Stearoyl-ACP Delta 9 DesaturaseMight not be the only Factor Affecting Unsaturated Fatty Acids Concentration in Oil Palm (Elaeis Sp.)

Oil palm (Elaeis guineensis) is currently the major oil-producing plant in the world. E. oleifera is another species of oil palm that is not widely cultivated due to lower productivity. Oil extracted from E. guineensis showed a balance ratio of saturated to unsaturated fatty acids level, while oil from E. oleifera showed higher unsaturated fatty acids. Long chain-saturated fatty acids are more harmful to health than unsaturated fatty acids. In this research gene encoding steraoyl-Δ9-acyl carrier protein (ACP) desaturase enzyme (SAD, EC 1.14.19.2) was studied, as this is one of the responsible enzyme for biosynthesis of unsaturated fatty acids. Analysis were conducted on SAD gene and fatty acids content of E. guineensis, E. oleifera represented by Suriname and Brazil origin and the Hybrids (offspring of crossing between E. guineensis and E. oleifera). The result shows that no amino acid variations among SAD gene were found within E. guineensis and Hybrids, whereas two variations were found between E. oleifera. However, the mutations were found not within the core domains that were the polypeptides, substrates, or ions binding site of the enzyme. Concentration of oleic fatty acid (OLA, C18:1) of E. guineensis, E. oleifera and Hybrids showed variation. This variation might be indirectly influenced by other enzymes that acting prior to SAD such as β-ketoacyl ACP synthase (KAS II) enzyme that result in variation of stearic fatty acid (STA, C18:0) accumulation and thus further OLA content.