STEROLS OF 14 SPECIES OF MARINE DIATOMS (BACILLARIOPHYTA)1

摘要: The sterol compositions of 14 species marine diatoms were determined by gas chromatography and chromatography-mass spectrometry. A variety profiles found. sterols 24-methylcholesta-5,22E-dien-3β-ol, cholest-5-en-3β-ol, 24-methylcholesta-5,24(28)-dien-3β-ol, previously described as the most common found in diatoms, major only a few species. In light this other recent data, it is clear that these three are not typical constituents many diatom Most centric examined had 24-methylcholesta-5,24(28)-dien-3β-ol 24-methylcholest-5-en-3β-ol two their sterols. exception was Rhizosolenia setigera, which possessed cholesta-5,24-dien-3β-ol its single sterol. contrast to species, pennate did have any particular Minor levels ofΔ7-sterols, rarely large amounts four C29sterols species; seven contained 24-ethylcholest-5-en-3β-ol 24-ethylcholesta-5,22E-dien-3β-ol, reinforcing previous suggestions C29 restricted higher plants macroalgae. 24-Ethylcholesta-5,22E-dien-3β-ol may prove be useful for taxonomy genus Amphora order Thalassiophysales. Fragilaria pinnata uncommon algal 23,24-dimethylcholesta-5,22E-dien-3β-ol. Cholesta-5,24-dien-3β-ol culture Nitzschia closterium. This differed from reports 24-methylcholesta-5,22E-dien-3β-ol N. Two C28 possessing an unusual side chain Thalassi-onema nitzschioides, C28:2 (16%) C28:1 lower abundance (2.5%), 23-methylcholesta-5,22E-dien-3β-ol 23-methyl-5α-cholest-22E-en-3β-ol, respectively. Cylindrotheca fusiformis, T. Skeletonema sp. direct sources cholesterol mariculture feeds due moderate high content