Identification of Novel Glycosidic Aroma Precursors in Saffron (Crocus sativus L.)

The methanolic extract of saffron was separated with the aid of multilayer coil countercurrent chromatography. After purification by HPLC, the following seven novel carotenoid metabolites were identified on the basis of their spectral (UV, FTIR, MS, NMR, CD) data: (4R)-4-hydroxy-2,6,6-trimethylcyclohex-1-enecarbaldehyde O-β-d-gentiobioside (1), (4R)-4-hydroxy-2,6,6-trimethylcyclohex-1-enecarboxylic acid O-β-d-glucopyranoside (2), 6-hydroxy-3-(hydroxymethyl)-2,4,4-trimethylcyclohexa-2,5-dienone 6-O-β-d-glucopyranoside (3), (2Z)-3-methylpent-2-enedioic acid 1-[1-(2,4,4-trimethyl-3,6-dioxocyclohexenyloxy)-O-β-d-glucopyranosid-6-yl] ester (4), (5S)-5-hydroxy-7,7-dimethyl-4,5,6,7-tetrahydro-3H-isobenzofuran-1-one O-β-d-glucopyranoside (5), (1R,5S,6R)-5-(hydroxymethyl)-4,4,6-trimethyl-7-oxabicyclo[4.1.0]heptan-2-one O-β-d-glucopyranoside (6), and (1R)- 3,5,5-trimethylcyclohex-3-enol O-β-d-glucopyranoside (7). Keywords: Carotenoid metabolites; glycosides; aroma precursor; multilayer coil countercurrent chromatography; saffron; Crocus sativus