Introduction: Okra (Abelmoschus esculentus) is an annual culinary plant of Malvaceae family with high nutritional and medicinal values. This plant is widely cultivated in different regions of Iran as well as the world.

Aims This study investigated the fatty acid composition and antioxidant activity of seed oils extracted from seven okra cultivars, including: White, Sultani, Red, Velvet, Green, Texas, and Fawn. Material and methods: The mature and intact seeds of each cultivar were powdered and their oils were extracted using the modified Folch et al. method. The fatty acid methyl esters were obtained from seed oils using transesterification method. Then, the oils were injected to GC and GC/MS apparatus to detect their fatty acids profile. The DPPH method was applied to detect antioxidant activity of the extracted okra oils. Data was analyzed using SPSS and MVSP software. Results: The seed oils in all cultivars were comprised both saturated and unsaturated fatty acids, while, their total percentages varying among these cultivars. The highest total saturated fatty acid content (42.53%) was observed in the white cultivar, while the lowest (36.41%) was detected in the Sultani cultivar. Palmitic acid was the predominant saturated fatty acid in all the cultivars, with its highest (35.74%) and lowest (30.7%) percentages were found in the white and Texas cultivars, respectively. Stearic acid was the second most abundant saturated fatty acid in all examined oils, ranging from 3.69% (Sultani cultivar) to 4.94% (white cultivar). Some trace amount saturated fatty acids such as heptadecenoic, arachidic, behenic, and lignoceric acids were present in all the cultivars, with lauric acid had a restricted distribution and was only detected in a few cultivars, including: velvet, Texas, and white cultivars. Unsaturated fatty acids constituted 57.33% to 63.33% of the oils composition, with the lowest and highest percentages in white and Sultani cultivars, respectively. Linoleic acid was the primary unsaturated fatty acid in all the cultivars except white cultivar, where oleic acid was detected as predominated unsaturated fatty acid. The highest linoleic acid percentage (11.40%) was detected in red cultivar and the lowest (8.25%) in white cultivar. The amount of oleic acid ranged from 18.20% (red cultivar) to 49.30% (white cultivar). Some trace amount unsaturated fatty acids such as myristoleic, palmitoleic, trans-heptadecenoic, linolenic, gondoic, and erucic acids were present in all the cultivars. Additionally, all the cultivar had eicosadienoic acid in a trace amount, except for white cultivar. Phytochemical analysis using UPGMA dendrogram and PCA analysis divided these cultivars into two main clusters, confirming significant phytochemical diversity. It seems that change in the predominant unsaturated fatty acid, oleic acid in the white cultivar instead of linoleic acid. Additionally, the presence of palmitic acid as the dominant fatty acid in the velvet and white cultivars, were two main reasons for placement of white, green and velvet cultivars far from other cultivars. Antioxidant activity assessed by the DPPH method revealed IC50 values ranging from 689.23 µg/mL in green cultivar to 2551.12 µg/mL in Texas cultivar. Discussion: the seed oil profile of white cultivar is more different from the others. Moreover, the week or trace antioxidant activity was detected for the oils of diverse okra cultivars. These findings highlight the nutritional and industrial potential of okra seed oils. Additionally, the oil profile can strongly influence the antioxidant activity of the oils.