Phenolic Compounds, Fatty Acid Composition, and Antioxidant Activities of Some Flaxseed (Linum usitatissimum L.) Varieties: A Comprehensive Analysis

Flaxseed, also known as flax or linseed (Linum usitatissimum L.), is one of the oldest crops. It is used for oil and fiber production. The species displays a broad range of biological activities due to its chemical compounds. It has a widespread geographical distribution, and a large number of its varieties have been evaluated for their biological efficacy and nutritional value. This study investigates fifteen varieties of the species, some of which are examined for the first time. In this regard, a series of chemical composition analyses and antioxidant assays were carried out. Accordingly, total phenolic content ranged between 613.6 (Michael) and 3164.6 (Atalanta) mg GAE/g, whilst total flavonoid content varied from 176.25 (BonnyDoon) to 689.20 (Mcduff) mg QE/g. Regarding the radical scavenging assays, the values obtained were significantly higher than those of the standard antioxidant (ascorbic acid). Furthermore, the extracts exhibited chelating activity for ferrous ions and a cupric reducing capacity that was comparable to that of the standard. The oil content values of the varieties ranged from 0.82 g/100 g (Michael) to 2.14 g/100 g (McGregor). The percentage of α-linolenic acid varied between 39.21% (McGregor) and 54.13% (Nareum).