Quantifying Caffeine Produced by a Marine Diatom

Krista Longnecker, Marine Chemistry & Geochemistry



Caffeine derived from tea and coffee plants is enjoyed daily by over 85% of US citizens.  The presence of caffeine in wastewater and groundwater has led to the use of caffeine as a marker of anthropogenic activity.  Yet, during a small-scale laboratory experiment, I observed the production of caffeine by the diatom Thalassiosira pseudonana.  The proposed project will allow me to quantify the amount of caffeine produced by this model marine diatom.  This research will be of interest to multiple groups within the scientific community and the general public.  First, caffeine is one of the few easily recognized organic compounds.  Therefore, the project results will attract the attention of our local community and thereby bring renewed interest to the research conducted by WHOI on the chemistry of the coastal ocean.  For the scientific community, the project will quantify a previously unknown source of caffeine which may require a reconsideration of the use of caffeine as a marker for anthropogenic activity.  Furthermore, in a similar manner to terrestrial plants, diatoms may use caffeine as a grazer- and microbial-deterrent.  Therefore, this project will present a new avenue for research into the use of chemical compounds to mediate microbial interactions in marine environments.