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3- Marine Organisms as Sources of Useful Materials

Since ancient times, man has harvested marine organisms both as food and as a source of

useful materials. In the past two or three decades, however, three major areas can be

clearly identified:

(1) The exploitation and management of the natural resources,

(2) The transition from harvesting the marine environment to farming those useful

species through aquaculture technology; and

(3) The increased interest in screening marine organisms as potential sources of

bioactive compounds of potential medical and agricultural interest.

Bioactive compounds are natural compounds produced by certain organisms and affect

the growth, metabolism, reproduction, and survival of other types of organisms. Those

include potentially effective therapeutic agents with antiviral, antibacterial, and antitumor

properties produced mainly by invertebrates from the classes Porifera (e.g. sponges),

Cnidaria, Mollusca, Echinodermata, Bryozoa, and Urochordata.

Sessile Marine Organisms as Potential Sources of Natural Products

The immobile existence of sessile (non-mobile or permanently attached) organisms such

as reef-building corals, sponges, sea fans, bryozoans, tunicates and macroalgae, gives rise

to its own problems. Chief among these is the need to keep from being eaten, the need to

keep from being fouled or overgrown, the need to successfully reproduce, and the need to

ward off microbial infections. These organisms often rely on secondary metabolites, or

biochemical 'natural products' to overcome many of the difficulties of life.

1. Natural Products Keep Marine Organisms from Being Eaten

Natural products can be toxic or noxious (bad tasting/smelling) to would-be consumers of

sessile organisms. Various marine macroalgae, sponges, and other organisms avoid being

eaten because they produce and sequester these products.

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2. Natural Products Allow Marine Organisms to Maintain Space

Sessile organisms are potentially susceptible to overgrowth, or crowding out by

competitors. For example, the photosynthetic organisms like macroalgae (seaweed),

crowding by other organisms is detrimental because it can shade the algae. To reduce

competition, some seaweed, sponges, and other sessile organisms use a chemical

defensive strategy called allelopathy. Allelopathy is the suppression of growth of one

species by another due to the release of toxic substances.

3. Natural Products Help Ensure Survival Success

The vast majority of sessile invertebrates produce free-living, planktonic larvae. A

planktonic larval stage is certainly an effective means of broadcast-dispersal of larvae,

but at the time of settlement, the larvae must be able to successfully locate habitats

meeting their specific juvenile and adult survival needs.

Since the ability to correctly recognize and settle into suitable habitat is literally a matter

of life and death, it is not surprising that many marine invertebrate larvae possess a

remarkable ability to 'smell their way' onto appropriate settlement sites. This revolves

around the ability of larvae to sense and home in on waterborne chemical cues originating

from adult conspecifics, favored adult prey items, or reliable co-occurring organisms.

Almost as important, chemical cues can also elicit an avoidance behavior in larvae, e.g.,

if the cues in question indicate the presence of large numbers of potential predators.

4. Natural Products Protect Marine Organisms Against Infections

Large number of marine natural products demonstrate pronounced antibiotic, antiviral, or

antifungal properties suggests that these compounds may well play a similar role in

nature. In marine environment as many as 1 million bacterial cells in a single milliliter of

seawater, what would be truly surprising is if sessile organisms in the marine

environment didn't have a way to naturally defend themselves against potential infection

and disease.

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Examples of Useful Materials from Marine Organisms

Medical Applications of Aquatic Biotechnology

Many scientists believe that oceans and freshwater habitats possess near limitless

opportunities for the identification of medical products. In the future, it is anticipated that

new and important classes of drugs will be derived from aquatic organisms and used for

human benefit, and marine organisms may be used as biomedical models to understand,

diagnose, and treat human diseases.

Chitin White, horny substance found in the exoskeleton of the phylum Arthropoda— which

includes crabs, lobsters, and shrimp. It is a polysaccharide consisting of units of N-acetyl

glucosamine.

Because of its unique properties, together with its by-products, chitosan, chitotriose, and

chitobiose, it has found applications in industries, medicine, and agriculture. These

complex carbohydrates are structurally similar to cellulose, which forms the tough outer

layer of the cell wall in plants. Cellulose is widely known as a source of dietary fiber.

Similarly, chitin and chitosan are also sources of fiber. Eating vegetables and fruits to get

fiber is much gentler on your digestive tract than eating crab shells. Nonetheless, ground-

up extracts of crab shell can be purchased as a powder in many nutrition stores. Today,

more than a million people worldwide take chitin and chitosan in dietary supplements.

Their antibacterial, anti-fungal and anti-viral properties make them particularly useful for

applications. Research has shown that chitin and chitosan are non-toxic and non-

allergenic, so the body is not likely to reject these compounds as foreign invaders. Many

skin creams and contact lenses also contain chitin, and chitin has been used to create

nonallergenic dissolvable stitches that appear to stimulate healing when used in humans.

Production

• Start material head and shell of shrimp

• Chemical/Biochemical Process

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Chitosan

Chitosan is a natural product which is derived from the Polysaccharide chitin. It is a

Polysaccharide consisting units of the amino sugar D-Glucosamine.

The Chitosan has the unique ability to attach itself to lipids or fats. Chitosan fiber differs

from other fibers in that it possesses a positive ionic charge. This positive charge gives

Chitosan the ability to bind with negatively charged lipids, fats and bile acids.

There are no calories in Chitosan since it is not digestible. Chitosan attaches to fat in the

stomach before it is metabolized. The Chitosan traps the fat and prevents its absorption in

the digestive tract. The fat binds to the Chitosan fiber and becomes a large mass which

the body cannot absorb. This large mass is then eliminated from the body.

This dietary fiber is a valuable addition to a properly balanced weight management

program. Fibers also provide important cleansing attributes which aid in the digestive

process and promote digestive tract health. Chitosan can also help to lower cholesterol.

Glucosamine

This product is natural amine sugar extracted from the Chitin. As food additive and raw

material for pharmacy, it provides the building blocks for the body to make and repair

cartilage.

Monitoring Health and Human Disease

Limulus amoebocyte lysate (LAL) test The limulus amoebocyte lysate (LAL) test is an extract of blood cells (amebocytes) from

the horseshoe crab Limulus polyphemus that is used to detect bacterial endotoxins.

Endotoxins, also called lipopolysaccharides, are part of the outer cell wall of many

bacteria such as E. coli and Salmonella. Researchers discovered that horseshoe crab

blood would clot when exposed to whole E. coli or purified endotoxins. They later

determined that amebocytes— which are similar to human white blood cells—in

horseshoe crab blood could be lysed, centrifuged, and freeze-dried to create a lysate that

can be used in an LAL test.

Endotoxins are a type of cytotoxins, molecules that are toxic to cells. Endotoxins can

cause instant death to many cells grown in culture. In humans, exposure to endotoxins

from certain bacteria can result in mild symptoms such joint pain, inflammation, and

fever to more severe conditions such as a stroke. Certain endotoxins can be lethal.

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The LAL test, a rapid and very effective assay

for endotoxins in human blood and fluid samples,

to ensure that cytotoxins are not present in biotechnology drugs such as

recombinant therapeutic proteins.

It is also used to detect bacteria in raw milk and beef.

In addition, many medical companies and hospitals use the LAL test to make sure

that surgical instruments, needles used for drawing blood and cerebrospinal fluid,

and implanted devices are endotoxin free.

The LAL test is the most sensitive and specific procedure available for the detection of

bacterial endotoxin because it can detect as little as 1 pg.

Calcitonin Salmon for Osteoporosis treatment

Osteoporosis, a condition characterized by a progressive loss of bone mass, creates

porous and brittle bones that can lead to fractures of the hip, legs, and joints, which

severely hinder an individual‟s lifestyle. Over 90% of the roughly 25 million Americans

affected by osteoporosis are women. A common treatment for osteoporosis is estrogen

therapy. This medication is ineffective for many women, and the long-term health effects

of estrogen are a concern. Other individuals are treated with human recombinant

calcitonin, a thyroid hormone that stimulates calcium uptake and bone calcification and

inhibits bone-digesting cells called osteoclasts. Recently, researchers have discovered

that some species of salmon produce a form of calcitonin with a bioactivity that is 20

times higher than that of human calcitonin. Cloned forms of salmon calcitonin are now

available for delivery as an injection form and a nasal spray.

Coralline hydroxyapatite bone graft substitute

The skeletons of reef forming corals partially consist of hydroxyapatite (HA) (a calcium

phosphate mineral), an important component of the matrix that constitutes bone and

cartilage in animals including humans. The biotechnology company Interpore

International has developed technology that allows HA implants to be cut into small

boxes and used to fill gaps in fractured bones. These boxes are ultimately invaded by

local connective tissue cells that speed repair. As a result, patients avoid needing bone

grafts from other parts of their body. These implants may also serve to fill bone material

lost around the root of a tooth.

Adhesives substances A number of adhesives have been identified in glue-like substance produced by mussels

and other shellfish. The mussels (Mytilus edulis) are

hinged shelled mollusks that live in harsh, physically

demanding environments. They typically adhere to rocks

or pilings at the edges of oceans. Day after day, these

creatures are pounded by waves. They dry out during low

tides, then get submerged and pounded by waves again as

the tide rises. How do they maintain their contacts to

rocks and other structures without being crushed or pulled

off the rocks? The answer lies in a unique form of

protein-rich superadhesive called byssal fibers (Figure ).

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Byssal fibers are several times tougher and more extensible than human tendons, which

themselves are tougher than steel. Adhesive and elastic properties of byssal fibers absorb

energy and stretch as waves tug away at the mussels. Although it would be cost

prohibitive to isolate byssal fibers from mussels directly (nearly 10,000 mussels would be

required for 1 gram of adhesive), scientists are using recombinant DNA techniques to

express the byssal fiber genes in bacteria and yeast to produce these adhesive proteins on

a large scale.

Although still several years from development, byssal fiber proteins are being considered

for a wide variety of diverse applications from automobile tires to shoes and from bone

and teeth repair strategies to soft body armor for soldiers. Other potential uses include

surgical sutures and artificial tendon and ligament grafts.

Manoalide Researchers have identified a Pacific sponge that produces a nonsteroidal compound

called manoalide. This substance possesses anti-inflammatory and analgesic properties

and is currently being investigated in clinical trials in humans.

Anticancer compounds Over a dozen different anticancer compounds have been isolated from marine

invertebrates, particularly sea sponges, tunicates, and mollusks. Many of these

compounds are in various stages of clinical trials that will ideally lead to new and

effective drugs on the market.

Conotoxins Several groups of researchers are studying venomous marine creatures with the hope of

identifying substances that may be used to

treat nervous system disorders.

Marine cone snails, a potentially lethal

species, produce conotoxins, molecules that

can target specific neurotransmitter

receptors in the nervous system. In 2004, the

FDA (Food and Drug Administration)

approved the drug Prialt, a peptide

conotoxin purified from the marine cone

snail Conus magus. Conotoxins such as

Prialt represent a promising new source of

neurotoxins with the ability to act as strong

painkillers by blocking neural pathways

that relay pain messages to the brain. Prialt

has been successfully used to treat chronic,

severe forms of pain such as back pain.

Anti-inflammatory compounds Researchers are also examining anti-inflammatory compounds found in coral extracts.

Such compounds may lead to new treatment strategies for skin irritations and

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inflammatory diseases such as asthma and arthritis. Table 4 lists examples of medical

compounds isolated from aquatic organisms.

Table 4 Examples of Medical Compounds from Aquatic Organisms

Researchers are developing culturing systems to provide adequate supplies of marine

organisms such as single-celled plankton called dinoflagellates, which contain

antitumor and cancer-treating abilities.

A Bryozoan's Medical Endosymbiont

Recently, a marine invertebrate belong to Bryozoa and called Bagula neritina was

shown to contain minute amounts of a compound that is active against certain types of

leukemia and Alzheimer. In fact it's not the bryozoan that makes the chemical. The

chemical, found in the bryozoan's tissues, is produced by its bacterial endosymbiont,

Candidatus Endobugula sertula. In exchange for a protective home in the bryozoan's

tissues, the bacteria produces a chemical called a bryostatin that makes the bryozoan

larvae taste bad to predators.

Nerve cell toxin from the pufferfish (Fugu rubripes)

The Japanese pufferfish, or blowfish (Fugu rubripes), has been getting a lot of attention

lately. Fugu is famous for its ability to swallow water and „puff up” when threatened and

to produce a potent nerve cell toxin called tetrodotoxin (TTX). TTX is one of the most

toxic poisons ever discovered (nearly 10,000 times more lethal than cyanide). In Japan,

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Fugu is a prized and very expensive delicacy for many sushi lovers who enjoy the food

quality of this tasty fish despite the risk (eating Fugu kills pearly 100 people, mostly in

Japan, each year). Scientists have used TTX to develop a greater understanding of how

proteins called sodium channels help neurons produce electrical impulses. TTX is a

deadly poison because it blocks sodium channels and prevents nerve impulse

transmission. An understanding of how TTX affects sodium channels has led to the

development of new drugs that are being tested not only as anesthetics to treat patients

with different types of chronic pain but also as anticancer agents in humans.

Figure 14 Pufferfish are Helping Scientists Discover New Wags to Treat Cancer and Chronic Pain.

Researchers are also working on sequencing the pufferfish genome, which contains

nearly the same number of genes as humans but in a much smaller genome. Fugu also

contains far less noncoding DNA (introns) than humans, so it is considered an ideal

model organism for studying the importance of introns.

Squalamine form dogfish A steroid called squalamine, first identified in dogfish sharks (Squalus acanthias),

appears to be a potent antifungal agent that may be used to treat life-threatening fungal

infections that can fatally affect patients with conditions such as AIDS and cancer.

Sharks rarely develop cancer, and shark cartilage has been proposed to be a rich source of

anticancer agents. Although no compounds from shark cartilage have demonstrated

effectiveness in controlled clinical trials, shark cartilage extracts possess antiangiogenic

compounds. Angiogenesis is the formation of blood vessels, a process that is often

required for growth and development of many types of tumors. By blocking blood vessel

formation, antiangiogenic compounds derived from marine species show promise for

inhibiting the growth of certain tumors.

Natural sunscreens Because many aquatic organisms live in harsh environments, scientists are optimistic that

they can learn from the adaptations these organisms have developed. For example,

researchers are currently studying marine organisms that show tolerance to ultraviolet

light as a potential source of natural sunscreens.

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Drugs from the sea

To date, few drugs from the sea have widespread use in the medical market; however, in

the future, recombinant DNA technologies will lead to enhanced abilities to produce bulk

quantities of bioactive compounds typically found in very low concentrations in aquatic

organisms. The next table presents the marine-derived potential therapeutic compounds.

Many of these are still undergoing preclinical evaluation, but several others are currently

being administered to patients as part of clinical trials. Information provided for each

product entry includes compound source, bioactivity, and clinical status.

Some promising potential therapeutic compounds derived from marine sources

Source Compound [clinical status] Activity

Microbe-Derived

Compounds

Cryptophycins [Clinical trials of

semi-synthetic cryptophycin 52

discontinued in 2002]

Antifungal , Cytotoxins ,

Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Curacin A [Preclinical] Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Thiocoraline [Preclinical] DNA Polymerase

Inhibition

Sponge-Derived

Compounds

Bengamides and Derivatives

[Synthetic analog LAF389

withdrawn from Phase I clinical

trials in 2002]

Antitumor/Tumor

Growth Inhibition

Contignasterol (IZP-94005,

IPL576,092) [In clinical trials

(various phases]

Anti-Asthma Agent

Debromohymenialdisine (DBH)

[Phase I clinical trials]

Anti-Alzheimer Agent,

Osteoarthritis Treatment

Discodermolide [Phase I clinical

trials]

tubule interactive agent

Girolline (Girodazole) [Clinical trials

discontinued]

Protein Synthesis

Inhibition

Halichondrins [Synthetic analogs are

currently in clinical trials]

Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Hemiasterlins (H-286) [Preclinical] Cytotoxins ,

Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

KRN7000 [Phase I clinical trials

(Europe and Asia)]

Antitumor/Tumor

Growth Inhibition,

Immunostimulatory

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Lasonolides []Preclinical Antifungal,

Antitumor/Tumor

Growth Inhibition

Manoalide [Withdrawn from Phase

II clinical trials]

Analgesia, Anti-

Inflamatory

Topsentins [Preclinical] Anti-Inflamatory

Dictyostatin [Preclinical] Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Latrunculins [Preclinical] Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Laulimalide (and Synthetic Analogs)

[Preclinical]

Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Manzamine A [Preclinical] Anti-Infective Agent ,

Antitumor/Tumor

Growth Inhibition

Peloruside A [Preclinical] Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Salicylihalamides [Preclinical] Vo-ATPase Inhibition

Cnidarian-Derived

Compounds

Pseudopterosins [: in use as a

commercial skin cream additive; in

preclinical development for medical

applications]

Analgesia, Anti-

Inflamatory

Eleutherobin [Preclinical] Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Sarcodictyins [Preclinical] Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Helminth-Derived

Compounds

Anabaseine (Hoplonemertine toxin)

[Phase I clinical trials]

Anti-Alzheimer Agent

Molluscan-Derived

Dolastatins [Phase II, Phase I

clinical trials]

Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Kahalaide F Cytotoxins , Gene

Inhibition

Spisulosine [Currently in Phase I

clinical trials]

Antitumor/Tumor

Growth Inhibition

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Ziconotide (Prialt®) [FDA-

Approved]

Analgesia

Bryozoan-Derived

Compounds

Bryostatin 1 [In Phase II clinical

trials]

Immunosuppressive,

Protein Kinase C

Binding Inhibition

Ascidian-Derived

Compounds

Aplidine (Aplidin®) [Phase II

clinical trials]

Apoptosis Induction

Didemnin B [Withdrawn from

clinical trials]

Protein Synthesis

Inhibition

Ecteinascidin 743 (Yondelis®) Apoptosis Induction

Diazonamide A [Preclinical] Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Vitilevuamide [Preclinical] Tubulin/Actin

Interactive Agents

(primarily anti-cancer)

Vertebrate-Derived

Compounds

Squalamine [Phase I/Phase II clinical

trials; also sold as a non FDA-

approved dietary supplement]

Anti-Angionegic Agent,

Antitumor/Tumor

Growth Inhibition

Neovastat® (AE-941) [Preclinical] Anti-Angionegic Agent ,

Antitumor/Tumor

Growth Inhibition

Clinical Trials

Clinical trials of new drug candidates for safety and efficacy evaluation are mandatory before a

drug candidate is cleared for marketing. The new candidate drugs are approved for clinical

practice, after they have been evaluated in different phases of clinical trials phase I to phase II to

phase III

In phase I clinical trials, the tolerability of the test compound in different doses in healthy

volunteers is first assayed.

In Phase II clinical trials, the therapeutic effects of the test drug are carefully monitored in

patients.

In phase III clinical trials, data on several thousands patients in various well-defined indications

are collected.

Marine microorganisms Many of the compounds isolated from marine organisms, such as sponges, may be

produced by associated bacteria. For example:

- Several diketopiperazines previously ascribed to the sponge Tedania ignis, are

produced by a marine Micrococcus sp. associated with this sponge.

- The halichondrins, complex polyether macrolides are originated in microbial flora

components from the marine sponge Halichondria okadai. Halichondrin B, an

extremely potent antimitotic agent, inhibits tubulin polymerization and microtubule

assembly.

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Non-medical Products Enzymes from the sea

Taq polymerase, isolated from hot-springs Archae Thermus aquaticus, which allowed

for the development of the PCR as a powerful tool in molecular biology.

Heat-stable ligases and restriction enzymes The ocean also has proved to be an

excellent source of enzymes and other products that have played an important role in

basic and applied research. For example, bacteria living near hydrothermal vents have

yielded a second generation of heat-stable enzymes for use in PCR and DNA-modifying

enzymes, including ligases and restriction enzymes.

Salt resistant enzymes Other enzymes produced by marine bacteria possess a variety of

interesting properties that may result in important applications in the future. For example,

some enzymes are salt resistant, which renders them ideal for industrial scale-up

procedures involving high-salt solutions.

Bioluminescent Marine Bacteria

Useful products from Bioluminescent Marine Bacteria In addition of detecting environmental pollution by the bioluminescent bacterium Vibrio

harveyi, researchers have discovered marine species of Vibrio that produce a number of

proteases, including several unique proteases that are resistant to detergents used in

many manufacturing processes. As a result, these detergent-resistant proteases may have

potential applications for degrading proteins in cleaning processes, including their use in

laundry detergent for removing protein stains in clothes.

Vibrio is also a good source of collagenase, a protease used in tissue culturing to digest

the connective tissues holding cells together so the individual cells can be dispersed into

cell culture dishes.

Bioluminescent Marine Bacteria, a source of Lux Genes

According to recent estimates, close to three fourths of all marine organisms can release

light through a process known as bioluminescence. For marine fish, bioluminescence can

be used to attract mates in dark ocean environments. Bioluminescence in many marine

species is created by bacteria such as Vibrio fischeri that use the marine organism as a

host (Figure 15).

Fig. Bacterial luminescence. Colonies of P. mandapamensis from the light organ of the cardina fish

Siphamia tubifer are shown growing on a nutrient seawater agar plate. The plate was photographed in

room light (left) and (the same plate) in the dark by the light produced by the bacteria (right).

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Bacteria such as Vibrio have been used as biosensors to detect cancer- causing chemicals

called carcinogens, environmental pollutants, and chemical and bacterial contaminants in

foods. Vibrio fischeri and another marine bioluminescent strain called Vibrio harveyi

create light through the action of genes called lux genes. Several lux genes encode

protein subunits that form an enzyme called luciferase (derived from the Latin lux ferre,

meaning “light bearer”).

Figure 15 Bioluminescent Marine Bacteria, a source of Lux Genes Bioluminescent marine bacteria, such

as Vibrio fischeri shown (above) glowing in the light-releasing organs of a deep-sea fish and (below) Lux

genes encode the enzyme luciferase that uses oxygen and stored energy (ATP) to convert luciferin into

oxyluciferin. This reaction releases light. Lux genes have served important roles as reporter genes to allow

biologists to study gene expression. By cloning genes into plasmids containing lux genes, expression is

indicated by glowing cells.

The lux genes have been cloned and used to study gene expression in a number of

unique ways

The lux genes can also serve as valuable reporter genes. If inserted into animal or

plant cells, the luciferase encoded by the lux plasmid cause these cells to fluoresce

(Figure 15). In this manner, the lux plasmid is acting as a “reporter” to provide a

visual indicator of gene expression.

Lux genes have recently been used to develop a fluorescent bioassay to test for

tuberculosis (TB). TB is caused by the bacterium Mycobacterium tuberculosis,

which grows slowly and can exist in a human for several years before the individual

may develop TB. For the TB bioassay, scientists introduced lux genes into a virus

that infects M. tuberculosis. Saliva from a patient who may be infected with M.

tuberculosis is mixed together with the lux-containing virus. If M. tuberculosis is in

the saliva sample, the virus infects these bacterial cells, which can be detected by

their glowing.

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Biomass and Bioprocessing

One newly emerging area of marine biotechnology involves the exploration of marine

biomass. A mat of aquatic weeds of algae represents biomass, as does a school of fish.

Marine plants (including seaweeds, grasses, and planktons) use photosynthesis to capture

and convert a tremendous amount of energy (nearly 30% of all energy production

worldwide) from the sun into chemical energy. Can chemical energy from such biomass

be harvested? Scientists are examining ways in which algae and plants may he used to

produce alternative fuels. For example, it may be possible to take advantage of the rapid

biosynthetic capabilities of marine algae with their ability to mass-produce hydrocarbons

and lipids in extraordinary quantities to provide alternate sources of materials that are

normally cost prohibitive to produce or isolate from natural materials. Similarly, it may

be possible to convert marine biomass into fuels such as ethanol.

The U.S. Naval Research Lab has investigated potential ways to use plankton as

underwater “fuel cells”. Plankton at the water‟s surface release energy as they undergo

photosynthesis, whereas plankton closer to the sediment at the bottom of the ocean

(where there is less oxygen) use other reactions to generate energy. As a result, scientists

have found that these plankton create a natural voltage gradient from the surface to the

ocean floor that can be harvested to produce an indefinite source of electricity. In the

future, the ocean may turn out to be a valuable resource for providing energy.

Lastly, scientists are exploring ways in which biomass of marine algae may be used to

increase absorption of carbon dioxide and decrease greenhouse effects on the earth.

Related to applications of biomass, marine scientists are exploring ways in which

bioprocessing may involve marine products. Bioprocessing is a general term that

describes engineering approaches to produce a biological product such as a recombinant

protein (Proteins that can result from the expression of recombinant DNA within living

cells). Algae may potentially be very valuable for expressing recombinant proteins.

Researchers have found that they can make an abundance of proteins, such as antibodies,

in marine algae because they can be grown on a very large scale.

Marine biologists are exploring how marine organisms may be used to synthesize a

variety of polymers and other biomaterials, which may be used for industrial

manufacturing processes. For instance, oyster shell proteins are being considered as

additives in detergents and other solvents as nontoxic, biodegradable alternatives to

currently used materials.