Sphingolipids in immature and mature soybeans

Ceramides and cerebrosides were isolated from immature and mature soybeans, and structures of the constituents were investigated. As component fatty acids, normal, 2‐hydroxy and 2,3‐dihydroxy acids were found in ceramides, whereas only normal and 2‐hydroxy acids were identified in cerebrosides. The principal fatty acid component was 2‐hydroxylignoceric acid in ceramides, and 2‐hydroxypalmitic acid in cerebrosides. Sphingoids in ceramides consisted mainly of trihydroxy bases, with 4‐hydroxy‐trans‐8‐sphingenine being predominant. In contrast, cerebrosides contained mainly dihydroxy bases, the principal constituent beingtrans‐4,trans‐8‐sphingadienine. The only sugar in cerebrosides was glucose. The constituents of the two sphingolipids were similar to each other in immature and mature seeds. Possible metabolic relations of plant sphingolipids, based on composition, are discussed.