Search Results (4,730)

Low-light (LL) stress is a major abiotic limiting factor in protected cherry tomato production, adversely affecting vegetative growth, inducing oxidative damage, and disrupting fruit sugar metabolism. To clarify the regulatory role of exogenous abscisic acid (ABA) in mitigating LL stress, we examined the effects of varying ABA concentrations on plant growth, antioxidant capacity, and fruit sugar metabolism in cherry tomatoes under low-light conditions. A two-factor randomized complete block design, with two light regimes—normal light (NL, 100% natural sunlight) and low light (LL, 25% natural sunlight)—and three ABA concentrations (CK: 0 mg·L⁻¹, T1: 10 mg·L⁻¹, T2: 20 mg·L⁻¹). Fruits were sampled at three typical ripening stages (green mature, breaker, and red ripe) to evaluate vegetative and reproductive physiological responses. The results showed that exogenous ABA application effectively suppressed LL-induced excessive stem elongation and alleviated LL-caused reductions in stem diameter and biomass accumulation. ABA treatment significantly increased peroxidase (POD) activity and reduced malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) accumulation, thereby relieving LL-triggered oxidative damage. In addition, ABA regulated key sugar-metabolizing enzymes (soluble acid invertase (SAI), sucrose synthase (SS), sucrose phosphate synthase (SPS), and amylase (Amy)) and the transcript levels of related functional genes (HXK1, SPS, SS, AI), thereby mediating stage-dependent fruit sugar metabolism under LL stress. In conclusion, exogenous ABA effectively modulates vegetative growth, antioxidant homeostasis, and stage-specific fruit sugar metabolism, ultimately alleviating low-light stress damage in cherry tomato. Among the tested treatments, 20 mg·L⁻¹ ABA exhibited the most pronounced mitigation effects, which can be recommended as an optimal foliar application concentration for cherry tomato cultivation in low-light protected facilities. Full article

Butyrate, a short-chain fatty acid derived from the gut microbiota, has been linked to depression through correlational studies; however, whether it might act as a sufficient downstream mediator of the antidepressant effects of a probiotic remains poorly understood. To explore this, a chronic unpredictable mild stress (CUMS) rat model was established to evaluate the potential antidepressant effects of Weizmannia coagulans BC99. Behavioral assessments included the sucrose preference test (SPT), forced swim test (FST), tail suspension test (TST), and open field test (OFT). In addition, 16S rRNA sequencing, serum metabolomics, and short-chain fatty acid (SCFA) profiling were performed. Levels of inflammatory cytokines (IL-1β, IL-6, IL-4, and LPS) and brain-derived neurotrophic factor (BDNF) were measured in serum, hippocampus, and colon by ELISA. An independent sodium butyrate supplementation experiment was conducted to test functional sufficiency, and hippocampal BDNF/TrkB/CREB signaling was assessed by Western blotting. Treatment with BC99 was associated with alleviation of CUMS-induced depressive-like behaviors, increased butyrate levels, reduced neuroinflammation (IL-1β, IL-6, LPS, and IL-4), and restored hippocampal BDNF levels. BC99 also enriched butyrate-producing bacterial taxa (e.g., Lactobacillus, Bifidobacterium, Faecalibaculum) and normalized tryptophan and sphingolipid metabolism. Notably, sodium butyrate alone recapitulated several of the behavioral and anti-inflammatory effects observed with BC99 and, as shown by Western blot, partially restored hippocampal BDNF/TrkB/CREB signaling, which was impaired in CUMS rats. Together, these findings suggest that butyrate may be associated with the antidepressant effects of W. coagulans BC99, potentially acting through suppression of neuroinflammation and activation of the BDNF pathway. Our results support further investigation of butyrate-enhancing strategies as a nutritional approach for depression. Full article

Rice chalkiness is a key constraint in breeding high-quality rice, and unbalanced sucrose transport and starch metabolism are its primary causes. To clarify the molecular mechanism by which OsSUT2 regulates rice grain chalkiness formation, the rice cultivar TP309 was used as material, and ossut2 homozygous mutants were generated via CRISPR/Cas9. Systematic studies were performed using genetic complementation, phenotypic identification, cytological observation, transcriptome sequencing, and haplotype analysis. The results show that loss of OsSUT2 function significantly increased grain chalkiness, deteriorated agronomic traits, induced carbon assimilate accumulation in leaves, blocked sugar transport and starch synthesis in grains, and destroyed starch fine structure; the mutant phenotype was largely restored by functional complementation with wild-type OsSUT2. OsSUT2 was expressed in both source and sink organs, with the strongest inhibition detected in the panicles. Mutation of OsSUT2 disrupted sucrose and starch metabolic pathways. Three main haplotypes of OsSUT2 were identified in natural populations, with significant indica–japonica differentiation. OsSUT2 is confirmed as a key regulator of rice chalkiness, providing gene resources and theoretical support for rice quality improvement. Full article

Soybean molasses, a by-product of alcohol-based soy protein concentrate production, is rich in stachyose and other functional oligosaccharides, but its high sucrose content and other fermentable non-target sugars hinder the efficient purification of stachyose. In this study, the sugar-utilization patterns of four commonly used microbial chassis or production strains, Escherichia coli W, E. coli BL21, Saccharomyces pastorianus Weihenstephan 34/70, and Komagataella phaffii (formerly Pichia pastoris) GS115, were systematically compared to identify a suitable host for selective stachyose enrichment. Among them, E. coli W showed the best performance in rapidly consuming non-target sugars while retaining stachyose. Based on this strain, a CRISPR–Cas9 engineering strategy was applied by deleting the endogenous α-galactosidase gene melA and overexpressing the sucrose permease gene cscB. The resulting strain selectively and nearly completely removed sucrose and other non-target sugars from soybean molasses, increasing the proportion of stachyose from <30% to >90% of total soluble solids. Further optimization of nitrogen source level, inoculum size, and initial °Brix improved fermentation performance. These results demonstrate an effective biological pre-purification strategy for selective stachyose enrichment from soybean molasses. Full article

Sugarcane stores sucrose in a living culm for extended periods, yet the respiratory cost of maintaining this storage tissue remains poorly quantified. We quantified growth and maintenance respiration along the culm (internodes 1 to 12) in three genotypes at mid-season (rapid growth) and end-season (maturation) using a composition-based carbon accounting framework derived from measurements of biomass accumulation and composition. Growth respiration was highest in elongating internodes (3 to 6) and declined with maturation, whereas maintenance respiration increased progressively and dominated in mature storage internodes (10 to 12). Consequently, total sink demand remained substantial even after structural growth slowed, indicating that mature internodes continue to require significant metabolic input despite limited biomass production. To evaluate the potential impact of energetic constraints, we simulated reduced mitochondrial energy contribution to assess the sensitivity of respiratory carbon demand to decreased energetic efficiency. These simulations predicted an increase in glucose requirement for respiration across all internodes, with the largest proportional effect in mature tissue where maintenance costs dominated. Despite this predicted increase in respiratory demand, sucrose accumulation was maintained in mature culms, indicating that respiratory carbon loss remains constrained during storage. This suggests that storage tissue operates with relatively high carbon-use efficiency during maintenance-dominated metabolism. We interpret this pattern as consistent with metabolic configurations that reduce ATP demand, potentially involving partial substitution of ATP-dependent reactions by pyrophosphate (PPi)-dependent pathways, although this mechanism was not directly measured. These findings highlight the importance of maintenance respiration and energetic efficiency in determining sink strength and sucrose yield, and they provide a physiological framework for understanding carbon conservation in long-lived storage organs. Full article

Sucrose non-fermenting 1-related kinase (SNRK) is an understudied serine/threonine kinase of the CAMKL family, known for its role in metabolic regulation and cell signaling. Despite its emerging relevance in various biological processes and diseases, the phosphoregulatory landscape of human SNRK (valid substrates or role of its phosphosites) remains unexplored and demands robust, large-scale, data-oriented approaches to predict the potential substrates. A comprehensive analysis of global human phosphoproteomics datasets was performed to systematically identify class I phosphosites on SNRK, along with their predicted upstream kinases, potential downstream substrates, and coregulated phosphoproteins. Our analysis resulted in the identification of 33 dark SNRK phosphosites, of which 19 were differentially regulated across an array of experimental conditions. Among them, S518 and S569, outside their kinase domain, were the most frequently regulated and co-occurred phosphosites under diverse conditions. Notably, S569 is predicted as a candidate autophosphorylation site of SNRK. In these contexts, coregulation analysis of proteins and their phosphorylation sites suggested associations of phospho-SNRK in cell cycle progression, chromatin organization, and DNA replication. Uncovering candidate upstream kinases and potential substrates for prioritized validation, this study provides the first comprehensive phosphoproteomic map of SNRK, serving as a foundation for future investigations into its signaling network associations and therapeutic approaches. Full article

Sugars play a pivotal regulatory role in floral bud dormancy release in Prunus mume, a process that critically determines subsequent flowering time. However, the precise molecular mechanisms linking sugar metabolism to this developmental transition remain poorly understood. To address this gap, we integrated physiological profiling and transcriptomic sequencing using two cultivars with contrasting flowering phenologies: the early-flowering ‘Chaotang Gongfen’ (CTGF) and the late-flowering ‘Shichu Jin’ (SCJ). Exogenous sugar treatments were applied separately to floral buds of the cultivar ‘Yilian’ to evaluate the effect of sugars on dormancy release. During dormancy release, glucose and sucrose contents increased progressively and showed significant positive correlations with bud break rates in both CTGF and SCJ (r > 0.75). Consistently, exogenous application of glucose and sucrose significantly accelerated bud break in ‘Yilian’, whereas mannose exhibited an inhibitory effect. Transcriptome analysis of CTGF and SCJ revealed significant enrichment of starch and sucrose metabolism, hormone signal transduction, and stress-responsive pathways. Key metabolic genes, notably the α-amylase gene PmAMY1-2 and the cell wall invertase genes PmCWINV1/4, were upregulated during this transition. Weighted gene co-expression network analysis (WGCNA) further identified PmFRK4, PmSUS6, and the aforementioned invertases as candidate genes within a sugar-associated regulatory module. Collectively, these findings support a model in which glucose and sucrose accumulation promotes endodormancy release via the transcriptional activation of starch and sucrose catabolic pathways. This study provides a theoretical framework for deciphering dormancy regulation in woody perennials and offers potential targets for the precise manipulation of flowering time. Full article

In this study, multiple samples were collected from different urea-fertilized agricultural lands, and their fungal strains were isolated using the tenfold serial dilution method on potato dextrose agar plates. In total, 21 strains were identified as urease-positive through primary screening on Christensen medium. Secondary screening of selected fungal isolates conducted through submerged fermentation could then identify the fungal strain 10⁻⁵ S₁₁ brown as the most effective urease producer that exhibited maximum urease activity (682 U/mL/min). It was identified by scotch tape microscopy for morphological characterization and subsequently confirmed through 18S rRNA sequencing as Aspergillus terreus. Further, optimization of fermentation conditions showed that M9 medium containing 1.5% urea as a nitrogen source at pH 5.5, in addition to 3% sucrose as a carbon source, 4% inoculum size, and 7 days of incubation at 30 °C, produced the best fermentation and enhanced the urease activity from 682 U/mL/min to 1050 U/mL/min. Subsequently, the optimized urease enzyme was mixed with clean sand to induce carbonate precipitation to enhance its unconfined compressive strength from 22.5 kPa for untreated samples to 154.2 kPa for treated samples after 28 days, with subtle permeability reduction from 4.26 × 10⁻³ cm/s to 1.7 × 10⁻³ cm/s. Full article

Background: Optimized nitrogen (N) application and planting density can enhance sweet potato yield. However, the agronomic mechanisms underlying their effects on photosynthetic efficiency and carbohydrate metabolism in sweet potato remain unclear. Methods: To address this, a two-year field experiment was conducted using a split-plot design with two varieties (YS-25 and GX-14), three N levels (60, 90, and 120 kg/ha; designated N60, N90, and N120, respectively), and three planting densities (D1–D3: 50,000, 62,500, and 83,333 plants/ha). Each treatment was replicated three times. Results: The results showed that the N60D2 treatment (60 kg/ha N; 62,500 plants/ha) optimized canopy light distribution by significantly increasing IPAR, light transmission rate, and extinction coefficient (K). This treatment enhanced individual plant photosynthetic capacity (higher photosynthetic rate: Pn, Ci, Gs, and Tr) and light energy use efficiency (Fv/Fm, Y(II), ETR, and qP), and promoted carbohydrate metabolism (sucrose, starch, fructose, and glucose) by increasing enzyme activities (Rubisco, SuSy, SPS, NI, SSS, and AGPase) in functional leaves and roots. These effects improved source–sink coordination, ultimately increasing storage root yield by 63.27–95.47% compared with the control plants (N120D1). Correlation analysis revealed that single-plant root weight and medium-sized root count were important yield determinants for both varieties. Conclusions: These results indicate that reducing nitrogen fertilizer combined with dense planting shapes a reasonable canopy structure for light distribution at the population level and optimizes light and carbon use efficiency at the individual plant level, thereby improving storage root yield and commercial characteristics of sweet potato. Full article

To understand the mechanism of sweetness formation in vegetable soybean seeds, an integrative transcriptomic and metabolomic analysis was conducted using high sweetness (HS) and low sweetness (LS) varieties selected from 287 resources based on electronic tongue evaluation. The HS variety exhibited significantly higher levels of soluble sugars (58.91 mg/g) and free amino acids (54.15 mg/g). Transcriptomic results indicated that DEGs correlated with glycolysis/gluconeogenesis, starch and sucrose metabolism, and biosynthesis of amino acids pathways were significantly up-regulated in the HS variety. Metabolomic analysis showed that DAMs were significantly enriched in the biosynthesis of secondary metabolites, the amino acid biosynthesis, and the pentose phosphate pathway. Co-expression network analysis further demonstrated correlations between DEGs and DAMs related to glycolysis/gluconeogenesis and amino acid biosynthesis. Eight candidate genes related to sweetness formation were identified through transcriptomic data and validated by RT-qPCR. The present findings represent a fundamental advance in understanding the regulatory mechanisms underlying the sweetness of vegetable soybeans. Full article

This study aimed to evaluate the leaching of nutrients and pathogens following the surface application of pH-modified slurry on sandy soil. Three slurry pH modification strategies—mineral and biological acidification (pH 5) and alkalinization (pH 9.5)—were tested using mineral acids or bases, paper-industry by-products, or combinations of additives. We hypothesized that: (i) acidification increases nitrogen (N) and phosphorus (P) leaching through nutrient solubilization, and (ii) effective sanitization reduces the risk of pathogen leaching. A 24-day column leaching experiment was conducted with slurry applied at 240 kg N ha⁻¹ and four weekly irrigation events. Results indicated that nitrate (NO₃⁻) leaching accounted for less than 15% of the total nitrogen applied; however, acidified slurry significantly increased ammonium (NH₄⁺) leaching by 72%. The combination of H₂SO₄ with sucrose reduced NH₄⁺ and NO₃⁻ leaching, although P leaching exceeded 35% of the total P applied. Sulphur (S) concentrations in leachates ranged from 42.3 to 112.8 mg S kg⁻¹ soil, particularly in treatments involving H₂SO₄ or SO₄²⁻—rich additives such as spent acid. Faecal coliform leaching declined throughout the study, with acidified slurry consistently maintaining levels below the threshold for irrigation water (<100 MPN/100 mL). Regarding nutrient leaching, pH-modified slurry may present a higher risk of N, P and S leaching compared to untreated slurry, which could also be interpreted as an increase in plant nutrient availability. Full article

Honey adulteration remains a major challenge for ensuring food authenticity and sustainable quality control. In this study, near-infrared (NIR) spectroscopy and hyperspectral imaging (HSI) were comparatively evaluated as green, non-destructive analytical techniques for the discrimination of pure and adulterated honey using chemometric modeling. A total of 180 honey samples, including pure and adulterated samples with agave syrup, sucrose syrup, or water at varying concentrations, were analyzed using two NIR platforms (MicroNIR™ 1700 and NIRS™ DS2500) and an HSI system (Micro-Hyperspec^® NIR camera). Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were applied for exploratory analysis and supervised classification, respectively. Both techniques enabled effective discrimination between pure and adulterated honey. The results demonstrated that the two NIR platforms achieved superior classification performance: the MicroNIR™ 1700 yielded overall sensitivities, specificities, and accuracies of 100%, respectively. While the HSI system provided complementary spectral-spatial information, its performance and that of the NIRS™ DS2500 were slightly lower, with an overall accuracy of 93.10%, particularly at low levels of adulteration (≤10%). Overall, these results demonstrate that NIR-based spectroscopy is a reliable, fast, non-destructive, and eco-friendly analytical tool for testing the authenticity of honey. The portable NIR system, in particular, provides a cost-effective and field-deployable solution for in situ quality control. Integrating it into routine quality control practices could help prevent food fraud, protect consumer trust, and promote sustainable industry development. Full article

Lilium longiflorum is a diploid lily species valued for its tolerance to humid–hot environments and pleasant fragrance. However, its poor cold hardiness and low bulb-forming capacity limit its cultivation. To overcome these deficiencies, autotetraploids were previously generated in our laboratory via somatic doubling. In order to expand the reproductive efficiency of the two, this study optimized in vitro regeneration and bulblet enlargement protocols. We analyzed the effects of various plant growth regulators and sucrose concentrations, alongside the expression of genes related to carbohydrate metabolism and hormone signaling. Results revealed divergent regenerative pathways: diploids favored direct organogenesis (optimal medium: MS + 30 g/L sucrose + 0.5 mg/L 6-BA + 0.2 mg/L NAA + 1.0 mg/L glyphosate), whereas tetraploids thrived via a TDZ-induced callus pathway (1/2 MS + 30 g/L sucrose + 1.0 mg/L NAA + 0.2 mg/L TDZ). During bulblet enlargement, diploids were predominantly regulated by IBA and prone to proliferation (optimal enlargement medium: MS + 60 g/L sucrose + 2.0 mg/L IBA), while tetraploids were sucrose-sensitive and prioritized single-bulb hypertrophy (MS + 60 g/L sucrose + 0.5 mg/L IBA + 0.1 mg/L 6-BA + 0.1 mg/L CPPU). qRT-PCR indicated that LlAGPS1, LlGBSSI, LlSWEET15, LlMYC2, and LlSAUR32 were highly expressed in tetraploids during rapid enlargement (24–36 d), suggesting a role in bulb hypertrophy, whereas upregulated LlSUS4 and LlCWIN3 in diploids correlated with proliferation. The study provides a practical technical reference for the industrialized propagation of high-quality L.longiflorum bulbs and provide a theoretical foundation for understanding ploidy-dependent development in Lilium. Full article

Rapeseed straw and peanut vine are abundant agricultural by-products in China, but their low digestibility has largely restricted their application in ruminant production. Extrusion processing has been shown to improve the fiber structure and nutrient availability of roughages, yet the underlying metabolic mechanisms by which extruded rapeseed straw (ERS) influences growth performance remain insufficiently elucidated. This study aimed to explore the metabolic mechanisms of average daily gain (ADG) affected by rapeseed straw feeding through studying metabolites from four biological matrices (rumen fluid, serum, liver and muscle) collected from 24 Hu lambs fed extruded rapeseed straw (ERS, n = 12) and peanut vine hay (PVH, n = 12). The Hu lambs fed ERS exhibited greater ADG during the late finishing stage (60–90 d) than those fed PVH (p = 0.03). A total of 666, 274, 147, and 96 metabolites were identified in the rumen fluid, liver, serum and muscle, respectively. In addition, nine, 12, seven, and three significantly different metabolites (VIP > 1 and p < 0.05) related to eight significant pathways (starch and sucrose metabolism, galactose metabolism, glyoxylate and dicarboxylate metabolism, glycerophospholipid metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, Gly, Ser, and Thr metabolism, arginine biosynthesis, and purine metabolism) were identified in the four biological matrices between the ERS- and PVH-fed Hu lambs. Further integrated key metabolic pathway analysis showed that the ERS-fed Hu lambs may have more comprehensive amino acid and energy metabolisms with relatively fewer carbohydrate metabolisms, suggesting enhancing protein deposition and energy utilization efficiency with associated metabolites and pathways serve as key biomarkers for a higher ADG of Hu lambs when fed ERS. Full article

Elevated temperatures due to global climate change adversely affect plant growth and development, which has become a major factor restricting wheat (Triticum aestivum L.) production. Despite the introduction of dwarfing genes that have enhanced lodging resistance as well as productive potential in wheat breeding, lodging still affects wheat yields. Plant growth regulators are widely recognized as effective agents in mitigating crop lodging. Few studies have investigated the high-temperature lodging sensitivity of wheat genotypes from different breeding periods, nor have they examined how uniconazole-sucrose regulates lodging resistance under heat stress. To fill this research gap, an experiment was conducted in which two contrasting wheat genotypes from different periods, Bima 1 (BM1, ~135 cm tall, a historical genotype released in 1953, lodging-susceptible) and Shannong 28 (S28, ~75 cm tall, a modern genotype released in 2014, lodging-resistant), were exposed to high temperature stress combined with uniconazole-sucrose application. The results showed that high-temperature-induced increases in plant gravity center height, together with decreased stem diameter coefficient, stem plumpness, and lignin deposition, were the main factors responsible for the reduction in bending section factor and mechanical strength of wheat stems. These modifications are associated with reduced lodging resistance, increased susceptibility to lodging, and significant yield losses. Nevertheless, exogenous application of uniconazole-sucrose lowers plant gravity center height, enhances stem diameter coefficient, stem plumpness, and lignin content, thus alleviating lodging risk and boosting wheat yield under high temperature stress. High temperature stress was associated with downregulated relative expression levels of key genes involved in lignin metabolism and reduced activities of the corresponding key enzymes, as well as inhibited lignin biosynthesis and accumulation in stems and increased incidence of wheat lodging. Conversely, foliar spraying of uniconazole-sucrose alleviated these suppressive effects on lignin biosynthesis, thus enhancing stem mechanical strength and reducing the lodging index of wheat. Moreover, these indicators were more sensitive to heat stress or uniconazole-sucrose treatment in BM1. The two genotypes examined suggested a potential trend that S28 may exhibit reduced sensitivity to high temperature in terms of mechanical traits and lignin synthesis, which could contribute to enhanced lodging resistance under heat stress. Full article