Physicochemical properties, phenolic acids and volatile compounds of oil extracted from dry alhydwan (Boerhavia elegana Choisy) seeds

Abstract

In this study, the chemical composition, physicochemical properties, phenolic acids and volatile compounds of alhydwan (Boerhavia elegana Choisy) seed oil were evaluated. The crude oil content was 11.49%, ash 6.88%, moisture 6.12%, protein content 14.60%, total carbohydrate 24.77% and fiber 36.13%. The oil contain a high quantity of unsaturated fatty acids (74.63 mg·100 g -1) with oleic (C18:1) (57.77%), palmitic (C16:0) (18.65%) and linoleic (C18:2) (12.88%) acids as the most abundant. The relative density was 0.88 and the iodine value 105.59. The color analysis showed a value of 28.33 Y+1.43 R. The oil also had a high relative oxidative stability. The tocol composition showed that α-tocotrienol, γ-tocopherol and γ-tocotrienol were in a higher concentration than the rest. Seven phenolic acids (caffeic, vanillic, galic, p-coumaric, ascorbic, cinnamic and ferulic) were detected, with ascorbic acid as the predominant one (5.44 mg·100 g -1). In relation to the volatile composition, 48 compounds were found with Z-10-Pentadecen-1-ol (56.73%); Hexadecenoic acid, Z-11-(18.52%); 9,12-Octadecadienoic acid (Z,Z)-(3.93%) and 9,12-Octadecadienoic acid (Z,Z)-, 2-hydroxy-1-(hydroxymethyl) ethyl ester (3.04%) as the most abundant. These findings demonstrated the potential of alhydwan seeds to be used as a good source of quality edible oil.