Metabolic Changes in Different Developmental Stages of Vanilla planifolia Pods
Résumé
The metabolomic anal. of developing Vanilla planifolia green pods (between 3 and 8 mo after pollination) was carried out by NMR spectroscopy and multivariate data anal. Multivariate data anal. of the 1H NMR spectra, such as principal component anal. (PCA) and partial least-squares-discriminant anal. (PLS-DA), showed a trend of sepn. of those samples based on the metabolites present in the methanol/water (1:1) ext. Older pods had a higher content of glucovanillin, vanillin, p-hydroxybenzaldehyde glucoside, p-hydroxybenzaldehyde, and sucrose, while younger pods had more bis[4-(β-D-glucopyranosyloxy)-benzyl]-2-isopropyltartrate (glucoside A), bis[4-(β-D-glucopyranosyloxy)-benzyl]-2-(2-butyl)tartrate (glucoside B), glucose, malic acid, and homocitric acid. A liq. chromatog.-mass spectrometry (LC-MS) anal. targeted at phenolic compd. content was also performed on the developing pods and confirmed the NMR results. Ratios of aglycons/glucosides were estd. and thus allowed for detection of more minor metabolites in the green vanilla pods. Quantification of compds. based on both LC-MS and NMR analyses showed that free vanillin can reach 24% of the total vanillin content after 8 mo of development in the vanilla green pods. [on SciFinder(R)]