Exploring the lipidome, nutraceutical profile, anti-oxidant activity and physico-chemical properties of fixed oil derived from fenugreek (Trigonella foenum-graecum L.) seed fractions: a comparative analysis

Selective extraction is an improved method applied to fenugreek seeds to isolate specific bioactive compounds from different seed fractions. This process leads to the recovery of two fixed oils (FO) from husk (HK) and cotyledon (CT) as by-products of the defatting process. The main objective of this study is to investigate and compare the properties obtained from these fractions FO. A comprehensive analysis of the extracted FO was performed, including lipid class distribution, fatty acid analysis, molecular species of triacylglycerols, nutraceutical profile (sterol and tocopherol content), antioxidant activity (polyphenol content) and physicochemical properties. The percentage oil yield of the husk and cotyledon fractions was 2.625 ± 0.2% and 11.6 ± 0.69%, respectively. In addition, nutrient profiling identified β-sitosterol, 1340.31 ± 1.01 and 1670.28 ± 1.22 and α-tocopherol, 0.17 and 0.13 mg/100 g in HK and CT, respectively. Fatty acid analysis revealed a higher proportion of linoleic acid (50.17 µmol %) in HK FO and α-linolenic acid (15.28 µmol %) in CT FO as major fatty acids. The Husk FO exhibited significant antioxidant activity due to its high polyphenol content. Other parameters related to the physical and chemical properties determine the quality, stability and characteristics of the fixed oils from both fractions. The results provide valuable insights into the specific properties of FO obtained from these fractions and shed light on differences in the composition of bioactive compounds such as sterols, tocopherols and fatty acids. This research contributes to the understanding of the constituents of fenugreek seeds and their potential applications in the food and pharmaceutical industries.