Separation of Sterols by Reversed Phase and Argentation Thin Layer Chromatography. Their Identification in Snail Bodies

Abstract

Separation of the sterols: cholesterol, cholestanol, β‐sitosterol, stigmasterol, ergosterol, campesterol, desmosterol, and brassicasterol was compared using reversed phase, multimodal, and argentation thin layers. Layers tested include C18, C18W, NH2, CN, diol, C2, C8, and phenyl bonded layers; hydrocarbon impregnated layers; and commercially prepared silica gel layers precoated with 10% silver nitrate. It was determined that C18 layers with acetonitrile–chloroform (40∶35) or petroleum ether–acetonitrile–methanol (2∶4∶4) gave optimal sterol separations. Desmosterol, campesterol, brassicasterol, β‐sitosterol, ergosterol, and cholesterol and/or stigmasterol were identified in the bodies of the snails Biomphalaria glabrata, Helisoma trivolvis, and Pomacea bridgesii.