Medicinal Uses of Red Algae and Blue-Green Algae
Niha Naveed
First Year BDS, Saveetha Dental College and Hospitals, Chennai
*Corresponding Author E-mail:
ABSTRACT:
Red algae have been used as a traditional medicine for centuries. Medical science has identified a number of complex carbohydrates with unique chemical properties. For instance, certain algal extracts have antiviral and anti-tumour properties. The high fibre content of red algae means it is also useful in improving digestion. Red algae are frequently taken as a dietary supplement, though its status as a "super-food" is uncertain since it hasn't been shown to improve normal function. Blue-green algae are used as a source of dietary protein, B-vitamins, and iron. They are also used for weight loss, attention deficit-hyperactivity disorder (ADHD), hay fever, diabetes, stress, fatigue, anxiety, depression, and premenstrual syndrome (PMS) and other women’s health issues. Some people use blue-green algae for treating precancerous growths inside the mouth, boosting the immune system, improving memory, increasing energy and metabolism, lowering cholesterol, preventing heart disease, healing wounds, and improving digestion and bowel health.
KEYWORDS: Antioxidants, immunomodulatory, superfoods, proteins, metabolism.
INTRODUCTION:
Today's scientists are only beginning to grasp the incredible nutritional value of blue-green algae and red algae, but these superfoods have a reputation that reaches far back into history. A form of blue-green algae was consumed regularly hundreds of years ago by Aztecs. Today blue-green algae and redalgae are some of the top superfoods, providing extraordinary nutrition in a time when most food sources are of poor nutritional quality.They are natural foods that have existed since life began. Their nutritional content is broad and highly concentrated. These algae have been lab tested in vitro (glass contained specimens) or in vivo (live mammals) for many health issues often with astonishing positive results.
Red algae:
Taxonomy1
Kingdom: Plantae or Protista
Division: Rhodophyta
Class: Florideophycidae
Order: Halymeniales
Family: Halymeniaceae
Genus: Prionitis
Species: lanceolata
Description:
Phylum Rhodophyta of the kingdom protista consist of the photosynthetic organisms commonly known as red algae. Members of the division have a characteristic clear red or purplish color imparted by accessory pigments called phycobilins. In general algae can be referred to as plant-like organisms that are usually photosynthetic and aquatic, but do not have true roots, stems, leaves, vascular tissue and have simple reproductive structures. The red algae are multicellular and are characterized by a great deal of branching, but without differentiation into complex tissues. Most of the world's seaweeds belong to this group2. Although red algae are found in all oceans, they are most common in warm-temperate and tropical climates, where they may occur at greater depths than any other photosynthetic organisms. Most of the coralline algae, which secrete calcium carbonate and play a major role in building reefs, belong here. Red algae are a traditional part of oriental cuisine. There are 4000 known marine species of red algae; a few species occur in freshwater3.
Distinguishing characteristics:
Red algae have a number of general characteristics that in combination distinguish them from other eukaryotic groups4:
· Absence of flagella and centrioles
· Floridean starch as a storage product and the storage of starch in the cytoplasm
· Phycoerythrin, phycocyanin, and allophycocyanin as accessory pigments
· Unstacked thylakoids in plastids
· No chloroplast endoplasmic reticulum
Ecology:
There are more than 5200 species of rhodophytes, and although some rhodophytes do inhabit fresh water, red algae are most common in tropical marine environments. The various red algae have a complicated life history, often involving three stages of independent organisms to complete their life cycle. The elucidation of this life cycle has been very important for the billion-dollar nori industry of Japan. This is a large assemblage of between 2500 and 6000 species in about 670 largely marine genera that predominate along the coastal and continental shelf areas of tropical, temperate and cold-water regions5. Red Algae are ecologically significant as primary producers, providers of structural habitat for other marine organisms, and their important role in the primary establishment and maintenance of coral reefs. Among the algae that can invade freshwater ponds and aquaria, red algae from the division Rhytophyta, can be the most frustrating. This furry, thread-like flora attaches to various aquarium surfaces including the edges of plant leaves, filter tubes and even gravel. Some rhodophytes are also important in the formation of tropical reefs, an activity with which they have been involved for millions of years; in some Pacific atolls, red algae have contributed far more to reef structure than other organisms, even more than corals6.
Medicinal uses:
One benefit of red marine algae is its antioxidant effect, which counters damage free radicals do to cells. Red marine algae is also an anti-viral compound. The carrageenans -- a type of sugar molecule -- found in red marine algae are believed to boost interferon production in the immune system and might be an effective preventative against diseases like HIV, shingles and cold sores7. Natural antioxidants, found in many algae, are important bioactive compounds that play an important role against various diseases and ageing processes through protection of cells from oxidative damage. It helps in the chemoprevention of a variety of diseases including cancer. Marine algae produce a diverse array of compounds that function as chemical defense systems facilitating their survival in extremely competitive environments. Red algae have been suggested as a promising source of bioactive substances that might have pharmaceutical applications. Marine algae in shallow water habitats can be exposed to a combination of ultraviolet light and air that readily leads to the formation of free radicals and other reactive oxygen species (ROS)8. Despite their exposure to harmful ROS, healthy algae lack oxidative damage in their structural components and resist oxidation during storage, indicating the presence of protective antioxidant defense systems in their cells. By donating an electron, antioxidants neutralize free radicals that would otherwise oxidize biomolecules leading to cell death and tissue damage. Accordingly, interest in the search for natural antioxidants from algae has been increasing in recent years. The overall aim of this type of research is discovery of compounds or extracts that can counteract free radical-induced and other oxidative stress processes, and in so doing decrease the incidence of human diseases directly related to these processes. Antioxidant activity has been reported in numerous genera of marine algae, including Ahnfeltiopsis, Colpomenia, Gracilaria, Halymenia Hydroclathrus, Laurencia, Padina, Polysiphonia, and Turbinaria9.Natural antioxidants from algae are known to play an important role against various diseases and aging processes. The detected antioxidant compounds in algae from these genera and others have potential anti-aging, dietary, anti-inflammatory, antibacterial, antifungal, cytotoxic, anti-malarial, anti-proliferative, and anticancer properties. In the Hawaiian Islands there are approximately 520 reported species of marine algae, very few of which have been investigated biochemically in any way. In one of the few systematic studies, McDermid and Stuercke reported on the nutritional composition of 22 species of Hawaiian algae, testing for protein, lipid, carbohydrate, ash, caloric, mineral, and vitamin content10. The red algal extracts also showed antimicrobial activity. Beyond this finding, there is no published information on the antioxidant activity of Hawaiian algae. It is expected that additional Hawaiian algae contain very effective antioxidant systems, as they are exposed to prolonged intense ultraviolet (UV) radiation in their tropical environment. In fact, it has been observed that UV radiation stimulates antioxidant defense in algae.11,12
Blue-Green Algae:
Taxonomy13
Division: Cyanophyta (Cyanobacteria)
Class: Nostocophyceae (Cyanophyceae)
Order: Nostocales
Characteristics:
The algae are the simplest members of the plant kingdom, and the blue-green algae are the simplest of the algae. They have a considerable and increasing economic importance; they have both beneficial and harmful effects on human life. Blue-greens are not true algae. They have no nucleus, the structure that encloses the DNA, and no chloroplast, the structure that encloses the photosynthetic membranes, the structures that are evident in photosynthetic true algae. In fact blue-greens are more akin to bacteria which have similar biochemical and structural characteristics14. The process of nitrogen fixation and the occurrence of gas vesicles are especially important to the success of nuisance species of blue-greens. The blue-greens are widely distributed over land and water, often in environments where no other vegetation can exist. Their fossils have been identified as over three billion years old. They were probably the chief primary producers of organic matter and the first organisms to release elemental oxygen, O2, into the primitive atmosphere, which was until then free from O2. Thus blue-greens were most probably responsible for a major evolutionary transformation leading to the development of aerobic metabolism and to the subsequent rise of higher plant and animal forms. They are referred to in literature by various names, chief among which are Cyanophyta, Myxophyta, Cyanochloronta, Cyanobacteria, blue-green algae, blue-green bacteria15.
Uniqueness of blue-green algae:
The majority of blue-greens are aerobic photoautotrophs: their life processes require only oxygen, light and inorganic substances. A species of Oscillatoria that is found in mud at the bottom of the Thames, are able to live anaerobically. They can live in extremes of temperatures -60°C to 85°C, and a few species are halophilic or salt tolerant (as high as 27%, for comparison, conc. of salt in seawater is 3%) 16. Blue-greens can grow in full sunlight and in almost complete darkness. They are often the first plants to colonize bare areas of rock and soil, as an example subsequent to cataclysmic volcanic explosion (at Krakatoa, Indonesia in 1883)17. Unlike more advanced organisms, these need no substances that have been performed by other organisms. At the onset of nitrogen limitation during bloom conditions, certain cells in Anabaena and Aphanizomenon evolve into heterocysts, which convert nitrogen gas into ammonium, which is then distributed to the neighboring cells of a filament. In addition, blue-greens that form symbiotic (mutually beneficial) relationships with a wide range of other life forms, can convert nitrogen gas into ammonium.Finally, at the onset of adverse environmental conditions, some blue-greens can develop a modified cell, called an akinete. Akinetes contain large reserves of carbohydrates, and owing to their density and lack of gas vesicles, eventually settle to the lake bottom. They can tolerate adverse conditions such as the complete drying of a pond or the cold winter temperatures, and, as a consequence, akinetes serve as "seeds" for the growth of juvenile filaments when favorable conditions return. Heterocysts and akinetes are unique to the blue-greens18.
Ecology:
Blue-greens in fresh water lakes:
Unicellular and filamentous blue-greens are almost invariably present in freshwater lakes frequently forming dense planktonic populations or water blooms in eutrophic (nutrient rich) waters. In temperate lakes there is a characteristic seasonal succession of the bloom-forming species, due apparently to their differing responses to the physical- chemical conditions created by thermal stratification. Usually the filamentous forms (Anabaena species, Aphanizomenon flos-aquae and Gloeotrichia echinulata) develop first soon after the onset of stratification in late spring or early summer, while the unicellular-colonial forms (like Microcystis species) typically bloom in mid-summer or in autumn. The main factors which appear to determine the development of planktonic populations are light, temperature, pH, nutrient concentrations and the presence of organic solutes19.
Attached and benthic population in lakes:
Many blue-greens grow attached on the surface of rocks and stones (epilithic forms), on submerged plants (epiphytic forms) or on the bottom sediments (epipelic forms, or the benthos) of lakes. The epilithic community displays a clearly discernable zonation in lakes. Members of the genera Pleurocapsa, Gloeocapsa and Phormidium often dominate the dark blue-black community of the spray zone. Scytonema and Nostoc species form olive-green coatings and are more frequent about the water line, whilst the brownish Tolypothrix and Calothrix species are more typical components of the subsurface littoral community.The epiphytic flora of lakes is usually dominated by diatoms and green algae, and blue-greens are of less importance in this community. Species of the genera Nostoc, Lyngbya, Chamaesiphon and Gloeotrichia have been occasionally encrusting submerged plants. The epipelic community commonly includes blue-greens like Aphanothece and Nostoc particularly in the more eutrophic lakes. Benthic blue-greens growing over the littoral sediments and on submerged plants may be responsible for the occasional high rates of N2-fixation measured in oligotrophic lakes19.
Terrestrial blue-greens:
In the temperate region blue-greens are especially common in calcareous and alkaline soils. Certain species, Nostoc commune, are often conspicuous on the soil surface. Acid soils, however, lack blue-green element and are usually dominated by diatoms and green algae19.
Dietary supplementation and health benefits:
The blue green algae spirulina is a good source of protein, with about 6 grams in each 100-gram serving. Its protein content includes all the essential amino acids, making it a complete source of these important nutrients. A 100-gram serving also contains about 2 grams of carbohydrates and almost no fat20. With only 26 calories in each serving, spirulina is a naturally low-calorie food. It also provides modest amounts of several important minerals, including calcium, iron, potassium and magnesium, as well as small amounts of zinc and phosphorus. The algae also contain vitamins A, C, E and several of the B vitamins, including thiamin, riboflavin, vitamin B-6 and folate21. Microalgae contain substances of high biological value, such as polyunsaturated fatty acids, amino acids (proteins), pigments, antioxidants, vitamins and minerals. Edible blue-green algae reduce the production of pro-inflammatory cytokines by inhibiting NF-κB pathway in macrophages and splenocytes. Consumption of edible blue green algae may also reduce risks of cataracts and age related macular degeneration.15, 22. It has also shown mitigative effects in animal models of non-alcohol related liver disease, such as steatohepatitis and Parkinson's disease. Sulfate polysaccharides exhibit immune modulatory, antitumor, antithrombotic, anticoagulant, anti-mutagenic, anti-inflammatory, antimicrobial, and even antiviral activity against HIV, herpes, and hepatitis. They also improve insulin resistance in HIV23. They also protect against aflatoxin and cisplatin chemotherapy induced liver damage. These positive health benefits must be distinguished from non-edible species of algae, which are detrimental to health. Blue green algae may boost your immune system and have natural anti-viral properties, helping suppress growth of HIV and other viruses. Consuming blue green algae may also help relieve fatigue and improve your tolerance of exercise. It was found that male subjects who consumed spirulina for four weeks were able to exercise longer and had changes in their blood that indicated better usage of nutrients compared to a placebo group. Blue green algae may also lower blood cholesterol levels and reduce blood pressure, according to a study published in "Nutritional Research and Practice" in which 37 subjects with Type 2 diabetes had improved blood lipids and lower blood pressure after taking spirulina for 12 weeks.24,25.
CONCLUSION:
Red marine algae have been used for a variety of purposes in Asia for more years than have been recorded. Originally probably, used as a food, it then found many medicinal applications for a wide variety of conditions depending upon the species of algae. In fact, one of the earliest written records from China dating to 600 BC mentions algae as being a food suitable for a king. Red algae is also used in a variety of other ways, and research continues on the benefits of algae for medicine. Some claims about algae include the ability of red algae to improve our immune system, treat respiratory ailments and skin problems, and cure cold sores. Algae also contains abundant amounts of Iodine, an element required by humans and necessary for proper thyroid functioning. The other uses include treatment for cancer and for treating goiters, testicular pain and swelling, edema, urinary infections and sore throat. Blue-green algae is a nutrient- and antioxidant-rich plant group that is used as a food, nutritional supplement and alternative medicinal supplement. Little scientific research has been conducted on blue-green algae using human subjects, but animal and laboratory studies have hinted that the plant might be beneficial in treating several different conditions. Blue-green algae typically comes in the form of tablets and is taken in doses of 500 milligrams four to six times daily. Organic blue-green algae is one of the most nutrient dense foods on the planet. Two varieties, spirulina and Aphanizomenonflos-aquae, are the most consumed forms of blue green algae; which has super food status due to high concentrations of proteins, vitamins and nutrients.
REFERENCES:
1. The Seaweed Site; Rodophyta: Red Algae; M.D. Guiry; 2011
3. Garbary, D.J. &Gabrielson, P.W. 1990. Taxonomy and evolution. Pages 477-498 in Biology of the red algae (K.M. Cole and R.G. Sheath, eds.). Cambridge University Press, Cambridge.
4. Lüning, K. 1990. Seaweeds: Their environment, biogeography, and ecophysiology. Wiley, New York.
5. Ragan, M.A., C.J. Bird, E.L. Rice, R.R. Gutell, C.A. Murphy and R.K. Singh. 1994. A molecular phylogeny of the marine red algae (Rhodophyta) based on the nuclear small-subunit rRNA gene. Proc. Natl. Acad. Sci. USA 91:7276-7280.
6. Woelkerling, W.J. 1990. An introduction. Pages 1-6 in Biology of the red algae (K.M. Cole and R.G. Sheath, eds.). Cambridge University Press, Cambridge.
7. Cardozo K.H.M., Guaratini T., Barros M.P., Falcao V.R., Tonon A.P., Lopes N.P., Campos S., Torres M.A., Souza A.O., Colepicolo P., et al. Review: Metabolites from algae with economical impact. Comp. Biochem. Physiol. C. 2007;146:60–78.PubMed
8. Faulkner D.J. Marine natural products. Nat. Prod. Rep.2002; 19:1–49. PubMed
9. Blunt J.W., Copp B.R., Munro M.H., Northcote P.T., Prinsep M.R. Marine natural products. Nat. Prod. Rep. 2011; 28:196–268.PubMed
10. Smit A.J. Medicinal and pharmaceutical uses of seaweed natural products: A review. J. Appl. Phycol. 2004; 16:245–262.
11. Mallick N., Mohn F.H. Reactive oxygen species: Response of algal cells. J. Plant Physiol. 2000; 157:183–193.
12. Matanjun P., Mohamed S., Mustapha N.M., Muhammad K., Ming C.H. Antioxidant activities and phenolics content of eight species of seaweeds from north Borneo. J. Appl. Phycol.2008;20:367–373.
13. "A proposal for further integration of the cyanobacteria under the Bacteriological Code". Int. J. Syst. Evol. Microbiol. 54 (Pt 5): 1895–1902.
14. "Life History and Ecology of Cyanobacteria". University of California Museum of Paleontology. Retrieved 17 July 2012.
15. Nadis, Steve (November 2003). "The Cells That Rule the Seas". Scientific American.
16. Ku, C. S.; Pham, T. X.; Park, Y.; Kim, B.; Shin, M.; Kang, I.; Lee, J. (2013). "Edible blue-green algae reduce the production of pro-inflammatory cytokines by inhibiting NF-κB pathway in macrophages and splenocytes". Biochimica et Biophysica Acta (BBA) - General Subjects.
17. Simple conditions for growth of unicellular blue-green algae on plates; Mary Mennes Allen; Journal of PhycologyVolume 4, Issue 1, pages 1–4,March 1968.
18. Allen MM, Stanier RY. Growth and division of some unicellular blue-green algae. J Gen Microbiol. 1968 Apr;51(2):199–202. PubMed
19. Horton AA. NADH oxidase in blue-green algae. Biochem Biophys Res Commun. 1968 Sep 6;32(5):839–845. PubMed
20. Stanier RY, Van Niel CB. The concept of a bacterium. Arch Mikrobiol. 1962;42:17–35.PubMed
22. WA Kratz, J Myers - American Journal of Botany, 1955 - JSTOR
24. RN Singh - Role of blue-green algae in nitrogen economy of Indian, 1961
26. “Antioxidant and anti-inflammatory properties of C-phycocyanin from blue-green algae”, Inflammation Research, January 1998, Volume 47, Issue 1, pp 36-41
Received on 11.09.2014 Modified on 16.09.2014
Accepted on 19.09.2014 © RJPT All right reserved
Research J. Pharm. and Tech. 7(12): Dec. 2014; Page 1472-1475