Anthocyanins from ornamental flowers of red frangipani, Plumeria rubra

Two anthocyanins were isolated from ornamental reddish flowers of Plumeria rubra L. (Apocynaceae) by a combination of chromatographic techniques. Their structures were elucidated mainly by the use of homo- and heteronuclear nuclear magnetic resonance spectroscopy and high-resolution electrospray mass spectrometry. The anthocyanin cyanidin 3-O-β-(2″-glucopyranosyl-O-β-galactopyranoside) (75%), has previously been isolated only from Cornus suecica (Cornaceae) fruits, while the other (20%) was identified as cyanidin-3-O-β-galactopyranoside. This is the first report of the anthocyanins responsible for the attractive colours of the flowers of red frangipani.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► We isolated the anthocyanic pigments of ornamental red frangipani (Plumeria) flowers. ► 3-(2″-glucosylgalactoside) (75%) and 3-galactoside (20%) of cyanidin were found. ► The former pigment has previously been identified only in Cornus suecica (Cornaceae).