The latex of Euphorbia lathyris was shown to be capable of producing l
anosterol, as well as cycloartenol, butyrospermol and hopenol B, via t
he enzymatic cyclization of 2,3-oxidosqualene. The conversion of cyclo
artenol to lanosterol could not be demonstrated using the same latex.
The triterpene composition of the latex of Euphorbia lathyris is repor
ted.