174
trials or in preclinical stage. A clear look into the list of these compounds shows an
alarming fact that the marine compounds are largely missing in the present pharmacopoeia. The ongoing research has increased confidence in scientists that marine
environment can hold a treasure of compounds that can replace the terrestrial compounds used in clinics. As marine environments occupy 95% of the biosphere, it
gives a clear indication of the treasure of compounds waiting to be discovered
(Jimeno et al. 2004). Even though the marine world has an enormous microbial
diversity, it is surprising that nearly 60% of the antibiotics in commercial production
are from cultivable soil microorganisms. Most of the marine microbes are not
friendly to traditional methods of culturing, and the few cultivable ones have laborious culturing methods, restricting the study of marine microbes.
During the evolution history of 3.5 billion years, of microorganisms, a wide
array of biosynthesis mechanisms has evolved and given rise to diversity of compounds in terrestrial organisms. The same diversity can be expected from the marine
ecosystem. Marine organisms have adapted to extreme environmental conditions of
salinity, pressure, and temperature. These extreme conditions in the marine environment enable the organism to explore novel pathways to produce unique compounds
with varying structural and functional characteristics (Kathiresan et al. 2008). The
future of these marine-based compounds as therapeutic agents is still in the cradle
stage, as they require further validation through clinical studies to reach clinics.
There are also problems related to the collection and processing of marine samples
which have led to retardation of work in this area. The marine microbial flora
encompasses a large diversity of bacteria, actinobacteria, cyanobacteria, and fungi.
The marine area in the form of ocean covers 71% of the earth, and the rich biodiversity has more than 90% contributed by microflora and microalgae with respective to
ocean biomass (Kathiresan and Duraiswamy 2005). In the late 1960s, researchers
began exploring the marine ecosystem in search of novel compounds of therapeutic
importance. A systemic approach to deal with isolation of marine compounds came
into being in the mid-1970s. The years between 1977 and 1978 saw a rise in discovery of novel compounds with therapeutic potential from marine flora, with the discovery of over 2500 new compounds with varying structures and functions.
Bryostatins, sarcodictyin, discodermolide, and eleutherobin are some of the anticancer compounds derived from marine bacteria. Marine animal phyla are known to
produce toxins, and research has revealed that symbiotic bacteria living in association with these animals are responsible for toxin production (Simidu et al. 1990;
Kodama et al. 1988). Noctiluca scintillans has association of a symbiotic bacteria
that produces the metabolite, macrolactin-A. This compound has the capability to
suppress B16-F10 murine melanoma cancer. Macrolactin-A also protects T lymphocytes against the attack and reproduction of human immunodeficiency virus
(HIV) (Carte 1966). Kahalalide F (KF) is a potent antitumor agent isolated from
marine organism, namely Hawaiian herbivorous marine mollusk Elysia rufescens
and alga Bryopsis. E. rufescens uses this compound as a deterrent against fish predators (Becerro et al. 2001). Initial studies investigating the possible symbiotic bacteria responsible for the production of KF have brought forward two probable
candidates, two strains of Vibrio species. Liquid chromatography-mass
V.M. Dan and R. Sanawar
trials or in preclinical stage. A clear look into the list of these compounds shows an
alarming fact that the marine compounds are largely missing in the present pharmacopoeia. The ongoing research has increased confidence in scientists that marine
environment can hold a treasure of compounds that can replace the terrestrial compounds used in clinics. As marine environments occupy 95% of the biosphere, it
gives a clear indication of the treasure of compounds waiting to be discovered
(Jimeno et al. 2004). Even though the marine world has an enormous microbial
diversity, it is surprising that nearly 60% of the antibiotics in commercial production
are from cultivable soil microorganisms. Most of the marine microbes are not
friendly to traditional methods of culturing, and the few cultivable ones have laborious culturing methods, restricting the study of marine microbes.
During the evolution history of 3.5 billion years, of microorganisms, a wide
array of biosynthesis mechanisms has evolved and given rise to diversity of compounds in terrestrial organisms. The same diversity can be expected from the marine
ecosystem. Marine organisms have adapted to extreme environmental conditions of
salinity, pressure, and temperature. These extreme conditions in the marine environment enable the organism to explore novel pathways to produce unique compounds
with varying structural and functional characteristics (Kathiresan et al. 2008). The
future of these marine-based compounds as therapeutic agents is still in the cradle
stage, as they require further validation through clinical studies to reach clinics.
There are also problems related to the collection and processing of marine samples
which have led to retardation of work in this area. The marine microbial flora
encompasses a large diversity of bacteria, actinobacteria, cyanobacteria, and fungi.
The marine area in the form of ocean covers 71% of the earth, and the rich biodiversity has more than 90% contributed by microflora and microalgae with respective to
ocean biomass (Kathiresan and Duraiswamy 2005). In the late 1960s, researchers
began exploring the marine ecosystem in search of novel compounds of therapeutic
importance. A systemic approach to deal with isolation of marine compounds came
into being in the mid-1970s. The years between 1977 and 1978 saw a rise in discovery of novel compounds with therapeutic potential from marine flora, with the discovery of over 2500 new compounds with varying structures and functions.
Bryostatins, sarcodictyin, discodermolide, and eleutherobin are some of the anticancer compounds derived from marine bacteria. Marine animal phyla are known to
produce toxins, and research has revealed that symbiotic bacteria living in association with these animals are responsible for toxin production (Simidu et al. 1990;
Kodama et al. 1988). Noctiluca scintillans has association of a symbiotic bacteria
that produces the metabolite, macrolactin-A. This compound has the capability to
suppress B16-F10 murine melanoma cancer. Macrolactin-A also protects T lymphocytes against the attack and reproduction of human immunodeficiency virus
(HIV) (Carte 1966). Kahalalide F (KF) is a potent antitumor agent isolated from
marine organism, namely Hawaiian herbivorous marine mollusk Elysia rufescens
and alga Bryopsis. E. rufescens uses this compound as a deterrent against fish predators (Becerro et al. 2001). Initial studies investigating the possible symbiotic bacteria responsible for the production of KF have brought forward two probable
candidates, two strains of Vibrio species. Liquid chromatography-mass
V.M. Dan and R. Sanawar