Spirulina (genus)
Spirulina
Spirulina ( Arthrospira correct ) is a genus of cyanobacteria ( formerly known as " blue-green algae ") is. Up to 35 species can be distinguished (for example, Spirulina platensis, Spirulina fusiformis, Spirulina maxima), but it is unclear whether or not these 35 species may yet all belong to the same species as Spirulina their shape depending on the nutrient content and pH of the water changes. Spirulina species is commercially marketed under the name " microalgae " as a dietary supplement.
- 5.1 Nutritional Supplements
- 5.2 Health
Properties
The bacteria form multicellular, spiral microfilaments. Said cylindrical cells have a diameter of about 1 to 5 microns and a length (height) of about 1 to 3 microns. They are arranged one after another in long, right - or left-handed helical filaments with a length of 0.5 mm or more and a coil diameter of 5 to 40 microns. The growth in length of the filaments is associated with cell division, their multiplication is done by disintegration of the filaments.
Spirulina is oxygen photosynthetic and contains only chlorophyll a, which is also present in plants. As spirulina belonging to the prokaryotes, chlorophyll but is not as in the eukaryotic plant cells in organized structures, the chloroplasts, isolated, but is in diaphragms which are distributed over almost the entire cell. Spirulina obtained by other pigments, superimposed on the chlorophyll - green, a green - bluish tint.
Spirulina filaments form ceiling as other filamentous cyanobacteria. As a result of alkalization by consumption of carbon dioxide can be deposited in calcium carbonate. It is believed that in this way the so-called stromatolites arise and have arisen in earlier geological periods. The oldest known stromatolites are found in rock layers that were formed more than three billion years in the Precambrian. This suggests that oxygen - photosynthetic, carbon dioxide - assimilating microorganisms, cyanobacteria may have contributed to the kohlenstoffdioxidreiche primordial Earth's atmosphere with oxygen ( O2) to enrich, to reduce their carbon dioxide content and give it so today's composition.
Occurrence
Spirulina comes in strongly alkaline salt lakes ( pH 9-11 ) before they settled flat, subtropical and tropical waters with high salt content, especially in Central America, Southeast Asia, Africa and Australia. It has been used since ancient times by the people living on these waters for food, for example, of the Kanembu the African Lake Chad in the form of Dihe and the Mexican Lake Texcoco (as Tecuitatl by the Aztecs ). At the last still reminds the Sodakonzentrationsschnecke in the Valley of Mexico.
Cultivation
Spirulina biomass is produced in aquaculture at a water temperature of up to 35 degrees Celsius. The optimal growth of Spirulina depends essentially on the provided amount of carbon dioxide ( CO2). Therefore, the aquaculture, in addition in addition to the CO2 fed to carbon dioxide that passes from the air in the culture from pressurized bottles. So Spirulina grows not only faster but also produces much more oxygen. Harvesting the culture is pumped through a filter, or a continuous flow centrifuge, followed by drying the so obtained biomass, with hot air. The dried biomass is usually pressed for distribution to tablets, enclosed in capsules or powdered.
Ingredients
The dry preparations contain on average:
- 59.78 % of proteins
- 20.2 % carbohydrate
- 4.06% fats
- 5.47% minerals
All essential amino acids in the proteins are included. In addition, β -carotene - a precursor of vitamin A -, B- vitamins, and vitamin E, and containing high concentrations of calcium, iron and magnesium.
Vitamin B12
Spirulina contains - relative to the analytically determined high overall value - about 80% an ineffective form of the vitamin ( "pseudo vitamin B12 ", " B12 analogs" ), at about 20 % is the usable human- vitamin form. This ratio of usable vitamin and so-called analogues found in many, even animal foods, so it is not unique to Spirulina. A purely theoretical consideration shows that it is possible that an excess of analogues can block the uptake and metabolism of physiological vitamin B12; proved this theory is neither experiments nor by patient studies. Studies in 1991 and 1999 with children who had a vitamin B12 deficiency, showed that after administration of Spirulina Although the blood levels rise to measurable Cyanocobalaminen symptoms of disease but not disappeared.
Microcystin
One problem is the contamination is with carcinogenic microcystins, can damage the liver, kidney and brain. Commercially available products that ( AFA Aphanizomenon flos -aquae for a cyanobacterium ) were prepared from the "Green Spanalge " that contain a hazardous substance. If the bacterium is not cultured in separate sealed tank, but is harvested from open lakes, there is the risk that toxic algae or cyanobacteria contaminate the preparations. Manufacturers must counteract accordance with quality assurance in the breeding and processing here.
Use
About 3000 tons gross weight Spirulina platensis are sold from commercial cultivation as a dietary supplement every year. Spirulina is available as a dietary supplement in Germany as well as the freshwater alga Chlorella in the form of powder or tablets and is in ( bio) food processed as nutrient-rich ingredient (pasta, fruit bars, powdered drinks, etc.). Spirulina is also a component of many fish food and some cat foodstuff. Other uses are found in the biotechnology and bioengineering, where Spirulina is used among other things as a biocatalyst in fermentation processes and for energy.
Nutritional Supplements
In Spirulina products as dietary supplements of protein content and vitamin B12 content is awarded. However, the dose is absorbed from food supplements when taking the maximum recommended dose is so low that it makes the additional protein intake is hardly noticeable in the rule. The sometimes separately excellent chlorophyll found in every food with green plant parts. Touting of vitamin B12 is considered misleading advertising.
The European Food Safety Authority came after analysis of the studies submitted by manufacturers to the conclusion that spirulina capsules have no effect on the glucose concentration in the blood of diabetics. According to the Health Claims Regulation dietary supplements should not be promoted in this respect.
Health
In the alternative medicine Spirulinapräparaten said to have potential effects against cancer, viruses, and allergies.
The application of Spirulina preparations may lower the cholesterol concentration in the blood. In the studies carried out, however, were only minor effects to days, the numbers of subjects in the studies were too small or the study design bad so far present some useful results.
Has also been documented immunomodulatory effect of spirulina among others with allergies as mast cell inhibitor - Spirulina inhibits the release of histamine from mast cells. Ishii et al. demonstrated the positive effect of Spirulina on the immunoglobulin A secretion and thereby improving immune competence and host defense in saliva. A more recent double-blind placebo-controlled study in Turkey occupies a significant efficiency of Spirulina in the treatment of patients with allergic rhinitis. If well tolerated, the symptoms including amount of secretion, sneezing, swollen mucous membranes and itching were significantly improved. In another randomized, double- blind, placebo-controlled study, subjects took 12 weeks daily 1 g or 2 g of spirulina. It was found that the levels of interleukin-4, which plays a role in reinforcing the immunoglobulin E -mediated allergy, by about 32% could be reduced. In addition, an anti -viral activity of Spirulina against the Epstein -Barr virus in a study of 2011 could be detected. A meta- analysis suggested a positive effect on various parameters, however, criticized the existing studies to 2008 as of poor methodological quality and insufficient for assessment.