Enrichment of high‐purity nervonic acid ethyl ester from Acer truncatumBunge seed oil by combination method of urea inclusion and molecular distillation

Abstract Acer truncatum Bunge is a type of maple that is unique to China. Its fruit setting rate and seed oil content are both high. The oil is mainly composed of C16–C24 fatty acids and contains 5%–7% nervonic acid (NA). NA and its derivatives can delay ageing and prevent and treat disorders such as senile dementia and Alzheimer's disease. The content of NA ethyl ester prepared by the seed oil of A. truncatum Bunge is 5.84%. We report a new process for the enrichment of NA ethyl ester by urea inclusion (UI) and molecular distillation (MD), with the aim of obtaining highly pure NA ethyl ester. First, based on the difference in fatty acid ethyl ester saturation and carbon chain length, unwanted compounds such as oleic acid ethyl ester, linoleic acid ethyl ester, and sterol were removed by one‐stage UI, the content of NA ethyl ester was increased to 18.69%. The oil in the UI compound was used as a feed, and differences in the mean molecular free paths between the components were exploited to separate the C16–C20 fatty acid ethyl esters (FAEEs) by two‐stage MD. The total content of C16–C20 FAEEs decreased to 3.69% and the purity of NA ethyl ester increased to 47.47%. A new purification process of UI‐MD‐UI was established and NA ethyl ester could be purified to 91.8%. The combination of MD and UI has an important reference value for the industrialization of producing high‐purity NA ethyl ester.