Composition of Fatty Acids, Total Sterols and Total Polyphenol Content of the Oils of Six Oilseeds in Côte d'Ivoire

Aims: This study aims to determine the fatty acid, sterol and total polyphenol composition of Ricinodendron heudelotii, Terminalia catappa, Moringa oleifera, Cyperus esculentus, Sesamum indicum and Coula edulis oils.

Study Design: Plant material consisting of almonds of Ricinodendron. heudelotii, Terminalia catappa, Moringa oleifera, rhizomes of, Cyperus esculentus, seeds of Sesamum indicum and hazelnuts of Coula edulis were collected in different producing areas of Côte d'Ivoire in 2017.

Place and Duration of Study: This study was conducted between November 2017 and June 2018 at the Laboratory of Industrial Processes, Synthesis, Environment and New Energies, National Polytechnic Institute Félix Houphouët-Boigny, Côte d'Ivoire.

Methodology: The extraction of oil from the oil-bearing organs of different plants was carried out by maceration of the crushed parts of these organs in hexane at a crushed/solvent ratio of 1:10 (grams/volume) for 6 hours at cold temperature. These oils were analyzed by gas chromatography for the determination of fatty acid profile, then by gas chromatography coupled with a mass spectrometer for the determination of sterols and Ultraviolet-visible spectrophotometer for the quantification of polyphenols.

Results: The results show a fatty acid composition of the different oils dominated by four fatty acids: oleic (18.89 - 93.93%), linoleic (1.03 - 43.2%), palmitic (2.65 - 35.6%) and stearic (1.09 - 11.66%). We also note average unsaponifiable matter (0.5 - 1.71%) and sterols dominated by sitosterol, stigmasterol and campesterol. Concerning polyphenols, the values obtained range from 52.09 to 863.67 µg gallic acid equivalent/g oil.

Conclusion: The presence of sterols, phenolic compounds and unsaturated fatty acids in interesting proportions show that these oils are important sources of edible oils beneficial to human health.