Does The Future Of Humanity Lie In Algae?

🔑 Genetic engineering enhances biofuel production by producing strains with desired traits and better energy conversion.

🔑  Crude oil (fossil fuels) originated from organisms such as algae that died and decayed millions of years ago.

Algae vary in size from microalgae (microscopic, filamentous and colonial forms of algae) to macroscopic kinds (such as seaweeds). They are absolutely ecologically important photosynthetic eukaryotic organisms and are the found af the aquatic food chain. They are the principal oxygen producers responsible for the production of over 50% of atmospheric oxygen. They are found almost anywhere in the world, dwelling on rocks, soils, water, and even on biological surfaces (epiphytes and epizoids).

Microphytes are phytoplankton usually found in marine environments and are quite common. They exist in microscopic unicellular or colonial forms. Common examples of these algae are volvox, Chlamydomonas, and the euglena. Plants such as kelp  (a common plant found in the sea bed) and sea lettuce are of comparatively substantial sizes (called macrophytes). 

Kelp, a brown seaweed and source of iodine. Kelp like other algae is not a plant. Photo courtesy: istockphoto.

Some algae are autotrophs while others may be heterotrophic. They usually contain photosynthetic pigments, although the type of pigment differ among different classes. They are broadly distinguished into several types based on physical appearance, morphology, and genetic and evolutionary relationships: These include Rhodophytes (Red algae) Phaeophytes (brown algae), chlorophytes (Green algae), Dinoflagellates and even the Euglenophytes.

🔑 True (vascular) plants are absent in marine systems. This means that algae serve as the primary food source for all marine life.

Diatoms are regarded a class of algae (bacillarophyceae). They are used as filters and absorbents.

Algae biofuels

Global warming is a widespread ecological challenge. Researchers have since been on the surge in coming up with innovations and strategies which not only meet global energy demands but halts the progression of global warming. We have seen a great lot of technologies such as fuel cells, hydrogen fuel, and biofuels. One upcoming innovation is the use of algae to generate biofuels which could potentially replace petroleum and other fossil fuels.

Algal fuels are plant-derived fuels (biofuels) that are manufactured from algae. The fuel consists of mainly oils although gases may be produced. These biofuels have a competitive energy profile with petroleum and are considered very good substitutes.

Capacities of algae-derived marine products

1. Instead of burning petroleum which introduces new Carbon dioxide into the air, algal fuels release CO2 which has already been absorbed by the algae. So there is no net introduction to the gas into the air. This therefore, means greenhouse release is put to a standstill.

2. Algae are fast generating plants that could be turned over within few weeks. Compared to trees, they have inferior structural complexity and metabolic demands making them more effective in converting CO2 into treasured fuels. Incredibly, algae can manufacture oils about 50% of their weight. This is higher than could be obtained from higher plants.

3. Algae are biodegradable. They present no harm to the environment (they were derived from the common environment). The waste material can be further transformed by bacteria into heavier fuels. 

4. Algaculture (the cultivation of algae for commercial purposes) could be performed In water deemed unsuitable for agricultural purposes (probably due to high organic content or fertilizers like phosphates and nitrates). Wastewater contains some organic fertiliser that encourages the growth of the algae giving more fuel. Hence they provide room for wastewater management. 

Algae bioreactor. Photo courtesy: istockphoto

What type of biofuels can we derive from algae?

1. Lipids: algae have a remarkable capacity to convert carbon into triglycerides (mono and polyunsaturated fatty acids). Surprisingly, these fatty acids could be essential in the human diet. The oils can be converted by microbes into simpler fuels like alcohols. They can otherwise be utilized as biodiesel.

2. Alcohol: industrial ethanol is chiefly produced commercially by fermentation of sugar cane. Algae or their sugars can be fermented and the alcoholic product extracted. Alcohols such as ethanol and butanol can be blended with or entirely replace gasoline in automobile and electrical engines. 

3. Hydrocarbons (Biogas and Biogasoline): biogas is mixtures of gaseous by-products that arise from anaerobic digestion of algal mass. These gases include methane, ethane, hydrogen, carbon dioxide. Macromolecules fixed in the cells/tissues are decomposed through redox and enzymatic processes, releasing gases as byproducts. In the complete absence of oxygen and for lengthened periods, hydrocarbons can be produced similar to the ones in gasoline. Biogasoline is cleaner than gasoline as its production and combustion do not disturb atmospheric levels of CO2.

Do you know algae have been utilized in numerous other ways? Some are briefly given below:

1. Pharmaceuticals: algae are good sources of antibiotics, antifungals, antiprotozoal and antivirals. Crude algal extracts have been found to inhibit the growth and multiplication of gram-positive and gram-negative bacteria. These products might be useful in clinical practices especially in fighting antibiotic microbial infections.

2. Pigments and dyes: chlorophylls and phycobilins (which are only found in algae) are necessary for photosynthesis in algae. They have applications in the food industry as natural colourings for food commodities. Carotenoids such as Beta-carotene and fucoxanthin with antioxidant properties can also be extracted from algae.

3. Food: Algae can farm and be eaten unprocessed as vegetables (an example is sea lettuce). As mentioned earlier, lipids which are a particularly important part of our diet can be extracted from algae. Seaweeds produce colloidal polysaccharides which can be employed as thickeners and in confectionery. Dietary supplements like vitamins and iodine are typically sourced from brown seaweeds. Amino acids, carbohydrates and proteins can be produced and harvested in large quantities, packages and reconstituted into food or agricultural feed.

4. Solvents: the alcohols and oils produced are industrial sources of solvents valuable in chemical synthesis.

Common algae species used in biofuel production.

. Botryococcus braunii

. Nanochloris

. Phaeodactylum tricornutum

. Sargassum

. Chorella

. Gracillaria

. Stichococcus

 🔑 Some companies such Solazyme, sapphire energy and Algenol have already begun the commercialization of algae-derived biofuels.

Algae biofuel is a renewable energy source. Due to faster growth rates, biofuels can be produced at faster rates and with higher oil content. While producing cleaner energy by capturing carbon dioxide and curtailing its emissions, they allow for the conservation of resources such as water. Water polluted with industrial chemicals like ammonia and nitrates normally unfit for drinking is the best for algaculture. This prevents pollution of water bodies and eutrophication. Unlike plants, they do not require insecticides or pesticides. Microbes may even be essential in biofuel production. After the extraction of the oils, the green waste can be further decomposed to give biodiesel producing less waste is produced as a result. 

Do you think algae can replace petroleum as a major source of fuel?