Determination of LC-MS/MS phenolic profile, antioxidant and α-glucosidase enzyme inhibition activities of Linum mucronatum Bertol. subsp. armenum (Bordz.) P.H.Davis

Plants include compounds having high antioxidant activity such as flavonoids, phenolics, and carotenoids. Antioxidant defense mechanisms play an important role in the prevention and treatment of oxidative stress diseases in humans. In the present study, the flower and leaf parts of Linum mucronatum subsp. armenum were extracted in five different solvents. The antioxidant activities of the extracts were determine using six antioxidant activity determination assays (Iron (III) reducing/antioxidant power (FRAP), DPPH radical scavenging activity, copper (II) reducing antioxidant activity (CUPRAC), ABTS radical scavenging capacity, total flavonoid content and total phenolic content). While, the methanol extract showed the highest activity for the flower part, ethanol extracts of leaf part showed the highest antioxidant activity in the DPPH, FRAP and CUPRAC tests. The highest activity values in both flower and leaf parts was measured in acetone extract with SC50=0.287 mg/mL and (SC50=0.163 mg/mL in ABTS test, respectively. Lowest activity values of solvent extracts were measured in hexane extracts in all tests. Phenolic compounds of the plant were identified using LC-MS/MS. These phenolics are kaempferol, vanillin, protecatechuic acid, caffeic acid, p-coumaric acid, p-OH benzoic acid, salicylic acid, quercetin and rutin. The leaf and flower parts have α-glucosidase enzyme inhibitor effect. It was determined that the leaf part of the plant (IC50=4.533 mg/mL) have higher enzyme inhibition than in the flower (IC50=6.096 mg/mL). As a result, it was determined that the plant showed the biological activity. The results will contribute to the studies on the biological activity of the other plant.