Fatty acid compositions and antioxidant activities of Ranunculus isthmicus subsp. tenuifolius and Ranunculus rumelicus

Abstract

The content of fatty acids in plants and especially the ratio of unsaturated to saturated fatty acids is very important. Phenolic compounds and flavonoids with antioxidant properties are useful in scavenging harmful radicals. In this study, fatty acid compositions and antioxidant activities of the aerial parts of Ranunculus isthmicus subsp. tenuifolius (syn. Xiphocoma tenuifolia) and Ranunculus rumelicus from Turkey were evaluated. Fatty acid methyl esters (FAMEs) of the oil extracts of two Ranunculus species were prepared. The fatty acid compositions of plants were investigated by gas chromatography (GC). Unsaturated fatty acids were detected in higher amounts than saturated fatty acids. The primary unsaturated fatty acids of the R. isthmicus subsp. tenuifolius oil were linoleic acid (38.42%), oleic acid (18.24%), palmitoleic acid (8.96%), and palmitic acid (8.12%) were determined fatty acid. Linoleic acid (24.09%), palmitoleic acid (16.25%) and palmitic acid (10.32%) were found in R. rumelicus oil as the major fatty acids. The antioxidant activities of methanol extracts of two plants were evaluated by DPPH•, ABTS•+, and CUPRAC assays. The extracts' total phenolics and flavonoid contents were determined by Folin-Ciocalteu and aluminium chloride methods, respectively. The methanolic extract of Ranunculus isthmicus subsp. tenuifolius demonstrated the higher antioxidant activity compared to R. rumelicus. The extracted oil from both Ranunculus species is a good source of essential fatty acids, especially linoleic acid. According to the antioxidant activity findings, it was determined that the extracts showed a significant correlation with the total phenolic and flavonoid contents.