Evaluation of yield and fatty acid composition of seed oils from cactus varieties resistant to Dactylopius opuntiae (Hemiptera: Dactylopiidae) in Morocco

Abstract

The Cactus Opuntia spp. plant is important to Morocco's arid and semi-arid regions. The edible and cosmetic oil from prickly pear fruit seeds is very prized. Since Dactylopius Opuntiae first appeared in Morocco in 2014, hundreds of hectares of cactus have been devastated, causing environmental and socio-economic costs. Eight D. Opuntiae resistant varieties were selected, multiplied and transplanted throughout Morocco, as part of the government's nationwide cactus rehabilitation program. This research evaluated the production and fatty acid composition of the seed oil of these varieties. Oil extraction was carried out with the Soxhlet method using hexane and by mechanical screw press. The crude seed oil content obtained by hexane extraction ranged from 9.54% to 16.44% (w/w). Mechanical screw extraction recovered half the seeds' oil. The fatty acid profiles showed that the oils were highly unsaturated; UFA fraction represented 76.31 to 82.63% of total FA and UFA/SFA ratio of 3.48 to 5.36. Linoleic acid was the dominant and represented 61.50% to 68.35% of total FA. These results highlight the importance of cochineal-resistant cactus varieties as oil sources and alternatives to those destroyed and still threatened by the harmful scale pest that appeared in more than 20 countries.