Chemical and Biological Technologies in Agriculture最新文献

Background

The health of the hindgut in beef cattle plays a crucial role in their growth and overall health. Oregano essential oil (OEO) has gained attention as a potential alternative to antibiotics due to its various beneficial properties such as antibacterial and anti-inflammatory effects. However, its specific impacts on cecal health in beef cattle and its underlying mechanisms are yet to be fully understood. This study aimed to investigate the effects of OEO supplementation on basal immune status, intestinal barrier integrity-related gene expression, microbiota, and their metabolites in the cecum of beef cattle, thus to better understand its potential mechanism.

Results

Twenty-seven steers (initial body weigh 270.47 ± 16.26 kg) were randomly assigned to three groups with nine replicates each in a 390-day trial. Steers were fed with basal diet (CON), basal diet supplemented with 130 mg/d OEO (LOE), and basal diet with 260 mg/d OEO (HOE). Results showed that dietary HOE supplementation significantly increased the growth performance (average daily gain and final body weight) (P < 0.05). Compared to CON group, both LOE and HOE groups showed reduced levels of interleukin (IL)-1β, IL-2, and tumor necrosis factor α (TNF-α) (P < 0.05), while only HOE decreased IL-6 and increased IL-4 (P < 0.05). Moreover, HOE supplementation upregulated the intestinal tight junction proteins (ZO-1 and Claudin-1) gene expression (P < 0.05). The HOE group exhibited a significant increase in the relative abundances of cecal beneficial bacteria (e.g., Bacillus, Lactobacillus, and Lactococcus, P < 0.05). Furthermore, HOE supplementation increased the concentrations of butyrate in cecal short-chain fatty acids (P < 0.05).

Conclusion

HOE supplementation has the potential to regulate cecal barrier homeostasis, the microbiota and its derived metabolites, improve basal immune status, and ultimately benefit the health and performance of steers.

Graphical Abstract

Nitric oxide (NO) and salicylic acid (SA) are recognized for their ability to mitigate cadmium (Cd) stress, yet their roles in facilitating plant post-stress recovery after Cd exposure remain poorly understood. This study showed that birch seedlings exposed to 8 and 40 mg kg⁻¹ Cd for 15 and 30 days displayed significant dry weight reduction, elevated reactive nitrogen species (RNS) and reactive oxygen species (ROS) levels, and increased lupeol accumulation compared to controls. After 15 days of 40 mg kg⁻¹ Cd treatment, the exogenous supplement of the NO donor sodium nitroprusside (SNP) or SA effectively alleviated growth inhibition while reducing ROS levels and ROS/RNS ratios by 35.82–149.31% (SNP) and 33.12–147.53% (SA), concurrently enhancing lupeol content by 28.33–54.29% (SNP) and 19.59–80.01% (SA) and upregulating BpLUS2 (lupeol synthase) expression in the leaves, stems, and roots of the seedlings. Yeast expressing BpLUS2 (pYES2-BpLUS2) exhibited 32.89% higher lupeol production and 660.00% greater growth under Cd stress than controls. Furthermore, 1 and 3 μmol L⁻¹ exogenous lupeol increased fresh weight by 62.45% and 101.20% in Cd-stressed birch calli. Collectively, these findings demonstrate that SNP or SA supplementation promotes post-stress recovery in birch seedlings under Cd stress, highlighting the potential role of lupeol in mitigating Cd-induced stress.

Graphical Abstract

Serbian autochthonous cabbage cv. Futoški is highly susceptible to the plant pathogenic bacterium Xanthomonas campestris pv. campestris, the causal agent of black rot, leading to significant economic losses. This study aimed to isolate indigenous Bacillus spp. and Pseudomonas spp. strains with beneficial traits for biocontrol of black rot. From a total of 115 potential antagonistic strains, four (coded as P-FC 55, RD-FC 88, R-FC 102, And R-FC 114) identified as species Bacillus velezensis were selected as candidates based on strong in vitro antagonistic activity, both as whole cultures and cell-free supernatants, against the most virulent X. campestris pv. campestris strain (XcFC 231) identified in this study. No statistically significant differences were observed between the efficacy of whole cultures and supernatants of biocontrol candidates. Preventive inoculation approaches (seed and foliar) of biocontrol candidates consistently outperformed curative treatments across all strains, highlighting their potential as preferred application strategies. The most effective B. velezensis strain was RD-FC 88, applied in the form of a whole culture during preventive foliar application, achieving 93.86% disease suppression, surpassing copper oxychloride (89.26%) under the same conditions. Chemical profiling (GC/MS and UHPLC–QToF MS) of ethyl acetate extracts revealed the presence of a wide range of antimicrobial organic compounds (e.g., 2,3-butanediol, urea, succinic acid, thymine, phenylalanine, 9H-purin-6-ol) and lipopeptides (surfactins C₁₂–C₁₇), which may be contributing factors to the biocontrol activity of the strains. Next to the surfactins, molecular screening for the presence of genes encoding the production of lipopeptides with antimicrobial activity indicated the potential of strains to produce bacillomycin D and iturins (except R-FC 114) under certain growing conditions. Preventive application (seed and foliar) of biocontrol candidate strains led to an increase in epidermal flavonoid and chlorophyll content, while the opposite trend was observed in curative treatments. The results of this study highlight the strong potential of the B. velezensis strains P-FC 55, RD-FC 88, R-FC 102, And R-FC 114 for controlling black rot disease on the cabbage cv. Futoški, with possible broader applicability to other cabbage cultivars and Brassicaceae crops.

Graphical Abstract

Ammonia (NH₃ ) and nitrous oxide (N₂O) emitted from the pig slurry (PS)-applied soil lead not only to the risk of environmental pollution, but also to the loss of plant nutritional nitrogen (N). This study aimed to compare the effectiveness of zeolite and rice husk biochar (RHB) in mitigating the N losses via NH₃ and N₂O emissions from PS-amended soils, and N use efficiency (NUE) for vegetative growth of oilseed rape (Brassica napus L.). Both zeolite and RHB application significantly reduced NH₃ and N₂O emissions from the PS-applied soil and improved the NUE for the vegetative growth. When compared the effectiveness of two materials, RHB application has more positive effectiveness in soil pH buffering, urease activity, organic acid content and NH₄⁺ content in soil throughout the experimental period, resulting in a higher mitigation of NH₃ and N₂O emissions as well as NUE for dry matter (DM) and crude protein (CP) production. The enhanced NH₄⁺ content in soil closely related to the reduction of NH₃ and N₂O emissions, and with improved NUE for DM and CP production. A superior performance of RHB relative to zeolite is attributed mainly to a stronger capacity of NH₄⁺ adsorption by higher oxygen-containing functional groups on its surface, and in part to the supply of bioavailable carbon derived from RHB leading to an increase in urease activity and soil organic acid content. Therefore, RHB can be considered a more promising amendment than zeolite for simultaneously mitigating gaseous N losses and enhancing NUE in oilseed rape cultivation.

Graphical abstract

Background

Hydrogen peroxide and hypochlorous acid are reactive oxygen species that naturally occur in biological systems; the oxidation products of biological molecules, such as carotenoids, formed by these oxidants are found in foods and living organisms. This study aims to identify these metabolite products and propose the degradation mechanism based on the identified product structures and the obtained kinetic data. To protect carotenes from oxidation and improve their use as food additives and pharmaceuticals, carrot carotenoids were encapsulated in a chitosan-TPP copolymer.

Results

The results revealed that the main carotene oxidation product from H₂O₂ and HOCl was apo-13-carotenone-5,6-epoxide; LC–MS/MS also detected additional products for the first time. The kinetics study indicated that oxidation follows first-order kinetics in carotene and second-order kinetics in H2O2, with epoxidation of the ring double bonds and cleavage of the 13-double bond forming the major product, while cleavage of the single bond C10’–C11 resulted in the minor product, β-apo-12ʹ-carotenone-5,6-epoxide; proposed mechanisms were outlined. To protect carotenoids from oxidation, a chitosan-TPP complex was prepared and characterized. While free carotene stability decreased to 63% after 120 min and 34% after 30 min under H₂O₂ and HOCl treatments, respectively, the complex remained stable at over 94% for 300 min. Additionally, the complex did not reduce the antioxidant activity of carotene against hydroxyl radicals but slightly lowered its reducing power. Carotene release followed first-order kinetics with an 88.33% recovery over nine days, mainly controlled by diffusion.

Conclusion

Producing apo-13-carotenone-5,6-epoxide as a major product in carotene oxidation by both oxidants suggests that it may serve as a potential biomarker. Other new products were identified that require further study to examine their activities. The prepared chitosan-TPP complex effectively stabilizes carotenes against both ROS while retaining most of their original antioxidant activities, indicating its potential applications in the pharmaceutical and food industries.

Graphical Abstract

Forestry pests pose serious ecological challenges, yet their biological value remains underexplored. This study aimed to convert the destructive longhorn beetle Glenea cantor (G. cantor) into biomass carbon dots (GC-CDs) with both antibacterial and wound healing properties. GC-CDs were synthesized by a simple microwave-assisted method and characterized by techniques such as transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The particles were quasi-spherical with an average size of 1.02 nm and displayed excellent water solubility. In vitro assays confirmed the low cytotoxicity and hemolysis rates of GC-CDs, while in vivo evaluations showed no systemic toxicity. GC-CDs inhibited Escherichia coli growth and enhanced cell migration and wound closure in scratch assays, Transwell tests, and mouse wound models. These results demonstrate that GC-CDs possess dual antibacterial and wound healing activities, offering a sustainable strategy for transforming forestry pests into valuable biomedical resources.

Graphical Abstract

Background

Selenium (Se) deficiency poses significant health risks to human populations globally, necessitating effective biofortification strategies. Amaranth (Amaranthus retroflexus), a nutrient-dense vegetable with demonstrated capacity for Se accumulation in seleniferous soils, represents a promising biofortification vehicle. Critically, arbuscular mycorrhizal fungi (AMF) enhance rhizospheric Se mobilization, yet their synergistic effects on plant energy metabolism remain unexplored.

Results

This pot study investigated the influence of exogenous selenium (Se) treatment on energy metabolism in amaranth colonized by the arbuscular mycorrhizal fungus Glomus mosseae. Using LC–MS/MS-based targeted metabolomics with OPLS-DA and KEGG analysis, we identified 14 differentially expressed metabolites (8 up-/6 down-regulated) in Se-exposed plants. These metabolites mapped to glycolysis, TCA cycle, pentose phosphate pathway, electron transport chain, and amino acid/pyruvate metabolism. Activity assays of key enzymes, including PGI, SDH, G6PDH, 6PGDH, and CCO, revealed potential multi-pathway perturbations in energy metabolism under Se treatment.

Conclusions

Based on these results, it can be concluded that selenium addition significantly affected amaranth energy metabolism.

Graphical Abstract

Background

As a valuable agricultural product derived primarily from cultivated toads, toad venom has been widely used for its significant antitumor properties in pharmacological formulations. However, the structural and biological characteristics of its major constituents, polysaccharides, remain poorly understood, limiting the development of innovative antitumor drugs.

Results

In this study, an extracellular acidic homogeneous polysaccharide (TvPs3-2, average molecular mass: 3.43 × 10² kDa) is isolated from toad venom. Compositional analysis by 1-phenyl-3-methyl-5-pyrazolone (PMP) pre-column derivatization high-performance liquid chromatography (PMP-HPLC) reveals that TvPs3-2 consists of mannose (Man), glucuronic acid (GlcA), glucose (Glc), galactose (Gal), arabinose (Ara), and fucose (Fuc) in a molar ratio of 9.30:26.52:17.26:2.20:8.40:36.31. Comprehensive structural characterization through methylation analysis combined with extensive nuclear magnetic resonance (NMR) spectroscopy indicates a possible backbone: → 4)-β-D-GlcAp-(1 → 3,6)-β-D-Galp-(1 → 3)-α-L-Fucp-(1 → 4)-α-D-Manp-(1 → 2)-β-D-Glcp-(1 → 2,4)-α-D-Glcp-(1 → 4)-β-D-Glcp-(1 → 2)-α-L-Fucp-(1 → 4)-β-D-GlcAp-(1 → , with multiple branched segments. Morphologically, TvPs3-2 exhibits interconnected bulges, undulating surfaces, and square/rhombic crystals while maintaining a triple-helix conformation. Additionally, TvPs3-2 exhibits good antioxidant activity, particularly against 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS, half maximal inhibitory concentration (IC₅₀) = 0.36 mg/mL), alongside moderate 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical scavenging effects. Furthermore, TvPs3-2 demonstrates notable antiproliferative effects on lung (A549), liver (SK-Hep1), and colon (HCT116 and HT-29) cancer cell lines, with the highest efficacy against SK-Hep1 hepatoma cells (IC₅₀ = 1.6 mg/mL), mediated by apoptosis induction, migration inhibition, and modulation of metabolic/oxidative stress pathways, while it demonstrates relatively low inhibitory activity against healthy H9C2(2-1) cells.

Conclusions

This study comprehensively characterizes a novel acidic polysaccharide (TvPs3-2) from toad venom with remarkable antioxidant and antitumor activities, providing a molecular basis for its future application in anticancer drug development.

Graphical Abstract

The red imported fire ant, Solenopsis invicta Buren, 1972, is a significant invasive pest threatening public health, agriculture, and biodiversity. Our previous study revealed that d-(+)-Camphor and 1,8-cineole, the dominant constituents of Artemisia subg. Seriphidium exhibits promising fumigant activity against S. invicta. However, their rapid volatility limits their broader application, requiring innovative formulations for sustained release and environmental compatibility. To address this issue, we developed a slow-release tablet formulation that offers an eco-friendly solution for S. invicta management, reducing environmental impact and promoting sustainability. The tablet ensures controlled release with uniform volatilization, while individual constituents exhibit rapid volatilization. The morphological analysis of the fumigant tablet revealed a rough surface and granulation characteristics that facilitate uniform volatilization. The XRD and TGA analyses confirmed the crystalline structure and thermal stability of the formulation. Stability studies using GC–MS demonstrated minimal degradation over 12 months of storage in an air-tight container, with slight losses of 3.5% d-(+)-Camphor and 2.40% 1,8-cineole. FTIR analysis confirmed the presence of characteristic peaks for both d-(+)-camphor and 1,8-cineole, validating their incorporation in the fumigant tablet. The toxicity evaluation indicated the tablet has significant efficacy against workers and alates, with LC₅₀ values ranging from 0.71 to 17.35 mg/L. The tablet achieved 100% mortality against workers at 0.22 g/L in 120 min, while alates required 0.29 g/L and 300 min in a substrate-free fumigation container. Furthermore, under laboratory-simulated field conditions using single ant mounds, the tablet achieved 100% mortality of all life stages of S. invicta at a concentration of 2.5 g/kg soil after 96 h. Our study highlights the potential of bioactive phytochemicals in sustainable pest management, paving the way for eco-friendly solutions. The findings will significantly contribute to developing a novel fumigant tablet effective against S. invicta, with potential applications extending to various stored grain pests, thereby fostering a more environmentally conscious approach to sustainable pest control.

Graphical abstract

With the widespread application of high-resolution low-altitude remote sensing technology in agricultural monitoring, fine semantic segmentation of crop plots has become a hot research topic. However, due to the high similarity of land features in large-scale agricultural scenes and the presence of complex situations such as blurred land boundaries, achieving accurate semantic segmentation still faces significant challenges. In response to the above issues, this study proposes a hybrid architecture that combines Convolutional Neural Networks and Transformers, aiming to improve the segmentation accuracy of crop plots in complex scenes, especially in handling areas with fuzzy boundaries and similar features. This method innovatively constructs a global local attention mechanism (GPM-Attention), which generates adaptive attention regions through multi-scale convolution operations, significantly enhancing the model's ability to capture global contextual information. This mechanism not only effectively improves the overall segmentation performance, but also significantly reduces computational redundancy and model complexity by optimizing the computation path. In addition, this study constructed a lightweight edge enhancement module (EEI) as an encoder, which not only expands the local receptive field but also enhances the recognition ability of fine-grained features, effectively solving the problem of crop plot edge blurring. To further optimize the feature fusion effect, this study designed a Feature Adaptive Fusion Module (FAM), which efficiently integrates the multi-level features generated by CNN and Transformer encoders, significantly reducing the semantic information loss of small target features. The experimental results demonstrate that the proposed method achieves a significant performance improvement on the publicly available barley remote sensing dataset, attaining a mean Intersection over Union (mIoU) of 80.39%, which represents an 11.33% increase over state-of-the-art approaches. In addition, the method achieves a 14.2% improvement in F1-score, further confirming its effectiveness. Compared to existing techniques, this study presents a more favorable trade-off among segmentation accuracy, computational efficiency, and model complexity, thereby offering reliable technical support for the practical deployment of low-altitude remote sensing imagery in agricultural monitoring applications.

Graphical Abstract