Abstract
Carrot-root slices and gratings will effectively incorporate[2-14c]acetate and DL-[2-14c]mevaIonate into [beta]-carotene. Mevalonate is more efficiently incorporated than acetate. 14CO2 ls not incorporated into [beta]-carotene by these preparations. A cell-free system has been obtained from carrot roots which incorporates [2-14C]acetate and DL-[2-14c]mevalonate into [beta]-carotene. The other components of the unsaponifiable matter (mainly sterols) and also labelled.