COMPOSITION AND MOLECULAR-SPECIES OF CERAMIDE AND CEREBROSIDE IN SCARLET RUNNER BEANS (PHASEOLUS-COCCINEUS L) AND KIDNEY BEANS (PHASEOLUS-VULGARIS L)

Ceramide and cerebroside were isolated from scarlet runner bean (Phaseolus coccineus L.) and kidney bean (Phaseolus vulgaris L.), and their components and principal molecular species were studied. In the ceramide of the two beans, three types of normal, 2-hydroxy, and 2,3-dihydroxy fatty acids were observed and showed a ratio of about 25:74:1. The major component of the fatty acid was 2-hydroxylignoceric acid, while the major component in the sphingoid was 4-hydroxy-trans-8-sphingenine. In cerebroside of the two beans, normal and 2-hydroxy fatty acids were observed, the latter showing more than about 90 %. The major fatty acid of cerebroside was 2-hydroxypalmitic acid, while the major sphingoids were trans-4,trans-8-sphingadienine and trans-4,cis-8-sphingadienine. The sugars of both cerebrosides were almost glucose. From GC-MS and reversed-phase HPLC data, the major ceramide species in the two beans was found to be N-2'-hydroxylignoceroyl-4-hydroxy-trans-8-sphingenine, and the major cerebroside was found to be 1-O-beta-glucosyl-N-(2'-hydroxypalmitoyl)-trans-4,trans-8-sphingadienine. The major ceramide residues in the cerebroside from the two Phaseolus beans were similar to those of soybean and Adzuki bean but different from that of pea bean, which were mainly N-2'-hydroxypalmitoyl-trans-8-sphingenine residues.