## 3 Results and Discussion
### Fatty Acid Methyl Esters (FAME) Content  
The fatty acid composition of the analysed oils is presented in Table 2. The major fatty acids in flax seed oil were \(\alpha\)-linolenic (C18:3n3c), oleic (C18:1n9c), and linoleic (C18:2n6c) acids. Minor ones were stearic (C 18:0), palmitic (C 16:0), and elaidic (C18:1n9t) acids. Similar results were reported by [PERSON] and [PERSON] [34] in a study on 84 varieties (\(\alpha\)-linolenic acid 48.4-58.9%, linoleic acid 10.3-17.3%, palmitic acid 4.2-6.6%, stearic acid 2.6-5.1%). Supplementing the diet with flax seeds and the related oil, which contains significant levels of \(\alpha\)-linolenic acid and lower levels of linoleic acid, enables the body to receive the required ratio of diunsaturated (n-6) to triunsaturated fatty acids (n-3). Only a few food products contain \(\alpha\)-linolenic acid, which must be supplemented in the diet to safeguard health. The ingestion of 2.2 g of _alpha_-linolenic acid per day from flax seed oil enhanced verbal fluency in healthy people without cognitive impairments, despite an age-related reduction in cognitive function [35]. Major fatty acids in poppy seed oil (Table 2) were linoleic (C18:2n6c), oleic (C18:1n9c), and palmitic (C 16:0) acids. Minor fatty acids were stearic (C 18:0), \(\alpha\)-linolenic (C18:3n3c), and elaidic (C18:1n9t) acids. In a study by [PERSON] et al. [29] linoleic acid (71%), followed by oleic (15%) and palmitic (9%) acids, were found to be dominant in four Turkish poppy seed varieties. These findings are comparable with our results. Due to its high linoleic and low linolenic acid content, poppy seeds are a suitable crop for the food industry. Due to its instability and changes brought on by auto-oxidation, high levels of linolenic acid are problematic in food production. [PERSON] and [PERSON] [36] analysed expeller-pressed poppy seed oils from Turkey and reported a high level of linoleic acid (70%), followed by oleic acid (15%) and palmitic acid (8%). These authors also confirmed that poppy seed oil is very rich in antioxidants, especially apigenin, syringic acid, luteolin, \(p\)-coumaric acid, quercetin, and ferulic and sinapic acids. Linoleic (C18:2n6c), oleic (C18:1n9c), and palmitic (C 16:0) acids were dominant in milk thistle oil (Table 2). Stearic (C 18:0), \(\alpha\)-linolenic (C18:3n3c), and elaidic (C18:1n9t) acids were also present. This oil was also found to contain arachidonic (C 20:0), eicosenic (C20:1n9c), and behenic (C22:0) acids, which were absent in the other samples. Our results are comparable with the results of [PERSON] and [PERSON] [11], who analysed the fatty acid profiles of oil obtained in Iran from different milk thistle varieties. The average amounts of acids in their study were 51% linoleic, 23% oleic, 8% palmitic, 6% stearic, 1% arabic, 2.3% behenic, and 0.9% eicosenic acid. Linoleic acid (52%), \(\beta\)-sitosterol (68 mg/100 g oil), and \(\gamma\)-tocopherol (54 mg/kg oil) were determined as the dominant  
Figure 1: Results of antioxidant activity of analysed oils. (FO—flax seed oil; PO—poppy seed oil; MTO—milk thistle seed oil; GO—grape seed oil; WO—walnut oil; TEAC—Trolox equivalent antioxidant activity). components in cold-pressed milk thistle oil in a study by [PERSON] et al. [24]. In grape seed oil (Table 2), linoleic acid (C18:2n6c) was the main fatty acid. It was followed by oleic (C18:1n9c) and palmitic (C 16:0) acids. Minor fatty acids were stearic (C 18:0), \(\alpha\)-linolenic (C18:3n3c), and elaidic (C18:1n9t). Only in this oil was linoelaidic acid detected. A similar tendency was observed in a study by [PERSON] et al. [37], who reported linoleic (72%) and oleic (13%) acids dominating the composition of grape seed oil processed by chloroform. In a study by [PERSON] (2004), individuals who consumed up to 45 g of grape seed oil daily showed decreased LDL cholesterol and increased HDL cholesterol, respectively. In walnuts, the dominant fatty acid was linoleic acid (C18:2n6c), followed by oleic (C18:1n9c) and \(\alpha\)-linolenic (C18:3n3c) acids.