Geographic impact on Opuntia ficus-indica seeds: oil and phenolic compound extraction and characterization

Abstract

In this study, we studied the Moroccan Opuntia Ficus indica (OFI) seeds of two different regions the west of Morocco – Kenitra (OFIK) and the east of Morocco – Nador (OFIN), we started by the determination of the moisture and elemental content of the seeds using inductively coupled plasma atomic emission spectrometry ICP-AES, following the oil extraction using Soxhlet method we obtained a yield of extraction ≈ 8%, that we determine its quality using different characterization methods that all show that our extracted oil is in a good quality, also we used Gas chromatography–mass spectrometry (GC–MS) analysis for the fatty acid methyl ester (FAMEs) after the oil methylation, the results show the that the oils contains an interesting content of linoleic acid with 76.4 and 79.11% and oleic acid 11.77and 8.83% also palmitic acid 7.78 and 7.75%, and stearic acid 3.45 and 3.68% . Also, we analyzed the oils with Fourier transform infrared spectrometer FTIR and for the remained seeds we used scanning electron microscope with Energy Dispersive X-Ray (SEM-EDX). For the defatted seeds we extracted the phenolic compounds that we determine their total polyphenols content, total flavonoids, condensed tannins, total monomeric anthocyanins and sugars. Also, we studied the oil and different fractions antioxidant activities using free radical DPPH scavenging that shows a remarkable inhibition up to 87%, and for the different fraction the Ethyl Acetate fraction EAF has an “EC50” =48.001 μg/mL compared to ascorbic acid =16.8864 μg/mL. • The geographic impact on the Opuntia Ficus Indica (OFI) seeds can be noticed in the amount of each fatty acid and the phenolic compounds. • The Moroccan Opuntia Ficus indica (OFI) seeds oil is rich in fatty acids such as linoleic, oleic, and palmitic acid. • The OFI seeds have an interesting number of phenolic compounds, also a high antioxidant activity. • The OFI seeds oil were characterized with FTIR, and the seeds residue with SEM-EDX for a better closeup on the morphology.