Untargeted Metabolomics Reveals the Potential Antidepressant Activity of a Novel Adenosine Receptor Antagonist

Depression is the most common mental illness, affecting approximately 4.4% of the global population. Despite many available treatments, some patients exhibit treatment-resistant depression. Thus, the need to develop new and alternative treatments cannot be overstated. Adenosine receptor antagonists have emerged as a promising new class of antidepressants. The current study investigates a novel dual A₁/A_2A adenosine receptor antagonist, namely 2-(3,4-dihydroxybenzylidene)-4-methoxy-2,3-dihydro-1H-inden-1-one (1a), for antidepressant capabilities by determining its metabolic profiles and comparing them to those of two reference compounds (imipramine and KW-6002). The metabolic profiles were obtained by treating male Sprague-Dawley rats with 1a and the reference compounds and subjecting them to the forced swim test. Serum and brain material was consequently collected from the animals following euthanasia, after which the metabolites were extracted and analyzed through untargeted metabolomics using both ¹H-NMR and GC-TOFMS. The current study provides insight into compound 1a’s metabolic profile. The metabolic profile of 1a was similar to those of the reference compounds. They potentially exhibit their antidepressive capabilities via downstream effects on amino acid and lipid metabolism.     

Development of a Wine Metabolomics Approach for the Authenticity Assessment of Selected Greek Red Wines

Wine metabolomics constitutes a powerful discipline towards wine authenticity assessment through the simultaneous exploration of multiple classes of compounds in the wine matrix. Over the last decades, wines from autochthonous Greek grape varieties have become increasingly popular among wine connoisseurs, attracting great interest for their authentication and chemical characterization. In this work, 46 red wine samples from Agiorgitiko and Xinomavro grape varieties were collected from wineries in two important winemaking regions of Greece during two consecutive vintages and analyzed using ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QToF-MS). A targeted metabolomics methodology was developed, including the determination and quantification of 28 phenolic compounds from different classes (hydroxycinnamic acids, hydroxybenzoic acids, stilbenes and flavonoids). Moreover, 86 compounds were detected and tentatively identified via a robust suspect screening workflow using an in-house database of 420 wine related compounds. Supervised chemometric techniques were employed to build an accurate and robust model to discriminate between two varieties.     

Metabolite Fingerprinting Using 1H-NMR Spectroscopy and Chemometrics for Classification of Three Curcuma Species from Different Origins

Curcuma longa, Curcuma xanthorrhiza, and Curcuma manga have been widely used for herbal or traditional medicine purposes. It was reported that turmeric plants provided several biological activities such as antioxidant, anti-inflammatory, hepatoprotector, cardioprotector, and anticancer activities. Authentication of the Curcuma species is important to ensure its authenticity and to avoid adulteration practices. Plants from different origins will have different metabolite compositions because metabolites are affected by soil nutrition, climate, temperature, and humidity. ¹H-NMR spectroscopy, principal component analysis (PCA), and orthogonal projections to latent structures-discriminant analysis (OPLS-DA) were used for authentication of C. longa, C. xanthorrhiza, and C. manga from seven different origins in Indonesia. From the ¹H-NMR analysis it was obtained that 14 metabolites were responsible for generating classification model such as curcumin, demethoxycurcumin, alanine, methionine, threonine, lysine, alpha-glucose, beta-glucose, sucrose, alpha-fructose, beta-fructose, fumaric acid, tyrosine, and formate. Both PCA and OPLS-DA model demonstrated goodness of fit (R² value more than 0.8) and good predictivity (Q² value more than 0.45). All OPLS-DA models were validated by assessing the permutation test results with high value of original R² and Q². It can be concluded that metabolite fingerprinting using ¹H-NMR spectroscopy and chemometrics provide a powerful tool for authentication of herbal and medicinal plants.     

Recombinant Thaumatin-Like Protein (rTLP) and Chitinase (rCHI) from Vitis vinifera as Models for Wine Haze Formation

Cross-linking net aggregates of thermolabile thaumatin-like proteins (TLPs) and chitinases (CHIs) are the primary source of haze in white wines. Although bentonite fining is still routinely used in winemaking, alternative methods to selectively remove haze proteins without affecting wine organoleptic properties are needed. The availability of pure TLPs and CHIs would facilitate the research for the identification of such technological advances. Therefore, we proposed the usage of recombinant TLP (rTLP) and CHI (rCHI), expressed by Komagataella phaffii, as haze-protein models, since they showed similar characteristics (aggregation potential, melting point, functionality, glycosylation levels and bentonite adsorption) to the native-haze proteins from Vitis vinifera. Hence, rTLP and rCHI can be applied to study haze formation mechanisms on a molecular level and to explore alternative fining methods by screening proteolytic enzymes and ideal adsorptive resins.     

Optimization of Sample Preparation for Metabolomics Exploration of Urine,Feces, Blood and Saliva in Humans Using Combined NMR and UHPLC-HRMS Platforms

Currently, most clinical studies in metabolomics only consider a single type of sample such as urine, plasma, or feces and use a single analytical platform, either NMR or MS. Although some studies have already investigated metabolomics data from multiple fluids, the information is limited to a unique analytical platform. On the other hand, clinical studies investigating the human metabolome that combine multi-analytical platforms have focused on a single biofluid. Combining data from multiple sample types for one patient using a multimodal analytical approach (NMR and MS) should extend the metabolome coverage. Pre-analytical and analytical phases are time consuming. These steps need to be improved in order to move into clinical studies that deal with a large number of patient samples. Our study describes a standard operating procedure for biological specimens (urine, blood, saliva, and feces) using multiple platforms (¹H-NMR, RP-UHPLC-MS, and HILIC-UHPLC-MS). Each sample type follows a unique sample preparation procedure for analysis on a multi-platform basis. Our method was evaluated for its robustness and was able to generate a representative metabolic map.     

Environmental metabolomics: new insights into earthworm ecotoxicity and contaminant bioavailability in soil

Environmental metabolomics is a growing and emerging sub-discipline of metabolomics. Studies with earthworms have progressed from the initial stages of simple contact exposure tests to detailed studies of earthworm responses in soil. Over the past decade, a variety of endogenous metabolites have been identified as potential biomarkers of contaminant exposure. Furthermore, metabolomic methods have delineated responses from sub-lethal exposure of earthworms to polycyclic aromatic hydrocarbons and metals in soil suggesting that environmental metabolomics may be used as a direct measure of contaminant bioavailability in soil. Environmental metabolomics has the potential to fill knowledge gaps related to earthworm toxicity and contaminant bioavailability. However, challenges with metabolite quantification and limited systems-level models of metabolic data require improvement before detailed models of “normal” responses can be developed and used routinely in assessment of contaminated sites. Nonetheless, environmental metabolomics is poised to improve our fundamental understanding of earthworm responses and toxicity to contaminants in soil. Figure Principal component analysis (PCA) scores plots of earthworm metabolic profiles measured by ¹H NMR spectroscopy after exposure to sub-lethal concentrations of phenanthrene in soil.

Zur Struktur der Produkte der Reaktion vonE/Z-1-Benzolsulfonyl-3-(1-pentenyl)-indol mit N-Phenylmaleinimid: Ein erster Beitrag zur Konfigurations- und Konformationsanalyse in der Vinylindol-Cycloadditionsreihe

The products2,3 of the reaction ofE/Z-1-benzenesulfonyl-3-(1-pentenyl)-indole (1) and N-phenylmaleimide were analysed by¹H-NMR spectroscopy. Exemplarily, the structure elucidation of theendo-cyclo-adduct2 b was achieved by using several NMR techniques (diff. NOE-, INDOR-measurements, decoupling experiments, spectra simulation). The¹H-NMR-spectroscopically gained prediction of relative configuration and conformation of2 b was supported on X-ray analysis. The cyclohexene ring of the new cycloadducts adopts in the liquid phase and in the crystal a slightly twisted boat conformation.

     

Evaluation of Plant-Based Byproducts as Green Fining Agents for Precision Winemaking

Consumers are increasingly looking for foods, including wine, that are free of animal-derived proteins. This study seeks to evaluate patatin, a new, plant-based and allergen-free fining agent, by comparing it with the fining agents polyvinipolypyrrolidone, bovine serum albumin, and methylcellulose. Specifically, its effects on the phenolic profile of enological tannins were analyzed with four spectrophotometric assays: OD 280 nm, Folin–Ciocâlteu, Adams–Harbertson, and methylcellulose. In addition, changes in the polyphenol composition of Sangiovese red wine were determined by UV-Vis spectrophotometry and HPLC with adsorption trials, and the solid–liquid interaction in a wine solution was modeled by both Langmuir and Freundlich equations. Our findings highlight the occurrence of systematic proportional error between the selected spectrophotometric assays. As a result, direct comparisons of protein precipitation assays can be made only among results obtained with the same spectrophotometric method. However, it is clear that patatin has an impact on the phenolic profile of Sangiovese red wine: it removes simple phenolics (gallic acid, (+)-catechin, (–)-epicatechin, epicatechin gallate, syringic acid, fertaric acid, coutaric acid, and rutin) as well as both oligomeric and polymeric tannins to different extents. In concentrations of less than 1 g/L, the patatin isotherm showed a linear relation between the equilibrium concentration and the quantity absorbed, obeying the Freundlich model reasonably well (K_F 1.46; 1/n 1.07; R² 0.996 with 1/n > 1). Thus, the adsorption process is strongly dependent on the fining dosage.     

Determination of the geographical origin of Brazilian wines by isotope and mineral analysis

In the present research, we studied wines from three different south Brazilian winemaking regions with the purpose of differentiating them by geographical origin of the grapes. Brazil's wide territory and climate diversity allow grape cultivation and winemaking in many regions of different and unique characteristics. The wine grape cultivation for winemaking concentrates in the South Region, mainly in the Serra Gaúcha, the mountain area of the state of Rio Grande do Sul, which is responsible for 90% of the domestic wine production. However, in recent years, two new production regions have developed: the Campanha, the plains to the south and the Serra do Sudeste, the hills to the southeast of the state. Analysis of isotopic ratios of ¹⁸O/¹⁶O of wine water, ¹³C/¹²C of ethanol, and of minerals were used to characterize wines from different regions. The isotope analysis of δ¹⁸O of wine water and minerals Mg and Rb were the most efficient to differentiate the regions. By using isotope and mineral analysis, and discrimination analysis, it was possible to classify the wines from south Brazil.     

The Impact of Grape Varieties to Wine Isotopic Characterization

This paper highlights the results of a study regarding the impact of geo-climatic conditions, the influence of grape varieties, and harvest year on the isotopic characterization of a wine from a specific vineyard area, using stable isotope ratio analysis by continuous flow mass spectrometry CF-IRMS. This analytical technique has made a significant contribution on wine characterization, by proving the botanical and geographical origin of the wine raw material.

A great variability was observed to sap ¹⁸O and ²H isotopic ratios for different types of vine (Vitis vinifera plant) from the studied area, Dealu Mare-Valea Calugareasca, reflecting the significant influence of variety on isotopic features. On the other hand, the comparison of stable isotopic fingerprints for rainfall water and sap revealed a close approximation value for ¹⁸O isotopic ratio, and an insignificant variation coefficient of ¹³C isotopic ratio in wine varieties (about 2.85%).

The results of isotopic characterization for grape vine sap and original wines for different varieties existing in Dealu Mare-Valea Calugareasca vineyard indicates the relevance of meteorological and viticulture parameters like precipitation, date of vintage, and grape cultivar for wine authentication process.     

1H-NMR Profiling Shows as Specific Constituents Strongly Affect the International EVOO Blends Characteristics: The Case of the Italian Oil

Considering the growing number of extra virgin olive oil (EVOO) producers in the world, knowing the influence of olive oils with different geographical origins on the characteristics of the final blend becomes an interesting goal. The present work is focused on commercial organic EVOO blends obtained by mixing multiple oils from different geographical origins. These blends have been studied by ¹H-NMR spectroscopy supported by multivariate statistical analysis. Specific characteristics of commercial organic EVOO blends originated by mixing oils from Italy, Tunisia, Portugal, Spain, and Greece were found to be associated with the increasing content of the Italian component. A linear progression of the metabolic profile defined characteristics for the analysed samples—up to a plateau level—was found in relation to the content of the main constituent of the Italian oil, the monocultivar Coratina. The Italian constituent percentage appears to be correlated with the fatty acids (oleic) and the polyphenols (tyrosol, hydroxytyrosol, and derivatives) content as major and minor components respectively. These results, which highlight important economic aspects, also show the utility of ¹H-NMR associated with chemometric analysis as a powerful tool in this field. Mixing oils of different national origins, to obtain blends with specific characteristics, could be profitably controlled by this methodology.     

Widely-Targeted Metabolic Profiling in Lycium barbarum Fruits under Salt-Alkaline Stress Uncovers Mechanism of Salinity Tolerance

Wolfberry (Lycium barbarum L.) is an important economic crop widely grown in China. The effects of salt-alkaline stress on metabolites accumulation in the salt-tolerant Ningqi1 wolfberry fruits were evaluated across 12 salt-alkaline stress gradients. The soil pH, Na⁺, K⁺, Ca²⁺, Mg^2+, and HCO₃⁻ contents decreased at a gradient across the salt-alkaline stress gradients. Based on the widely-targeted metabolomics approach, we identified 457 diverse metabolites, 53% of which were affected by salt-alkaline stress. Remarkably, soil salt-alkaline stress enhanced metabolites accumulation in wolfberry fruits. Amino acids, alkaloids, organic acids, and polyphenols contents increased proportionally across the salt-alkaline stress gradients. In contrast, nucleic acids, lipids, hydroxycinnamoyl derivatives, organic acids and derivatives and vitamins were significantly reduced by high salt-alkaline stress. A total of 13 salt-responsive metabolites represent potential biomarkers for salt-alkaline stress tolerance in wolfberry. Specifically, we found that constant reductions of lipids and chlorogenic acids; up-regulation of abscisic acid and accumulation of polyamines are essential mechanisms for salt-alkaline stress tolerance in Ningqi1. Overall, we provide for the first time some extensive metabolic insights into salt-alkaline stress tolerance and key metabolite biomarkers which may be useful for improving wolfberry tolerance to salt-alkaline stress.     

The Synthesis of Novel Crown Ethers, Part VII [1]. Coumarin Derivatives of Benzocrowns and Cation Binding from Fluorescence Spectra

4-[3-(1-benzopyran-2-one)] derivativesof benzo[12]crown-4, benzo[15]crown-5 andbenzo-[18]crown-6 were synthesized from4-[3-(1-benzopyran-2-one)]-1,2-dihydroxy-benzenereacting with bis-ethyleneglycol dihalides orpentaethylene glycol ditosylate in alkali carbonate/DMF/water. The original products were identified byhigh resolution EI-mass spectra as well as IR,¹H-NMR and ¹³C-NMR spectroscopy. The 1 : 1binding constants of Mg²⁺, Li⁺, Na⁺ andK⁺ with the coumarin-benzocrowns were estimated usingfluorescence emission spectroscopy in acetonitrile.The complexing enhanced quenching fluorescence spectra(CEQFS) and complexing enhanced fluorescence spectra(CEFS) exhibited the ion binding powers due tocationic recognition rules of the macrocycles.     

Keto-enol and enol-enol tautomerism in trifluoromethyl-β-diketones

The keto-enol (K?E) and enol-enol (E?E) equilibria of a variety of trifluoromethyl-β-diketones were investigated using ¹H, ¹³C, ¹⁹F NMR spectroscopy, infrared spectroscopy and ultraviolet-visible spectrophotometry in nonpolar solvents. In general, NMR, IR and UV spectral evidence indicates that trifluoromethyl-β-diketones exist as mixtures of two chelated cis-enol forms in nonpolar media. Infrared spectroscopy and ultraviolet spectrophotometry show the E?E equilibrium lies in the direction of the enol form which maximizes conjugation in most cases. Exceptions are noted and discussed.     

The Synthesis and the Cationic Fluorescence Role of Glycols with Aromatic End Groups, Part III

Some novel bis-(substituted-phenoxy) ended glycols were synthesised usinghydroxy aromatics of vanillin, o-vanillin, iso-vanillin and 4-hydroxy coumarin which reacted with bis-dihalides of polyglycols in the presence ofDMSO/alkali carbonate. The novel podands, Ar-(CH₂CH₂O)_m-Ar,(m = 1–4), were identified with IR, ¹H-NMR, ¹³C-NMR and mass spectrometry. The various (formyl-methoxy)phenyl and 4-oxycoumarin derivatives of glycols were studied to estimate the cation binding selectivity of SCN^- salts ofLi⁺, Na⁺, K⁺ and Zn²⁺ cations in acetonitrile using steady statefluorescence spectroscopy. The relevant structures of podands have shown goodselectivity depending on the cation and the glycollength, although the chromophoreend groups have no specific contribution on binding.     

Discrimination between genetically identical peony roots from different regions of origin based on 1H-nuclear magnetic resonance spectroscopy-based metabolomics: determination of the geographical origins and estimation of the mixing proportions of blended samples

Sixty peony root training samples of the same age were collected from various regions in Korea and China, and their genetic diversity was investigated for 23 chloroplast intergenic space regions. All samples were genetically indistinguishable, indicating that the DNA-based techniques employed were not appropriate for determining the samples’ regions of origin. In contrast, ¹H-nuclear magnetic resonance (¹H-NMR) spectroscopy-based metabolomics coupled with multivariate statistical analysis revealed a clear difference between the metabolic profiles of the Korean and Chinese samples. Orthogonal projections on the latent structure-discrimination analysis allowed the identification of potential metabolite markers, including γ-aminobutyric acid, arginine, alanine, paeoniflorin, and albiflorin, that could be useful for classifying the samples’ regions of origin. The validity of the discrimination model was tested using the response permutation test and blind prediction test for internal and external validations, respectively. Metabolomic data of 21 blended samples consisting of Korean and Chinese samples mixed at various proportions were also acquired by ¹H-NMR analysis. After data preprocessing which was designed to eliminate uncontrolled deviations in the spectral data between the testing and training sets, a new statistical procedure for estimating the mixing proportions of blended samples was established using the constrained least squares method for the first time. The predictive procedure exhibited relatively good predictability (adjusted R ²?=?0.7669), and thus has the potential to be used in the quality control of peony root by providing correct indications for a sample’s geographical origins.

SCHWEFELDIIMIDE MIT SILYL-, GERMYL-, STANNYL- UND PHOSPHINYL-HETEROSUBSTITUENTEN. SYNTHESE UND NMR-SPEKTROSKOPISCHE CHARAKTERISIERUNG

Abstract

Reactions of the salts K₂SN₂ and K[(NSN)R] (R = ′Bu, SiMe₃ and P′Bu₂) with organoelement chlorides R′R′ěl have been used to prepare four series of model sulfur diimides: R′R″E(NSN)ER″R′, ′Bu(NSN)ER″R′, Me₃Si(NSN)E″R′ and ^tBu₂P(NSN)ER″R′, respectively (E = C, Si, Ge, Sn; R′ and R″ = alkyl or aryl group). All compounds have been characterized by ′H and ¹³C NMR and—if possible—by ³¹P, ²⁹Si and ¹¹⁹Sn NMR spectroscopy. The configuration (Z or E) of the substituents R and E″R′ has been assigned in several cases using ^tBu(NSN)^tBu (1) as a reference. The E,Z assignment of ¹H, ¹³C and ¹⁵N nuclei in 1 is based on selectively ¹H-decoupled refocused INEPT ¹⁵N NMR and two-dimensional (2D) ¹³C/¹H heteronuclear shift correlations. The sulfur diimides under study are in general fluxional in solution.     

Untargeted metabolomic analysis using liquid chromatography quadrupole time-of-flight mass spectrometry for non-volatile profiling of wines

The current study presents a method for comprehensive untargeted metabolomic fingerprinting of the non-volatile profile of the Graciano Vitis vinifera wine variety, using liquid chromatography/electrospray ionization time of flight mass spectrometry (LC–ESI-QTOF). Pre-treatment of samples, chromatographic columns, mobile phases, elution gradients and ionization sources, were evaluated for the extraction of the maximum number of metabolites in red wine. Putative compounds were extracted from the raw data using the extraction algorithm, molecular feature extractor (MFE). For the metabolite identification the WinMet database was designed based on electronic databases and literature research and includes only the putative metabolites reported to be present in oenological matrices. The results from WinMet were compared with those in the METLIN database to evaluate how much the databases overlap for performing identifications. The reproducibility of the analysis was assessed using manual processing following replicate injections of Vitis vinifera cv. Graciano wine spiked with external standards. In the present work, 411 different metabolites in Graciano Vitis vinifera red wine were identified, including primary wine metabolites such as sugars (4%), amino acids (23%), biogenic amines (4%), fatty acids (2%), and organic acids (32%) and secondary metabolites such as phenols (27%) and esters (8%). Significant differences between varieties Tempranillo and Graciano were related to the presence of fifteen specific compounds.     

Complexes of aluminium(III) with picolinic and pipecolinic acids: An27Al-NMR investigation

Summary Aluminium-27 NMR has been employed for the study of the interaction of Al(III) with picolinic (pic-H) and pipecolinic (pip-H) acids in aqueous solution at variablepH. In the reaction with picolinic acid distinct peaks for hydrated Al(III), 1:1 and 1:2 Al-picolinate complexes, as well as a mixed hydroxo-picolinato complex Al(pic)₂OH are observed. An insoluble 1:3 picolinate complex is formed atpH 3. Pipecolinic acid forms 1:1 and 1:2 Al-pipecolinate complexes. No hydroxy-pipecolinate species are formed, however, and the 1:2 complex is deprotonated abovepH 4.5 to colin- (pic-H) und Pipecolinsäure (pip-H) in wäßriger Lösung bei verschiedenenpH angewandt. Bei Al(pip)(H_–1 pip) have been isolated and characterized by elemental analysis, IR and¹H-NMR.

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Komplexe von Aluminium(III) mit Picolin- und Pipecolinsäure: Eine²⁷Al-NMR-Untersuchung

Zusammenfassung ²⁷Al-NMR wurde zur Untersuchung von Wechselwirkungen von Al(III) mit Picolin-(pic-H) und Pipecolinsäure (pip-H) in wäßriger Lösung bei verschiedenenpH angewandt. Bei der Reaktion mit Picolinsäure wurden separate Signale für hydratisiertes Al(III), 1:1 und 1:2 Al-Picolinat-Komplexe und auch für gemischte Hydroxo-picolinat-Komplexe Al(pic)₂OH beobachtet. BeipH3 wird unlöslicher Picolinat-Komplex gebildet. Pipecolinsäure geht 1:1 und 1:2 Al-Pipecolinat-Komplexe ein. Es werden keine Hydroxo-Pipecolinat-Komplexe gebildet. Der 1:2 Komplex wird über einempH von 4.5 deprotoniert und ergibt den unlöslichen Komplex Al(pip)(H_–1 pip). Die [3, 4] as well as those undergoing dialysis treatment for chronic renal failure [5]. taranalyse, IR und¹H-NMR charakterisiert.

     

Electrostatic Effects on the Inclusion Process of Sodium p-(3-t-Butyl-4-Hydroxyphenylazo)Benzene Sulfonate with Modified Cyclodextrin and Its Metal Complex

Abstract

The electrostatic interaction between charged β-cyclodextrin having ethylenediamine group and the title azo compound was investigated by ¹H-NMR spectroscopy.