The major factors responsible for colour variation in a range of Pelar
gonium species and cultivars were shown to be the types and relative l
evels of pigments present. Variations in pH and copigment levels were
not found to contribute significantly. Flowers with colours ranging fr
om cream and pink through to deep purple, including salmon, orange and
red, were studied. While either flavonols or carotenoids were respons
ible for cream/yellow colouration, all other colours resulted from ant
hocyanin mixes. The pigments were isolated, quantified and identified
by combinations of column and HPL chromatography, absorption spectrosc
opy and NMR. The major anthocyanins were identified as the 3,5-digluco
sides and 3-glucoside-5-(6-acetyl)glucosides of pelargonidin, cyanidin
, peonidin, delphinidin, petunidin and malvidin. The acetates, four of
which have not been reported previously, were found predominantly in
the regal Pelargonium cultivars. (C) 1997 Elsevier Science Ltd. All ri
ghts reserved.