On the widespread occurrence of 3-methylidene-7,11,15-trimethylhexadecan-1,2-diol in the marine environment: a specific isoprenoid marker of chlorophyll photodegradation

3-Methylidene-7,11,15-trimethylhexadecan-1,2-diol (phytyldiol), a specific isoprenoid marker of chlorophyll photodegradation, was identified by GC–EIMS from a number of marine water particles, sediment trap material and Quaternary marine sediment samples. The widespread occurrence of this marker gives for the first time measurable evidence of chlorophyll photodegradation process in marine ecosystems. The use of the molar ratio phytyldiol to phytol is proposed for the study of the photodegradation processes of chlorophyll occurring in the photic layer of the oceans.