RESUMO
Glycosidically bound aroma compounds in three different types of tobacco were investigated. After isolation of extracts obtained by Amberlite XAD-2 adsorption and ethyl acetate elution, glycosides were analyzed after enzymatic hydrolysis by gas chromatography-mass spectrometry (GC-MS) or directly after trifluoroacetylated (TFA) derivatization by GC-MS in electron ionization (EI) and negative chemical ionization (NCI) mode. In total 21 bound aglycones were identified by ß-glucosidase hydrolysis. These aglycones mainly consisted of C13-norisoprenoids, aromatic components and sesquiterpenoids. Additionally, with the aid of enzymatic hydrolysis, 15 ß-d-glucopyranosides and 1 ß-d-rutinoside were tentatively identified by TFA derivatization. TFA method was validated by repeatability and successfully employed to analyze different types of tobacco. Principal component analysis (PCA) was carried out on identified glycoside variables to visualize the difference between the tobacco types and the relationship between the glycoside variables and the tobacco types was established.
Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Glicosídeos/análise , Nicotiana/química , Odorantes/análise , Extratos Vegetais/química , Análise de Componente Principal , Reprodutibilidade dos TestesRESUMO
One new limonoid, toonaciliatone A (1), and one new tirucallane-type triterpenoid, toonaciliatine A (4), along with three known compounds, methyl-3beta-acetoxy-1-oxomelic-14(15)-enate (2), perforin A (3), and cholest-14-ene-3,7,24,25-tetrol-21,23-epoxy-21-methoxy-4,4,8-trimethyl-3-(3-methyl-2-butenoate) (5), were isolated from the leaves of Toona ciliata. The structures of the new compounds were established by spectroscopic methods.
Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Limoninas/isolamento & purificação , Meliaceae/química , Triterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Limoninas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Triterpenos/químicaRESUMO
Seven known and six new tetranortriterpenoids, cineracipadesins A-F (1-6), were isolated from the leaves of Cipadessa cinerascens. Compound 1 has a mexicanolide-type structural skeleton with a rare 9alpha,11alpha-epoxide ring; compound 2 has a methyl angolensate-type structure with 9,11-dihydroxy groups, representing the first example of a precursor of a trijugin-type limonoid; and 3 is the first reported methyl angolensate-type limonoid with a ketone group at ring C. Their structures were determined with extensive spectroscopic analysis. X-ray crystallography confirmed the structure of 1. The ability of compounds 1-7 to inhibit the growth of the P-388 murine leukemia cell line was evaluated.