Oil, Fatty Acid Profile and Karanjin Content in Developing Pongamia pinnata (L.) Pierre Seeds

Abstract

Oil content, fatty acid composition and karanjin content were studied in developing pongamia seeds, at intervals of 3 weeks from 30 weeks after flowering up to 42 weeks. Three marked stages in seed development were observed at the early green pod stage, the middle half brown stage and the late dark brown stage. Significant variation in seed biomass, pod and seed characteristics were observed. A significant (P \ 0.01) decrease in the moisture content of the seeds was observed during seed development. The oil content gradually increased from 32.06 to 36.53 % as the seed matured. A significant variation in fatty acid composition was detected across all stages of seed development. Palmitic acid (16:0) content marginally decreased from 11.81 to 10.18 %, while stearic acid (18:0) and linolenic acid (18:3) remained constant at all stages of seed maturity. A steady increase in oleic acid (18:1) content from 38.11 to 49.11 % was observed, while the linoleic acid (18:2) content decreased from 30.14 to 18.85 %. The iodine value increased, while the saponification number of oil decreased during seed development. The increase in karanjin content was steady. Seeds harvested after 42 week after flowering yielded the maximum oil with high oleic acid content which could be suitable for biodiesel production. KeywordsFatty acid profile Á Karanjin Á Oil content Á Pongamia pinnata Á Seed development Abbreviations WAF Weeks after flowering FAME Fatty acid methyl esters DMRT Duncan multiple range test MC

Localisation of Storage Reserves in Developing Seeds of Pongamia pinnata (L.) Pierre, a Potential Agroforestry Tree

“…The diameter of the oil bodies observed in pongamia seed was at par with the other diverse species [7]. The diameter of the oil bodies (0.3 to 1.2 lm) was correlated to the high oil content of the mature seed (36.53 %) [13]. The correlation between high oil content and small oil bodies was also reported in Brassica napus [38].…”

“…The previous study on pongamia showed that pod length and breadth did not vary much however the pod thickness, seed length, breadth and thickness increased from 30 to 42 WAF. The oil content increased with seed maturity and the oleic acid content remained high at the end of pod maturity while karanjin content varied significantly across different stages of pongamia seed development [13]. Localisation of seed storage reserves in pongamia showed a marked compartmentation similar to that observed in Phaseolus vulgaris [10].…”

“…According to Taiz and Zeiger [30] lignin is associated mainly with the hemicellulose in seed coat layer ensuring the protective survival of the offspring by maintaining an environment around the embryo during the extreme conditions. As the moisture content of developing seed is reduced to 14 % at the time of physiological maturity (42 WAF) [13], the seed coat cells shrink with the progress of seed maturity and the seed surface becomes rough and brown. The browning of the seed coat could be attributed to condensation of tannins as reported in other legume seeds [31].…”

“…The information on the developmental stages of pongamia seed and the determination of the proper stage for seed harvesting is lacking in the literature. In a previous study, an ideal time for harvesting of mature pongamia fruits was identified as 42 weeks after flowering (WAF) when the fruits ripen and possess high oil, oleic acid and karanjin contents [13]. The purpose of the present study was to provide histological, histochemical and ultrastructural evidence for identifying the exact harvesting period when high reserve accumulation and oil content coincides with the physiological maturity of pongamia seed.…”

De novo sequencing and characterization of seed transcriptome of the tree legume Millettia pinnata for gene discovery and SSR marker development

“…First, the Pongamia trees are capable of producing high yield of seeds with high contents of non-edible oil, which can be readily extracted and converted into biodiesel by transesterification (Karmee and Chadha 2005;Naik et al 2008). Second, the Pongamia seed oil possesses a high proportion of monounsaturated oleic acid and a relatively low amounts of saturated and polyunsaturated fatty acids (Bala et al 2011;Pavithra et al 2012), which may endow the biodiesel products with lower cloud and pour points. Third, being a tree legume, the Pongamia can undergo biological nitrogen fixation and thus reduce the application of nitrogen fertilizers, which may in turn mitigate the deleterious environmental impacts of greenhouse gas emissions or water pollution (Jensen et al 2012;Biswas and Gresshoff 2014;Gresshoff et al 2015).…”