The isolation of carotene and sterols from the unsaponifiable matter of cocksfoot

Abstract

32.7 kgm. of dried cocksfoot (Dactylis glomerata) was extracted with light petroleum. After removal of the wax and phosphatide, the extract was partitioned between light petroleum and 92% methanol. The light petroleum solution after saponification with KOH, concentration and dilution with alcohol gave 7 gm. of crude carotene. Re-crystallisation from benzene-methanol gave 4 gm. of pure [beta]-carotene, confirming the results of other workers on the nature of grass carotene. The mother liquors on concentration gave 12.85 gm. sterol M. P. 138-139[degree] (un-corr.) and [[alpha]]D=[long dash]36[degree], consisting of sitosterol with 0.4% of ergosterol identified by isolation of the pinacol M. P. 201[degree] and its acetate M. P. 204[degree] (both uncorr.). The problem of the identification of such compounds is discussed.