Biosynthesis of α-elostearic Acid in the Seed of Momordica Charantia L.

Momordica charantia L. is a plant belonging to Cucurbitaceae family. Currently it is cultivated throughout the word mostly for the immature fruits. Its seeds oil contains a large amount of α-eleostearic acid (αESA) , an isoform of α-linolenic acid with conjugated double bound. Oils with conjugated fatty acids are valuable both for industrial and nutraceutical application. After cloning the fatty acid conjugases (FADX), several attempts have been made to modify oilseed crops towards production of such fatty acids. The obtained transgenic plants produced, however, a much lower amount of conjugated fatty acids than FADX original plants. It has been postulated that this could be connected with the problem in the transfer of such fatty acids from the place of its synthesis – phosphatidylcholine (PC) – to the place of their storage – triacylglycerol (TAG) in the transgenic plants. In this study we have characterised the biosynthesis of α-eleostearic acid both in vivo in developing seeds of M. charantia and in vitro in experiments with microsomal fractions prepared from developing seeds of this plant. We observed significant differences in transfer of αESA from the place of its biosynthesis to TAG in these two system. In vivo αESA was very efficiently transferred while in vitro synthesised αESA remained mostly in PC.