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The study provides new function tested on labetalol in large infusion volumes (Vinf = 80-115 µL) via electrospray ionization mass spectrometry, tandem MS2–MS7 operation modes and collision energy: 0, 0.1, 10, 20, 25, 26, 30 and 35 eV, respectively. It is derived from the stochastic dynamic mass spectrometric equation D”SD = 2.6388.10-17.(2>-2), which exactly quantifies analyte concentration in solution. Also, it determines 3D conformations and electronic structures. The description of mass spectrometric intensity data as random variables and the shown relation, there are written two new linear functions among D”SD parameters, average total intensity values of fragmentation peaks, infusion volume, and collision energy. They introduce covariance of datasets of variables per short span of scan time of ions in any experimental conditions “l” and “m”. They are: D”SD;m,l = D”SD,l + D”SD,m + 5.2776.10-17.{l.Im>–l>.m>}≈l>+m> and l>+m>≈|rl,m|.sd(yEr±)1.sd(yEr±)m. Those relations yields to new formula D”SD,l+ D”SD,m = |rl,m|.sd(yEr±)l.sd(yEr±)m, providing exact function of mass spectrometric variable intensity of any peaks of analyte ion in any two sets of experimental conditions of measurements and diffusion parameters according to the first formula. Correlation between theory and experiment of fragmentation processes of labetalol shows |r|=1–0.99999. Chemometrics is used.

Complete theoretical and experimental data on the entitled contribution.

A new flavone, named hildeflavone (1) along with 7 other known flavonoids were isolated from the aerial parts of Tephrosia hildebrandtii Vatke. Their characterisation was based on NMR and MS data analysis. The anti-inflammatory properties of the crude extract, isolated compounds and combination of the compounds were investigated in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). Treatment of the LPS-stimulated PBMCs with the isolated flavonoids at a concentration of 100 µM significantly reduced the production of interleukins (IL-1β, IL-2 and IL-6), interferon-gamma (IFN-γ), granulocyte macrophage-colony stimulating factor (GM-CSF) and tumour necrosis factor-alpha (TNF-α). It was also found that the combination of a flavone and flavanones exhibited remarkable synergistic anti-inflammatory effects on the production of the cytokines.

The study reports quantification of metronidazole (MTZ) in clinical human urine employing our innovative stochastic dynamic equation D”SD =2.6388.10-17.(2>–2>). There are direct analysis without presence of internal standard, using ultra-high accuracy nano-electrospray ionization (ESI) mass spectrometry (MS), quantum chemistry and chemometrics, respectively. The linear calibration D”SD =f(conc.) equations are obtained for concentration range 2.5 to 25000 ng.(mL)-1 of spiked urine samples, examining analyte MS ions at m/z 171.0998, 172.0718, 172.04081, 213.1463, 181.0722 and 151.1114, respectively. There is achieved exact coefficient of linear correlation (|r|=1) between theory and experiment of ion at m/z 172.04081. The major challenge to quantify MTZ in urine sample is that it stabilizes cations [M+H]+ of two tautomers, which equilibrium varies drastically within the standard linear calibration dynamic range. The fragmentation patterns depend on analyte tautomers and it unambiguous assignment in multicomponent samples with complex sample matrix effect (SME) is unable to be made without mediation to an independent physico-chemical law. To solve the problem, herein, is used, again, above equation, which is designed a bridge between quantitative and multidimensional structural analytical chemistry, when is used complementary with Arrhenius’s quantum chemical diffusion parameter (DQC.) There is achieved |r|=0.98 of D”SD=f(DQC’) examining tautomeric molecular and fragment ions of MTZ.

Even though maytansine was first discovered from Celastraceae plants, it was later proven to be an endophytic bacterial metabolite. However, a pure bacterial culture cannot synthesize maytansine. Therefore, an exclusive interaction between plant and endophytes is required for maytansine production. Unfortunately, our understanding of plant-endophyte interaction is minimal, and critical questions remain. For example: how do endophytes synthesize maytansine inside their plant host, and what is the impact of maytansine production in plant secondary metabolites? Our study aimed to address these questions. We selected

The kernel idea for this paper came from our more recent development of a mass spectrometric model equation, based on stochastic dynamics. It treats quantitatively the experimental intensity of analytes and their fragment ions under soft ionization conditions. The effort has resulted to exact universally applicable and empirically testable relationship, between mass spectrometric stochastic dynamic diffusion and the intensity. A linear correlation at high level of statistical significance occurs between DSD and the corresponding quantum chemical diffusions, obtained within the Arrhenius' approximation. It provides bridge between experimental MS parameters and 3D structure of analyte ions. Furthermore, we have claimed that the total intensity of the ions is proportional to their DSD parameter according to our model equation; or Itot ~ DSD. As evident from the small–scale of our contributions, so far, the simplistic theoretical concept and corresponding model equation need to be translated into a broad practical employment, because of; there is extended the capability of mass spectrometry beyond its routine application as irreplaceable method for quantitative analysis to the analytical practice. The superior features of the mass spectrometric instrumentation can offer us a new perspective of looking at the implementation of the method to exact 3D structural analysis in condense phase. As far as any such statement should be strongly quantified from the point of view of the chemometrics, this work deals with application of our stochastic dynamic concept of mass spectrometric diffusion to structural analysis of complex ions of CuII–ion with glycylhomopentapeptide and its dimeric associates. The large difference in the coordination fashion of oligopeptides, and competitive fragment paths together with the variety of the coordination modes of CuII–ion; and accounting, in parallel, for the different oxidation states of copper allows for us to demonstrate the great capability of our theoretical concept, studying so challenging research area. The experimental design is based on high resolution electrospray ionization mass spectrometric data in positive operation mode. High accuracy ab initio and methods based on theory on functional of density are used. Both static and molecular dynamic methods are employed.

Knowledge about translocation of plant protection products (PPP's) in plants is important to understand the uptake via the root system. Here we report the combination of analysis of tissue extracts by LC-HRMSn, autoradiography of 14C-labeled compounds and MALDI-MSI, which combine qualitative and quantitative information of chemical composition and the spatial distribution of PPP's and their metabolites in situ. Therefore, the uptake of the phenylamide fungicide metalaxyl was studied in tomato plants (Solanum lycopersicum) using a hydroponic system. The plants have been cultivated in perlite until the two-leaf stage and were transferred into the hydroponic test system afterwards. The radioactive labeled fungicide was readily taken up by the roots during the normal water consumption and radioactivity was translocated uniformly to the aboveground part of the tomato plants, while only small proportion of the applied radioactivity were observed in the roots. The distribution of metalaxyl after the plant uptake experiment in the primary roots where analyzed by a transversal tissue section in the zone of maturation. Metalaxyl is mainly localized in root xylem and in cortex located at the epidermis. With LC-HRMSn and radiochemical analyses of stem and leaf, no parent compound was detectable. Four polar metabolites were the main identified components of the residue and could be visualized by MALDI-imaging mass spectrometry. With these results we could show, that the fungicide metalaxyl is taken up by the plant via the roots during the regular water consumption and transported to xylem.

In the current paper, we further search for certainty of our innovative stochastic dynamic (SD) simplistic model formula D”SD = 2.6388.10-17. (2>-2) connecting among the so-called mass spectrometric SD diffusion parameter DSD parameter, the mass spectrometric measurable variable intensity, and the analyte concentration in solution. Since this equation has been derived more recently from our basic, but a more complex, formula for a large number of practical purposes of the analytical chemistry such a simplistic relationship is sufûcient significantly. Therefore, the motivation behind this work is further experimental justiûcation of the validity of this formula that is required in order to successfully apply the new model to the analytical practice. The quantification is carried out by studying reserpine (1) in solution at an analyte concentration of ng.(mL)-1. The capability of the model equation to express quantitatively the analyte concentration in solution is tested with independent chromatographic analysis. Correlation between chromatographic and mass spectrometric (MS) data is carried out by means of chemometrics. The diffusion parameters according to our stochastic dynamic concept and the simplistic model formula presented above and the corresponding diffusion data according to the current monitoring method (CMM) are correlated mutually, as well.

Background & Aims Acute liver failure (ALF) represents an unmet medical need in Western countries. Although the link between intestinal dysbiosis and chronic liver disease is well-established, there is little evidence for a functional role of gut-liver interaction during ALF. Here we hypothesized that intestinal dysbiosis may affect ALF. Methods To test this hypothesis, we assessed the association of proton pump inhibitor (PPI) or long-term antibiotics (ABx) intake, which have both been linked to intestinal dysbiosis, and occurrence of ALF in the 500,000 participants of the UK BioBank population-based cohort. For functional studies, male Nlrp6-/- mice were used as a dysbiotic mouse model and injected with a sublethal dose of acetaminophen (APAP) or lipopolysaccharide (LPS) to induce ALF. Results Multivariate Cox regression analyses revealed a significantly increased risk (odds ratio, 2.3–3) for developing ALF in UK BioBank participants with PPI or ABx. Similarly, dysbiotic Nlrp6-/- mice displayed exacerbated APAP- and LPS-induced liver injury, which was linked to significantly reduced gut and liver tissue microbiota diversity and correlated with increased intestinal permeability at baseline. Fecal microbiota transfer (FMT) from Nlrp6-/- mice into wild-type (WT) mice augmented liver injury on APAP treatment in recipient WT mice, resembling the inflammatory phenotype of Nlrp6-/- mice. Specifically, FMT skewed monocyte polarization in WT mice toward a Ly6Chi inflammatory phenotype, suggesting a critical function of these cells as sensors of gut-derived signals orchestrating the inflammatory response. Conclusions Our data show an important yet unknown function of intestinal microbiota during ALF. Intestinal dysbiosis was transferrable to healthy WT mice via FMT and aggravated liver injury. Our study highlights intestinal microbiota as a targetable risk factor for ALF., Graphical abstract

The data analyzed in this paper are on quantitative and 3D structural determination of ionic ensembles and multiply charged solvates ions of type [(Cl)(H2O)x(H3O)y(CH3CN)z]+, [(Cl)(O2)x(CH3OH)y(NH4)z]+, [(O2)x(H2O)(H3O)(CH3CN)]+n and [(Cl)(H2O)2(H3O)(CH3CHN2)]+ observable under electrospray ionization conditions in presence of ZnII-ion containing metal-organics, where x = y = z = 1–3 are the number of molecules, respectively, ions participating into each of the interacting ensemble, while “n” denotes the number of interacting ensembles forming the more complex ionic clusters. The major theoretical problem we have to deal with is the applicability of our more recently developed stochastic dynamic concept and formulas connecting among the mass spectrometric variable intensity, the so-called stochastic dynamic diffusion parameters (DSD), the temperature (T) and the analyte concentration in solution to such challenging molecular/ionic systems from the perspective of molecular structure. The DSD parameters of analyte ions correlate linearly with the so-called quantum chemical diffusion parameters (DQC) according to the Arrhenius’s theory. The work has demonstrated persuasively that these equations are capable of providing reliable analytical information about so complex ensembles of interacting species. It shows their significant advantages as analytical approaches, amongst other rival concepts, to quantify the mass spectrometric outcome intensity highly accurately, selectively, precisely and sensitively. The thermodynamics parameters of common reactions of the following ionic species observable under electrospray ionization experimental conditions of some tetrachlrozinc(II) complex ions of metal-organics are examined. These are the ions [(Cl)(H2O)(H3O)2(CH3CN)3]+ (m/z 214/216), [(Cl)(H2O)(H3O)2(CH3CN)2]+ (m/z 173/175), [(Cl)(H2O)2(H3O)2(CH3CN)]+ (m/z 150/152), [(Cl)(H2O)(H3O)2(CH3CHNH]+ (m/z 134/136,) [(Cl)(H2O)2(H3O)(CH3CHNH2]+, [(Cl)(H2O)(H3O)2(CH3CN]+ (m/z 132/134,) [(Cl)(H2O)2(H3O)2(CH3CN]+ (m/z 183/185), [(CH3OH)(H2O)5(NH4)(CH3CN)3]+3 (m/z 263,) and [(CH3OH)(H2O)(H3O)(CH3CN)]+31 (m/z 110,) respectively.

From the leaves of South African medicinal plant Melianthus comosus, four previously undescribed bufadienolides, 16β-formyloxymelianthugenin (1), 2β-acetoxymelianthusigenin (2), 2β-hydroxy-3β,5β-di-O-acetylhellebrigenin (3), and 2β-acetoxy-5β-O-acetylhellebrigenin (4) were isolated together with two known bufadienolides. The structural elucidation of the compounds was based on 1D and 2D NMR spectroscopy, high-resolution mass spectrometry, and other spectroscopic methods. The relative configurations were determined by single-crystal X-ray crystallography analysis and NOESY correlations. The isolated compounds displayed strong cytotoxicity against MCF-7 breast cancer cells, sensitive CCRF-CEM and multidrug-resistant CEM/ADR5000 leukemia cells. Compound 1 showed the most potent activity, with IC50 values of 0.07 μM towards CCRF-CEM, 0.06 μM towards CEM/ADR5000 and 0.36 μM towards MCF-7 followed by compound 4 with IC50 values of 0.13 μM towards CCRF-CEM, 0.08 μM towards CEM/ADR5000 and 0.53 μM towards MCF-7.

Matrix-assisted laser desorption/ionization imaging high-resolution mass spectrometry (MALDI-imaging-HRMS) is an important technique for visualizing the spatial distribution of compounds directly on the surface of organisms such as microorganisms, insects, plants, animals, and human tissues. However, MALDI-imaging-HRMS and the stable isotope labeling approach have never been combined for the detection and simultaneous visualization of labeled and unlabeled compounds, their analogues and derivatives, as well as their precursors. Herein, we present a methodology that labels microbial secondary metabolites directly on agar with stable isotopes and allows concurrent spatial distribution analyses by MALDI-imaging-HRMS. Using a thin film of labeled agar supplemented with [1-13C]-l-proline, [methyl-D3]-l-methionine, 15NH4Cl, or [15N]-l-serine overlaid on unlabeled agar, we demonstrate the incorporation of labeled precursors into prodiginines and serratamolides produced by an endophytic bacterium, Serratia marcescens, by MALDI-imaging-HRMS and HPLC-HRMS. Further, we show the incorporation of CD3 into prodigiosin as well as its characteristic fragments directly by MALDI-imaging-HRMS2. Our methodology has several advantages over currently existing techniques. First, both labeled and unlabeled compounds can be visualized simultaneously in high spatial resolution along with their labeled and unlabeled precursors. Second, by using a thin film of labeled agar, we utilize minimum amounts of expensive labeled compounds (1-3 mg) ensuring a cost-effective method for investigating biosynthetic pathways. Finally, our method allows in situ visualization and identification of target and nontarget compounds without the need of isolating the compounds. This is important for compounds that are produced by microorganisms in low, physiologically, or ecologically relevant concentrations.

Background The surface layers of two German grassland soils, a silt loam soil from Dortmund (Soil A) and a sandy loam soil from Hannover (Soil B), were subjected to the Humeomics fractionation to identify the molecular composition of the soil Humeome. Methods The separated Humeomic fractions were analysed by high performance size exclusion chromatography hyphenated to a high-resolution electrospray-Orbitrap Mass Spectrometry (MS). Empirical formulae were obtained by mass data to describe the carbon and nitrogen molecular structures in the soil organic matter (SOM) of both soils. Results Results showed 175 masses for Soil A and 139 for Soil B distributed among the Humeomic fractions. Masses were classified according to molecular weight, unsaturation degree, oxygenation, and presence of nitrogen in the formula. The molecular information obtained with MS was consistent with the physical–chemical properties and environmental condition of the two grassland soils: (i) nitrogenated compounds were generally more numerous and more relatively abundant in the Humeome of Soil B, which was more anoxic and lower in C/N ratio than Soil A, (ii) highly oxygenated compounds were more numerous and abundant in the more oxic Soil A, (iii) most unsaturated formulae were comparatively more abundant in Soil A than Soil B, in line with differences in environmental conditions. The empirical formulae were then matched with their molecular structures, based on the application of ChemSpider and PubChem databases, and were found to be distributed into 16 specific chemical groups. The Van Krevelen plots built on the resulting carbon and nitrogen molecular structures provided a visual comparison of the Humeome of the two soils. The organosoluble fractions in both soils were dominated by aliphatic amides and saccharide ethers, while the hydrosoluble fractions comprised mainly aromatic amides, heterocyclic nitrogen compounds, and saccharide ethers. Conclusions Even though the two soils contained different compounds, 66 molecules were found to be common. Based only on differences in soil texture and oxic conditions, these findings indicate the existence of similar molecular dynamics in the stabilization of organic matter in these two grassland soils. The main common group in the Humeome of both soils was the saccharide ethers, which were additionally bound to aromatic compounds in the hydrosoluble fractions. Our detailed molecular study of the Humeome of these grassland soils confirms the potential of the Humeomic procedure to assess not only the carbon and nitrogen molecular composition in SOM, but also the mechanism of their long-term persistence.

An endophytic bacterium, Serratia marcescens MSRBB2, isolated from inner bark of a Cameroonian Maytenus serrata plant, was subjected to the OSMAC (One Strain Many Compounds) approach and metabolic profiling using HPLC-HRMSn. We identified 7 prodiginines along with 26 serratamolides. Their biosynthetic pathways were elucidated by feeding with labeled precursors in combination with HRMSn. Dual-culture confrontation/restriction assays of the bacterial endophyte were devised with coexisting fungal endophytes (Pestalotiopsis virgatula, Aspergillus caesiellus and Pichia spp.) as well as with unrelated, non-endophytic fungi belonging to the same genera. The assays were combined with scanning electron microscopy (SEM) as well as matrix-assisted laser desorption ionization imaging high-resolution mass spectrometry (MALDI-imaging-HRMS) for visualizing, both in high spatial and temporal resolution, the distribution and interplay of the compounds during microbial interactions. We demonstrated the effect of prodigiosin produced by endophytic S. marcescens MSRBB2 as an allelochemical that specifically inhibits coexisting endophytic fungi. Our results provide new insights into the physiological and ecological relevance of prodiginines and serratamolides within the context of allelopathy and chemical defense interaction occurring between coexisting endophytes harbored in M. serrata.

Tropane alkaloids (TAs), especially hyoscyamine and scopolamine, are important precursors for anticholinergic and antispasmodic drugs. Hyoscyamine and scopolamine are currently obtained at commercial scale from hybrid crosses of Duboisia myoporoides × Duboisia leichhardtii plants. In this study, we present a global investigation of the localization and organization of TA biosynthesis in a Duboisia myoporoides R. Br. wild-type line. The tissue-specific spatial distribution of TAs within D. myoporoides is presented, including quantification of the TAs littorine, 6-hydroxy hyoscyamine, hyoscyamine, scopolamine and, additionally, hyoscyamine aldehyde as well as scopolamine glucoside. Scopolamine (14.77 ± 5.03 mg g-1), and to a lesser extent hyoscyamine (3.01 ± 1.54 mg g-1) as well as 6-hydroxy hyoscyamine (4.35 ± 1.18 mg g-1), are accumulated in leaves during plant development, with the highest concentration of total TAs detected in 6-month-old plants. Littorine, an early precursor in TA biosynthesis, was present only in the roots (0.46 ± 0.07 mg g-1). During development, the spatial distribution of all investigated alkaloids changed due to secondary growth in the roots. Transcripts of pmt, tr-I and cyp80f1 genes, involved in early stages of TA biosynthesis, were found to be most abundant in the roots. In contrast, the transcript encoding hyoscyamine 6β-hydroxylase (h6h) was highest in the leaves of 3-month-old plants. This investigation presents the spatial distribution of biochemical components as well as gene expression profiles of genetic factors known to participate in TA biosynthesis in D. myoporoides. The results of this investigation may aid in future breeding or genetic enhancement strategies aimed at increasing the yields of TAs in these medicinally valuable plant species.

During production of active pharmaceutical ingredients, process waste water is generated at several stages of manufacturing. Whenever possible, the resulting waste water will be processed by conventional waste water treatment plants. Currently, incineration of the process waste water is the method to eliminate compounds with high biological activity. Thus, ozone treatment followed by biological waste water treatment was tested as an alternative method. Two prominent representatives of the large group of fluoroquinolone antibiotics (ciprofloxacin and moxifloxacin) were investigated, focussing on waste water of the bulk production. Elimination of the target compounds and generation of their main transformation products were determined by liquid chromatography - high resolution mass spectrometry (LC-HRMS). The obtained results demonstrated, that the concentration of moxifloxacin and its metabolites can be effectively reduced (>99.7%) prior entering the receiving water. On the contrary, the concentration of ciprofloxacin and its metabolites remained too high for safe discharge, necessitating application of prolonged ozonation for its further degradation. The required ozonation time can be estimated based on the determined kinetics. To assure a low biological activity the ecotoxicity of the ozonated waste water was investigated using three trophic levels. By means of multiple-stage mass spectrometry (MSn) experiments several new transformation products of the fluoroquinolones were identified. Thus, previously published proposed structures could be corrected or confirmed.

The topic to this study is determination of mass spectrometric diffusion parameters “DSD” of oligomeric associates of glycylhomopeptides and their AgI–complexes according to our “stochastic dynamic” approach and model equations under electrospray ionization condition. The problematic has recently gained attenion thanks to the latter formulas connecting among “DSD” data; the measurable outcome “intensity” of analyte ions; and the experimental parameter “temperature,” respectively. The equations are empirically testable and verifiable. In advancing this innovative view upon which models we will carry out analysis of ions of oligomeric associates of peptides, we should point out that it is crucial to further test our formulas on a larger set of chemical classes and experimental conditions in order to verify their universal applicability to different mass spectrometric ionization methods. Because of, on the concept sketched above the DSD parameters correlate excellent linearly with kinetic parameters of fragment reactions and quantum chemical diffusions according to the Arrhenius’s approximation which reflects the 3D molecular structures of analytes. The most important point regarding our concept is that it extends crucially the capability of the mass spectrometry of multidimentional structural analysis when is applied to high accuracy quantum chemical static and molecular dynamic approaches.

There is a straightforward line in the recent development of the functional model connecting the experimental mass spectrometric variable intensity of a peak of an analyte ion with its thermodynamic, kinetic and diffusion parameters. It has been shown that the temporal behavior of the outcome intensity obeys a certain law: ${{\text{D}}_{{\text{SD}}}}{\text{ }} = {\text{ }}1.3193{\text{ }} \times {\text{ }}{10^{ - 14}}{\text{ }} \times {\text{ }}A{\text{ }} \times {\text{ }}{{(\overline {{I^2}} - {{(\bar I)}^2})} \over {{{(I - \bar I)}^2}}}.$ D SD = 1.3193 × 10 − 14 × A × ( I 2 ¯ − ( I ¯ ) 2 ) ( I − I ¯ ) 2 . This formula is universally applicable and empirically testable and verifiable. It connects the intensity with the so-called stochastic dynamic diffusion “DSD” parameter. Its application to small-scale research, so far, using soft-ionization electrospray, atmospheric pressure chemical ionization, matrix-assisted laser desorption/ionization or collision-induced dissociation methods has shown that the DSD parameter is linearly connected with the so-called quantum chemical diffusion parameter “DQC,” obtained within Arrhenius’s theory. Therefore, the DSD parameter connects experimental measurable parameters of ions with their three-dimensional (3D) molecular and electronic structures. The corroborated empirical proof, so far, has convincingly argued that the mass spectrometry appears to be not only a robust instrumentation for highly accurate, precise and selective quantification but also is capable of providing the exact 3D molecular structure of the analytes, when it is used complementary to high accuracy methods of the computational quantum chemistry.

The paper addressed shortcoming with highly precise and selective 3D structural analysis of native cyclodextrins in mixture using ions observable at low m/z–region by ESI– and APCI–mass spectrometry. Because of, the quantitative and structural analyses of CDs, in general, are vexed by a set of complications. The study outlines our own stochastic dynamic approaches to the latter issues based on new model relations, quantifing the measurable MS outcome intensity. They introduce the so–called stochastic dynamic mass spectrometric diffusion “DSD” parameter, exhibiting high accuracy, precision, sensitivity and selectivity, respectively. It is linearly connected with the so–called quantum chemical diffusion parameter “DQC” according to Arrhenius’s theory. The most important upshot is that statistical parameters r = 0.99639–0.99981 has been obtained correlating between DSD and DQC parameters. Therefore, we determine high accurately 3D molecular and electronic structures of analytes by mass spectrometry. Fragment peaks at m/z 313, 279, 272, 252, 231, 214, 198, 171, 158 and 141 are examined. Mixtures of CDs and monomeric and acyclic oligomer carbohydrates glucose (1), sucrose (2), raffinose (3), melezitose (4) and cellotriose (5) are also studied. Our method is able to account precisely for the effect of the temperature under ESI– and APCI–MS conditions, as well. Correlative analysess between DSD parameters of ESI– and APCI–MS measurements under different temperatures is also shown. Chemometric tests are used. Another important results and conclusions, among others, to draw from this research are: (i) excellent linear correlation between DSD and DQC parameters of r = 0.99636 is found looking at common ions at m/z 141, 158 and 171, belonging to 2-formyl-3,4-dihydroxy-pyranylium, 4,5,6-trihydroxy-6H-pyran-2-carbaldehyde and 3,4,5-trihydroxy-6-oxo-6H-pyran-2-ylmethylidyne-oxonium ions. Thus, we distinguish precisely between the last structure and 3-formyl-4,5-dihydroxy-2,7-dioxa-8-oxonia-bicyclo[4.2.0]octa-1(8),3,5-triene cation. In the case of ion at m/z 141 subtle electronic effects are distinguished between the mentioned structure and the charged 3,4-dihydroxy-6H-pyran-2-carbaldehyde one. The method determines precisely very similar structurally poly–OH–substituted derivatives. Because of, (ii) absolute reproducibility (r = 1) of DSD parameters of ESI–MS spectra is obtained studying the shown in point (i) MS peaks of β-CD between jth and jth numbers of experiments. The statistical equation is DiSD = (0.51 ± 3.1.10−5) × DjSD; (iii) the APCI– and ESI–MS provide identical results studying common MS ions of CDs and the correlation between DAPCISD and DESISD parameters excludes from error, due to, experiment; and (iv) The correlation between theory and experiment accounting for the factor temperature within our model equations shows r = 0.9828 looking at the MS peaks at m/z 313 280, 279, 274 and 252, respectively. The effect of the temperature under both ESI– and APCI–MS conditions on the 3D molecular and electronic structures of CDs is precisely studied, respectively.

The first phytochemical investigation of Solandra grandiflora Sw. leaves using LC/MS resulted in the identification without isolation of eight known and one unknown compounds from the neutral and the alkaloidal fractions. Further chromatographic fractionation and isolation of both fractions using RP-HPLC resulted in the isolation of chlorogenic acid, neochlorogenic acid, protocatechuic acid, scopoletin and isoscopoletin from the neutral fraction. Moreover, a new tropinene glycoside identified as 3-O-β-D- glucosyl 6-tropinene, together with atropine, scopolamine and hyoscyamine were isolated from the alkaloidal fraction. The structures of all isolated compounds were established and confirmed by 1H-, 13C-NMR, COSY, HSQC & HMBC spectroscopy, while the exact masses were confirmed by HRESIMS. The cytotoxic activity of all isolates was evaluated against HepG-2, HCT-116, A-549 and MCF-7, and the obtained results suggested selective antiproliferative and cytotoxic effect.

Endophytic bacterial communities harboring different tissues of Maytenus serrata originating from Cameroon were investigated using targeted genome mining techniques coupled to bioanalytical approaches to elucidate the source of maytansine biosynthesis. It was revealed that the host plant, along with its cryptic endophytic microflora, produces the biosynthetically unique core structural moiety 3-amino-5-hydroxybenzoic acid (AHBA) that serves as the unique starter unit for maytansine biosynthesis. However, the biosynthetic step of halogenase-mediated incorporation of chlorine, which is missing in the host plant, is accomplished by the culturable stem endophytic bacterial community. Our results provide new insights into plant-endophyte communication for the biosynthesis of maytansine.

Three new cyclic pentapeptides (1–3) and a known cyclic lipopeptide, fusaristatin A (4), were isolated from an endophytic fungus, Fusarium decemcellulare LG53, harbored in a Chinese medicinal plant Mahonia fortunei. The planar structures of the new compounds were elucidated by extensive spectroscopic analyses using HRMSn and NMR. Their absolute configurations were unambiguously determined by single crystal X-ray diffraction and Marfey's method. Interestingly, compounds 1–3 exhibited no antibacterial activity against a panel of Gram-positive and Gram-negative bacteria. In order to explore the plausible ecological relevance of the compounds within the context of microbial crosstalk and communication strategies, we designed antagonistic and dual-culture assays combined with matrix-assisted laser desorption ionization imaging high-resolution mass spectrometry (MALDI-imaging-HRMS) to investigate the interaction of F. decemcellulare LG53 with another fungal endophyte Glomerella acutata LG52 isolated from the same tissue of the plant. Compound 4 was found to display an allelopathic effect on endophytic G. acutata LG52. Our results provide a proof-of-concept of balanced antagonism that might be occurring between endophytes inhabiting the same plant tissues in distinct ecological niches.

International audience; Bile duct ligation (BDL) is an experimental procedure that mimics obstructive cholestatic disease. One of the early consequences of BDL in rodents is the appearance of so-called bile infarcts that correspond to Charcot-Gombault necrosis in human cholestasis. The mechanisms causing bile infarcts and their pathophysiological relevance are unclear. Therefore, intravital two photon-based imaging of BDL mice was performed with fluorescent bile salts (BS) and non-BS organic anion analogues. Key findings were followed up by matrix-assisted laser desorption ionization imaging, clinical chemistry, immunostaining, and gene expression analyses. In the acute phase, 1-3 days after BDL, BS concentrations in bile increased and single-cell bile microinfarcts occurred in dispersed hepatocytes throughout the liver caused by the rupture of the apical hepatocyte membrane. This rupture occurred after loss of mitochondrial membrane potential, followed by entry of bile, cell death, and a "domino effect" of further death events of neighboring hepatocytes. Bile infarcts provided a trans-epithelial shunt between bile canaliculi and sinusoids by which bile constituents leaked into blood. In the chronic phase, ≥21 days after BDL, uptake of BS tracers at the sinusoidal hepatocyte membrane was reduced. This contributes to elevated concentrations of BS in blood and decreased concentrations in the biliary tract. Conclusion: Bile microinfarcts occur in the acute phase after BDL in a limited number of dispersed hepatocytes followed by larger infarcts involving neighboring hepatocytes, and they allow leakage of bile from the BS-overloaded biliary tract into blood, thereby protecting the liver from BS toxicity; in the chronic phase after BDL, reduced sinusoidal BS uptake is a dominant protective factor, and the kidney contributes to the elimination of BS until cholemic nephropathy sets in. (Hepatology 2019;69:666-683). SEE EDITORIAL ON PAGE 473 R ecently, the concept of an ascending patho-physiology of cholestatic liver disease has been proposed, whereby lesions start in large or small bile ducts followed by the involvement of upstream structures, such as the bile canalicular network and liver parenchyma. (1) Our knowledge of the responses of the biliary tree to cholestasis stems mainly from studies in rodents after bile duct ligation

The basis of chemical crosstalk in plants and associated endophytes lies in certain so-called communication molecules that are responsible for plant-microbe and microbe-microbe interactions. Consequently, elucidating the factors that affect the nature, distribution, and amount of these molecules and how they impact the interaction among endophytes and associated organisms is essential to understand the true potential of endophytes. In the present study, we report the discovery of nine hexacyclopeptides from an endophytic fungus, Fusarium solani, isolated from the bulb of Narcissus tazetta, and their selective accumulation by an endophytic bacterium, Achromobacter xylosoxidans isolated from the same tissue. We used matrix-assisted laser desorption ionization imaging high-resolution mass spectrometry (MALDI-imaging-HRMS) to firstly identify and visualize the spatial distribution of the hexacyclopeptides produced by endophytic F. solani. After culture condition optimization, their sequence was identified to be cyclo((Hyp or Dhp)-Xle-Xle-(Ala or Val)-Thr-Xle) (Dhp: dehydroproline) by the characteristic a, b, or y ions using liquid chromatography tandem mass spectrometry (LC-HRMS(n)). These hexacyclopeptides were confirmed to be fungal biosynthetic products by deuterium labeling experiments. Finally, in order to understand the plausible ecological relevance of one or more of the discovered hexacyclopeptides within the contexts of microbial "neighbor communication," we devised a dual-culture setup to visualize using MALDI-imaging-HRMS how the hexacyclopeptides released by the endophytic fungus are accumulated by another endophytic bacterium, A. xylosoxidans, isolated from the same bulb tissue. This work exemplifies the relevance of cyclopeptides in endophyte-endophyte interspecies neighbor communication occurring in nature. Such communication strategies are evolved by coexisting endophytes to survive and function in their distinct ecological niches.

Advanced analytical imaging techniques, including matrix-assisted laser desorption/ionization high-resolution mass spectrometry (MALDI-HRMS) imaging, can be used to visualize the distribution, localization, and dynamics of target compounds and their precursors with limited sample preparation. Herein we report an application of MALDI-HRMS imaging to map, in high spatial resolution, the accumulation of the medicinally important naphthodianthrone hypericin, its structural analogues and proposed precursors, and other crucial phytochemical constituents in the leaves of two hypericin-containing species, Hypericum perforatum and Hypericum olympicum. We also investigated Hypericum patulum, which does not contain hypericin or its protoforms. We focused on both the secretory (dark glands, translucent glands, secretory canals, laminar glands, and ventral glands) and the surrounding non-secretory tissues to clarify the site of biosynthesis and localization of hypericin, its possible precursors, and patterns of localization of other related compounds concomitant to the presence or absence of hypericin. Hypericin, pseudohypericin, and protohypericin accumulate in the dark glands. However, the precursor emodin not only accumulates in the dark glands but is also present outside the glands in both hypericin-containing species. In hypericin-lacking H. patulum, however, emodin typically accumulates only in the glands, thereby providing evidence that hypericin is possibly biosynthesized outside the dark glands and thereafter stored in them. The distribution and localization of related compounds were also evaluated and are discussed concomitant to the occurrence of hypericin. Our study provides the basis for further detailed investigation of hypericin biosynthesis by gene discovery and expression studies.

Several recent studies have lent evidence to the fact that certain so-called plant metabolites are actually biosynthesized by associated microorganisms. In this work, we show that the original source organism(s) responsible for the biosynthesis of the important anticancer and cytotoxic compound maytansine is the endophytic bacterial community harbored specifically within the roots of Putterlickia verrucosa and P. retrospinosa plants. Evaluation of the root endophytic community by chemical characterization of their fermentation products using HPLC-HRMS(n), along with a selective microbiological assay using the maytansine-sensitive type strain Hamigera avellanea revealed the endophytic production of maytansine. This was further confirmed by the presence of AHBA synthase genes in the root endophytic communities. Finally, MALDI-imaging-HRMS was used to demonstrate that maytansine produced by the endophytes is typically accumulated mainly in the root cortex of both plants. Our study, thus, reveals that maytansine is actually a biosynthetic product of root-associated endophytic microorganisms. The knowledge gained from this study provides fundamental insights on the biosynthesis of so-called plant metabolites by endophytes residing in distinct ecological niches.

The study encompassed experimental mass spectrometric and theoretical quantum chemical studies on adsorption of uranium species in different oxidation states of the metal ion, and oxides of U x O y n + type, where x = 1 or 3, y = 2 or 8, and n = 0, 1 or 2 onto nanosize-particles of saltrock oxides MO (M = Mg II , Ca II , Ni II , Co II , Sr II or Ba II ), M 2 O y (M = Au III or Ag I , y = 3 or 1) silicates 3Al 2 O 3 .2SiO 2 , natural kaolinite (Al 2 O 2 ·2SiO 2 ·2H 2 O), illite (K 0.78 Ca 0.02 Na 0.02 (Mg 0.34 Al 1.69 Fe III 0.02 )[Si 3.35 Al 0.65 ]O 10 (OH) 2 · n H 2 O), CaSiO 3, 3MgO·4SiO 2 ,H 2 O, and M 1 M 2 (SiO 4 )X 2 (M 1 = M 2 = Al or M 1 = K, M 2 = Al, X = F or Cl), respectively. The UV-MALDI-Orbitrap mass spectrometry was utilized in solid-state and semi-liquid colloidal state, involving the laser ablation at λ ex = 337.2 nm. The theoretical modeling and experimental design was based on chemical-, physico-chemical, physical and biological processes involving uranium species under environmental conditions. Therefore, the results reported are crucial for quality control and monitoring programs for assessment of radionuclide migration. They impact significantly the methodology for evaluation of human health risk from radioactive contamination. The study has importance for understanding the coordination and red-ox chemistry of uranium compounds as well. Due to the double nature of uranium between rare element and superconductivity like materials as well as variety of oxidation states ∈ (+1)–(+6), the there remain challenging areas for theoretical and experimental research, which are of significant importance for management of nuclear fuel cycles and waste storage.

Microorganisms are well-known producers of a wide variety of bioactive compounds that are utilized not only for their primary metabolism but also for other purposes such as defense, detoxification, or communication with other micro- and macro-organisms. Natural products containing a 'decalin ring' occur often in microorganisms. They exhibit diverse and remarkable biological activities, including antifungal, antibacterial, anticancer and immunosuppressive activities, to name a few. This review surveys the natural decalin-type compounds that have been isolated from microorganisms, with emphasis on both chemical and biological implications. Total syntheses of some important decalin moiety-containing natural products are also highlighted.

Humeomics encompasses step-wise chemical fractionation and instrumental determination to fully characterize the heterogeneous molecular composition of natural organic matter. Humeomics applied to a terrestrial humic acid produced a recalcitrant end-residue, that was solubilized in alkali and size-fractionated by preparative high performance size exclusion chromatography (HPSEC). The ten separated size-fractions were then subjected to analytical HPSEC hyphenated with a high-resolution electrospray mass spectrometer (ESI-MS). Total ion chromatograms of size-fractions showed two eluting peaks, the molecular masses of which were identified with empirical formulae by ESI-MS. Most empirical formulae were easily associated with linear alkanoic, unsaturated, hydroxylated and hydroxy-unsaturated acids, as well as cyclic acids, but some compound structures were unclear. Tandem MS fragmentation was applied to one linear and three cyclic compounds, to elucidate their structures as hydroxyunsaturated hexanoic acid, two furane rings and a norbornane-like ring, respectively. The latter three compounds were never reported for terrestrial humic acid, but they resembled the carboxyl-rich alicyclic molecules, which had been proposed previously for dissolved organic matter. Quantitative measurement of components indicated that long-chain saturated acids were present in large-sized fractions more than in short-chain homologues, whereas unsaturated, hydroxylated and most cyclic acids were more abundant in small-sized fractions. This suggests that long, saturated and unsubstituted linear acids allow formation of large suprastructures, probably as a result of favorable intermolecular packing, compared with the irregularly shaped cyclic, unsaturated or hydroxylated compounds. We showed that humeomics clarifies the molecular composition and conformational arrangement of natural organic matter, and may help to elucidate the relationship between humic structure and environmental activity.

The paper highlighted AgI- and ZnII-organometallic catalysing C C coupling processes of polysubstituted benzoic acids in polar protic solutions. Six novel interaction products of substituted biphenyl, 6H-benzo-[c]-chromene[6]-one, chromeno[5,4,3-cde]chromene-5,10-dione, and 4,10-dioxa-pyrene-5,9-dione are isolated. The study, therefore impact the fields of inorganic, metal–organic and organometallic chemistry, catalysis, semi-synthetic natural products and materials research, polymer science, and more. The mechanistic aspects of the reactions with participation of nine M C bonded organometallic precursors (M = ZnII, AgI/AgII) and four metal-organic coordination compounds are comprehensively discussed. The factors stabilizing the metal ion – containing systems in polar environment and gas–phase are elucidated, employing the method of quantum chemistry and variety of mass spectrometric approaches, utilizing the ESI-, APCI- and MALDI-methods. These latters provided experimental physical evidences for formation of ZnII and AgI-containing organometallics species with closed d10 shell electronic configuration of the metal ions. The data reported are of methodological importance for the field of the mass spectrometry as well. Due to the matrix-analyte sample preparation techniques in UV–MALDI–MS method widely utilize polysubstituted benzoic acids as organic matrixes. The study contributed as well to the fundamentals of CT- and MLCT-effects in coordination compounds of metal ions with closed d10-electronic configuration. Electronic absorption spectroscopy, single crystal X-ray diffraction and nuclear magnetic resonance methods are also utilized.

A trans cinnamic anhydride (1) isolated for the first time from a natural source, along with the known compounds: ferrulic acid (2), (E) p-hydroxy cinnamic acid (3), clovanediol (4), squalene (5), and α -bisabolene (6) were isolated from the stem bark of Cinnamomum zeylanicum. Their structures were elucidated by interpretation of NMR and MS data, and by comparison of these data with those reported in the literature. Their inhibitory properties were evaluated against Plasmodium falciparum enoyl-ACP reductase (PfENR) enzyme. Compounds 1 , 5 and 6 showed moderate inhibitory activity against P. falciparum enoyl-ACP reductase (PfENR) enzyme.

The Hooker oxidation is one of the most intriguing transformations wherein lapachol (1) is readily converted to norlapachol (2) in very good yield. This one-pot reaction involves a very intricate mechanism in which the alkyl side chain of lapachol is shortened by one carbon unit. Previous studies have unequivocally established the involvement of an indane carboxylic acid derivative 3, as a key intermediate (Hooker intermediate), and its simultaneous conversion to norlapachol (2) via the oxidative cleavage of vicinol diol and subsequent intramolecular aldol reaction of the resulting keto acid. However, the formation of the key Hooker intermediate 3 from lapachol (1) remains ambiguous. The present study has thrown some light on the formation of the key intermediate 3 from lapachol (1) via benzilic acid rearrangement of the corresponding labile o-diquinone intermediate 8 derived from lapachol. The involvement of o-diquinone intermediate 8 in the Hooker oxidation has been further established by trapping of this labile intermediate as the corresponding phenazine derivative 9. The involvement of benzilic acid rearrangement as a key step in the Hooker oxidation is further shown with a variety of o-quinones prepared from lapachol (1). � The Royal Society of Chemistry 2013.

Objectives The objective of this study was to ascertain the presence and correlations among eight important secondary metabolites viz. hypericin, pseudohypericin, emodin, hyperforin, rutin, hyperoside, quercetin and quercitrin in different organs of 17 in vitro cultured Hypericum species, along with H. tomentosum and H. tetrapterum hairy root cultures, and hairy root-derived transgenic plants of H. tomentosum. Methods Samples were extracted and analysed by LC-MS. The LC-MS data were subjected to chemometric evaluations for metabolite profiling and correlating the phytochemical compositions in different samples. Key findings Hypericin, pseudohypericin and their proposed precursor emodin were detected in various levels in the leaves of eight Hypericum species. The highest content of hypericins and emodin was found in H. tetrapterum, which contains the studied secondary metabolites in all plant organs. A significant positive correlation between hypericins and emodin was observed both by principal component analysis (PCA) and multidimensional scaling (MDS), indicating the role of emodin as a possible precursor in the biosynthetic pathway of hypericins. Flavonoids were found in all tested plant organs except roots of H. pulchrum. The hairy roots lacked hypericin, pseudohypericin, emodin, hyperforin and rutin. However, the hairy root-derived transgenic plants showed a significant increase in flavonoids. Conclusions This study broadens knowledge about the phytochemical composition of selected in vitro cultured Hypericum species, compared to that of hairy root cultures and hairy root-derived transgenic plants.

A plethora of plants belonging to the genus Hypericum have been investigated so far owing to the biological efficacies of pharmacologically important secondary metabolites produced by several Hypericum species. However, there is currently a dearth of information about the localization (accumulation) of these compounds in the plants in situ. In particular, the biosynthetic and ecological consequence of acclimatization of in vitro cultured Hypericum spp. to outdoor conditions is not fully known. Herein, we report an application of matrix-assisted laser desorption/ionization high-resolution mass spectrometry (MALDI-HRMS) to reveal the distribution of major naphthodianthrones hypericin, pseudohypericin, protohypericin, and their proposed precursor emodin as well as emodin anthrone, along with the phloroglucinol derivative hyperforin, the flavonoids quercetin, quercitrin, rutin and hyperoside (and/or isoquercitrin), and chlorogenic acid in Hypericum leaves. Plants encompassing seventeen Hypericum species classified into eleven sections, which were first cultured in vitro and later acclimatized to outdoor conditions, were studied. We focused both on the secretory (dark and translucent glands, other types of glands, and glandular-like structures) as well as the non-secretory leaf tissues. We comparatively analyzed and interpreted the occurrence and accumulation of our target compounds in different leaf tissues of the seventeen species to get an intra-sectional as well as inter-sectional perspective. The naphthodianthrones, along with emodin, were present in all species containing the dark glands. In selected species, hypericin and pseudohypericin accumulated not only in the dark glands, but also in translucent glands and non-secretory leaf tissues. Although hyperforin was localized mainly in translucent glands, it was present sporadically in the dark glands in selected species. The flavonoids quercetin, quercitrin, and hyperoside (and/or isoquercitrin) were distributed throughout the leaves. Rutin was present only within sections Hypericum, Adenosepalum, Ascyreia, and Psorophytum. Our study provides insights into the prospects and challenges of using in vitro cultured Hypericum plants, further adapted to field conditions, for commercial purposes.

Three new compounds, colletotrichones A-C (1-3), and one known compound, chermesinone B (4a), were isolated from an endophytic fungus, Colletotrichum sp. BS4, harbored in the leaves of Buxus sinica, a well-known boxwood plant used in traditional Chinese medicine (TCM). Their structures were determined by extensive spectroscopic analyses including 1D and 2D NMR, HRMS, ECD spectra, UV, and IR, as well as single-crystal X-ray diffraction, and shown to be azaphilones sharing a 3,6a-dimethyl-9-(2-methylbutanoyl)-9H-furo[2,3-h]isochromene-6,8-dione scaffold. Owing to the remarkable antibacterial potency of known azaphilones coupled to the usage of the host plant in TCM, we evaluated the antibacterial efficacy of the isolated compounds against two commonly dispersed environmental strains of Escherichia coli and Bacillus subtilis, as well as against two human pathogenic clinical strains of Staphylococcus aureus and Pseudomonas aeruginosa. Compound 1 exhibited marked antibacterial potencies against the environmental strains that were comparable to the standard antibiotics. Compound 3 was also active against E. coli. Finally, compound 2a exhibited the same efficacy as streptomycin against the clinically relevant bacterium S. aureus. The in vitro cytotoxicity of these compounds on a human acute monocytic leukemia cell line (THP-1) was also assessed. Our results provide a scientific rationale for further investigations into endophyte-mediated host chemical defense against specialist and generalist pathogens.