Search Results (950)

The disruption of mitochondrial homeostasis is a trigger for insulin resistance. The loss of N-acetyltransferase 1 (Nat1) function, an insulin-sensitivity gene, contributes to mitochondrial dysfunction and insulin resistance. Carnosic acid (CA), a diterpene derived from rosemary, has demonstrated an anti-insulin-resistance effect. This study hypothesized that CA protects against TNF-α-induced insulin resistance in 3T3-L1 adipocytes by regulating mitochondrial dynamics, biogenesis, and function via Nat1. 3T3-L1 adipocytes were pretreated with CA for 12 h, followed by co-treatment with TNF-α for an additional indicated duration. Results showed that treatment of 3T3-L1 adipocytes with TNF-α decreases mitochondrial membrane potential (MMP) and PGC-1α protein levels and alters mitochondrial fission/fusion dynamics. Pretreatment with CA improved these effects. In parallel, CA prevented the TNF-α-induced reduction in Nat1 protein and improved insulin signaling by suppressing the phosphorylation of insulin receptor substrate-1 (IRS-1) at serine³⁰⁷, while restoring the phosphorylation of IRS-1 at tyrosine⁶²⁸ and Akt. Moreover, transfection with Nat1 siRNA inhibited the protective effect of CA against TNF-α-induced reductions in MMP, PGC-1α, and insulin signaling. In conclusion, CA ameliorated TNF-α-induced insulin resistance by reducing mitochondrial dysregulation by Nat1. Full article

Wound dressings play a crucial role in promoting tissue regeneration while protecting damaged tissue from microbial infections. The aim of this study is to produce antimicrobial PVA-chitosan membranes for wound dressing applications using Stevia rebaudiana Bertoni leaf extract (stevia) as a natural bioactive agent. Although widely recognized as a natural sweetener, stevia contains a high concentration of diterpene glycosides, particularly stevioside and rebaudioside A, together with phenolic compounds that contribute to its biological activities. Therefore, stevia was first evaluated against selected microorganisms and demonstrated effective antimicrobial activity. PVA-chitosan (P/Ch) membranes were prepared by solvent casting method by incorporating different amounts of stevia (P/Ch, P/Ch@20, P/Ch@40, and P/Ch@60). The antimicrobial activity of stevia was also successfully maintained in P/Ch membranes. Good antibacterial activity was observed against Bacillus subtilis and Escherichia coli, whereas the antifungal activity against Candida albicans was comparatively modest. Contact surface analysis showed complete bactericidal activity in Gram-negative and spore-forming bacteria. The cytocompatibility of the membranes was investigated by MTT assay. All formulations maintained a high cell viability (>80%) while the P/Ch@40 membrane increased the metabolic activity to above 100% at higher extract concentrations. In conclusion, stevia-incorporated membranes exhibited high antimicrobial activity, acceptable characteristic properties, and good cytocompatibility, suggesting that they are promising alternative biomaterials for tissue engineering applications. Full article

Background/Objectives: Plant secondary metabolites remain an invaluable source of novel antibacterial phytochemicals in the fight against antibiotic resistance. The medicinal plant Solidago gigantea Ait. (giant goldenrod) is an invasive species in Europe and represents an abundant, yet largely underexplored reservoir of such bioactive compounds. The primary aim of this study was to perform a non-targeted, effect-directed screening, detection, bioassay-guided isolation, structure elucidation, and microbiological assessment of the antibacterial constituents present in the inflorescences of S. gigantea. Methods: Thin-layer chromatography coupled with direct bioautography (TLC–DB) assay using Bacillus subtilis was utilized for the non-targeted, effect-directed analysis of antibacterial components and the evaluation of in vitro antibacterial activity. Successive preparative flash column chromatography, semi-preparative reversed-phase high-performance liquid chromatography (RP-HPLC), and thin-layer chromatography–mass spectrometry (TLC–MS) were employed for the bioassay-guided fractionation and isolation. The structures of the isolated compounds were elucidated using one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy and high-resolution tandem mass spectrometry (HRMS/MS). The presence of known antibacterial compounds was established via reversed-phase ultra-high-performance liquid chromatography coupled with high-resolution electrospray ionization tandem mass spectrometry (RP-UHPLC–HR-ESI-MS/MS). Results: Two previously undescribed cis-clerodane diterpenoids, the isomeric solidagoic acid L (1) and solidagoic acid M (2), were isolated, identified, and characterized from the ethyl acetate extract of S. gigantea inflorescences. Both compounds exhibited in vitro antibacterial activity against the Gram-positive B. subtilis, confirmed via TLC–DB. In addition, 23 known compounds with antibacterial activity, including 17 clerodane diterpenes, four hydroxylated polyunsaturated fatty acids, and two unsaturated monoacylglycerols, were detected. All of these are reported for the first time in the inflorescences of this plant species. Conclusions: With further optimization, the isolated compounds may represent promising leads for antibacterial drug development. Our findings demonstrate the potential of non-targeted, bioassay-guided approaches for the discovery of novel plant-derived bioactive natural products. Full article

Polyploidization frequently rewires plant metabolism, leading to increased biomass and altered metabolic profiles. This makes it a promising strategy for crop improvement and breeding. However, the mechanism underlying this metabolic reprogramming remains largely unknown. In this study, we generated three stable autotetraploid Nicotiana sylvestris lines through colchicine treatment of diploids followed by continuous selection. Comparative metabolomic and transcriptomic analysis revealed 467 and 167 differential accumulated metabolites, as well as 587 and 154 differentially expressed genes between tetraploids and diploids in leaves and flowers, respectively. The increased expression levels of Calvin–Benson cycle genes and the elevated contents of pyruvate and glyceraldehyde-3-phosphate indicated enhanced photosynthetic carbon assimilation in tetraploid plants. Notably, the amounts of diterpenoids, such as cembratrienediol (CBT-diol) and cis-abienol, increased dramatically in tetraploids, whereas sucrose, the major product of photosynthesis, was markedly depleted. Consistent with this, the expression levels of the methylerythritol phosphate pathway and diterpene biosynthesis genes were upregulated, while sucrose phosphate synthase was downregulated in autotetraploid plants. These results suggest that polyploidization enhanced carbon assimilation and redirects the increased metabolic flux towards diterpenoid biosynthesis, rather than carbohydrate metabolism. Our findings provide new insight into the metabolic switch orchestrated by polyploidization, establish a mechanistic framework for polyploidy-driven metabolic innovation, and highlight autopolyploidization as a promising strategy for metabolic engineering and crop improvement. Full article

Gibberellic acids (GAs) are a class of tetracyclic diterpene carboxylic acid compounds produced by green plants, fungi, and bacteria, which have a wide range of applications in agricultural production and food ingredients processing. Owing to the continuously growing market demand, enhancing GA yield has become imperative. The biosynthesis of GAs is a multi-enzymatic synergistic process that can be enhanced through genetic and metabolic engineering strategies. In this review, we first summarize recent advances in GA production by Fusarium fujikuroi. We then highlight key metabolic engineering strategies, including biosynthetic pathway engineering, cluster-specific channeling of geranylgeranyl diphosphate biosynthesis, cofactor engineering, as well as regulatory mechanisms involving nitrogen modulation and histone modification. Finally, we discuss promising approaches for constructing high-efficiency microbial cell factories, such as implementation of the CRISPR/Cas9 system, the application of strong promoters, the development of target-specific technologies for small molecules, and the employment of genome-scale metabolic models. Recent metabolic engineering efforts have achieved GA3 titers of up to 3.16 g/L through multi-target nitrogen regulation strategies, highlighting the potential for further yield improvement. Full article

Background: Rosmarinus officinalis L. is a medicinally important aromatic plant rich in bioactive secondary metabolites with diverse therapeutic properties. This study aimed to characterize the phytochemical profile of R. officinalis leaf extracts, isolate carnosic acid as a major bioactive diterpene, and evaluate its biological activities. Methods: Leaf extracts were prepared using solvents of increasing polarity and analyzed by phytochemical screening and UHPLC/QTOF-MS. Carnosic acid was isolated by thin-layer chromatography and assessed for antibacterial, antibiofilm, antioxidant, anti-inflammatory, antidiabetic, and antiproliferative activities using in vitro assays. Expression of apoptosis-related genes was also investigated. Results: Methanolic and ethanolic extracts exhibited the highest abundance of phenolic compounds and secondary metabolites, whereas the hexane extract showed lower phytochemical content. UHPLC/QTOF-MS identified seven major metabolites, including phenolic acids, flavonoids, and abietane-type diterpenes. Purified carnosic acid demonstrated potent antibacterial activity (MIC: 10–23 μg/mL) and inhibited biofilm formation by up to 90%. Strong antioxidant activity was observed, with DPPH and ABTS radical-scavenging IC₅₀ values of 125 and 130 μg/mL, respectively. The compound also exhibited notable anti-inflammatory activity and markedly inhibited α-amylase and α-glucosidase activities. Furthermore, carnosic acid exhibited dose-dependent antiproliferative activity against MCF-7, HepG2, and MCF-10A cells, reducing cell viability to 10.8%, 16.9%, and 70.4 ± 1.8%, respectively, at 250 μg/mL, with corresponding IC₅₀ values of 28.3, 37.8, and >250 μg/mL, respectively. Gene expression analysis revealed upregulation of BAX and downregulation of BCL2, indicating activation of mitochondrial-mediated apoptosis. Conclusions:R. officinalis leaves represent a valuable source of multifunctional phytochemicals, particularly carnosic acid. Its broad-spectrum biological activities and apoptosis-inducing potential support its promising application in pharmaceutical, nutraceutical, and biomedical fields. Full article

Mass spectrometry-based lipidomics has created new opportunities to investigate the role of lipids in coffee quality formation and stability across the production chain. Coffee lipids contribute to flavor precursor formation, aroma release, mouthfeel, and storage behavior, but their molecular remodeling during maturation, processing, roasting, and storage remains insufficiently integrated. This review summarizes recent progress in lipidomics methodologies relevant to coffee research, with emphasis on sample preparation, mass spectrometry platforms, data analysis, and the strengths and limitations of current lipid annotation strategies. It further examines how lipid profiles change during bean maturation, how they differ among coffee species and varieties, and how they are reshaped by postharvest processing, roasting, and storage. However, it is important to note that most of these associations are currently correlational rather than causal; direct evidence linking specific lipid species to particular sensory attributes remains limited. Existing studies suggest that lipid composition, rather than total lipid content alone, is more informative for understanding coffee quality differences and for identifying candidate markers associated with origin, processing method, roasting degree, and storage conditions. In particular, alterations in glycerolipids, glycerophospholipids, fatty acids, diterpenes, and other minor lipid constituents are increasingly associated with lipid oxidation, thermal degradation, and flavor-related transformations in coffee. However, current evidence is still limited by incomplete structural annotation, isomeric ambiguity, platform dependence, and the frequent gap between statistical discrimination and mechanistic validation. Future work integrating high-resolution mass spectrometry, ion mobility, targeted quantification, stable isotope tracing, sensory analysis, and multi-omics approaches will be essential to improve marker reliability and to clarify the functional roles of coffee lipids. Overall, lipidomics provides a promising framework for linking molecular composition with coffee quality control, traceability, and process optimization, although substantial work is still needed to establish mechanistic links to flavor formation. Full article

Distillation is widely used for essential oils extraction, and distillation time (DT) influences the quality and quantity of oils. This study presents the effects of 14 DTs (1, 3, 5, 10, 20, 40, 80, 120, 160, 200, 240, 280, 360, and 480 min) on leaf oils from Thuja occidentalis L., aiming to maximise the yield and modulate chemical profiles. Also, a safety assessment of T. occidentalis oils obtained at different DTs was conducted based on thujone levels under International Fragrance Association (IFRA) guidelines. Oil yield varied with DT, reaching a maximum at 40–80 min (0.54 ± 0.04% and 0.59 ± 0.02%, respectively). Monoterpenes (sabinene, fenchone, and thujone) decreased with prolonged DT, whereas higher molecular weight compounds, including sesquiterpenes (caryophyllene) and diterpenes (hibaene and rimuene) increased. Principal component analysis (PCA) grouped samples into three stages, early (1–10 min), mid (20–80 min), and late (120–480 min), with clear compositional separation (PC1: 68.4%, PC2: 11.8%). As DT increased, the fragrance profile progressively shifted from monoterpene-rich characteristics in the early-stage oils to more persistent aromas associated with sesquiterpenes (caryophyllene, α-cadinol, and α-eudesmol) and diterpenes (hibaene and rimuene) in the late-stage oils. Safety assessment revealed that early-stage oils contained high thujone levels (67.19–71.88%), limiting their allowable use. In contrast, prolonged DTs (≥200 min) reduced thujone content, increasing permissible usage across multiple IFRA categories. Overall, DT significantly influences the oil yield, chemical composition, and regulatory applicability of T. occidentalis oils, with extended distillation enhancing formulation flexibility in cosmetic and fragrance applications. Full article

The composition of low-polarity extracts obtained by sequential extraction of the aerial parts of Rhododendron adamsii Rehd. with hexane and methyl tert-butyl ether (MTBE) was investigated using GC-MS. The hexane extract was dominated by non-polar components: squalene, n-alkanes (nonacosane, hentriacontane), sesquiterpenes (trans-nerolidol, spathulenol, β-farnesene), and β-sitosterol. The subsequent MTBE extract was enriched in more polar lipids, primarily free triterpenic acids (ursolic and oleanolic acids). A critical finding was the complete absence of diterpene grayanotoxins in all tested extracts, confirming the safety of the non-polar extraction approach. In bioactivity assays, the total hexane extract demonstrated potent inhibitory activity against the SARS-CoV-2 main protease (3CLpro) with IC₅₀ values of 0.0125–0.025 mg/mL, only one order of magnitude higher than the reference inhibitor disulfiram. Fractionation revealed that the activity was distributed among free acids, bound acids, and the unsaponifiable residue, indicating a multicomponent mechanism. Importantly, none of the samples inhibited HIV-1 protease (IC₅₀ > 0.1 mg/mL), demonstrating selectivity for the cysteine protease 3CLpro over the aspartyl protease of HIV-1. These results highlight that sequential non-polar extraction of R. adamsii provides a grayanotoxin-free lipophilic complex with selective anti-SARS-CoV-2 protease activity, paving the way for bioactivity-guided identification of individual inhibitors. Full article

An unreported bicyclic sesquiterpene acid, verruculosic acid (1), was isolated together with the previously reported labdane diterpenes, (+)-agathic acid (2a) and hypoxyterpenoid A (2b), one 3-nor-2,3-seco-labdane, penioxalicin (3), and 5-carboxyphthalide (4), from a sea grass-associated fungus, Penicillium verruculosum KUFA1509. The structures of the isolated compounds were elucidated by detailed analyses of 1D and 2D NMR and HRMS data. The absolute configurations of the stereogenic carbons in 1 and 2a were established by X-ray crystallography. The crystal structure of 2a, which was obtained for the first time, was used to prove its structure and confirm its stereochemistry. The crystal structure of 3 was also obtained; however, the value of its flack parameter does not allow us to determine the absolute configuration. Compound 2b exhibited stronger inhibitory activity than the positive control, diclofenac sodium, against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages, while 1 and 2a were slightly less active than the positive control. In contrast, 3 exhibited much weaker activity than 2a. Compounds 1–4 were also assayed for antibacterial activity against reference and multidrug-resistant strains, but none exhibited antibacterial activity against the tested strains. Thus, the labdane skeleton could be considered as a potential scaffold for the development of anti-inflammatory agents through NO inhibition. Full article

The genus Salvia L. represents one of the most pharmacologically significant groups within the Lamiaceae family. This study investigates the phytochemical profiles and biological activities of six Salvia species native to Türkiye (S. dorystaechas B.T.Drew, S. sclarea L., S. glutinosa L., S. tomentosa Mill., S. argentea L., and S. aethiopis L.) to scientifically validate their extensive use in Turkish traditional medicine. Phytochemical characterization was performed using Liquid Chromatography–High-Resolution Mass Spectrometry (LC-HRMS), while biological potential was evaluated through antioxidant (DPPH), antimicrobial (MIC), and cytotoxicity (MTT on NIH/3T3 cells) assays. Among the taxa, S. dorystaechas exhibited the most potent antioxidant activity, with IC₅₀ values of 0.090 mg/mL (infusion) and 0.072 mg/mL (ethanolic), which strongly correlated with high total phenolic contents (111.50 and 125.55 mg GAE/g, respectively). This species may also serve as a potential source of bioactive compounds. Antimicrobial screenings against pathogenic bacteria and Candida spp. demonstrated modest inhibitory effects, with MIC values ranging from 625 to >5000 µg/mL. Safety profiling indicated that the ethanolic extract of S. tomentosa showed the lowest cytotoxicity (IC₅₀ 562.37 ± 49.50 µg/mL) among the tested samples, which nonetheless indicates a relatively narrow therapeutic window. LC-HRMS profiling revealed the presence of flavonoids and phenolic diterpenes, such as carnosol and rosmanol, providing a chemical rationale for the observed moderate activities. Consequently, rather than direct systemic pharmacological agents, these findings suggest that the studied Salvia species could serve as preliminary botanical sources for the isolation of specific secondary metabolites or for restricted topical applications. Full article

This review aims to comprehensively examine spent coffee grounds (SCGs) as a sustainable source of antioxidant and immunomodulatory bioactives, with a specific focus on their capacity to modulate membrane-level signaling through ion channels and G-protein-coupled receptors (GPCRs) in the context of lifestyle-related chronic diseases. SCGs, the major solid by-product of coffee brewing, represent an underutilized yet highly abundant source of bioactive compounds, including chlorogenic acids, phenolic acids, melanoidins, diterpenes, and residual alkaloids. Lifestyle-related chronic diseases, including type 2 diabetes, obesity, cardiovascular disease, and chronic inflammatory disorders, are increasingly recognized as immunometabolic conditions driven by persistent low-grade inflammation, redox imbalance, and dysregulated membrane signaling. This review synthesizes current evidence demonstrating that bioactives contained in SCG extracts exert antioxidant and immunomodulatory effects that extend beyond radical scavenging. Crucially, these compounds also act as modulators of membrane-level signaling, representing a mechanistic perspective that has not been previously integrated for SCGs in the context of chronic disease. The different extraction methodologies and the obtained results are evaluated with the aim to identify the most effective experimental approach and extraction conditions. The paper also discusses how SCG compounds regulate redox-sensitive ion channels (including calcium channels, TRP channels, and potassium channels), and key GPCR pathways (such as GPR120, GPR43, and adenosine receptors), thereby influencing immune cell activation, cytokine production, insulin signaling, and metabolic inflammation. Particular attention is given to the role of microbial fermentation and enzymatic processing in enhancing SCG bioavailability, generating postbiotic metabolites that further engage GPCR–ion channel crosstalk. By integrating extraction approaches, antioxidant chemistry, immunology, membrane signaling, and nutritional metabolism, this review positions SCG as a sustainable functional ingredient capable of restoring immune tolerance and metabolic homeostasis. These insights support the valorization of SCGs within the circular economy framework and highlight their potential application in next-generation immunonutrition strategies for chronic disease prevention and management. Full article

Oleoresins are complex natural lipophilic matrices traditionally analyzed using chromatographic techniques that require extensive sample preparation, derivatization, and authentic standards. Amazonian oleoresins from Copaifera and Eperua species (Fabaceae) represent valuable bioresources with recognized pharmacological potential, largely attributed to diterpenoids such as copalic and hardwickiic acids, as well as bioactive sesquiterpenes, including the cannabinoid β-caryophyllene. In this study, we present a proof-of-concept application of Direct Analysis in Real Time coupled with High-Resolution Mass Spectrometry (DART-HRMS) as a rapid, direct, and environmentally friendly approach for chemical fingerprinting and semi-targeted screening of the two most important amazonian oleoresins from these two genera: Eperua oleifera and Copaifera multijuga. Analyses were performed using a Q Exactive Orbitrap coupled to a DART ion source under optimized conditions. Hardwickiic acid was used as a model compound for method optimization, with optimal performance achieved at 200 °C and 100 V, yielding stable signal intensities (CV < 10%) and high mass accuracy (<1 ppm). The method enabled reproducible detection of diterpenic acids in both oleoresins, allowing differentiation of their chemical profiles and assessment of short-term stability under ambient conditions. In addition to diterpenes, free fatty acids were also detected, expanding the compositional characterization of these matrices. Compound annotation was performed based on accurate mass measurements and literature comparison, corresponding to Level 5 confidence according to established metabolomics criteria. Although the absence of chromatographic separation limits isomer discrimination and absolute quantification, DART-HRMS provides a rapid and solvent-free strategy for chemical fingerprinting and preliminary characterization of oleoresins. This approach aligns with Green Chemistry principles and shows strong potential as a screening and triage tool for quality control, chemotaxonomic studies, and sustainable valorization of Amazonian natural products. Full article

Schistosomiasis remains one of the most significant neglected tropical diseases (NTDs) worldwide, sustained by the complex biology of Schistosoma species and the host’s immunopathological responses to tissue-trapped eggs. Despite decades of reliance on praziquantel (PZQ) as the sole chemotherapeutic option, major limitations persist, including its lack of activity against juvenile worms, incomplete protection against reinfection, and concerns regarding emerging tolerance. These challenges, together with persistent hotspots of transmission and uneven global progress toward disease elimination, underscore the urgent need for alternative or complementary therapies. Plant-derived terpenes have emerged as promising antischistosomal candidates due to their structural diversity, broad-spectrum bioactivity, and favourable safety profiles. Evidence from in vitro and in vivo studies demonstrates that monoterpenes, sesquiterpenes, diterpenes, triterpenes, and triterpenoid saponins exert multimodal effects on Schistosoma, including tegumental disruption, interference with metabolic and redox pathways, inhibition of oviposition, and modulation of host immune and fibrotic responses. Advances in mechanistic studies, supported by omics and computational approaches, further highlight their potential as leads for drug development. Additionally, nano-enabled delivery systems offer strategies to overcome pharmacokinetic limitations and enhance therapeutic performance. This review integrates current knowledge on schistosome biology, treatment challenges, and the growing evidence supporting terpenoids as viable components of a diversified antischistosomal therapeutic arsenal. Full article

Dementia, including Alzheimer’s disease (AD), represents one of the most pressing public health challenges of the 21st century, affecting more than 55 million individuals worldwide, with projections reaching 139 million by 2050. Current pharmacological treatments offer limited efficacy and significant side effects, driving intense interest in plant-derived natural products as both preventive and therapeutic agents. This review synthesizes preclinical and clinical evidence for key phytochemical classes, including polyphenols, phenolic acids, flavonoids, terpenoids, and alkaloids, in the context of dementia and age-related cognitive decline. Molecular mechanisms are examined in detail, including effects on antioxidant defense and redox homeostasis, suppression of neuroinflammation, and enhancement of synaptic plasticity and neurotransmission. Despite promising preclinical and epidemiological evidence, most clinical trials remain limited in scale and duration and provide mixed results on the efficacy of using phytochemicals for cognitive health. Among the compounds with the most consistent clinical support are the ginkgo diterpene extract EGb 761, saffron carotenoids, curcumin, and rosmarinic acid. A dedicated section addresses the emerging evidence for aromatherapy as a non-pharmacological intervention for behavioral and cognitive symptoms of dementia. Future directions include strategies to improve bioavailability of phytochemicals, the utilization of aromatherapy together with oral supplements, and the need for larger randomized controlled trials using well-characterized and reproducibly manufactured formulations and purified active compounds. Priority areas for future investigation include resolving pharmacokinetic barriers to central nervous system (CNS) delivery, standardizing herbal product composition, and conducting adequately designed clinical trials in well-defined patient populations. Full article