Many of our friends despise algae by calling them pond scum, seaweeds, and even frog spittle! But the fact is that it is the algae that give us the air we breathe, the food we eat, and the fuel for our cars (past and, perhaps, future), are also a source of active pharmaceutical compounds that can be used against drug-resistant bacterial strains, viruses (including Herpes Simplex and AIDS), and cancers. No other groups of “plants” have done so much, for so long, and, for so many as have the algae!
Algae normally are scoffed at!!!!
Indeed many people only experience algae in “bad situations” such as a big problem in local lakes, fishing holes, or even personal swimming pools, or as insect-covered seaweed litter on the beach or as contaminants in tropical fish tanks, or even worse, as red tides poisoning our seafood and/or us. In the English language, the common terms for algae include “pond scum,” “seaweeds,” “rockweed,” “ bladder wrack,” “sea wrack” and, even “frog spittle.” But we owe our life to algae
Benefits of Algae
1. Algae were the organisms which by producing oxygen first in earth’s atmosphere and paved way for survival of living organisms, thus paving the way for the evolution of eukaryotic organisms. Today, the production of oxygen by algae (ca. 50% of all oxygen production) is another reason for saying “our lives depend on algae.” Given that the total biomass of the world’s algae is but a tenth of the biomass of all the other plants, the efficiency of the algae is impressive
Some 3.5 billion years ago prokaryotic life began on the planet in the absence of oxygen. The cyanobacteria (blue–green algae) arose and began releasing oxygen into the atmosphere as the waste product of chlorophyll a-mediated photosynthesis. Iron and other metals in surface rocks oxidized and consumed oxygen and the massive ocean absorbed oxygen for a billion years and therefore, the levels of oxygen did not rise significantly. But about 2.45 billion years ago the level of oxygen in the atmosphere began to rise because the exposed minerals were fully oxidized and absorption by the oxygen-enriched upper layers of the ocean abated (Kump 2008). Oxygen levels rose and the evolution of eukaryotic organisms began, giving rise along the way to humans (for better or worse). Remember we need 21% oxygen in atmosphere to survive.
2 The crude oil (petroleum) comes mostly from Cretaceous deposits of marine algae.
Pristane (2, 6, 10, 16-tetramethyl pentadecane), which amounts to 0.5% (of East Texas) or 0.2% of (Mid-Continent) oils, is believed to be a derivative of phytol, a terpenoid component of chlorophyll molecule. It is assumed that phytol (C20) on decarboxylation gives rise to pristane (C19). It is suggested that isoprenoids like carotenes undergo low temperature reactions to produce napthenic and aromatic hydrocarbons similar to those of petroleum (Erdman, 1961, McMarry and Thornton, 1952). The abundance of carotenoids in many of the marine algae like brown algae which constitute the major share of ocean flora correlates well with this idea of carotenes giving rise to naphthenes and some aromatics.
3. Seafood Those who love seafood should thank the algae because algae are the primary producers upon which aquatic ecosystems depend. The high plankton production in coastal zones, primary productivity that is passed to higher trophic levels where it is more availableThe large forests of Brown and Red Algae support or shelter a wealth of shellfish, fish, marine mammals, seabirds, and seaweeds, resources heavily used historically by coastal peoples.(Please read my story on “Kelp Highway” of 8t April, 2022)
4. Sustainable biofuel production and CO2 consumption. Oleaginous microalgae are attractive cell factories for the production of third-generation biofuels due to their ability to achieve an outstanding accumulation of lipids, in some cases surpassing 20% of total biomass in dry weight and reaching economic feasibility. Some studies have reported microalgae lipid productivities around 136,900 L ha−1 year−1 , which are several times higher than those achieved by oil palm plantations (22,780 L ha−1 year−1). Microalgae have also been explored for the production of non-lipid-based biofuels. Several genera of microalgae have been used for biofuel production, and metabolic models now exist for organisms such as Chlamydomonas , Chlorella , Nannochloropsis , Synechocystis , Tetraselmis , Monoraphidium , Ostreococcus , Tisochrysis , and Phaeodactylum . The genetic tractability of several microalgae (Chlamydomonas, Synechocystis, Phaeodactylum) also renders them interesting for gene-knockout studies using metabolic modeling tools.
Another very promising candidate is Botryococcus braunii This fresh water green colonial microalga belonging to Chlorococcales, inhabiting freshwater ponds and lakes, has the peculiar ability to synthesize hydrocarbons in large quantities. It is known to be a rich source of lipids including fatty acids, epoxides, alkylphenols, ether lipids and also hydrocarbons sometimes in very high amount (Metzger et al. 1991). The algal scum occurring near southern Australia and Soviet Kazakhstan contains upto 70% hydrocarbons very similar to crude petroleum. In the intact cell, the hydrocarbons occur mostly (upto 95%) in the cell walls and have carbon number C25-C31. The location of hydrocarbons in the outer cell makes the recovery of hydrocarbons easy. According to the type of hydrocarbons produced 3 chemotypes are recognized (1) A-race producing odd carbon numbered n–alkadienes and trienes (2) B-race, producing CnH2n–10triterpenes (n=30-37) called botyrococcenes and (3) L-race yielding an acyclic tretraterpene, trans, trans, lycopadiene. In addition to botyrococcenes, the B-race produces small amount of squalenes and methylated squalenes. Unusual carotenoids with a tetramethyl squalene skeleton and C31 – C34 methylated squalenes also are reported from B-race (Achitouv, et al., 2004). This alga is very slow growing and measures are in progress to increase its rate of growth (Largeau, et. al., 1980).
Please see my story on “Charismatic Carbon” which appeared on 19th April, 2022 for the role of Algae in fixing atmospheric carbon.
5. Algae are now the sources of a Large number of new Antimicrobials, Antivirals, Therapeutic proteins, drugs, Antifungals and many more. Some of the active compounds are polyphenols, phycobiliproteins and vitamins. Antioxidants help in the inhibition of cancer growth by causing regression of premalignant lesions. Below are some examples:-
• Enteromorpha: It can be used to treat hemorrhoids, parasitic disease, goiter, coughing and bronchitis; fever reducyion capacity and ease pain.
• Acetabularia: This can be used to treat urinary diseases and edema.
• Laminaria: It can be used for thyroid problems and urinary diseases.
• Sargassum: It can be used to treat cervical lymphadenitis, edema; diminishes inflammation; induces urination; contains both iodine and potassium
• Gelidium: can be used to extract agar
• Corallina: It can be used as pesticides
• Grateloupia: Blood sugar lowing capability
• Gloeopeltis: Treatment for tonsils, goitre.
Mammen Daniel
