An integrated analytical approach for the compositional evaluation of different stages of fully ripened Jatropha curcas seed oil

摘要

The present study aims to determine the compositional changes including physicochemical characterization of Jatropha seed oil at three different stages of ripening (green: JO-I; yellow: JO-II; and brown: JO-III). The moisture and oil content of Jatropha seeds was 60.83-10.12% and 34-32 (wt%) for JO-I to JO-III stages, respectively. The moisture content and acid value (mg KOH/g) of the oil was 8.88-4.05% and 0.62-2.86. Fatty acid composition (wt%) of the oil (JO-I-III stage) showed that palmitic (C-16:0) acid decreases from 16.98 to 14.40 while as stearic (C-18:0) acid increases from 7.19 to 7.57. The content of the monounsaturated acid (wt%) oleic (9-cis C-18:1) acid was 53.13, 41.96, and 60.93, while a diunsaturated acid, linoleic (9-cis 12-cis C-18:2) acid, was 12.39, 32.52, and 14.93 in the JO-I to JO-III stages respectively, which was also confirmed by H-1 NMR. The percentage of diunsaturated (9-cis 12-cis C-18:2) acid follows a reverse trend to the monounsaturated (9-cis C-18:1) acid. The stage JO-II (yellow) seems to be a turning point in the seed development. The studies also revealed the presence of sterol glucosides in early stage (JO-I) of seed development; which declined at later stages. The results showed that variation in fatty acid composition together with the physicochemical properties can be helpful in understanding the biosynthesis of seed development.