MARINE biotechnology is an emerging discipline based on the use of marine natural resources. The oceans encompass about 71 per cent of the surface of our planet, but over 99 per cent of the biosphere (since organisms are found throughout the water column), and they represent the greatest extremes of temperature, light, and pressure encountered by life.

Adaptation to these harsh environments has led to a rich marine bio- and genetic-diversity with potential biotechnological applications related to drug discovery, environmental re-mediation, increasing seafood supply and safety, and developing new resources and industrial processes.

Drug discovery represents one of the most promising and highly visible outcomes of marine biotechnology research. Bio-chemicals produced by marine invertebrates, algae and bacteria are very different than those from the related terrestrial organisms and thus offer great potential as new classes of medicines.

To date, examples of marine-derived drugs include an antibiotic from a fungi, two closely related compounds from a sponge that treat cancer and the herpes virus, and a neurotoxin from a snail that has painkiller properties making it 10,000 times more potent than morphine (painkiller) without the side effects.

However, there are several more marine-derived compounds currently in clinical trials and it is likely that many more will advance to the clinic as more scientists look to the sea for these biotechnological uses.

In addition to new medicines, other uses for marine-derived compounds include: cosmetics (algae, crustacean and sea fan compounds), nutritional supplements (algae and fish compounds), artificial bone (corals), and industrial applications (fluorescent compounds from jellyfish, novel glues from mussels, and heat resistant enzymes from deep-sea bacteria).

Between 40 and 50 per cent of all drugs currently in use, including many of the anti-tumour and anti-infective agents introduced during the 1980s and 1990s, have their origins in natural products. Most of these were derived from terrestrial plants, animals, and micro-organisms, but marine biotechnology is rapidly expanding.

After all, 80 per cent of all life forms on Earth are present only in the oceans. Unique medicinal properties of coral reef organisms were recognised by Eastern cultures as early as the 14th century, and some species continue to be in high demand for traditional medicines.

In China, Japan, and Taiwan, tonics and medicines derived from seahorse extracts are used to treat a wide range of ailments, including respiratory and circulatory problems, kidney and liver diseases, throat infections, skin ailments, and pain.

In recent decades, scientists using new methods and techniques have intensified the search for valuable chemical compounds and genetic material found in wild marine organisms for the development of new commercial products.

Until recently, however, the technology needed to reach remote and deepwater reefs and to commercially develop marine biotechnology products from organisms occurring in these environments was largely inadequate.

The prospect of finding a new drug in the sea, especially among coral reef species, may be 300 to 400 times more likely than isolating one from a terrestrial ecosystem.

Although terrestrial organisms exhibit great species diversity, marine organisms have greater phylogenetic diversity, including several phyla and thousands of species found nowhere else.

A gel made from seaweed and used in ice-cream and toothpaste could be used to protect women against the HIV, scientists suggest. The gel has already proved effective in blocking sexually-transmitted diseases in animals, including herpes and gonorrhoea. Scientists now hope it could offer a cheap way to help stop the spread of AIDS in the developing world, according to an article in the Wall Street Journal.

Coating artificial hips, heart valves and other medical implants with a type of seaweed could prevent patients from contracting life-threatening infections, research suggests. A study carried out by scientists in Australia has found that chemicals in marine algae can fight the bacteria that cause many of the infections associated with surgery. Some of these infections are caused by bacteria, which normally lives harmlessly on skin, attaching themselves to implants during operations.

A protein found in seaweed could help explain why some malignant cancer cells spread to other parts of the body. Scientists believe the protein lectin could explain the chemical changes which cause some cancer cells to spread.

A novel microbe found in marine sediments is able to convert sugar into electricity with a higher efficiency than any previously known organism. Because sugar is abundant in the environment, a battery using the new microbes could provide economical electricity in remote places. While the prospects are good, the researchers say more work needs to be done before their research can be exploited commercially.

Biotechnology also holds the promise of increasing food supplies from the ocean; this is critical as over-fishing and an increased demand have taxed the limits of marine sustainable stocks.

Aquaculture techniques have been enhanced by the discovery of natural inducers for spawning and larval settlement, as well as remediation of disease within culture facilities.

Molecular genetic studies are applied to fisheries to identify natural populations and mixed stock interactions, and to estimate stocking efficiencies with pedigree. More recently, biotechnology has been used to assess seafood safety through the development of novel test kits that react to the presence of human pathogens in the food.

These “biosensor” techniques are currently being employed as early warning systems for environmental health. For example, harmful algal blooms and/or anthropogenic toxins have the potential to cause great harm to marine habitats.

Unique biosensors are being developed to inform scientists of increasing levels of specific biomarkers. Moreover, specific marine bacteria have been developed that can aid in the clean-up effort if a toxic spill should occur; thus biotechnology not only helps society, but it helps the environment as well.