- 第3日 5月21日（金） P2会場（Zoom）
Off-flavor events in raw waters for tap water supply have been reported from various regions of Japan. Although fishy smell is the second most common off-flavor, its causative compounds is still unrevealed to the best of our knowledge. The authors previously reported one candidate substance and determined its molecular formula as C13H20O3. Its partial structural elucidation was also performed, however, much effort is still required for complete identification. In this study, a detailed structural elucidation of C13H20O3 was performed by combining GC/HRMS with LC/HRMS. GC/HRMS analysis suggested that C13H20O3 contains a methoxy group, a cyclohexene ring, and two ketone groups. One of the two ketone groups is a terminal ketone to which a propyl or a butyl chain is attached.
Because we previously hypothesized that C13H20O3 had a hydroxyl group instead of a methoxy group, alternative fragmentation pathways for three neutral losses (C2H2O, C2H4O, and C3H6O) which had been observed in our previous LC-HRMS analysis of the derivatized C13H20O3 were also proposed adopting a methoxy group in order to get rid of this contradiction.