. The review also systematically summarizes the major sources and preparation methods of food-derived antidiabetic peptides, analyzes their advantages including multi-target network regulation, safety, and sustainability, as well as challenges such as oral bioavailability, insufficient clinical evidence, processing stability, and regulatory hurdles. Finally, it outlines future directions focusing on three actionable priorities: AI-assisted design, oral delivery systems, and high-quality clinical studies. This framework offers a new perspective for applying food-derived peptides in precision nutrition intervention for diabetes. Full article

Background: Cytochrome P450 3A4 (CYP3A4) is a key membrane-anchored drug-metabolizing enzyme. Its expression and purification in heterologous systems are severely hindered by low yield and detergent-induced structural inactivation. Although extracellular vesicles (EVs) provide an ideal natural lipid bilayer environment to stabilize membrane proteins, targeted loading remains challenging. The ESCRT and ALIX-binding region (EABR) of CEP55 can efficiently recruit core components of the endosomal sorting complex (ESCRT) to mediate membrane fission. Objectives: This study used the EABR motif to drive the targeted vesicular secretion of CYP3A4, thereby establishing a novel membrane protein engineering platform. Methods and Results: EABR was fused with fluorescent protein, confirming its specific mediation of vesicular secretion. Recombinant plasmids of EABR/CYP3A4 and its reverse mutant (R-EABR) were transfected into HEK293T cells. Western blot and midazolam-based metabolic assays showed that forward EABR significantly enhanced CYP3A4 expression and EV secretion, while R-EABR lost exocytosis function. EVs isolated by ultracentrifugation verified EABR’s role in recruiting ESCRT and improving CYP3A4 activity. Conclusions: Forward CEP55-EABR specifically and efficiently drives vesicular encapsulation of CYP3A4, enhancing its expression and secretion. This ESCRT-mediated strategy avoids destructive purification, provides a stable lipid-rich bioreactor for CYP3A4, and has great translational potential in high-throughput in vitro drug metabolism and screening platforms. Full article

Cysteine proteases (bromelain, ficin, and papain) are widely used in biotechnology and medicine, but their application is limited by rapid autolysis and oxidative inactivation. This study aimed to develop effective supports for these enzymes based on graft copolymers of sodium alginate and poly(N-vinylpyrrolidone) (SA-g-PVP) and to elucidate the structure–property relationships governing immobilization efficiency, catalytic activity, and storage stability. Copolymers were synthesized via radical solution polymerization under optimized conditions. Enzymes were immobilized by physical adsorption, and the resulting complexes were characterized by Fourier-transform infrared (FTIR) spectroscopy, protein content assays, proteolytic and amidase activity measurements, and molecular docking. The graft copolymer with a smaller particle size in solution provided a larger accessible surface area, leading to higher bromelain and papain loading. Ficin showed the opposite trend due to its unique surface amino acid composition. Immobilization dramatically increased storage stability: half-life values for bromelain, ficin, and papain reached up to 20, 14, and 14 days, respectively, compared to 1–3 days for the free enzymes. Molecular docking revealed that the dense polymer shell stabilizes the enzyme tertiary structure by forming multiple contacts with internal cavities and tunnels, thereby preventing autolysis and conformational unfolding. Collectively, these findings demonstrate that SA-g-PVP copolymers are promising, non-toxic supports for cysteine proteases, with ficin showing up to 100% activity recovery, making them suitable for food, cosmetic, and biomedical applications. Full article

In commercial pig production systems, early weaning imposes abrupt nutritional, environmental and social challenges before full gastrointestinal maturation has occurred, increasing susceptibility to post-weaning diarrhoea (PWD) and impaired growth performance. Although enterotoxigenic Escherichia coli (ETEC) is frequently implicated in PWD, pathogen presence alone does not adequately explain variation in disease expression among pigs and production systems. Increasing evidence indicates that gastrointestinal stability following weaning is determined by interactions among digestive capacity, substrate flow, microbial metabolism, epithelial integrity and host immune responses. In this review, substrate flow refers to the quantity, composition and regional distribution of undigested dietary and endogenous substrates moving through the gastrointestinal tract (GIT) and becoming available for microbial fermentation. The review proposes substrate flow as the central mechanistic interface linking digestive physiology with microbial metabolic activity during the post-weaning transition. Commercial weaning frequently occurs before complete adaptation to cereal- and plant-based diets has developed. Reduced feed intake, elevated gastric pH, incomplete pancreatic adaptation and reduced brush-border enzyme activity impair nutrient digestion during this transition, increasing nutrient overflow to the distal intestine. Under these conditions, microbial metabolism shifts from predominantly saccharolytic fermentation towards proteolytic pathways associated with production of ammonia, phenols, indoles and branched-chain fatty acids. These metabolites impair epithelial integrity, alter luminal conditions and favour proliferation of opportunistic bacteria. Conversely, effective digestion supports saccharolytic fermentation, short-chain fatty acid production, epithelial integrity and microbial stability. Microbial dysbiosis is therefore more accurately interpreted as a metabolic consequence of altered substrate availability and fermentation dynamics rather than solely as a compositional imbalance of bacterial taxa. By integrating digestive physiology, microbial ecology and nutritional management, the substrate-flow concept provides a mechanistic framework for development of more biologically coherent nutritional strategies aimed at improving gastrointestinal resilience and reducing antimicrobial reliance in modern pig production systems. Full article

To identify efficient cellulose-degrading microbes suitable for the animal intestinal environment and to address the low utilization of crude fiber in feed, eight cellulolytic strains were isolated from the ileum of Yangzhou geese. Among them, strain A2 showed the highest cellulolytic activity (D/d = 1.48) via the CMC (carboxymethyl cellulose) agar transparent zone method. Based on whole-genome-based identification, strain A2 was identified as Bacillus subtilis. Whole-genome sequencing revealed a circular chromosome of 4.02 Mb with a GC content of 43.72%, containing 4083 protein-coding sequences, of which 7.40% were involved in carbohydrate transport and metabolism. CAZyme annotation identified 167 carbohydrate-active enzyme genes, including 64 glycoside hydrolase genes, along with 60 hemicellulase and 3 lignin-degrading enzyme genes, forming a complete lignocellulose-degrading system. The cellulase from A2 exhibited optimal activity at 55 °C and pH 7.0, with good stability at 50–65 °C and pH 5–7, and was significantly inhibited by Cu²⁺, Mn²⁺, and Zn²⁺. Notably, its degradation efficiency toward microcrystalline cellulose reached 197% of that toward CMC. In conclusion, B. subtilis A2, with its excellent enzymatic properties and robust genetic foundation, is a promising candidate for developing feed enzymes and enhancing lignocellulose utilization. Full article

The replacement of fishmeal with plant protein is a key strategy for sustainable aquaculture, but reduced feed intake and digestive efficiency remain major constraints. This study evaluated the effects of dietary dimethyl-β-propiothetin (DMPT) supplementation on feed intake, digestive function, antioxidant capacity, and intestinal microbiota in narrow-clawed crayfish (Pontastacus leptodactylus) fed an all-plant protein diet. Three isonitrogenous and isolipidic diets were formulated: a plant protein diet (PPD), an animal protein diet (APD), and a PPD supplemented with 0.5% DMPT. After a 4-week feeding trial, results showed that PPD significantly reduced feed intake and digestive enzyme activities compared to APD, whereas DMPT supplementation restored feed intake to a level comparable to APD, maintained growth-related parameters at intermediate levels, and significantly enhanced α-amylase (AMS), lipase (LPS), and trypsin (TPS) activities. Additionally, DMPT markedly improved hepatopancreatic antioxidant capacity, as indicated by increased total antioxidant capacity (T-AOC), glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) levels, without affecting muscle composition or intestinal morphology. Microbiota analysis revealed that DMPT altered community structure, increased Bacillota abundance, and promoted microbial network stability. Overall, DMPT supplementation effectively mitigates the limitations of plant protein diets and supports the replacement of animal protein in crayfish aquafeeds. Full article

Flavonoids from Pinus koraiensis needle (PN) litterfall were efficiently recovered using an enzyme-assisted ultrasonic extraction (EAU) method optimized via response surface methodology (RSM). The optimal conditions (enzyme dosage 1.7%, ethanol concentration 70%, ultrasonic time 21 min, cellulase–pectinase ratio 1:3, liquid–solid ratio 40:1, enzymatic hydrolysis at 42.5 °C for 1 h, ultrasonic extraction at 50 °C and 150 W) yielded a total flavonoid content (TFC) of 17.08 mg rutin/g, which was significantly higher than that obtained via conventional extraction (CE). Scanning electron microscopy (SEM) confirmed that the treatment disrupted the cell wall, promoting flavonoid release. Ultra-performance liquid chromatography coupled with triple-quadrupole time-of-flight mass spectrometry (UPLC-Triple-TOF/MS) identified 60 flavonoids in the purified extract obtained under the optimal EAU conditions (OT group), including quercitrin, tiliroside, taxifolin, and procyanidin B2. Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) showed higher crystallinity but slightly reduced thermal stability for OT flavonoids. Notably, compared with the purified flavonoids obtained by CE (CK1 group), the OT group achieved a higher TFC and exhibited significantly better in vitro antioxidant activity (DPPH IC₅₀ = 71.82 μg/mL; ABTS IC₅₀ = 28.93 μg/mL) and in vitro carbohydrate-digesting-enzyme-inhibitory activity (α-glucosidase (α-GLU) IC₅₀ = 79.52 μg/mL; α-amylase (α-AMY) IC₅₀ = 793.9 μg/mL), with α-AMY inhibition being approximately 8.2-fold higher. These findings suggest that enzyme-assisted ultrasonic extraction is an efficient and reliable method for recovering flavonoids from PN and may provide a theoretical reference for the development and utilization of these flavonoids. Full article

The use of hydrolytic enzymes is one of the most promising methods for combating bacterial biofilms. However, the use of native enzymes is limited by the rapid loss of activity under unfavorable conditions. Immobilization of enzymes on carbon nanoparticles enhances their stability, allows for biocatalyst reuse, and creates a synergistic effect due to the intrinsic antimicrobial properties of the nanomaterials. The aim of this investigation was to create and comparatively analyze conjugates of acid and alkaline proteases with carboxylated multiwalled carbon nanotubes (MWCNTs-COOH) and to assess their effect on the formation and destruction of E. coli VKM B-3858D biofilms. The immobilization efficiency and kinetics of enzyme adsorption on the support were quantified by determining the protein concentration using the Bradford assay. The morphology and dispersion of the resulting conjugates were analyzed using atomic force microscopy (AFM). Protease activity was determined by a modified Anson method using the Folin–Ciocalteu reagent. Biofilm biomass was determined using crystal violet staining. The binding efficiency of the acid protease to MWCNTs-COOH was shown to reach 93%, which is significantly higher than that of the alkaline protease. The highest degree of immobilization was observed at a protein concentration of 117–338 μg/mL (10–20 mg/mL of the enzyme preparations). The interaction of the acid protease with the carbon nanoparticles increased dispersion, reducing the size of aggregates from ~1 μm to ~68 nm. As a result, acid protease conjugates with MWCNTs-COOH significantly reduced the biofilm biomass compared to both the enzyme-free control and the native enzyme. Alkaline protease, unlike the acid protease, destroys mature biofilms, and immobilization on MWCNTs-COOH enhances this ability. Native alkaline protease and acid protease conjugates with MWCNTs-COOH are effective in combating the biofilm formation of Gram-negative bacteria, while alkaline protease conjugates are suitable for disrupting mature biofilms. Full article

Carrot pomace (CP) represents a promising source of dietary fiber with potential applications in functional food systems. This study investigated the effects of enzymatic hydrolysis (Pectinex^® Ultra Tropical, Celluclast^® 1.5 L, and Viscozyme^® L) on the chemical composition, technological, and functional properties of CP. The untreated CP was characterized by a high total dietary fiber (TDF) content, predominated by insoluble dietary fiber (IDF), with a soluble dietary fiber (SDF)/IDF ratio of 1:1.6. Enzymatic treatment significantly reduced TDF and IDF (up to 54.1% and 58.5%, respectively) while increasing reducing sugars by 2.3–3.4-fold and changing the SDF/IDF ratio to 1:1.2–1.5. Technological properties were altered, with decreased oil-retention capacity and color intensity, whereas water-solubility index increased, and water-swelling capacity was enzyme-dependent. Emulsion stability was enhanced in enzymatically treated samples. Total phenolic content increased in the soluble fraction (up to 21.8%). Functional properties, including cholesterol-binding, sodium cholate-binding, and glucose-adsorption capacities, were significantly influenced by enzymatic modification and pH conditions (for cholesterol-binding capacity). Prebiotic activity varied depending on enzyme treatment, and Celluclast^®-modified CP demonstrated the highest prebiotic index, exceeding that of inulin for selected strains. Overall, enzymatic hydrolysis effectively modulated the structural and functional properties of CP, highlighting its potential as a value-added ingredient for the formulation of functional and prebiotic food products. Full article

To combat coastal wind erosion and develop sustainable stabilization technologies, a resource-efficient technique was developed based on the Enzyme-Induced Carbonate Precipitation (EICP) principle in the coastal regions of China. Utilizing seawater as a multi-ion source and discarded soybean hulls (Glycine max (L.) Merr.) as a crude urease source, this method is synergized with vegetation to form an environmentally friendly anti-erosion strategy. This study first explored the feasibility of soybean hull-derived urease, then analyzed the impacts of urease activity, reaction liquid volume, and seawater concentration on the germination and growth of Kalimeris indica. The results show that the biochemical mineralization process effectively sequesters soluble Ca²⁺ and Mg²⁺ from seawater into stable mineral phases, thereby mitigating salt-induced osmotic stress. Optimal plant growth was achieved at a seawater concentration of 0.2 mol·L⁻¹ and a liquid volume of 200 mL. Furthermore, the biocementation provided robust protection for initial plant growth, achieving an approximately 92.3% reduction in soil loss. Despite the presence of nitrogenous byproducts, the synergistic effect of EICP crusts and developing root systems ensures long-term wind erosion resistance and ecological integrity. This study highlights a functional transition from artificial mineralization to biological anchoring for sustainable coastal restoration. Full article