Seasonal variations of bromophenols in brown algae (Padina arborescens, Sargassum siliquastrum, and Lobophora variegata) collected in Hong Kong

Distributions and seasonal variations of the key seafood flavor compounds including 2-bromophenol, 4-bromophenol, 2,4-dibromophenol, 2,6-dibromophenol, and 2,4,6-tribromophenol in three species of brown algae (Padina arborescens, Sargassum siliquastrum, and Lobophora variegata) found in Hong Kong waters were investigated. Bromophenols were extracted by simultaneous steam distillation and solvent extraction apparatus and analyzed by gas chromatography-mass spectrometry. On a dried weight basis, the total bromophenol content (TBC) determined varied widely with seasons (from 40.9 to 7030 ng/g). The TBCs detected were higher in winter and lower in summer. Except for 2-bromophenol, the rest of the bromophenols were detected in all of the algal samples. The TBC of L. variegata was generally the highest among all of the algae collected. Relatively high concentrations of bromophenols in algae supported the fact that marine algae were major producers of bromophenols in the marine environment.