The Occurrence of Brassicasterol in the Diatoms, Cyclotella nana and Nitzschia closterium

Abstract

Very little information has been reported about the sterol in diatoms. In this paper, the sterol composition of the marine diatoms, Cyclotella nana and Nitzschia closterium was investigated. The sterols from Cyclotella and Nitzschia gave the melting point of 148°C and the molecular weight of 398 (mass spectrum). In gas-liquid chromatography on four different columns, this algal sterols were found to be composed of only one component identified as brassicasterol. Infrared absorption spectra and mass spectra analyses also supported the structure of brassicasterol.