PIGMENT CHEMISTRY AND COLOR OF PELARGONIUM FLOWERS

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.