Physicochemical Analysis and Characterization of the Lipid Fraction of the Tubers of Cyperus esculentus L. var. Sativus from Côte d’Ivoire

Abstract

Aims: this work consists in determining the physical, physico-chemical parameters, the composition in fatty acids and unsaponifiables of the oil of tuber of Cyperus esculentus of Côte d'Ivoire. Methodology: After extraction of the fat by the Soxhlet method with hexane, the physico-chemical parameters were determined by colorimetric assay. The analysis of the fatty acid and unsaponifiable acid composition was carried out by GC-MS. Results: The fat content ranged from 23.64 to 27.66%, those of fatty and unsaponifiable acids were from 90.41 to 95.20% and 1.59 to 1.60%, respectively. As for the values of the acid, peroxide, saponification, iodine, ester, refraction and density indices, they varied respectively from 2.81 to 10.95 mg KOH/g, 1 to 2 meq of O2/Kg oil, 198.72 to 216.78 mg KOH/g, 54.64 to 73.86 g I2/100g oil, 193.11 to 205.83 mg KOH/g, 1.453 to 1.461, and 0.76 to 0.83. In the fatty acid compositionof oils, the predominance of unsaturated fatty acids (70.7-92.14%) was revealed, mainly oleic acid prevails (51.04-82.83%). Additionally, petroselinic (0.23-10.15%,) and 2,6-di-O-palmitoyl-L- ascorbic (8.58-8.84%) acids known for their medicinal properties (anti-inflammatory,  antimicrobial, antioxidants), were first discovered in the oil of Cyperus esculentus. As for the unsaponifiables, they are mainly dominated by phytosterols (22.30-44.03%) and hydrocarbons (27.70-50.8%). Conclusion: These results suggest that oil from Cyperus esculentus tubers from Côte d'Ivoire can be used as an excellent source of edible and medicinal oil.