Recherche d’activités biologiques dans les graines de Linum usitatissimum

Abstract

Biological properties, particularly antioxidant and enzymatic activities, are generating increasing interest in health, nutrition, and industry. These biological properties are found in various living organisms, especially in plants. In this study, antioxidant activities (catalase and DPPH radical scavenging) and enzymatic activities (amylase and phytase) were evaluated in flaxseed (Linum usitatissimum) solutions prepared at room temperature and at 50 °C. Catalase activity was detected with an IC50 of 1,1059 mg/mL in the solution prepared at room temperature and 0,7965 mg/mL in the one prepared at 50 °C. For the DPPH scavenging assay, IC50 values of 1,5251 mg/mL and 1,0988 mg/mL were found for the two solutions, respectively.Regarding enzymatic activity, the solutions showed amylase and phytase activities depending on the preparation temperature. Amylase activity reached a starch-degrading capacity of 9.18 μM/mg at room temperature and 25,76 μM/mg at 50 °C, with optimal pH values of 9 and 5, respectively. Optimal temperatures were 50 °C for the room temperature solution and 20, 25 and 40 °C for the solution prepared at 50 °C. These amylases demonstrated good thermal stability and stability in acidic, alkaline, and saline environments.In contrast, phytase activity (Pi release) was higher in the room temperature solution (0,59 mM/mg) than in the one prepared at 50 °C (0,31 mM/mg). Their optimal pH values were 5 and 7, and optimal temperatures were 30 °C and 50 °C, respectively. Unlike amylases, phytases were less stable under thermal and acidic conditions, but moderately stable in alkaline and saline environments.