Sphingoid base composition of monoglucosylceramide in Brassicaceae

The sphingoid base composition of monoglucosyolceramide was examined in lea ves and roots of six species of the family Brassicaceae. The major componen ts of the nine sphingoid bases we detected were 4-hydroxy-8-sphingenine [i. e. t18:1(8E) and (8Z)] and 8-sphingenine, in both leaves and roots. The com position was unique because the relative proportions of 8-E/Z isomers in 4- hydroxy-8-sphingenine and in 8-sphingenine were different. So far, only chi lling-resistant plants have been found to contain more t18:I (8Z) component s than t18:1(8E) [Imai et at. (1997) Biosci Biotechnol Biochem 61:351-353], Species of the family Brassicaceae can now be added to this list.