RESUMO
Objective:According to the GB/T 15000.3-2008， to develop a fucosterol certified reference material based on the project approved by Standardization Administration. Method:Fucosterol was isolated from <italic>Laminaria japonica</italic> dried thallus via 95% ethanol extraction， vacuum concentration， repeated column chromatography separation， recrystallization in petroleum ether-ethyl acetate， and residual solvent removal. Its chemical structure was identified by elemental analysis （EA）， infrared spectrum （IR）， mass spectrometry （MS）， nuclear magnetic resonance （NMR） and X-ray diffraction （XRD）. Its homogeneity， stability， and cooperative certification conducted by 8 laboratories were carried out by high performance liquid chromatography with evaporative light scattering detector. Result:For the fucosterol reference material， the certified value of purity was 99.54% with expanded uncertainty of 0.16% in confidence interval of 95%， the stability was good within 24 months storage period at 2-4 ℃， which met the technical requirements of reference material and passed the acceptance organized by Standardization Administration. Conclusion:The national standard materials of fucosterol has been successfully developed， which can be used for the determination of this component， the evaluation of detection methods， and the detection and quality control of related products.
RESUMO
Four compounds have been isolated from Sargassum fusiforme(HaTv. ) Setch. collected in the south Zhejiang province of China. Among these compounds the structures of three have been deduced as mannitol, fucosterol and saringosterol on the basis of chemical and IR,NMR,MS spectral data.