RESUMEN
Two beta-D-glucopyranosides and two 6-O-beta-D-apiofuranosyl-beta-D-glucopyranosides of (E)-6,9-dihydroxymegastigma-4,7-dien-3-one were isolated from Vitis vinifera cv. Gewürztraminer wine and their structures were established by NMR spectroscopy.
Asunto(s)
Frutas/química , Glicósidos/aislamiento & purificación , Vino/análisis , Conformación de Carbohidratos , Cromatografía de Gases y Espectrometría de Masas , Glicósidos/química , Espectroscopía de Resonancia MagnéticaRESUMEN
Eight glycosides and a phenylpropanoid glycerol were isolated from Vitis vinifera cv. Gewurztraminer wine, and their structures were elucidated by MS and NMR spectroscopies. cis-1-(5-Ethenyl-5-methyltetrahydrofuran-2-yl)-1-methylethyl O-beta-D-apiofuranosyl-(1-->6)-O-beta-D-glucopyranoside, (E)-3,6, 9-trihydroxymegastigm-7-ene 9-O-beta-D-glucopyranoside, 2-phenylethyl O-beta-D-apiofuranosyl-(1-->6)-O-beta-D-glucopyranoside, and 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]propane-1,3-diol are reported for the first time as wine components.
Asunto(s)
Glicerol/aislamiento & purificación , Glicósidos/aislamiento & purificación , Rosales/química , Vino/análisis , Espectroscopía de Resonancia Magnética , Espectrometría de MasasRESUMEN
The organic matter found in sedimentary rocks must derive from many sources; not only from ancient primary producers but also from consumers and secondary producers. In all of these organisms, isotope effects can affect the abundance and distribution of 13C in metabolites. Here, by using an improved form of a previously described technique in which the effluent of a gas chromatograph is continuously analysed isotopically, we report evidence of the diverse origins of sedimentary organic matter. The record of 13C abundances in sedimentary carbonate and total organic carbon can be interpreted in terms of variations in the global carbon cycle. Our results demonstrate, however, that isotope variations within sedimentary organic mixtures substantially exceed those observed between samples of total organic carbon. Resolution of isotope variations at the molecular level offers a new and convenient means of refining views both of localized palaeoenvironments and of control mechanisms within the global carbon cycle.