surrounding seas, which contain spores of terrestrial fungi
coincidentally found in these waters. Isolation of a fungus
from a marine organism also does not indicate whether the
fungus is an obligate or facultative marine organism. Obligate
marine fungi are de®ned as those fungi which grow and
sporulate exclusively in a marine environment. In contrast,
facultative marine fungi are from freshwater or terrestrial
habitats and are also capable of growing in the natural marine
habitat (Kohlmeyer 1974).
The goal of our studies was to investigate the potential of
fungi isolated from sponges to produce a high proportion of
unknown natural fungal products. Fungi were isolated from
sponges from varied climatic and geographical marine habitats,
and their culture extracts tested for biological activity in tests
for both pharmaceutical and agrochemical indications. The
structures of the biologically active metabolites were elucidated;
some are reported here.