HPLC-UV and HPLC-positive-ESI-MS analysis of the diterpenoid fraction fromcaper spurge (Euphorbia lathyris) seed oil

Gaper spurge (Euphorbia lathyris L,) seed oil contains a series of diterpen oids known as Euphorbia factors, or L-factors, L1-L9, They are esters of se veral polyols (lathyrol, epoxylathyrol, hydroxylathyrol and ingenol) and ac count for about 3-5% of the oil. The percentage of ingenol-based L-factors is very tow, less than 5% of the diterpenoid fraction, but some of them (fa ctors L5 and L6) are responsible for the irritant and co-carcinogenic activ ities of the oil. This paper reports an HPLC-UV and HPLC-positive-ESI-MS an alysis of the diterpenoid fraction of caper spurge seed oil before and afte r selective hydrolysis of ingenol-based L-factors, Separation of lathyrane polyols and esters, and ingenol and its esters was achieved using a chromat ographic system consisting of a Cls stationary phase and acetonitrile:water as mobile phase. A new macrocyclic constituent, the deoxy Euphorbia factor L1, was identified in the oil. Copyright (C) 2001 John Wiley & Sons, Ltd.