Simultaneous qualitative and quantitative analysis of phenanthrene derivatives in Vanda coerulea by LC-HRMS/MS

Previous phytochemical analyses of crude extracts of Vanda coerulea Griff ex. Lindl (Orchidaceae) have led to the identification of stem-specific metabolites. In total, one hydroxy-benzyl acid and 5 chemically diverse phenanthrene derivatives were identified, including one bibenzyl, two phenanthropyrans and two dihydrophenanthrenes. These six compounds were identified for the first time together in one species and are considered as V. coerulea chemical markers. The three most concentrated compounds (imbricatin, methoxycoelonin and gigantol) displayed antioxidant and skin anti-inflammatory activities and can thus be considered also as biomarkers [1].

Different studies have been led to identify in which vegetative stage (plants with bud, before or during flowering) these metabolites are the most concentrated. The quantitative analysis was performed by a LC-HRMS/MS developed and validated method. For practical reasons, this study was conducted on a population of V. coerulea cultivated in a green house.

Notable differences were observed among the different vegetative stages. In February, they are concentrated in flowering plants then their amount increase in October. In every case, V. coerulea specimens in bud contain the least metabolites of interest. The developed method permitted to better control a cultivated population of orchids in an artificial environment. If our results are confirmed on wild population growing in a natural biotope, we can determine in the future the optimal conditions of collecting the high-value added plant material for industrial valorization.

References:

[1] Simmler C., Antheaume C., Lobstein A.: PlosOne. 2010 Oct 28;5(10):e13713.