New Insights into Trace Element Accumulation in Kernels of Two Algerian Populations of Argan (Argania spinosa (L.) Skeels): An Endangered Endemic Tree

Abstract

Argan is one of the valuable oilseed trees in the Northwest Africa area, with important ecological and socioeconomic benefits; however, information underlying its elemental status remains absent . The current work was performed for the first time to quantify the mineral status of Argania spinosa kernels collected from two different geographic Algerian regions (Mostaganem and Tindouf). Elemental investigation (As, Br, Ca, Ce, Co, Cr, Fe, K, La, Na, Rb, Sb, Sc, Sm, Th, and Zn) was performed using neutron activation analysis (NAA). Two standard reference materials from the National Research Center for certified reference materials (China), namely, CRM-GBW 07605 (GSV-4 tea leaves), and the National Institute of Standards and Technology (USA), namely, NIST (SRM 1573a, tomato leaves), were used to ensure precision and validation of NAA measurements. A computational calculation of data including principal component analysis (PCA) and Pearson correlation coefficient (r) was applied. The extents of essential elements in Mostaganem kernels were found to be in the order of K (7185 μg g^-1) > Ca (2079 μg g^-1) > Na (205 μg g^-1) > Fe (84.33 μg g^-1) > Zn (73.41 μg g^-1) > Cr (0.66 μg g^-1) > Co (0.035 μg g^-1), whereas the overall order of these elements in Tindouf kernels was K (7206 μg g^-1) > Ca (3725 μg g^-1) > Fe (114.69 μg g^-1) > Zn (67.37 μg g^-1) > Na (56.29 μg g^-1) > Cr (0.54 μg g^-1) > Co (0.11 μg g^-1). PCA results revealed that Tindouf population was highly loaded with Br, Cr, Cu, Mn, Sr, V, and Zn, while Mostaganem population was associated only with Ce and Sm contents. These findings can be useful for making new formulations for cosmetic and culinary usage and contribute to the nutritional database and food safety.

Keywords: Argania spinosa; Cosmetics; Geographic origin, PCA analysis; Kernels.