HIBISCUS-SABDARIFFA SEED OIL - REINVESTIGATION

Abstract

Due to controversial reports on the component acids of Hibiscus sabdariffa seed fat and in anticipation of the co-occurrence of cyclopropene and epoxy acids in the seed oils of Malvaceae (especially in the genus Hibiscus)5,6 it was considered worthwhile to re-examine the seed oil of H. sabdariffa. Seed oil of H. sabdariffa (Malvaceae) contains myristic (2.1%), palmitic (35.2%), palmitoleic (2.0%), stearic (3.4%), oleic (34.0%), linoleic (14.6%) and three unusual HBr-reacting fatty acids. These acids are cis-12,13-epoxy-cis-9-octadecenoic (12,13-epoxyoleic), 4.5 %; sterculic, 2.9%; and malvalic, 1.3%. Acetolysis of epoxide in the presence of cyclopropenes was effected by room temperature treatment with acetic acid-10% sulphuric acid. Seed oils of Vernonia anthelmintica and Sterculia foetida were used as reference standards.