Chemical and phytochemical characterizations of argan oil (Argania spinosa L. skeels), olive oil (Olea europaea L. cv. Moroccan picholine), cactus pear (Opuntia megacantha salm-dyck) seed oil and cactus cladode essential oil

Abstract

The chemical and phytochemical characteristics of argan oil (Argania spinosa L. skeels), olive oil (Olea europaea L. cv. Moroccan picholine), cactus pear (Opuntia megacantha salm-dyck) seed oil and cactus cladode essential oil were investigated. The values for acidity varied from 0.28% in argan oil to 1.05% in olive oil. The peroxide values were between 2.26 and 2.84 meq O2/kg oil while the coefficients of specific extinction at 232 and 270 nm ranged from 1.04 to 1.83 and from 0.14 to 0.23, respectively. Regarding fatty acids composition, the essential oil of cactus cladodes (CCEO) contains high concentration of linolenic acid. The cactus pear seed oil has the highest content of linoleic acid, while in argan oil, oleic and linoleic acids were the main fatty acids detected. The total phytosterols content ranged from 203.80 mg/100 g in olive oil to 2131.40 mg/100 g in the CCEO. β-sitosterol was the main phytosterol found in olive oil and cactus pear seed oil. The argan oil is rich in spinasterol and schottenol while the CCEO contains high level of sitostanol. Olive oil encloses 115.80 mg/kg of tocopherols, mainly α-tocopherol form; argan oil has 752.20 mg/kg of tocopherols with dominantly γ-tocopherol, while cactus pear seed oil contains mainly both β-tocopherol and γ-tocopherol. However, α-tocopherol was the only tocopherol detected in CCEO, which interestingly revealed the highest concentration (17.82 mg/kg) of saturated hydrocarbons.