CHARACTERIZATION AND COMPARISON OF THE THREE CULTIVARS SEED OIL OF OPUNTIA FICUS - INDICA IN TUNISIA

The Barbary fig is a plant of the arid and semi - arid areas that is able to adapt to poor soils and high temperatures. The cactus has interesting properties that grow and develop the culture promote its byproducts. This study was conducted on three cultivars of Opuntia ficus - indica are those of Zelféne, Sbeïtla and Kairouan. The study was made in order to carry out a description and comparison between cultivars. In terms of recovery methods, extraction and characterization of the oil was made from the seeds. The oil yields vary from 1.35 to 1.9% for Sbeïtla and Kairouan cultivars and reached 2.7% for the cultivar Zelféne. The major fatty acids present in the oil of the seeds are palmitic acid (C16: 0), stearic acid (C18: 0), linoleic acid (C18: 2) and oleic acid (C18: 1 ). However, the most domin ant fatty acid is linoleic acid with 61.79 of contents; 57.19 and 58.92% respectively for Zelféne, Sbeïtla and Kairouan. As for the sterol composition, siosterol Beta is the major component of this oil whose content varies from 67.14% for the cultivar Sbeï tla and 81.18% for that of Zelféne. Seed of oil is also r ich in vitamins (tocopherols) which γ - tocopherol is the largest reaching 57.98 mg / 100 g of oil. Keywords: