WULFF, ANGELA* and MONICA APPELGREN. Dept of Marine Ecology, Marine Botany, Goteborg University, Sweden. - Mycosporine-like amino acids in harmful marine microalgae.
Two current environmental issues are the increasing occurrence of
harmful algal blooms and the increasing level of ultraviolet
radiation. The objective of this ongoing project is to investigate
whether there is a coupling between these two phenomena, i.e. to test
the hypothesis that UV-B radiation functions as a selective pressure
favouring surface-blooming toxic/harmful marine microalgal species
capable of producing UV-absorbing compounds (mycosporine-like amino
acids, MAAs). A series of experiments were designed to test if the
light environment induces the production of MAAs. Treatments were PAR
with and without the addition of UV-B radiation. Preliminary results
show a different response for different species. Most species
increased their production of MAAs when exposed to an increased PAR
intensity (300 µmol photons m-2 s-1) and in e.g. Alexandrium
ostenfeldii and Gyrodinium aureolum a further increase
was observed upon exposure to UV-B radiation. The content and
composition of MAAs for a number of potentially harmful marine
microalgae will be shown. In addition, the outcome of small changes in
the HPLC method used will be discussed.
Key words: MAA, marine, microalgae, mycosporine-like amino acids