The UV–Vis absorption spectrum for the flowers of red frangipani extract shown in Fig. 2 reveals the absorption between 450 and 600 nm with absorption maxima at 530 nm. Recent investigations
indicated that anthocyanins are responsible for the attractive colors of the flowers of red frangipani with absorption maxima at 520 nm [17]. High-resolution liquid chromatography–mass spectrometry (LC–MS) investigations on the extract of red frangipani flower indicates signals of molecular ions (M+) at m/z 611 and 449 as shown in Fig. 3, which agrees well with the earlier high resolution liquid chromatography–electrospray mass spectrometry (ESI+/TOF) studies [17]. Byamukama et al. predicted that the molecular ion observed at m/z 611.1581 corresponds to cyanidin