Analysis of Volatile Compounds in Algal Bloom Water by Gas Chromatography-Mass Spectrometry and Sniffering
Volatile constituents of algal bloom water were investigated by headspace solid phase microextraction(HS-SPME) coupled with gas chromatography-mass spectrometry(GC-MS).The compounds were quantified by normalization method based on chromatographic peak areas.HS-SPME parameters including different SPME fibers,extraction temperature and time were optimized.In our case,carboxen/polydimethyl-siloxane(CAR/PDMS) fiber was finally used for the extraction at 45 ℃ for 25 min.Aliquot of 82 volatile compounds were identified.The predominant components were butyric acid,isopentanoic acid,acetic acid,dimethyltrisulfide,n-hexanoic acid,o-cresol,propanoic acid,2,3-dithiobutane,pentanoic acid,beta cyclocitral,methyl thiobutyrate,3-methylindole,isopentyl alcohol,methanethiol,1-butanol etc.The GC-MS/GC-sniffering method was employed to perform the identification of the off-flavor compounds.18 kinds of smelly compounds were contained in algal bloom,in which dimethyltrisulfide,2,3-dithiobutane,and beta cyclocitral were significantly increased in the later period of algal blooms outbreak.