DMS in the odor landscape of the sea Dimethyl Sulfide or DMS is
present throughout the ocean(1). It’s an important odor
component of many fish and shellfish, including clams, mussels,
oysters, scallops, crabs and shrimp(2-9). Where does it come
from? Usually from the marine plants they feed on. Many species
of plants and algae produce DMS, but not all species produce
significant amounts of it. Nearly all of these are marine, and
they tend to be in closely related groups with other DMS-
producers, including Chlorophyte (green) seaweeds, the
Dinophyceae in the dinoflagellates, and some members of the
Chrysophyceae and the Bacillariophyceae (two classes of
diatoms). Other large groups, like cyanobacteria and freshwater
algae, tend not to produce DMS. (10,11) Why do these groups
produce DMS? In algae, most researchers believe a related
chemical, DMSP, is used by the algae for osmoregulation- by
ensuring the ion concentration inside their cells stays fairly
close to the salinity in the seawater outside, they preven