Proximate Composition and Fatty Acid Profile of Pongamia pinnata, a Potential Biodiesel Crop

The chemical characteristics of Pongamia pinnata seeds, focussing on proximate composition and the fatty acid profile of its oil, are presented. The proximate composition of P. pinnata seeds was: 3.8% ash, 9.7% sugar, 7.07% protein, 24% oil, 10.7% free amino acids, and 0.24% free fatty acids. The oil was extracted from seeds by use of different solvents and the highest yield (29%) was obtained by use of n ‐hexane. Monounsaturated and polyunsaturated fatty acids accounted for 63.3 and 22.9%, respectively, of the seed oil. Oleic acid was the major fatty acid but a substantial amount of erucic acid was also detected; this was not reported in previous studies. The level of erucic acid and the presence of toxic flavonoids, for example karanjin, pongapin, and pongaglabrin, render the oil inedible according to WHO recommendations. However, low levels of saturated and polyunsaturated fatty acids with desirable cetane number and iodine value suggest potential for application as a biodiesel fuel.