Metabolomic discrimination of the edible mushrooms Kuehneromyces mutabilis and Hypholoma capnoides (Strophariaceae, Agaricales) by NMR spectroscopy

Two edible, cultivable mushroom species of the family Strophariaceae, Kuehneromyces mutabilis (sheathed woodtuft) and Hypholoma capnoides (conifer tuft), were studied using proton nuclear magnetic resonance metabolomic approach. The variation in the metabolites of the two species and their metabolic behaviourregarding caps and stipes and different collection sites were analysed by multivariate analysis methods. Altogether 169 cap and stipe samples of the mushrooms were investigated. The clearest difference between the species was in the sugar composition, which was more diverse in H. capnoides. When mushroom samples collected from different locations were compared, more variance was found in H. capnoides, whereas K. mutabilis appeared more homogeneous as a species. As far as the caps and stipes were concerned, in both species the amount of α-α-trehalose was clearly higher in the stipes, and the caps contained a larger proportion of the amino acids and organic acids.</p

Systematic study of the physicochemical properties of a homologous series of aminobisphosphonates

ABSTRACT: Aminobisphosphonates, e.g., alendronate and neridronate, are a well known class of molecules used as drugs for various bone diseases. Although these molecules have been available for decades, a detailed understanding of their most important physicochemical properties under comparable conditions is lacking. In this study, ten aminobisphosphonates, H2N(CH2)nC(OH)[P(O)(OH)2]2, in which n = 2-5, 7-11 and 15 have been synthesized. Their aqueous solubility as a function of temperature and pH, pKa-values, thermal stability, IR absorptions, and NMR spectral data for both liquid (1H, 13C, 31P-NMR) and solid state (13C, 15N and 31P-CPMAS NMR) were determined.Peer reviewe

Phenolic compounds extracted by acidic aqueous ethanol from berries and leaves of different berry plants

Phenolic compounds of berries and leaves of thirteen various plant species were extracted with aqueousethanol and analyzed with UPLC-DAD-ESI-MS, HPLC-DAD, and NMR. The total content of phenolics wasconsistently higher in leaves than in berries (25–7856 vs. 28–711 mg/100 g fresh weight). Sea buckthornleaves were richest in phenolic compounds (7856 mg/100 g f.w.) with ellagitannins as the dominant compoundclass. Sea buckthorn berries contained mostly isorhamnetin glycosides, whereas quercetin glycosideswere typically abundant in most samples investigated. Anthocyanins formed the dominating groupof phenolics in most dark-colored berries but phenolic acid derivatives were equally abundant in saskatoonand chokeberry berries. Caffeoylquinic acids constituted 80% of the total phenolic content(1664 mg/100 g f.w.) in bilberry leaves. B-type procyanidins and caffeoylquinic acids were the major phenoliccompounds in hawthorn and rowanberry, respectively. Use of leaves of some species with prunasin,tyramine and b-p-arbutin, may be limited in food applications.</p

Flavonol Glycosides in Currant Leaves and Variation with Growth Season, Growth Location, and Leaf Position

Flavonol glycosides (FG) were analyzed in the leaves of six currant cultivars (Ribes spp.) with HPLC-DAD, HPLC-MS/MS, and NMR. The average amounts of the 12 major, identified FG constituted 86–93% (9.6–14.1 mg/g DW) of the total of 27 FG found. Quercetin and kaempferol were the major aglycones with trace amounts of myricetin. Quercetin-3-<i>O</i>-(2,6-α-dirhamnopyranosyl-β-glucopyranoside), quercetin-3-<i>O</i>-(2-β-xylopyranosyl-6-α-rhamnopyranosyl-β-glucopyranoside), and kaempferol-3-<i>O</i>-(3,6-α-dirhamnopyranosyl-β-glucopyranoside) were identified for the first time in currant leaves and existed in a white currant cultivar ‘White Dutch’ only. Kaempferol-3-<i>O</i>-β-(6′-malonyl)­glucopyranoside was also a new compound existing in abundance in five cultivars but not in the white one. The results show the primary importance of the genetic background of the cultivars. The content of malonylated FG of special importance in cardiovascular health decreased regularly during summer. Time of collection and leaf position were more prominent factors affecting the composition than were the year of harvest or the growth latitude. Randomly collected leaves differed in their FG profiles from those collected from the middle position of new branches

Stability of Hydroxycinnamic Acid Derivatives, Flavonol Glycosides, and Anthocyanins in Black Currant Juice

The stability of phenolic compounds was followed in black currant juice at ambient temperatures (in light and in dark conditions) and at +4 °C for a year. Analyses were based on high-performance liquid chromatography–diode-array detection–electrospray ionization–mass spectrometry (or tandem mass spectrometry) and high-performance liquid chromatography–diode-array detection–electrospray ionization–quadrupole time-of-flight mass spectrometry methods supported by nuclear magnetic resonance after selective high-performance liquid chromatography isolation. Altogether, 43 metabolites were identified, of which 2-(<i>Z</i>)-<i>p</i>-coumaroyloxymethylene-4-β-d-glucopyranosyloxy-2-(<i>Z</i>)-butenenitrile, 2-(<i>E</i>)-caffeoyloxymethylene-4-β-d-glucopyranosyloxy-2-(<i>Z</i>)-butenenitrile, 1<i>-O-</i>(<i>Z</i>)<i>-p</i>-coumaroyl-β-d-glucopyranose, (<i>Z</i>)<i>-p-</i>coumaric acid 4-<i>O</i>-β-d-glucopyranoside, and (<i>Z</i>)-<i>p</i>-coumaric acid were novel findings in black currant juice. Hydroxycinnamic acid derivatives degraded 20–40% at room temperature during one year of storage, releasing free hydroxycinnamic acids. <i>O</i>-Glucosides of hydroxycinnamic acid compounds were the most stable, followed by <i>O</i>-acylquinic acids, acyloxymethyleneglucosyloxybutenenitriles, and <i>O</i>-acylglucoses. Light induced the isomerization of (<i>E</i>)-coumaric acid compounds into corresponding <i>Z</i>-isomers. Flavonol glycosides stayed fairly stable. Flavonol aglycones were derived mainly from malonylglucosides. Over 90% of anthocyanins were lost at room temperature in a year, practically independent of light. Storage at low temperatures, preferably excluding light, is necessary to retain the original composition of phenolic compounds