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The Jurassic relict Royal fern, Osmunda regalis L., is widely distributed across temperate zones in the Northern and Southern hemispheres. Even though this species has been utilised for centuries as a medicinal plant, its phytochemical composition mainly remains unknown. As part of our ongoing research to identify potential lead compounds for future anticancer drugs, 17 natural products were characterised from the aerial parts of Osmunda regalis L. Fifteen of these compounds were identified in this species for the first time, including the six previously undescribed compounds kaempferol 3-O-(2''-O-(2'''-α-rhamnopyranosyl)-ß-glucopyranosyl)-ß-glucopyranoside, quercetin 3-O-(2''-O-(2'''-α-rhamnopyranosyl)-ß-glucopyranosyl)-ß-glucopyranoside, kaempferol 3-O-(2''-O-(2'''-α-rhamnopyranosyl-6'''-O-(E)-caffeoyl-)-ß-glucopyranosyl)-ß-glucopyranoside, 3-methoxy-5-hydroxy-4-olide, 4-hydroxy-3-(3'-hydroxy-4'-(hydroxyethyl)-oxotetrafuranone-5-methyl tetrahydropyranone, and 4-O-(5-hydroxy-4-oxohexanoyl) osmundalactone. The molecular structures were determined by combining several 1D and 2D NMR experiments, circular dichroism spectroscopy, and HRMS. Determination of cytotoxicity against AML MOLM-13, H9c2, and NRK cell lines showed that two isolated lactones exhibited significant cytotoxic activity.
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Productos Biológicos , Productos Biológicos/química , Productos Biológicos/farmacología , Humanos , Helechos/química , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Espectroscopía de Resonancia MagnéticaRESUMEN
INTRODUCTION: European aspen (Populus tremula L.) knotwood contains large amounts of polyphenolic metabolites, mainly flavonoids, and can be considered as a promising industrial-scale source of valuable bioactive compounds. Valorization of knotwood extractives requires detailed information on their chemical composition and a relevant analytical methodology. OBJECTIVE: This study proposes combined analytical strategy for non-targeted screening and identification of polyphenolic plant metabolites and is aimed at comprehensive characterization of knotwood extractives. MATERIALS AND METHODS: Aspen knotwood acetone extract with determined antioxidant activity was an object of the study. Two-dimensional NMR spectroscopy with Structure Elucidator expert system was used for preliminary search of major components and specific structures. Liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS) with data-dependent MS/MS spectra acquisition was used as a complementary technique providing molecular-level characterization and identification of the detected metabolites. RESULTS: Twenty-eight phenolic metabolites were found and identified. Among them, flavonoids, aromadendrin and naringenin, as well as their glycosylated derivatives (mainly O-glucosides) and methyl ethers, dominated. Taxifolin and its 7-O-glucoside were detected as minor components. Other detected compounds are represented by p-coumaric acid and its rutinoside and small amounts of glycosylated ferulic acid. Nineteen of the detected compounds were discovered in aspen knotwood for the first time. The results were confirmed by preparative isolation of individual compounds and NMR studies. CONCLUSION: The proposed analytical strategy based on 2D NMR and HPLC-HRMS can be considered a powerful tool in the analysis of plant extractives and allowed for the identification and semi-quantification of a large number of polyphenols in aspen knotwood.
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Metabolomics has been widely applied in human diseases and environmental science to study the systematic changes of metabolites over diverse types of stimuli. NMR-based metabolomics has been widely used, but the peak overlap problems in the one-dimensional (1D) NMR spectrum could limit the accuracy of quantitative analysis for metabolomics applications. Two-dimensional (2D) NMR has been applied to solve the 1D NMR overlap problem, but the data processing is still challenging. In this study, we built an automatic approach to process the 2D NMR data for quantitative applications using machine learning approaches. Partial least square discriminant analysis (PLS-DA), artificial neural network classification (ANN-DA), gradient boosted trees classification (XGBoost-DA), and artificial deep learning neural network classification (ANNDL-DA) were applied in combination with an automatic peak selection approach. Standard mixtures, sea anemone extracts, and mouse fecal samples were tested to demonstrate the approach. Our results showed that ANN-DA and ANNDL-DA have high accuracy in selecting 2D NMR peaks (around 90 %), which have a high potential application in 2D NMR-based metabolomics quantitively study, while PLS-DA and XGBoost-DA showed limitations in either data variation or overfitting. Our study built an automatic approach to applying 2D NMR data to routine quantitative analysis in metabolomics.
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Aprendizaje Automático , Espectroscopía de Resonancia Magnética , Metabolómica , Metabolómica/métodos , Animales , Ratones , Espectroscopía de Resonancia Magnética/métodos , Redes Neurales de la Computación , Análisis de los Mínimos Cuadrados , Análisis Discriminante , Heces/químicaRESUMEN
The present study describes an eco-friendly NBS-assisted regioselective synthesis of new 5-acylfunctionalized 5-acylfunctionalized 2-(1H-pyrazol-1-yl)thiazoles by condensation of 3,5-dimethyl-1H-pyrazole-1-carbothioamide with unsymmetrical 1,3-diketones under solvent-free conditions. The structural elucidation of the newly synthesized compounds was accomplished using various spectroscopic techniques viz. FTIR, NMR and mass spectrometry. All the newly synthesized compounds were examined for their inâ vitro antimicrobial potential against both pathogenic gram positive and gram negative bacterial and fungal species as well as anthelmintic activity against Pheretima posthuma earthworms. The results of antimicrobial activity revealed that all tested compounds 3 a-j showed excellent antimicrobial potential particularly against S. aureus. It was also observed that compounds 3 e and 3 i (MIC=62.5 µg/mL) showed greater potency against E. coli, whereas compounds 3 a and 3 h (MIC=50 µg/mL and 62.5 µg/mL) demonstrated better activity against P. aeruginosa and compound 3 i (MIC=62.5 µg/mL) exhibited superior activity against S. pyogenus when compared to standard drug Ampicillin (MIC=100µg/mL). Compound 3 e and 3 j revealed remarkable antifungal and anthelmintic activities. To find out binding interactions of target compounds with target proteins and pharmacokinetic parameters of the compounds, in silico investigations involving molecular docking studies and ADMET predictions were also performed.
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We have synthesized a one-pot, three-component pyran-based fluorescence chemosensor using onion extract as a green catalyst. The confirmed structure of the 1:2 binding of receptor SPR-2-picric acid adduct revealed that the pyran-based receptor accommodated two guest picric acid molecules through non-covalent interactions. UV-Vis and fluorescence spectroscopy show high selectivity and sensitivity towards picric acid. The 1D/2D NMR and Job's plot analysis show the complexation and stoichiometric binding of the receptor SPR-2 with picric acid are 1:2. The 1H NMR spectral studies confirm that the formation of receptor SPR-2-picric acid adduct via weak hydrogen bonding. The cooperativity of the receptor SPR-2-picric acid adduct shows negative cooperativity due to the weak hydrogen bonding of receptor SPR-2 and picric acid. Further, the density functional theory (DFT) confirmed the molecular level interaction of the SPR-2 and receptor SPR-2-Picric acid adduct. The receptor was effectively used to assess picric acid concentrations in real water samples.
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From the root barks of a Central African tree Millettia dubia De Wild. (Fabaceae), ten previously undescribed oleanane-type glycosides were isolated by various chromatographic protocols. Their structures were elucidated by spectroscopic methods, mainly 2D NMR experiments and mass spectrometry, as mono- and bidesmosidic glycosides of mesembryanthemoidigenic acid, hederagenin and oleanolic acid. The stimulation of the sweet taste receptor TAS1R2/TAS1R3 by these glycosides was evaluated, and structure/activity relationships were proposed. Two of them showed an agonist effect on TAS1R2/TAS1R3.
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Glicósidos , Ácido Oleanólico , Receptores Acoplados a Proteínas G , Ácido Oleanólico/química , Ácido Oleanólico/farmacología , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/aislamiento & purificación , Glicósidos/química , Glicósidos/farmacología , Glicósidos/aislamiento & purificación , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Relación Estructura-Actividad , Estructura Molecular , Humanos , Millettia/química , Corteza de la Planta/química , Raíces de Plantas/químicaRESUMEN
While syringyl units are the most abundant monolignols in hardwood lignin, their phenolic (i.e. hydroxyl) end group concentration has not been measured. In two uniformly 13C-enriched young hardwoods, from beech and oak, the syringyl units were quantitatively investigated by advanced solid-state 13C NMR. Small signals of OH-terminated syringyl units were resolved in spectrally edited two-dimensional 13C-13C NMR spectra of the two hardwoods. Their distinct peak positions predicted based on literature data were validated via the abundant OH-terminated syringyl units in hydrolyzed 13C-beechwood. In a two-dimensional 13C-13C exchange spectrum with diagonal-ridge suppression, a well-resolved peak of phenolic syringyl units was observed at the characteristic C-H peak position of syringyl rings, without significant overlap from guaiacyl peaks. Accurate 13C chemical shifts of regular and end-group syringyl units were obtained. Through spectrally edited 2D NMR after 1H inversion recovery, phenols of condensed tannin complexed with arginine were carefully analyzed and shown to overlap minimally with signals from phenolic syringyl units. The local structure and resulting spin dynamics of ether (chain) and hydroxyl (end-group) syringyl units are nearly the same, enabling quantification by peak integration or deconvolution, which shows that phenolic syringyl end groups account for 2 ± 1 % of syringyl units in beechwood and 5 ± 2 % in oakwood. The observed low end-group concentration needs to be taken into account in realistic molecular models of hardwood lignin structure.
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A protocol for efficiently identifying ligands directly interacting with a target protein in complex extracts of medicinal herbs was proposed by combining an adapted 2D perfect-echo Carr-Purcell-Meiboom-Gill heteronuclear single quantum correlation (PE-CPMG HSQC) spectrum with metabolomic analysis. PE-CPMG HSQC can suppress the signal interference from the target protein, allowing more accurate peak quantification than conventional HSQC. Inspired from untargeted metabolomics, regions of interest (ROIs) are constructed and quantified for the mixture or complex extract samples with and without a target protein, and then a binding index (BI) of each ROI is determined. ROIs or corresponding peaks significantly perturbed by the presence of the target protein (BI ≥1.5) are detected as differential features, and potential binding ligands identified from the differential features can be equated with bioactive markers associated with the 'treatment' of the target protein. Quantifying ROI can inclusively report the ligand bindings to a target protein in fast, intermediate and slow exchange regimes on nuclear magnetic resonance (NMR) time scale. The approach was successfully implemented and identified Angoroside C, Cinnamic acid and Harpagoside from the extract of Scrophularia ningpoensis Hemsl. as ligands binding to peroxisome proliferator-activated receptor γ. The proposed 2D NMR-based approach saves excess steps for sample processing and has a higher chance of detecting the weaker ligands in the complex extracts of medicinal herbs. We expect that this approach can be applied as an alternative to mining the potential ligands binding to a variety of target proteins from traditional Chinese medicines and herbal extracts.
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Metabolómica , Plantas Medicinales , Ligandos , Metabolómica/métodos , Plantas Medicinales/química , PPAR gamma/metabolismo , Extractos Vegetales/química , Extractos Vegetales/análisis , Unión ProteicaRESUMEN
Plant metabolomics, a rapidly advancing field within plant biology, is dedicated to comprehensively exploring the intricate array of small molecules in plant systems. This entails precisely gathering comprehensive chemical data, detecting numerous metabolites, and ensuring accurate molecular identification. Nuclear magnetic resonance (NMR) spectroscopy, with its detailed chemical insights, is crucial in obtaining metabolite profiles. Its widespread application spans various research disciplines, aiding in comprehending chemical reactions, kinetics, and molecule characterization. Biotechnological advancements have further expanded NMR's utility in metabolomics, particularly in identifying disease biomarkers across diverse fields such as agriculture, medicine, and pharmacology. This review covers the stages of NMR-based metabolomics, including historical aspects and limitations, with sample preparation, data acquisition, spectral processing, analysis, and their application parts.
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Chitin-glucan complex (CGC) is an emerging novel prebiotic with numerous physiological activities in amelioration of clinical manifestations. In the present work, natural deep eutectic solvent (NADES), ultrasonication, and submerged fermentation using probiotic microorganisms were deployed for the extraction of CGC from Shiitake fruiting bodies. CGC obtained through non-ultrasonication assisted fermentation employing Lactiplantibacillus plantarum exhibited maximum polysaccharide yield (27.86 ± 0.82 % w/w). However, based on antioxidant potential, NADES combination of urea: glycerol (1:1 M ratio) was selected for further characterization. The rheological behavior of CGC under optimized conditions showed shear thinning property in both 0.1 M NaCl and salt-free solution. FTIR, 1H-(1D), and 2D 1H1H Homonuclear NMR spectra displayed distinctive patterns associated with ß-glycosidic linkage and ß-d-glucopyranose sugar moiety. XRD profiles of CGC exhibited characteristic peaks at 2θ = 23°, 25°, and 28° with corresponding hkl values of (220), (101), and (130) lattice planes, respectively. Enhanced radical scavenging activities were noticed due to the triple helical structure and anionic nature of CGC. CGC exhibited potential prebiotic activity (prebiotic score 118-134 %) and short chain fatty acids liberation (maximum 9.99 ± 0.41 mM by Lactobacillus delbrueckii). Simulated static in-vitro digestion demonstrated that CGC withstands acidic environment of gastric phase, which indicated its suitability for use as a prebiotic in nutraceutical-enriched food products.
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Quitina , Disolventes Eutécticos Profundos , Cuerpos Fructíferos de los Hongos , Glucanos , Prebióticos , Hongos Shiitake , Glucanos/química , Glucanos/aislamiento & purificación , Cuerpos Fructíferos de los Hongos/química , Quitina/química , Quitina/aislamiento & purificación , Hongos Shiitake/química , Disolventes Eutécticos Profundos/química , Antioxidantes/química , Antioxidantes/farmacología , Fermentación , Lactobacillus plantarum/metabolismoRESUMEN
The investigation of cycloaddition reactions involving acridine-based dipolarophiles revealed distinct regioselectivity patterns influenced mainly by the electronic factor. Specifically, the reactions of methyl-(2E)-3-(acridin-4-yl)-prop-2-enoate and 4-[(1E)-2-phenylethenyl]acridine with unstable benzonitrile N-oxides were studied. For methyl-(2E)-3-(acridin-4-yl)-prop-2-enoate, the formation of two regioisomers favoured the 5-(acridin-4-yl)-4,5-dihydro-1,2-oxazole-4-carboxylates, with remarkable exclusivity in the case of 4-methoxybenzonitrile oxide. Conversely, 4-[(1E)-2-phenylethenyl]acridine displayed reversed regioselectivity, favouring products 4-[3-(substituted phenyl)-5-phenyl-4,5-dihydro-1,2-oxazol-4-yl]acridine. Subsequent hydrolysis of isolated methyl 5-(acridin-4-yl)-3-phenyl-4,5-dihydro-1,2-oxazole-4-carboxylates resulted in the production of carboxylic acids, with nearly complete conversion. During NMR measurements of carboxylic acids in CDCl3, decarboxylation was observed, indicating the formation of a new prochiral carbon centre C-4, further confirmed by a noticeable colour change. Overall, this investigation provides valuable insights into regioselectivity in cycloaddition reactions and subsequent transformations, suggesting potential applications across diverse scientific domains.
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We presented a strategy utilizing 2D NMR-based metabolomic analysis of crude extracts, categorized by different pharmacological activities, to rapidly identify the primary bioactive components of TCM. It was applied to identify the potential bioactive components from Scutellaria crude extracts that exhibit anti-non-small cell lung cancer (anti-NSCLC) activity. Four Scutellaria species were chosen as the study subjects because of their close phylogenetic relationship, but their crude extracts exhibit significantly different anti-NSCLC activity. Cell proliferation assay was used to assess the anti-NSCLC activity of four species of Scutellaria. 1H-13C HSQC spectra were acquired for the chemical profiling of these crude extracts. Based on the pharmacological classification (PCA, OPLS-DA and univariate hypothesis test) were performed to identify the bioactive constituents in Scutellaria associated with the anti-NSCLC activity. As a result, three compounds, baicalein, wogonin and scutellarin were identified as bioactive compounds. The anti-NSCLC activity of the three potential active compounds were further confirmed via cell proliferation assay. The mechanism of the anti-NSCLC activity by these active constituents was further explored via flow cytometry and western blot analyses. This study demonstrated 2D NMR-based metabolomic analysis of pharmacologically classified crude extracts to be an efficient approach to the identification of active components of herbal medicine.
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Carcinoma de Pulmón de Células no Pequeñas , Proliferación Celular , Espectroscopía de Resonancia Magnética , Metabolómica , Extractos Vegetales , Scutellaria , Scutellaria/química , Humanos , Proliferación Celular/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Apigenina/farmacología , Apigenina/química , Apigenina/aislamiento & purificación , Apigenina/análisis , Flavanonas/farmacología , Flavanonas/química , Flavanonas/aislamiento & purificación , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Glucuronatos/farmacología , Glucuronatos/aislamiento & purificación , Glucuronatos/química , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Ensayos de Selección de Medicamentos AntitumoralesRESUMEN
The lignin from tritordeum straw, a hybrid cereal from crossbreeding of durum wheat and wild barley, was isolated and chemically characterized. Its composition and structure were studied by analytical pyrolysis (Py-GC/MS), nuclear magnetic resonance spectroscopy (NMR), Derivatization Followed by Reductive Cleavage (DFRC) method, and gel permeation chromatography (GPC). The data revealed an enrichment of guaiacyl (G) units (H:G:S of 3:61:36), which had a significant impact on the distribution of inter-unit linkages. The predominant linkages were the ß-O-4' alkyl-aryl ethers (78 % of all linkages), with substantial proportions of condensed linkages such as phenylcoumarans (11 %), resinols (4 %), spirodienones (4 %), and dibenzodioxocins (2 %). Moreover, DFRC revealed that tridordeum straw lignin was partly acylated at the γ-OH with both acetates and p-coumarates. Acetates were principally attached to G-units, whereas p-coumarates were predominantly attached to S-units. Furthermore, and more importantly, tritordeum lignin incorporates remarkable amounts of a valuable flavone, tricin, exceeding 30 g per kilogram of straw. Given the diverse industrial applications associated with this high-value molecule, tritordeum straw emerges as a promising and sustainable resource for its extraction.
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Grano Comestible , Flavonoides , Lignina , Lignina/química , Grano Comestible/química , Estructura Molecular , Acetatos/análisisRESUMEN
In this study, a response surface methodology (RSM) was used to determine the best combination for acid degradation parameters to reduce the viscosity of Plantago ovata Forssk seed polysaccharide (POFP). Then, the two major homogeneous polysaccharides (AH-POFP1 and AH-POFP3) were obtained by DEAE-650 M and Sephadex G-100 column chromatography. The apparent structure of the main fraction AH-POFP1 was characterized by SEM, TG and XRD, and the linkage of AH-POFP1 was determined by a combination of partial acidolysis, Smith's degradation, methylation analysis and 2D NMR analysis. Structural analysis showed that AH-POFP1 was mainly composed of xylose, with a molecular weight of 618.1 kDa, and had a backbone of 1 â 4-linked Xylp, as well as branches of T-linked Xylp, 1 â 4-linked Xylp attached to the O-2 position. The antioxidant activity assays showed that the both AH-POFP1 and AH-POFP3 possess strong scavenging radical ability. Moreover, AH-POFP1 inhibits the secretion of pro-inflammatory factors, and promotes the secretion of anti-inflammatory factors, thereby exerting anti-inflammatory effects. These findings may help to guide future applications of Plantago ovata Forssk in the fields of food, health care, and pharmacy.
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Plantago , Plantago/química , Polisacáridos/química , Antioxidantes/farmacología , Antioxidantes/análisis , Semillas/química , Antiinflamatorios/farmacologíaRESUMEN
Two new triterpenoids, namely 24-methylene-5,24-dien-19(10â9)-abeo-8α,9ß,10α-eupha-3ß-ol (1) and 24-methyl-5,23-dien-19(10â9)-abeo-8α,9ß,10α-eupha-3ß-ol (2) were isolated from the stems of Euphorbia royleana, together with three known analogs. The structures of the new compounds were elucidated by extensive 1H NMR,13C NMR, HSQC, HMBC, 1H-1H COSY, ROESY and HR-MS spectroscopic analyses.
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Lignin is a very attractive and abundant biopolymer with the potential to be a biorenewable source of a large number of value-added organic chemicals. The current state-of-the-art methods fail to provide efficient valorization of lignin in this regard without the involvement of harsh conditions and auxiliary substances that compromise the overall sustainability of the proposed processes. Making an original approach from the set of mildest temperature and pressure conditions, this work identifies and explores the capacity of an aqueous solution of the nonvolatile ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) to partially depolymerize technical lignin (Indulin AT) by means of a treatment consisting in the simple contact at ambient temperature and pressure. Among a considerable number of valuable phenolic molecules that were identified in the resulting fluid, vanillin (yield of about 3 g/kg) and guaiacol (yield of about 1 g/kg) were the monophenolic compounds obtained in a higher concentration. The properties of the post-treatment solids recovered remain similar to those of the original lignin, although with a relatively lower abundance of guaiacyl units (in agreement with the generation of guaiacyl-derived phenolic molecules, such as vanillin and guaiacol). The assistance of the treatment with UV irradiation in the presence of nanoparticle catalysts does not lead to an improvement in the yields of phenolic compounds.
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Benzaldehídos , Imidazoles , Líquidos Iónicos , Líquidos Iónicos/química , Lignina/química , Temperatura , Biomasa , Agua , Acetatos , Fenoles , GuayacolRESUMEN
The reaction of butyryl chloride with ethynylbenzene in the presence of AlCl3 afforded a mixture of the Z/E-isomers of 1-chloro-2-phenylhex-1-en-3-one. 1,2-Diphenylethyne under these conditions gave a novel polycarbocycle core, 6aH-benzo[a]fluorene. The chemical structure of 11-chloro-5,6-diphenyl-6a-propyl-6aH-benzo[a]fluorene was established by means of IE-MS, 1 H, 13 C NMR, COSY, HSQC, HMBC, and 2D INADEQUATE technique.
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INTRODUCTION: The genus Clusia L. is mostly recognised for the production of prenylated benzophenones and tocotrienol derivatives. OBJECTIVES: The objective of this study was to map metabolome variation within Clusia minor organs at different developmental stages. MATERIAL AND METHODS: In total 15 organs/stages (leaf, flower, fruit, and seed) were analysed by UPLC-MS and 1H- and heteronuclear multiple-bond correlation (HMBC)-NMR-based metabolomics. RESULTS: This work led to the assignment of 46 metabolites, belonging to organic acids(1), sugars(2) phenolic acids(1), flavonoids(3) prenylated xanthones(1) benzophenones(4) and tocotrienols(2). Multivariate data analyses explained the variability and classification of samples, highlighting chemical markers that discriminate each organ/stage. Leaves were found to be rich in 5-hydroxy-8-methyltocotrienol (8.5 µg/mg f.w.), while flowers were abundant in the polyprenylated benzophenone nemorosone with maximum level detected in the fully mature flower bud (43 µg/mg f.w.). Nemorosone and 5-hydroxy tocotrienoloic acid were isolated from FL6 for full structural characterisation. This is the first report of the NMR assignments of 5-hydroxy tocotrienoloic acid, and its maximum level was detected in the mature fruit at 50 µg/mg f.w. Seeds as typical storage organ were rich in sugars and omega-6 fatty acids. CONCLUSION: To the best of our knowledge, this is the first report on a comparative 1D-/2D-NMR approach to assess compositional differences in ontogeny studies compared with LC-MS exemplified by Clusia organs. Results derived from this study provide better understanding of the stages at which maximal production of natural compounds occur and elucidate in which developmental stages the enzymes responsible for the production of such metabolites are preferentially expressed.
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Clusia , Clusia/química , Frutas/química , Cromatografía Liquida , Espectrometría de Masas en Tándem , Benzofenonas/análisis , Benzofenonas/química , Benzofenonas/metabolismo , Flores/química , Hojas de la Planta/química , Metabolómica/métodos , Semillas/química , Azúcares/análisisRESUMEN
Type I lipoteichoic acid (LTA) is a glycerol phosphate polymer found in the cell envelope of diverse Gram-positive bacteria. The glycerol phosphate backbone is often further decorated with D-alanine and/or sugar residues. Here, we provide details of a 1-butanol extraction and purification method of type I LTA by hydrophobic interaction chromatography. The protocol has been adapted from methods originally described by Fischer et al. (Eur J Biochem 133:523-530, 1983) and further optimized by Morath et al. (J Exp Med 193:393-397, 2001). We also present information on a 2D nuclear magnetic resonance (NMR) analysis method to gain chemical and structural information of the purified LTA material.
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Glicerol , Lipopolisacáridos , Lipopolisacáridos/metabolismo , Ácidos Teicoicos/química , Cromatografía , Espectroscopía de Resonancia Magnética , Interacciones Hidrofóbicas e Hidrofílicas , FosfatosRESUMEN
Plant vascular pathogens use different ways to reach the xylem vessels and cause devastating diseases in plants. Resistant and tolerant plants have evolved various defense mechanisms against vascular pathogens. Inducible physico-chemical structures, such as the formation of tyloses and wall reinforcements with phenolic polymers, are very effective barriers that confine the pathogen and prevent colonization. Here, we use a combination of classical histochemistry along with bright-field and fluorescence microscopy and two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy to visualize and characterize wall reinforcements containing phenolic wall polymers, namely, lignin, ferulates, and suberin, which occur in different xylem vasculature in response to pathogen attack.