Effect of Heating Temperatures on the Physicochemical Parameters and Antihyperglycemic Activity of Argan seeds oil In vitro and In vivo

Argania spinosa seed oil is traditionally used in Morocco for diabetes management due to its antihyperglycemic properties. Although, the optimal roasting temperature for seed preparation to maximize oil quality while preserving bioactive compounds remains unexplored. This study aimed to identify the best roasting temperature that maintains the oil’s antihyperglycemic efficacy and physicochemical integrity. Argan seeds were roasted at temperatures ranging from 0 to 150 °C, and the resulting oils were subjected to both in vitro and in vivo evaluation. Roasting increased oil yield and polyphenol content, which peaked at 8.46 ± 0.02 µg GA/mg at 100 °C; above this temperature, polyphenol levels declined. Temperatures above 100 °C adversely affected peroxide value, free acidity, α-amylase inhibitory activity, and hemoglobin antiglycation activity. Furthermore, roasting above 75 °C significantly reduced free-radical-scavenging activity and tocopherol content, while roasting above 125 °C impaired antioxidant activity (β-carotene bleaching test), tannin content, and carotenoid levels. Fatty acid and flavonoid contents remained stable across all temperatures. These findings suggest that roasting Argan seeds at approximately 100 °C produces oil of optimal quality with preserving antihyperglycemic properties.