Isolation and identification of chemical substances with antimicrobial activity fromstrongylocentrotus nudus shell

To investigate the inhibitory staphylococcus aureus activity fromstrongylocentrotus nudus shell and isolate and identify the chemical substances.And according to physicochemical properties,spectral analysis and documentation control method,the structure of the isolated compounds were identified.The extraction was obtained with 75% ethanol fromstrongylocentrotus nudus shell,then was extracted with petroleum ether,ethyl acetate and n-butyl alcohol,and they were evaporated to gain all parts of extracts.Inhibitory activity of staphylococcus aureus for the screening of bioactive constituents fromstrongylocentrotus nudus shell was used.Further,the compounds were purified by thin layer chromatography,silica gel column chromatography,semi-preparative thin layer chromatography and recrystallization etc.It showed that ethanol extracts,petroleum ether extracts and nbutyl alcohol extracts had inhibitory activity of staphylococcus aureus.Petroleum ether extracts used silica gel column chromatography and recrystallization repeatly to give compound HDB,was identified as palmitic acid.n-butyl alcoholl extracts through silica gel column chromatography,semi-preparative thin layer chromatography,and recrystallization to give compound HDA,which was identified as(3β)-cholest-5-en-3-ol.