Comparative Analysis of Phenolic Contents and In vitro Antioxidant Activity of Argania spinosa (L.) Skeels Sub-fractions Pulp from two Algerian Regions

Argania spinosa L. (Argan tree), also known as “iron tree," is a woody species belonging to the Sapotaceae family and is endemic in North-West Africa. In Algeria, it is found as wild in different regions (Tindouf and Stidia), where they are characterized by a great floristic diversity and it is used by the local populations for therapeutic purposes. The fractionation of the Argan pulp fruit allowed to obtain: hydromethanol (HMTE), ethyle acetate (EATE) and butanol extracts (BuTE) from Tindouf and hydromethanol (HMSE), ethyle acetate (EASE) and butanol extracts (BuSE) from Stidia regions, respectively. The objective of this study is to evaluate the total phenolic, flavonoids and condensed tannins contents using spectrophotometric assays. Qualitative analyses were performed. Furthermore, in vitro antioxidant activity using DPPH radical scavenging activity was evaluated. From the qualitative phytochemical screening, the results revealed the presence of alkaloids, polyphenols, free quinone, anthraquinones, terpenoids, tannins and coumarins in the extracts of A. spinosa L. from the two regions. In quantitative analysis, the results revealed that HMSE presented a high amount of total phenolic and condensed tannins contents with values of 172.55 ± 1.46 μg gallic acid equivalent and 31.04 ± 0.75 μg catechin equivalent/mg dry extract, respectively. This extract show an essential effect toward DPPH-scavenging assay with an IC₅₀ of 05.80 ± 0.00 μg/mL, followed by HMTE with an IC₅₀ of 08.40 ± 0.00 μg/mL, respectively. In conclusion, the Argania spinosa L. fruit provides effective natural antioxidants for the patient, as well as alternatives for natural antioxidants.