literature [21,22].
No significant shift was observed in the absorption spectrum of
ivy gourd fruit extract adsorbed onto TiO2 surface as shown in
Fig. 1. This may be due to the absence of binding groups such as hydroxyl
or carboxylic groups in b-carotene.
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 3-O-b-(200-glucopyranosyl-O-b-galactopyranoside) with the empirical
formula C27H31O16 and the molecular ion observed at m/z
449.1068 corresponds to cyanidin-3-O-b-galactopyranoside with
the empirical formula C21H21O11 [17]