Sorting out the phytoprostane and phytofuran profile in vegetable oils

Abstract

Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) are prostaglandin-like compounds, contributing to defense signaling and prevention of cellular damage. These plant oxylipins result from autoxidation of α-linolenic acid (ALA) and have been proposed as new bioactive compounds due to their structural analogies with isoprostanes (IsoPs) and prostanoids derived from arachidonic acid in mammals, which have demonstrated diverse biological activities. The present work assesses a wide range of vegetable oils - including extra virgin olive oils (n = 7) and flax, sesame, argan, safflower seed, grapeseed, and palm oils - for their content of PhytoPs and PhytoFs. Flax oil displayed the highest concentrations, being notable the presence of 9-epi-9-D_1t-PhytoP, 9-D_1t-PhytoP, 16-B₁-PhytoP, and 9-L₁-PhytoP (7.54, 28.09, 28.67, and 19.22 μg mL^-1, respectively), which contributed to a total PhytoPs concentration of 119.15 μg mL^-1, and of ent-16-(RS)-9-epi-ST-Δ¹⁴-10-PhytoF (21.46 μg mL^-1). Palm and grapeseed oils appeared as the most appropriate negative controls, given the near absence of PhytoPs and PhytoFs (lower than 0.15 μg mL^-1). These data inform on the chance to develop nutritional trials using flax and grapeseed oils as food matrices that would provide practical information to design further assays intended to determine the actual bioavailability/bioactivity in vivo.

Keywords: Plant oxylipins; Saponification; UHPLC-ESI-QqQ-MS/MS; Vegetable oils; α-Linolenic acid.