Quantitative and Qualitative Analysis and Evaluation of Antioxidant Activity of Phenolic Compounds Extracted from Apiaceae Family Spices

The aim of the present study is to analyze the phenolic compounds extracted from seeds of four spices belonging to Apiaceae family, namely caraway (Carum carvi), coriander (Coriandrum sativum L.), mystical cumin (Ammodaucus leucotrichus), and cumin (Cuminum cyminum L.). The extraction was carried out using solvents of different polarities (water, ethanol, methanol, and hexane). The antioxidant activity of each studied spice was performed by different methods including total antioxidant capacity (TAC), 2,2'-azino-bis3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 1,1-diphenyl-2 picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and metal ion chelation power (CP). Based on obtained results, a significant difference in the phenolic compounds contents of analyzed seeds was observed. The lowest phenolic compounds level was obtained by the hexane extract for the four studied spices. Besides, the aqueous extract (AE) of conventional cumin showed the highest level of phenolic compounds (16.49 mg Gallic acid equivalents (GAE)/g dry weight (DW)), followed by the AE of caraway (15.9 mg GAE/g DW), then the AE of mystical cumin (15.01 mg GAE/DW), and, at the end, by the AE of coriander (12.89 mg GAE/g DW). This work revealed a well correlation between the antioxidant activities of the studied seed and the type of solvents used for their extraction. The studied spices present a much-diversified molecular weights distribution of the phenolic compounds evaluated by exclusion chromatography on Sephadex G50 gel. The climatological analysis showed also that the production of phenolic compounds was strongly influenced by some environmental factors such as the mean annual rainfall and temperature values registered in the planting zones of the four studied spices in Morocco.