Spirulina (dietary supplement)

Spirulina tablets

Spirulina is a cyanobacterium that can be consumed by humans and other animals. There are two species, Arthrospira platensis and Arthrospira maxima.

Arthrospira is cultivated worldwide; used as a dietary supplement as well as a whole food; and is also available in tablet, flake and powder form. It is also used as a feed supplement in the aquaculture, aquarium and poultry industries.[1]

Nutrient and vitamin content

Spirulina（dried）
Nutritional value per 100 g (3.5 oz)
Energy 1,213 kJ (290 kcal)
23.9 g
Sugars 3.1 g
Dietary fiber 3.6 g
7.72 g
Saturated 2.65 g
Monounsaturated 0.675 g
Polyunsaturated 2.08 g
57.47 g
Tryptophan 0.929 g
Threonine 2.97 g
Isoleucine 3.209 g
Leucine 4.947 g
Lysine 3.025 g
Methionine 1.149 g
Cystine 0.662 g
Phenylalanine 2.777 g
Tyrosine 2.584 g
Valine 3.512 g
Arginine 4.147 g
Histidine 1.085 g
Alanine 4.515 g
Aspartic acid 5.793 g
Glutamic acid 8.386 g
Glycine 3.099 g
Proline 2.382 g
Serine 2.998 g
Vitamins
Vitamin A equiv.
beta-carotene
(4%)

29 μg

(3%)
342 μg
0 μg
Thiamine (B1)
(207%)

2.38 mg

Riboflavin (B2)
(306%)

3.67 mg

Niacin (B3)
(85%)

12.82 mg

(70%)

3.48 mg

Vitamin B6
(28%)

0.364 mg

Folate (B9)
(24%)

94 μg

Vitamin B12
(0%)

0 μg

Choline
(13%)

66 mg

Vitamin C
(12%)

10.1 mg

Vitamin D
(0%)

0 IU

Vitamin E
(33%)

5 mg

Vitamin K
(24%)

25.5 μg

Trace metals
Calcium
(12%)

120 mg

Iron
(219%)

28.5 mg

Magnesium
(55%)

195 mg

Manganese
(90%)

1.9 mg

Phosphorus
(17%)

118 mg

Potassium
(29%)

1363 mg

Sodium
(70%)

1048 mg

Zinc
(21%)

2 mg

Other constituents
Water 4.68 g
Percentages are roughly approximated using US recommendations for adults.
Source: USDA Nutrient Database

Protein

Dried spirulina contains about 60% (51–71%) protein.[2][3] It is a complete protein containing all essential amino acids, though with reduced amounts of methionine, cysteine and lysine when compared to the proteins of meat, eggs and milk. It is, however, superior to typical plant protein, such as that from legumes.[2][4][5]

The U.S. National Library of Medicine said that spirulina was no better than milk or meat as a protein source, and was approximately 30 times more expensive per gram.[6]

Other nutrients

Spirulina's lipid content is about 7% by weight,[7] and is rich in gamma-linolenic acid (GLA),[8][9] and also provides alpha-linolenic acid (ALA), linoleic acid (LA), stearidonic acid (SDA),[10] eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA).[5][11] Spirulina contains vitamins B1 (thiamine), B2 (riboflavin), B3 (nicotinamide), B6 (pyridoxine), B9 (folic acid), vitamin C, vitamin A, and vitamin E.[5][11] It is also a source of potassium, calcium, chromium, copper, iron, magnesium, manganese, phosphorus, selenium, sodium, and zinc.[5][11][12] Spirulina contains many pigments which may be beneficial and bioavailable, including beta-carotene,[13] zeaxanthin,[14] 7-hydroxyretinoic acid,[15] isomers, chlorophyll-a, xanthophyll, echinenone, myxoxanthophyll, canthaxanthin, diatoxanthin, 3'-hydroxyechinenone, beta-cryptoxanthin, and oscillaxanthin, plus the phycobiliproteins[16] c-phycocyanin and allophycocyanin.[1]

Vitamin B12 controversy

Spirulina is not considered to be a reliable source of Vitamin B12. Spirulina supplements contain predominantly pseudovitamin B12, which is biologically inactive in humans.[17] Companies which grow and market spirulina have claimed it to be a significant source of B12 on the basis of alternative, unpublished assays, although their claims are not accepted by independent scientific organizations. The American Dietetic Association and Dietitians of Canada in their position paper on vegetarian diets state that spirulina cannot be counted on as a reliable source of active vitamin B12.[18] The medical literature similarly advises that spirulina is unsuitable as a source of B12.[17][19]

Risks

Toxicological studies

Toxicological studies of the effects of spirulina consumption on humans and animals, including feeding as much as 800 mg/kg,[20] and replacing up to 60% of protein intake with spirulina,[21] have shown no toxic effects.[22] Fertility, teratogenicity, peri- and post-natal, and multi-generational studies on animals also have found no adverse effects from spirulina consumption.[23] In a 2009 study, 550 malnourished children were fed up to 10 g/day of spirulina powder, with no adverse effects. Similarly, dozens of clinical studies in humans have shown no harmful effects from spirulina supplementation.

Quality-related safety issues

Spirulina is a form of cyanobacterium, some of which are known to produce toxins such as microcystins, BMAA, and others. Some spirulina supplements have been found to be contaminated with microcystins, albeit at levels below the limit set by the Oregon Health Department.[24] Microcystins can cause gastrointestinal disturbances and, in the long term, liver cancer. The effects of chronic exposure to even very low levels of microcystins are of concern, because of the potential risk of cancer.[24]

These toxic compounds are not produced by spirulina itself,[25] but may occur as a result of contamination of spirulina batches with other toxin-producing blue-green algae. Because spirulina is considered a dietary supplement in the U.S., there is no active, industry-wide regulation of its production and no enforced safety standards for its production or purity.[24] The U.S. National Institutes of Health describes spirulina supplements as "possibly safe", provided they are free of microcystin contamination, but "likely unsafe" (especially for children) if contaminated.[26] Given the lack of regulatory standards in the U.S., some public-health researchers have raised the concern that consumers cannot be certain that spirulina and other blue-green algae supplements are free of contamination.[24]

Heavy-metal contamination of spirulina supplements has also raised concern. The Chinese State Food and Drug Administration reported that lead, mercury, and arsenic contamination was widespread in spirulina supplements marketed in China.[27]

Safety issues for certain target groups

Due to very high Vitamin K content, patients undergoing anticoagulant treatments should not change consumption patterns of spirulina without seeking medical advice to adjust the level of medication accordingly.

Like all protein-rich foods, spirulina contains the essential amino acid phenylalanine (2.6-4.1 g/100 g),[28] which should be avoided by people who have phenylketonuria, a rare genetic disorder that prevents the body from metabolizing phenylalanine, which then builds up in the brain, causing damage.[29]

Etymology and ecology

Main article: Arthrospira

The maxima and plaetensis species were once classified in the genus Spirulina. There is now agreement that they are in fact Arthrospira; nevertheless, and somewhat confusingly, the older term Spirulina remains in use for historical reasons.[1][4]

Arthrospira are free-floating filamentous cyanobacteria characterized by cylindrical, multicellular trichomes in an open left-hand helix. They occur naturally in tropical and subtropical lakes with high pH and high concentrations of carbonate and bicarbonate.[28] Arthrospira platensis occurs in Africa, Asia and South America, whereas Arthrospira maxima is confined to Central America.[1] Most cultivated spirulina is produced in open channel raceway ponds, with paddle-wheels used to agitate the water.[28] The largest commercial producers of spirulina are located in the United States, Thailand, India, Taiwan, China, Bangladesh, Pakistan, Burma (a.k.a. Myanmar), Greece, and Chile.[1]

Spirulina thrives at a pH around 8.5 +, which will get more alkaline, and a temperature around 30 °C (86 °F). They are able to make their own food, and do not need a living energy or organic carbon source. In addition, spirulina have to have an ensemble of nutrients to thrive in a home aquarium or pond. A simple nutrient feed for growing Spirulina is:

which can all be found in aquarium or else in the agricultural division, all commonly occurring compounds except for the iron sulphate. The algae has actually been tested and successfully grown in human urine at 1:180 parts.[30] After 7days, 97% of NH4+-N, 96.5% of total phosphorus (TP) and 85–98% of urea in the urine (ca. 120-diluted) were removed by the microalgae under autotrophic culture (30 °C).[31]

Historical use

Spirulina was a food source for the Aztecs and other Mesoamericans until the 16th century; the harvest from Lake Texcoco and subsequent sale as cakes were described by one of Cortés' soldiers.[32][33] The Aztecs called it "tecuitlatl".[28]

Spirulina was found in abundance at Lake Texcoco by French researchers in the 1960s, but there is no reference to its use by the Aztecs as a daily food source after the 16th century, probably due to the draining of the surrounding lakes for agricultural and urban development.[4][28] The first large-scale spirulina production plant, run by Sosa Texcoco, was established there in the early 1970s.[1]

Spirulina has also been traditionally harvested in Chad. It is dried into cakes called dihé, which are used to make broths for meals, and also sold in markets. The spirulina is harvested from small lakes and ponds around Lake Chad.[34]

Research

At present, research is preliminary. According to the U.S. National Institutes of Health, there is insufficient scientific evidence to recommend spirulina supplementation for any human condition, and more research is needed to clarify its benefits, if any.[26]

It may help in diabetes mellitus.[35]

Advocates

In 1974, the World Health Organization described Spirulina as "an interesting food for multiple reasons, rich in iron and protein, and is able to be administered to children without any risk," considering it "a very suitable food." [36] The United Nations established the Intergovernmental Institution for the use of Micro-algae Spirulina Against Malnutrition in 2003.[37]

In the late 1980s and early 90s, both NASA (CELSS)[38] and the European Space Agency (MELISSA)[39] proposed Spirulina as one of the primary foods to be cultivated during long-term space missions.

See also

Wikimedia Commons has media related to Spirulina.

Notes and references

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Vonshak, A. (ed.). Spirulina platensis (Arthrospira): Physiology, Cell-biology and Biotechnology. London: Taylor & Francis, 1997.
  2. ↑ 2.0 2.1 Khan, Z; Bhadouria, P; Bisen, PS (October 2005). "Nutritional and therapeutic potential of Spirulina.". Current pharmaceutical biotechnology 6 (5): 373–9. PMID 16248810.
  3. ↑ Campanella, L; Russo, MV; Avino, P (April 2002). "Free and total amino acid composition in blue-green algae.". Annali di chimica 92 (4): 343–52. PMID 12073880.
  4. ↑ 4.0 4.1 4.2 Ciferri, O (December 1983). "Spirulina, the edible microorganism". Microbiol. Rev. 47 (4): 551–78. PMC 283708. PMID 6420655.
  5. ↑ 5.0 5.1 5.2 5.3 Babadzhanov, A. S.; Abdusamatova, N.; Yusupova, F. M. et al. (2004). "Chemical Composition of Spirulina Platensis Cultivated in Uzbekistan". Chemistry of Natural Compounds 40 (3): 276–279. doi:10.1023/b:conc.0000039141.98247.e8.
  6. ↑ "Blue-green algae". MedlinePlus. U.S. National Library of Medicine. November 18, 2010. Retrieved April 15, 2011.
  7. ↑ http://www.ejbiotechnology.info/content/vol9/issue4/full/5/
  8. ↑ Colla, LM; Bertolin, TE; Costa, JA (2003). "Fatty acids profile of Spirulina platensis grown under different temperatures and nitrogen concentrations.". Zeitschrift fur Naturforschung. C, Journal of biosciences 59 (1-2): 55–9. PMID 15018053.
  9. ↑ Golmakani, Mohammad-Taghi; Rezaei, Karamatollah; Mazidi, Sara; Razavi, Seyyed Hadi (March 2012). "γ-Linolenic acid production by Arthrospira platensis using different carbon sources". European Journal of Lipid Science and Technology 114 (3): 306–314. doi:10.1002/ejlt.201100264.
  10. ↑ Jubie, S; Ramesh, PN; Dhanabal, P; Kalirajan, R; Muruganantham, N; Antony, AS (August 2012). "Synthesis, antidepressant and antimicrobial activities of some novel stearic acid analogues.". European journal of medicinal chemistry 54: 931–5. PMID 22770606.
  11. ↑ 11.0 11.1 11.2 Tokusoglu, O.; Unal, M.K. "Biomass Nutrient Profiles of Three Microalgae: Spirulina platensis, Chlorella vulgaris, and Isochrisis galbana". Journal of Food Science 68 (4): 2003. doi:10.1111/j.1365-2621.2003.tb09615.x.
  12. ↑ Li, ZY; Guo, SY; Li, L; Cai, MY (February 2007). "Effects of electromagnetic field on the batch cultivation and nutritional composition of Spirulina platensis in an air-lift photobioreactor.". Bioresource technology 98 (3): 700–5. PMID 16581244.
  13. ↑ Dey, S; Rathod, VK (January 2013). "Ultrasound assisted extraction of β-carotene from Spirulina platensis.". Ultrasonics sonochemistry 20 (1): 271–6. PMID 22705076.
  14. ↑ Yu, B; Wang, J; Suter, PM; Russell, RM; Grusak, MA; Wang, Y; Wang, Z; Yin, S; Tang, G (August 2012). "Spirulina is an effective dietary source of zeaxanthin to humans.". The British journal of nutrition 108 (4): 611–9. PMID 22313576.
  15. ↑ Kaya, Kunimitsu; Shiraishi, Fujio; Uchida, Hideaki; Sano, Tomoharu (April 2011). "A novel retinoic acid analogue, 7-hydroxy retinoic acid, isolated from cyanobacteria". Biochimica et Biophysica Acta (BBA) - General Subjects 1810 (4): 414–419. doi:10.1016/j.bbagen.2010.11.009. PMID 21145941.
  16. ↑ Grossman, AR; Schaefer, MR; Chiang, GG; Collier, JL (September 1993). "The phycobilisome, a light-harvesting complex responsive to environmental conditions.". Microbiological reviews 57 (3): 725–49. PMID 8246846.
  17. ↑ 17.0 17.1 Watanabe, F (2007). "Vitamin B12 sources and bioavailability.". Exp. Biol. Med. (Maywood) 232 (10): 1266–74. doi:10.3181/0703-MR-67. PMID 17959839. Most of the edible blue-green algae (cyanobacteria) used for human supplements predominantly contain pseudovitamin B(12), which is inactive in humans. The edible cyanobacteria are not suitable for use as vitamin B(12) sources, especially in vegans.
  18. ↑ Position of the Academy of Nutrition and Dietetics and Dietitians of Canada: Vegetarian diets
  19. ↑ Watanabe, F; Katsura, H; Takenaka, S et al. (1999). "Pseudovitamin B(12) is the predominant cobamide of an algal health food, spirulina tablets.". Journal of Agricultural and Food Chemistry 47 (11): 4736–41. doi:10.1021/jf990541b. PMID 10552882. The results presented here strongly suggest that spirulina tablet algal health food is not suitable for use as a B12 source, especially in vegetarians.
  20. ↑ Krishnakumari, M.K.; Ramesh, H.P.; Venkataraman, L.V. (1981). "Food Safety Evaluation: acute oral and dermal effects of the algae Scenedesmus acutus and Spirulina platensis on albino rats". J. Food Protect. 44 (934).
  21. ↑ Bizzi, A. et al. (1980). Materassi, R., ed. "Trattamenti prolungati nel ratto con diete conntenenti proteine di Spirulina. Aspetti biochimici, morfologici e tossicologici" [Extended Treatment of Rats with Diets Containing Spirulina. Biochemical, morphological, and toxicological aspects.]. Prospettive della coltura di Spirulina in Italia (Accademia dei Geo rgofili, Firence) 205.
  22. ↑ Salazar, M; Martínez, E; Madrigal, E et al. (October 1998). "Subchronic toxicity study in mice fed Spirulina maxima". Journal of Ethnopharmacology 62 (3): 235–41. doi:10.1016/S0378-8741(98)00080-4. PMID 9849634.
  23. ↑ Chamorro-Cevallos, G.; Barron, B.L.; Vasquez-Sanchez, J. (2008). Gershwin, M.E., ed. "Toxicologic Studies and Antitoxic Properties of Spirulina". Spirulina in Human Nutrition and Health (CRC Press).
  24. ↑ 24.0 24.1 24.2 24.3 Gilroy, D.; Kauffman, K.; Hall, D. et al. (2000). "Assessing potential health risks from microcystin toxins in blue-green algae dietary supplements". Environmental Health Perspectives 108 (5): 435–439. doi:10.2307/3454384. JSTOR 3454384. PMC 1638057. PMID 10811570.
  25. ↑ Belay, Amha (2008). "Spirulina (Arthrospira): Production and Quality Assurance". Spirulina in Human Nutrition and Health, CRC Press: 1–25.
  26. ↑ 26.0 26.1 "Blue-green algae". MedlinePlus. National Institutes of Health. July 6, 2011. Retrieved October 4, 2011.
  27. ↑ "China’s drug agency rejects state media claims of cover-up in lead found in health supplement". Washington Post. April 10, 2012. Retrieved April 23, 2012.
  28. ↑ 28.0 28.1 28.2 28.3 28.4 Habib, M. Ahsan B.; Parvin, Mashuda; Huntington, Tim C.; Hasan, Mohammad R. (2008). "A Review on Culture, Production and Use of Spirulina as Food dor Humans and Feeds for Domestic Animals and Fish" (PDF). Food and Agriculture Organization of The United Nations. Retrieved November 20, 2011.
  29. ↑ Robb-Nicholson, C. (2006). "By the way, doctor". Harvard Women's Health Watch 8.
  30. ↑ Feng, DL; Wu, ZC (January 2006). "Culture of Spirulina platensis in human urine for biomass production and O(2) evolution". Journal of Zhejiang University. Science. B 7 (1): 34–7. doi:10.1631/jzus.2006.B0034. PMC 1361757. PMID 16365923.
  31. ↑ Chang, Yuanyuan, et al. "Cultivation of Spirulina platensis for biomass production and nutrient removal from synthetic human urine." Applied Energy 102 (2013) C 427-431. doi:10.1016/j.apenergy.2012.07.024
  32. ↑ Diaz Del Castillo, B. The Discovery and Conquest of Mexico, 1517–1521. London: Routledge, 1928, p. 300.
  33. ↑ Osborne, Ken; Kahn, Charles N. (2005). World History: Societies of the Past. Winnipeg: Portage & Main Press. ISBN 1-55379-045-6.
  34. ↑ Abdulqader, G., Barsanti, L., Tredici, M. "Harvest of Arthrospira platensis from Lake Kossorom (Chad) and its household usage among the Kanembu." Journal of Applied Phycology. 12: 493-498. 2000.
  35. ↑ Kulshreshtha, A.; Zacharia, J.; Jarouliya, U. et al. (2008). "Spirulina in Health Care Management". Current Pharmaceutical Biotechnology 9 (5): 400–405. doi:10.2174/138920108785915111. PMID 18855693.
  36. ↑ "What the United Nations says about Spirulina" (PDF). Spirulina and the Millennium Development Goals. Intergovernmental Institution for the use of Micro-algae Spirulina Against Malnutrition. December 2010. Retrieved 2 July 2014.
  37. ↑ "Charter" (PDF). Intergovernmental Institution for the use of Micro-algae Spirulina Against Malnutrition. 5 March 2003. Retrieved 2 July 2014.
  38. ↑ Characterization of Spirulina biomass for CELSS diet potential. Normal, Al.: Alabama A&M University, 1988.
  39. ↑ Cornet J.F., Dubertret G. "The cyanobacterium Spirulina in the photosynthetic compartment of the MELISSA artificial ecosystem." Workshop on artificial ecological systems, DARA-CNES, Marseille, France, October 24–26, 1990

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