Drugs from the Sea
After forty years of research the
chemistry of marine products has become a mature field. A very large
number of
metabolites with useful and remarkable pharmacological properties have
been
reported. Marine biotechnology has been applied to areas of public
health and
human disease and marine ecosystem restoration and redemption.
The need
for drugs to control new illnesses and resistant strains of
microorganisms led
to the search for new bioactive products.
The search for new biomedical
from marine
organisms has resulted in the isolation of approximately ten thousand
metabolites, many of which have pharmacodynamic properties. Included in
this
broad spectrum are antibiotic, anti fungal, toxic, cytotoxic, anti
viral and antibiotic
properties. Many soft bodied marine invertebrates produce
bioactive
compounds as elements of a chemical defense mechanism. The
Okinawan
soft coral Clavularia Viridis contains many bioactive metabolites
called
prostanoids. Prostanoids specific to C. viridis are called clavulones.
In
addition to clavulones, structurally unique steroids and
prostanoid-related
compounds have also been isolated from C. viridis. Due to their
unique
chemical structures and strong anti tumor and cytotoxic activity these
prostanoids
have been the subject of continuous research.
The process of
collecting
marine organisms for research begins with obtaining permits. A site
must be
found that is both biologically diverse and dense so the collection of
specimens
does not affect the site. The collection is sorted and documented and
crude
samples are prepared for biological screening. Research on
prostanoids
has resulted in the isolation of about fifty chemical substances
possessing
similar functions to clavulones.
Although there
is a
large number of clavulones, and overall a very large number of marine
prostanoids with remarkable biomedical properties, their development
has been
slow due to the difficulty and expensive involved in collecting and/or
harvesting
the organism, the low yield of the compound, and isolation and
structural identification of the compound is too difficult
Environmental and
conservation issues must be considered in the collection of the
organism to
avoid over exploitation and degradation of the coral reefs. Conservation efforts include development of
management plans, development of synthetic derivatives of the
compounds, and
mass production of the target species through captive breeding or
mariculture.
In the last fifteen years 70 - 100% of the coral reefs throughout the
world
have died, including the coral reefs in
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