CHEMICAL-COMPOSITION OF OILS OF PUMPKIN, GOURD, MELON

Abstract

Highly unsaturated oils can be extracted from seeds of plants belonging to the Cucurbitaceae family, gourd (50%), pumpkin (37%) and melon (34%). The fatty acids of these oils are palmitic (10.5-12.2%), stearic (4.8-5.9%), oleic (12.6-34.9%), linoleic(45.4-71.4%) and beta-eleostearic (0.7%) acids. The tocopherol content of these oils is high (655-1270 mg/kg), mainly in gamma isomer. The triglycerid content have been analysed. Gourd and melon seed oils are rich in LLL, OLL and PLL, while pumpkin oil contains also OOL and POL. The unsaponifiable matter was chromatographied on an alumina column, then fractionated by HPLC and CCM on pure or AgNO3 impregnated silica, giving eight triterpenic alcohols, four 4-methylsterols, three DELTA-5 sterols and five DELTA-7 sterols which were rigorously identified by mass spectrometry and proton NMR (Table VIII). Some of these rarely found triterpenic compounds are specific of Cucurbitaceae seeds.