Volatile Components of the Phaeophyceae Hormophysa cuneiformis Growing Along Qatar Coasts

Abstract

The present work deals with the study on volatile compounds from the brown alga Hormophysa cuneiformis collected from the Northwest coast of Qatar on May 2002. Two extraction methods have been used: conventional hydrodistillation of the crude diethyl ether extract of alga and supercritical CO2 extraction of the same crude extract with two different stationary phases for the trapping. The obtained oils were examined by GC/MS coupling experiments and the chemical compositions obtained from both methods were compared. Their major constituents were: squalene described for the first time from a macroalga, fatty acids and corresponding esters. It must be pointed out absence of volatile C-l 1 hydrocarbons which are commonly presents in brown algae might be due to the collecting period of the alga (May) which probably favors the metabolism of unsaturated fatty acids precursors of these C-l 1 hydrocarbons. The presence, in a small amount, of a C-l 1 sulphur compound with a near related biogenesis of the volatile C-ll hydrocarbons is in agreement with this hypothesis.