Search Results (1,746)

Background: Flavonoid secondary metabolites accumulate in xylem during heartwood formation and critically influence wood color and economic value. However, the distribution patterns of individual flavonoids across sapwood, transition zone, and heartwood remain poorly characterized in Castanopsis hystrix, limiting mechanistic understanding of heartwood formation and rational resource utilization. Methods: Sapwood, transition zone, and heartwood samples were collected and analyzed using ultra-performance liquid chromatography coupled with Q-Exactive Orbitrap mass spectrometry (UPLC-QE-MS) for qualitative and quantitative flavonoid determination. Multivariate statistical approaches, including hierarchical clustering, principal component analysis (PCA), and orthogonal partial least-squares discriminant analysis (OPLS-DA), were applied to compare regional metabolic profiles and to identify characteristic differential markers. Results: A total of 26 flavonoids were identified, covering flavones, flavonols, flavanones, dihydroflavonols, and flavanols. Quantitative and cluster analyses revealed distinct region-preferential accumulation: dihydrorobinetin, dihydromyricetin, morin, and kaempferol were highly enriched in heartwood; fustin, taxifolin, and cyanidin predominated in the transition zone, whereas afzelin and astilbin were more abundant in sapwood. PCA and OPLS-DA further selected four characteristic markers, namely dihydromyricetin, dihydrorobinetin, kaempferol and (−)-epicatechin, that effectively discriminated the three regions. Conclusions: This study establishes a clear radial gradient of flavonoid accumulation in C. hystrix xylem, demonstrating selective enrichment of specific metabolites from sapwood to heartwood. These findings provide essential data for deciphering the biochemical mechanisms of heartwood formation and offer a metabolic basis for quality assessment and high-value utilization of this timber species. Full article

The aerial parts of Nanhaia speciosa are often discarded despite their potential as a source of bioactive compounds. This study aimed to characterise this underutilised biomass and evaluate its functional properties relevant to carbohydrate digestion. Ultra-high-performance liquid chromatography–quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS), Global Natural Products Social (GNPS) molecular networking, and MS/MS fragmentation analysis tentatively annotated 96 compounds, mainly flavonoids and nitrogen-containing constituents. The extract inhibited α-glucosidase and α-amylase in a concentration-dependent manner, with IC₅₀ values of 9.98 ± 0.02 and 174.83 ± 1.31 μg/mL, respectively, compared with 29.73 ± 0.04 and 39.46 ± 0.19 μg/mL for acarbose. The extract also showed measurable chemical antioxidant capacity. Network pharmacology suggested potential involvement of cAMP-, calcium-, and receptor-associated signalling. Molecular docking prioritised butein as a candidate constituent with favourable predicted interactions with both enzymes, and molecular dynamics simulations supported stable predicted binding. The estimated MM/GBSA binding free energies of butein were −36.68 and −32.03 kcal/mol for α-glucosidase and α-amylase, respectively. These findings indicate that the aerial biomass of N. speciosa is a promising source of phytochemicals with potential carbohydrate-hydrolase inhibitory properties, although the activity of individual constituents requires further experimental validation. Full article

The growing accumulation of microplastics in marine ecosystems, coupled with the presence of emerging contaminants such as pharmaceuticals, represents an environmental problem that has received little attention to date. The present study evaluates the potential of microplastics to act as transport vectors for pharmaceuticals through their adsorption onto two plastic polymers widely used today: polyethylene terephthalate (PET) and medium-density polyethylene (MDPE) in seawater. As a control, the same experiments were conducted in ultrapure water (Milli-Q). Both plastics were exposed to a mixture of 29 pharmaceuticals belonging to different therapeutic classes over a 28-day period, with sampling conducted at various time intervals. The identification, quantification, and characterization of the compounds were performed using ultra-high-performance liquid chromatography coupled with mass spectrometry detection. Statistical analysis was performed using R-Studio software. Outcomes reveal that the type of polymer significantly influences adsorption, with MDPE being more efficient than PET. In contrast, the type of water and the therapeutic class of the drugs were not identified as determining factors. Furthermore, a positive, albeit moderate, correlation was observed between the hydrophobicity of the pharmaceutical and its adsorption efficiency on MDPE. These findings suggest that hydrophobic interactions play a key role in the adsorption of drugs onto microplastics, providing a solid foundation for future research, such as predictive models or mitigation strategies in aquatic ecosystems. Full article

Objective: This study established a rat model of lipopolysaccharide (LPS)-induced acute lung injury (ALI) to evaluate pathological damage, collagen deposition, inflammatory cytokine levels, and key gene/protein expression following Hedyotis diffusa water extract (HDWE) intervention. Combined with ultra-high-performance liquid chromatography-quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS), transcriptomic analysis, and molecular simulation, this study identified the bioactive components of HDWE, evaluated their potential interactions with ALI-related targets, and explored the multi-omics-based protective mechanisms of HDWE. Methods: Thirty-six Sprague–Dawley (SD) rats were randomly divided into six groups: Control group, ALI group, DXMS group, HDWE-L group (100 mg/kg), HDWE-M group (200 mg/kg), and HDWE-H group (300 mg/kg). Hematoxylin and eosin (H&E) and Masson’s trichrome staining were used to evaluate lung pathological changes and collagen deposition. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum tumor necrosis factor-α $\mathrm{T}\mathrm{N}\mathrm{F}-\mathsf{\alpha }$ interleukin-1β $\mathrm{I}\mathrm{L}-1\mathsf{\beta }$, erleukin-6 (IL-6), and interleukin-10 (IL-10) levels. Transcriptomic analysis identified differentially expressed genes (DEGs), followed by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), receiver operating characteristic (ROC), and immune infiltration analyses. Quantitative real-time polymerase chain reaction (qRT-PCR) detected the mRNA expression levels of SPHK1, RELA, and NFKBIA. Immunohistochemistry evaluated the expression of eight hub targets, including endothelin-1 (EDN1), sphingosine kinase 1 (SPHK1), intercellular adhesion molecule 1 (ICAM1), interleukin-17 (IL-17), prostaglandin-endoperoxide synthase 2 (PTGS2/COX-2), NF-κB p65 (encoded by RELA), WT1-associated protein (WTAP), and myeloperoxidase (MPO). UHPLC-Q-Orbitrap HRMS characterized HDWE constituents. Molecular docking analysis was performed between 22 compounds and eight hub targets, followed by 100 ns molecular dynamics simulations and molecular mechanics-Poisson–Boltzmann surface area (MM/PBSA) binding free energy calculations for five core targets. Compared with the control group, the ALI group showed increased levels of TNF-α (86%), IL-1β (107%), and IL-6 (66%), accompanied by a 43% reduction in IL-10 and a 300% increase in lung collagen deposition. All HDWE doses alleviated inflammatory responses, with medium-dose HDWE showing the most pronounced effects. Specifically, medium-dose HDWE increased IL-10 levels by 52% and reduced IL-6, TNF-α, and IL-1β levels by 18%, 22%, and 11%, respectively. Transcriptomic analysis identified 2512 DEGs between the control group and ALI groups, 832 exclusive DEGs between the ALI group and HDWE-M groups, and 876 overlapping DEGs enriched in TNF, IL-17, and NF-κB signaling pathways. The eight-hub-gene diagnostic model achieved an area under the curve (AUC) of 0.969. RELA, SPHK1, and four other hub genes showed positive correlations with Th1, Th17, and neutrophil infiltration. In the ALI group, SPHK1, RELA, and NFKBIA mRNA expression levels were 1.30-, 0.96-, and 0.71-fold of those in the control group, respectively. Compared with the ALI group, high-dose HDWE treatment and low-dose HDWE treatment reduced SPHK1 expression to 0.62- and 0.57-fold, respectively, and increased NFKBIA expression to 1.68- and 1.58-fold, respectively. High-dose HDWE treatment reduced RELA expression to 0.43-fold. The expression levels of inflammation-related proteins were increased in the ALI group and were reduced after HDWE treatment. Twenty-two HDWE components were identified, 16 of which met the docking criteria. Asperulosidic acid exhibited favorable predicted binding affinities with all eight targets, with calculated binding free energies of −14.74, −14.92, −17.58, −23.04, and −16.10 kcal/mol for MPO, IL-17, NF-κB p65, PTGS2/COX-2, and SPHK1, respectively. Conclusions: This study provides systematic in vivo pharmacodynamic and in silico component-target evidence regarding the protective effects of HDWE against LPS-induced ALI. HDWE treatment increased NFKBIA expression and reduced SPHK1, RELA, and multiple inflammatory protein levels, suggesting that HDWE may regulate the IL-17/NF-κB-associated inflammatory network, although direct causal relationships require further validation. Asperulosidic acid may represent a key bioactive component with broad target-binding potential. This study was limited by the use of an LPS-induced rat ALI model without gene knockout or target inhibitor validation; therefore, further functional experiments are required to confirm the proposed regulatory mechanisms. Full article

Evodia rutaecarpa is a valuable medicinal plant, yet its non-medicinal tissues remain largely underexplored. Here, we integrated ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)-based widely targeted metabolomics and RNA sequencing (RNA-seq) transcriptomics to systematically profile the metabolic and transcriptional landscapes of roots, stems, leaves, and flowers of Evodia rutaecarpa (Juss.) Benth. Our aim was to characterize tissue-specific metabolic differentiation and its underlying transcriptional regulatory mechanisms. Metabolomic analysis, employing principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) with robust model parameters (R²Y > 0.9, Q² > 0.5), identified 3090 differential metabolite features (variable importance in projection, VIP > 1.0; p < 0.05) across the four tissues, which exhibited distinct tissue-specific clustering patterns. Integrated Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and weighted gene co-expression network analysis (WGCNA) revealed that roots specifically accumulated quinolone alkaloids and flavonoid glycosides, accompanied by the coordinated upregulation of genes involved in flavonoid and phenylpropanoid biosynthetic pathways. In contrast, stems, leaves, and flowers were enriched in indole alkaloids (evodiamine and rutaecarpine) and volatile oil precursors, with concurrent upregulation of genes involved in tryptophan metabolism and indole alkaloid biosynthesis (e.g., tryptophan decarboxylase, TDC; s N-methyltransferase, NMT). Notably, leaves and flowers displayed particularly high accumulation levels of these bioactive alkaloids, suggesting their potential as alternative sources for industrial and pharmaceutical applications. WGCNA further identified multiple transcription factors and structural gene modules tightly correlated with evodiamine accumulation, offering promising candidate regulators for future biosynthetic pathway engineering. Collectively, this multi-omics integration study systematically elucidates the tissue-partitioned secondary metabolism of Evodia rutaecarpa (Juss.) Benth. and provides a solid scientific foundation for full-plant resource utilization, targeted development of non-medicinal tissues, and future metabolic engineering of indole alkaloid production. Full article

Flonicamid is a systemic pyridinecarboxamide insecticide used to control sap-sucking pests in agricultural crops. An ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method was developed for the simultaneous determination of flonicamid and its metabolites, N-(4-trifluoromethylnicotinoyl)glycine (TFNG), 4-(trifluoromethyl)nicotinamide (TFNA-AM), and 4-(trifluoromethyl)nicotinic acid (TFNA) in rice plants, brown rice, rice husks, paddy soil, and paddy water. Method validation showed average recoveries of 73–115% with relative standard deviations of 1.1–9.9% across different matrices at three fortification levels. Field and laboratory experiments were conducted to characterize the dissipation, degradation, and transformation of flonicamid in the paddy ecosystem, and the dietary risk was assessed. Field dissipation followed first-order kinetics, with half-lives of 5.8, 2.9, and 7.1 days in rice plants, paddy soil, and paddy water, respectively. Under laboratory conditions, degradation proceeded markedly faster under aerobic than anaerobic conditions, with half-lives of 0.8–7.1 and 4.7–17.8 days in five typical Chinese soils, respectively. Six transformation products were identified by UHPLC–Q-TOF/MS coupled with UNIFI software (v1.9.4.0), including a novel product (M210) reported for the first time. At pre-harvest intervals of 7–21 days, terminal residues of flonicamid in brown rice were all below the Chinese maximum residue limit (MRL) of 0.1 mg/kg. Dietary risk assessment revealed that the acceptable daily intake percentages (%ADI) for 12 population subgroups ranged from 0.128% to 1.031% based on the parent compound, and from 0.404% to 3.808% under the EU residue definition. All values were far below 100%. These results indicate that flonicamid, when applied according to Good Agricultural Practice (GAP), poses a negligible dietary risk to consumers. Full article

Background: γ-Valerolactone (GVL), a green volatile platform compound derived from lignocellulosic biomass, has recently been identified as one volatile organic compound produced by the plant growth-promoting rhizobacterium Stutzerimonas stutzeri NRCB010. Although our previous transcriptomic and phenotypic studies have verified that exogenous GVL can promote the growth of tomato seedlings, the global metabolic reprogramming behind this promoting effect remains unclear. Methods: Tomato seedlings were subjected to exogenous GVL treatments at three concentrations (0, 0.25, 0.5 g/L) for 24 h and 48 h separately. Combined with physiological growth measurements, ultra-high-performance liquid chromatography–tandem mass spectrometry-based widely targeted metabolomics was applied to systematically characterize GVL-mediated metabolic reprogramming. Results: GVL remarkably improved seedling height, biomass and root development, with 0.25 g/L GVL showing the strongest promoting effect. A total of 703 metabolites including lipids, flavonoids and alkaloids were identified. Principal component analysis and orthogonal partial least squares discriminant analysis revealed distinct metabolic separation between control and treated groups, verifying time and concentration dependent metabolic shifts. After 24 h, GVL activated primary pathways (the tricarboxylic acid cycle, amino acid and purine metabolism) to supply growth energy; after 48 h, central carbon and secondary biosynthetic pathways were enriched, and 0.5 g/L GVL specifically triggered defensive isoquinoline and indole alkaloid biosynthesis. Conclusions: GVL coordinately remodels primary and secondary metabolic networks to accelerate tomato seedling growth, which provides sufficient metabolomic evidence for developing GVL as a novel bio-based plant biostimulant. Full article

Background/Objectives: The whole plant of Tetrastigma hemsleyanum is used medicinally, but the tuberous root is by far the most commonly used part, and the way in which its metabolites are partitioned among organs and among geographic origins underpins both the rational choice of the medicinal part and the evaluation of herb quality. Methods: Here, untargeted metabolomics based on ultra-high-performance liquid chromatography coupled to high-resolution Orbitrap mass spectrometry was used to compare roots, stems and leaves collected from nine regions of southern China (81 samples) with tuberous roots collected from 17 sites in seven provinces (51 samples). Annotations were graded according to the Metabolomics Standards Initiative (MSI), curated with explicit plausibility rules, and every conclusion was re-tested across five nested annotation subsets. Results: Organ identity was the dominant source of metabolic variation: the three organs were completely separable (random forest out-of-bag accuracy 100%), the organ effect was about four times larger than that of sampling region (PERMANOVA pseudo-F 16.7 versus 4.1), and this contrast was essentially unchanged from the complete set of 615 annotations down to the most stringent subset of 19 flavonoids and phenolic acids. The organ-level pattern was chemically coherent: amino acids and lipids were relatively enriched in the tuberous root, soluble sugars and phenolic acids in the stem, and flavonoids and alkaloids in the leaf, matching the contrasting roles of a storage, a transport and a photosynthetic organ. Geographic differences among tuberous roots were, by contrast, weak and largely local: although provinces could be separated with 88.9% out-of-bag accuracy, accuracy fell to 42.2% when an entire, previously unseen collection site was held out (chance level 20%), and to 52.9% for a coarse macro-geographic zone (chance level 25%), whereas holding out an entire sampling region left organ classification unaffected (100%). Conclusions: The present data therefore document a strong, generalisable and chemically interpretable organ division of labour, but do not support the use of this metabolome for origin authentication. Because most annotations remain at MSI Level 3, individual compounds are reported as putative throughout, and all conclusions rest on multivariate and class-level evidence. Full article

Organophosphate esters (OPEs) are commonly used flame retardants and plasticizers, which can easily be released into the soil environment and have potential hazards such as neurotoxicity and developmental toxicity. Establishing an efficient and sensitive detection method plays a crucial role in soil pollution assessment. Currently, there have been numerous studies on the detection of OPEs in soil using ultrasonic extraction and solid-phase extraction, while relatively few studies have focused on the analysis of multiple OPEs in soil by accelerated solvent extraction combined with d-SPE clean-up and ultra-high performance liquid chromatography–tandem mass spectrometry. The d-SPE purification method eliminates the need for column passage, shortens sample preparation time, and avoids the risk of background contamination from OPEs that may be introduced by SPE. This study developed a liquid chromatography–tandem quadrupole mass spectrometry (LC-MS/MS) method for the determination of 25 OPEs in soil, and systematically optimized the pretreatment and instrumental analysis conditions. Accelerated solvent extraction was used for pretreatment, and dichloromethane–methanol (1:1, V/V) was determined as the optimal extraction solvent. A mixed adsorbent of N-propyl ethylenediamine (PSA) and C18 was selected for dispersive purification, effectively removing matrix interference and improving recovery rates. The mass spectrometry parameters such as collision energy and declustering voltage were optimized, significantly enhancing ion response intensity and detection sensitivity. The method showed good linearity within the concentration range of 1–100 ng/mL, with correlation coefficients all greater than 0.994. The spiked recovery rates ranged from 70.6% to 111% with a relative standard deviation (RSD) of 1.2–11.8%. The precision and accuracy met the requirements for environmental sample analysis. The method was applied to the detection of actual soil samples, and the results were stable and reliable. This method is simple to operate, highly sensitive, and widely applicable, providing reliable technical support for the pollution monitoring, source tracing, and ecological risk assessment of OPEs in soil. Full article

Xueshan Jinluohan Pain-Relief Liniment (XJPL) is a Tibetan topical compound preparation composed of 11 medicinal materials. Its current quality standard relies mainly on thin-layer chromatographic identification, which is insufficient to comprehensively characterize its complex chemical composition, marker constituents from key medicinal materials, and batch-to-batch quality consistency. In this study, 17 batches of XJPL were analyzed by ultra-performance liquid chromatography coupled with quadrupole-Exactive Orbitrap high-resolution mass spectrometry (UPLC-Q-Exactive Orbitrap MS) for systematic chemical profiling. An integrated quality evaluation method was further developed by combining high-performance liquid chromatography (HPLC) fingerprinting, similarity evaluation, chemometric analysis, and multicomponent quantification. A total of 139 chemical constituents were confirmed by reference standards or putatively characterized, including alkaloids, flavonoids, phenolics, terpenoids, organic acids, lactones, and other compounds, indicating the coexistence of multiple medicinal-material-derived and structurally diverse constituents in XJPL. The HPLC fingerprint established for the 17 batches contained 23 common peaks, among which 10 representative constituents were assigned, and similarity evaluation indicated a high degree of overall chemical consistency among batches. Hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least squares-discriminant analysis (OPLS-DA) further revealed batch-related differences and suggested that common peaks corresponding to gentiopicroside, loganic acid, and related constituents contributed substantially to sample differentiation. On this basis, quantitative methods were established for representative constituents covering phenolic acids, iridoid glycosides, carotenoid glycosides, and Corydalis-derived alkaloids. Overall, this study improves the quality evaluation framework for XJPL by integrating chemical profiling, holistic fingerprint assessment, batch-difference characterization, and multicomponent quantitative control, providing experimental support for quality standard improvement and manufacturing quality control. Full article

Background/Objectives: Traditional medicinal plants play a crucial role in infants’ healthcare in underdeveloped countries and communities where access to modern medicine is limited. In Limpopo, the Vhavenda tribe has a custom of feeding babies as young as a day old with tshiunza, a very light and warm, soft porridge prepared in medicinal plant extracts, believed to help treat various ailments and boost the immune and digestive systems. However, reports of negative side effects, including vomiting, haematuria, renal inflammation and hospitalisations, highlight safety concerns of these traditional practices. This study aimed to profile the chemical composition of soft porridge samples prepared in aqueous extracts of medicinal plants reported to be commonly used in infants’ food in the Venda region of Limpopo; Annona senegalensis (roots), Piliostigma thonningii (leaves), Carissa edulis (roots) and Bauhinia galpinii (leaves). Methods: Ultrahigh-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-qTOF-MS) was used for metabolic profiling, followed by putative compound identification using feature-based molecular networking and a compound fragmentation predictor tool, SIRIUS. To evaluate the toxicity of these plants, a cytotoxicity assay was conducted using plant extracts on African monkey kidney cells. Results: Different classes of polyphenols, including flavonoids (flavan-3-ols and flavonols) and hydroxycinnamoyl amides, were among the dominant compounds putatively identified in the methanolic extracts of soft porridge prepared from the four plant extracts. A. senegalensis aqueous extracts were inactive (IC₅₀ > 500 µg/mL, 55.57% viability at 500 µg/mL), while P. thonningii was non-cytotoxic (105–132% viability within the tested concentration range). Conclusions: Although no toxic compounds were identified and no cytotoxic potential was observed in the tested plant extracts, this does not translate to the safe use of medicinal plants in infants’ food. Therefore, future studies should conduct pharmacological and toxicological evaluations to better understand the potential risks of these plant extracts to infant health. Full article

The determination of pesticide residues in citrus fruits remains analytically challenging due to their high acidity and complex chemical compositions, which can compromise extraction efficiency and promote significant matrix effects, particularly for acidic compounds. In this study, an acidified acetonitrile-based QuEChERS method was developed and validated for the multiresidue determination of 136 pesticides in Tahiti lime (Citrus latifolia) using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS/MS). The proposed approach employs 1% formic acid in acetonitrile and omits the conventional clean-up step, aiming to improve analyte recovery and analytical throughput. Method validation was performed according to SANTE guidelines, demonstrating satisfactory linearity (R² ≥ 0.99 for all analytes), limits of quantification of 0.01 mg kg⁻¹, and recoveries within 70–120%, with relative standard deviations ≤ 20% for the vast majority of compounds. Notably, the method achieved consistent and reliable performance for 12 acidic pesticides, which are typically problematic in conventional QuEChERS approaches. Application to 22 real samples revealed the presence of 14 pesticide residues, with some compounds exceeding European Union (EU) maximum residue limits. The proposed method provides a simple, efficient, and robust alternative for comprehensive pesticide monitoring in citrus fruits, with particular advantages for the determination of acidic compounds in highly complex matrices. Full article

Background: Plasmid-mediated colistin resistance threatens the effectiveness of one of the last-line antibiotics for treating multidrug-resistant Gram-negative infections. Although wildlife is increasingly recognized as a reservoir of mobile antimicrobial resistance genes, its role in the emergence and dissemination of novel plasmid-mediated colistin resistance (mcr) genes remains poorly understood. Objectives: This study aimed to characterize two distinct mcr-carrying E. coli isolates identified in Spanish wildlife. Methods: Among 807 faecal samples from healthy wild animals screened, two mcr-positive E. coli isolates were identified. Genomic characterization included whole-genome sequencing, plasmid analysis, and functional assays, followed by heterologous expression and lipid A characterization by Ultra-High-Performance Liquid Chromatography coupled with High-Resolution Mass Spectrometry (UHPLC-HRMS). Results: Analysis of the two mcr-positive E. coli isolates revealed the first mcr-1-positive isolate from a wild boar (Sus scrofa) in Extremadura, Spain, carrying mcr-1 on a 33.3-kb conjugative IncX4 plasmid, while the isolate recovered from an Iberian lynx harbored mcr-13, a novel plasmid-borne mcr-like gene encoding a putative phosphoethanolamine (pEtN) transferase on a 163-kb non-conjugative plasmid. MCR-13 showed 82% amino acid identity with MCR-10, increased colistin MIC two-fold in a susceptible E. coli host, and mediated phosphoethanolamine modification of lipid A, although to a lower extent than MCR-1. Conclusions: The co-occurrence of established (mcr-1) and a novel mcr-like gene mcr-13, further supports the role of wildlife as a potential reservoir of emerging resistance genes and highlights the value of including wildlife in One Health surveillance programs. Full article

4′-Hydroxymethoxychalcones represent structurally diverse chalcone derivatives that are attractive substrates for microbial functionalization; however, the impact of methoxy substitution position on their cascade biotransformation by fungi remains poorly understood. In this study, three regioisomeric 4′-hydroxymethoxychalcones, featuring ortho-, meta-, or para-methoxy groups on ring B, were transformed using eight entomopathogenic fungal strains belonging to the genera Beauveria, Isaria, and Metarhizium. Metabolic profiles were monitored over a 10-day period using ultra-high-performance liquid chromatography coupled with diode-array detection (UHPLC-DAD), and the structures of the major products were elucidated primarily by one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy and further supported by high-resolution electrospray ionization quadrupole time-of-flight mass spectrometry (HR-ESI-QTOF-MS). The investigated microorganisms catalyzed multistep transformations encompassing the reduction of the α,β-unsaturated carbonyl system, methylglucosylation, O-demethylation, and the formation of secondary polar metabolites. Although ene-reduction constituted the predominant initial reaction for all substrates, the relative distribution of subsequent metabolites varied depending on both the fungal strain and, to a lesser extent, the position of the methoxy group. The ortho-methoxy derivative exhibited the highest propensity for O-demethylation; the meta-substituted substrate generated the most heterogeneous secondary metabolite profiles, whereas the para-methoxy analogue showed the most consistent accumulation of methylglucosylated dihydrochalcones. These findings indicate that methoxy substitution position does not alter the common core biotransformation pathway, but can modulate the relative efficiency of individual steps and the extent of secondary metabolism. Full article

Objective: Siweixizangmaoru decoction (SXD), a classical Tibetan prescription documented in the medical text Four Medical Tantras, has shown therapeutic activity in experimental rheumatoid arthritis (RA). However, its candidate active constituents and underlying mechanisms remain unclear. Methods: In this study, serum-absorbed constituents following SXD administration were profiled using ultra-high-performance liquid chromatography coupled with quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS), and network pharmacology was employed to identify core targets and candidate active constituents of SXD against RA. Candidate active constituents were further screened using cell-based assays, and the selected constituents were quantified using HPLC fingerprint analysis. Both in vivo (CIA rat model) and in vitro (RAW264.7 pyroptosis model) systems were used to investigate the pharmacological effects and mechanisms of SXD. Results: A total of 11 absorbed constituents were identified in the serum of SXD-treated rats, and four preliminary candidate active constituents, including chebulagic acid, kaempferol, gentiopicroside, and berberine, were screened. The combined in vivo and in vitro results showed that SXD attenuated RA progression and reduced inflammatory cytokine levels in rat serum and cell culture supernatants. At the molecular level, SXD increased Pol β expression and reduced DNA damage markers, cytosolic dsDNA accumulation, and cGAS/STING-, NF-κB-, and NLRP3-associated signaling. Pol β knockdown partially reduced the effects of SXD. Conclusions: These findings support the partial involvement of Pol β-associated processes in the anti-arthritic effects of SXD. Full article