Variations in Carotenoid Profiles of Pulp Morphological Fruit Types of Palmyrah from Kalpitiya

Abstract

Depending on the morphology of fruit, palmyrah (Borassus flabellifer) had been classified in 5 types. On extraction, total carotenoid of the types from Kalpitiya was found to vary from 3.3-9.3 mg.lnug' fresh weight. On separation by open column chromatography using a solvent gradient, carotenoids of the 5 types of fruit were found to vary markedly. Type Iwas dom inated by violaxanthin and neoxanthin, type IIA by neoxanthin, ~-zeacarotene, violaxanthin and phytofluene, type lIB by phytoene, phytofluene, violaxanthin and neoxanthin, Type III by phytoene and violaxanthin and type IV by phytofluene and zeta-carotene. Of the nine carotenoids isolated only ~-carotene and ~-zeacarotene are provitamin A. The 5 types gave varying retinol equivalent 18, 155,32,21 and 33 per 100g on fresh weight basis for types I to IV respectively. The carotenoid profile differed from those of the same types previously collected from Mannar with the carotenoid content five to twelve fold more in the latter, However a common feature was that lycopene and compounds of the right fork of the carotenoid biosynthesis pathway were not detected from all types except the uncommon type IV (found only in Kalpitiya), indicating that the main types had a similar genetic overall biosynthetic motif. The variation of contents of the individual components of the left fork from location to location could be influenced by climatic and edaphic factors too. Type IV which had considerable morphological differences appears much less related to the other types.