Production of Rare Phyto-Ceramides from Abundant Food Plant Residues

Ceramides (Cers) are major components of the outermost layer of the skin, the stratum corneum, and play a crucial role in permeability barrier functions. Alterations in Cer composition causing skin diseases are compensated with semisynthetic skin-identical Cers. Plants constitute new resources for Cer production as they contain glucosylceramides (GluCers) as major components. GluCers were purified from industrial waste plant materials, apple pomace (<i>Malus domestica</i>), wheat germs (<i>Triticum</i> sp.), and coffee grounds (<i>Coffea</i> sp.), with GluCer contents of 28.9 mg, 33.7 mg, and 4.4 mg per 100 g of plant material. Forty-five species of GluCers (<b>1</b>–<b>45</b>) were identified with different sphingoid bases, saturated or monounsaturated α-hydroxy fatty acids (C15–28), and β-glucose as polar headgroup. Three main GluCers were hydrolyzed by a recombinant human glucocerebrosidase to produce phyto-Cers (<b>46</b>–<b>48</b>). These studies showed that rare and expensive phyto-Cers can be obtained from industrial food plant residues

Structure and Absolute Configuration of Pseudohygrophorones A¹² and B¹², Alkyl Cyclohexenone Derivatives from <i>Hygrophorus abieticola </i>(Basidiomycetes)

Pseudohygrophorones A¹² (<b>1</b>) and B¹² (<b>2</b>), the first naturally occurring alkyl cyclohexenones from a fungal source, and the recently reported hygrophorone B¹² (<b>3</b>) have been isolated from fruiting bodies of the basidiomycete <i>Hygrophorus abieticola</i> Krieglst. ex Gröger & Bresinsky. Their structures were assigned on the basis of extensive one- and two-dimensional NMR spectroscopic analysis as well as ESI-HRMS measurements. The absolute configuration of the three stereogenic centers in the diastereomeric compounds <b>1</b> and <b>2</b> was established with the aid of ³<i>J</i>_H,H and ⁴<i>J</i>_H,H coupling constants, NOE interactions, and conformational analysis in conjunction with quantum chemical CD calculations. It was concluded that pseudohygrophorone A¹² (<b>1</b>) is 4<i>S</i>,5<i>S</i>,6<i>S</i> configured, while pseudohygrophorone B¹² (<b>2</b>) was identified as the C-6 epimer of <b>1</b>, corresponding to the absolute configuration 4<i>S</i>,5<i>S</i>,6<i>R</i>. In addition, the mass spectrometric fragmentation behavior of <b>1</b>–<b>3</b> obtained by the higher energy collisional dissociation method allows a clear distinction between the pseudohygrophorones (<b>1</b> and <b>2</b>) and hygrophorone B¹² (<b>3</b>). The isolated compounds <b>1</b>–<b>3</b> exhibited pronounced activity against phytopathogenic organisms

Discovering Regulated Metabolite Families in Untargeted Metabolomics Studies

The identification of metabolites by mass spectrometry constitutes a major bottleneck which considerably limits the throughput of metabolomics studies in biomedical or plant research. Here, we present a novel approach to analyze metabolomics data from untargeted, data-independent LC-MS/MS measurements. By integrated analysis of MS¹ abundances and MS/MS spectra, the identification of regulated metabolite families is achieved. This approach offers a global view on metabolic regulation in comparative metabolomics. We implemented our approach in the web application “MetFamily”, which is freely available at http://msbi.ipb-halle.de/MetFamily/. MetFamily provides a dynamic link between the patterns based on MS¹-signal intensity and the corresponding structural similarity at the MS/MS level. Structurally related metabolites are annotated as metabolite families based on a hierarchical cluster analysis of measured MS/MS spectra. Joint examination with principal component analysis of MS¹ patterns, where this annotation is preserved in the loadings, facilitates the interpretation of comparative metabolomics data at the level of metabolite families. As a proof of concept, we identified two trichome-specific metabolite families from wild-type tomato <i>Solanum habrochaites</i> LA1777 in a fully unsupervised manner and validated our findings based on earlier publications and with NMR

Soft Corals Biodiversity in the Egyptian Red Sea: A Comparative MS and NMR Metabolomics Approach of Wild and Aquarium Grown Species

Marine life has developed unique metabolic and physiologic capabilities and advanced symbiotic relationships to survive in the varied and complex marine ecosystems. Herein, metabolite composition of the soft coral genus <i>Sarcophyton</i> was profiled with respect to its species and different habitats along the coastal Egyptian Red Sea via ¹H NMR and ultra performance liquid chromatography-mass spectrometry (UPLC–MS) large-scale metabolomics analyses. The current study extends the application of comparative secondary metabolite profiling from plants to corals revealing for metabolite compositional differences among its species via a comparative MS and NMR approach. This was applied for the first time to investigate the metabolism of 16 <i>Sarcophyton</i> species in the context of their genetic diversity or growth habitat. Under optimized conditions, we were able to simultaneously identify 120 metabolites including 65 diterpenes, 8 sesquiterpenes, 18 sterols, and 15 oxylipids. Principal component analysis (PCA) and orthogonal projection to latent structures-discriminant analysis (OPLS) were used to define both similarities and differences among samples. For a compound based classification of coral species, UPLC–MS was found to be more effective than NMR. The main differentiations emanate from cembranoids and oxylipids. The specific metabolites that contribute to discrimination between soft corals of <i>S. ehrenbergi</i> from the three different growing habitats also belonged to cembrane type diterpenes, with aquarium <i>S. ehrenbergi</i> corals being less enriched in cembranoids compared to sea corals. PCA using either NMR or UPLC–MS data sets was found equally effective in predicting the species origin of unknown <i>Sarcophyton</i>. Cyclopropane containing sterols observed in abundance in corals may act as cellular membrane protectant against the action of coral toxins, that is, cembranoids

Chilenopeptins A and B, Peptaibols from the Chilean <i>Sepedonium</i> aff. <i>chalcipori</i> KSH 883

The Chilean <i>Sepedonium</i> aff. <i>chalcipori</i> strain KSH 883, isolated from the endemic <i>Boletus loyo</i> Philippi, was studied in a polythetic approach based on chemical, molecular, and biological data. A taxonomic study of the strain using molecular data of the ITS, EF1-α, and RPB2 barcoding genes confirmed the position of the isolated strain within the <i>S. chalcipori</i> clade, but also suggested the separation of this clade into three different species. Two new linear 15-residue peptaibols, named chilenopeptins A (<b>1</b>) and B (<b>2</b>), together with the known peptaibols tylopeptins A (<b>3</b>) and B (<b>4</b>) were isolated from the semisolid culture of strain KSH 883. The structures of <b>1</b> and <b>2</b> were elucidated on the basis of HRESIMS^<i>n</i> experiments in conjunction with comprehensive 1D and 2D NMR analysis. Thus, the sequence of chilenopeptin A (<b>1</b>) was identified as Ac-Aib¹-Ser²-<b><u>Trp</u></b>^<b>3</b>-Aib⁴-Pro⁵-Leu⁶-Aib⁷-Aib⁸-Gln⁹-Aib¹⁰-Aib¹¹-Gln¹²-Aib¹³-Leu¹⁴-Pheol¹⁵, while chilenopeptin B (<b>2</b>) differs from <b>1</b> by the replacement of Trp³ by Phe³. Additionally, the total synthesis of <b>1</b> and <b>2</b> was accomplished by a solid-phase approach, confirming the absolute configuration of all chiral amino acids as l. Both the chilenopeptins (<b>1</b> and <b>2</b>) and tylopeptins (<b>3</b> and <b>4</b>) were evaluated for their potential to inhibit the growth of phytopathogenic organisms