Separation and isolation of saturated and unsaturated 5-n-alk(en)ylresorcinols from rye bran

Alkylresorcinols (AR) are a class of phenolic lipids which are found in a number of plants and microorganisms and which are associated with various biological activities. In view of the very limited availability of reference compounds, we developed a process for the isolation of AR from rye bran. For this purpose, a crude extract was subjected to deep bed filtration at -80 °C, whereby the crystallized saturated AR were separated from the unsaturated homologues. Highly purified, individual compounds were subsequently isolated by semi-preparative HPLC. In contrast to previously published approaches, the method reported here is relatively easy to perform and allows the recovery of saturated and unsaturated AR of high purity. Furthermore, it is superior to argentation chromatography because it does not necessitate the removal of silver ions for subsequent bioassays.