''Arthrospira platensis'' is a filamentous,

gram-negative Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall ...

cyanobacterium Cyanobacteria (), also known as Cyanophyta, are a phylum of gram-negative bacteria that obtain energy via photosynthesis. The name ''cyanobacteria'' refers to their color (), which similarly forms the basis of cyanobacteria's common name, blue ...

. This bacterium is non-nitrogen-fixing photoautotroph. It has been isolated in Chenghai Lake, China,

soda lake A soda lake or alkaline lake is a lake on the strongly alkaline side of neutrality, typically with a pH value between 9 and 12. They are characterized by high concentrations of carbonate salts, typically sodium carbonate (and related salt compl ...

s of East Africa, and subtropical,

alkaline lake A soda lake or alkaline lake is a lake on the strongly alkaline side of neutrality, typically with a pH value between 9 and 12. They are characterized by high concentrations of carbonate salts, typically sodium carbonate (and related salt complex ...

Morphology

''Arthrospira platensis'' is filamentous, motile bacterium. Motility has been described as a vigorous gliding without a visible flagella.

Metabolism

As a photoautotroph the major carbon source is carbon dioxide and water is a source of electrons to perform CO₂ reduction.

Genetics

''Arthrospira platensis'' has a single circular chromosome containing 6.8 Mb and 6,631 genes. The G+C content has been determined to be 44.3%.

Growth conditions

''Arthrospira platensis'' has been found in environments with high concentrations of carbonate and bicarbonate. It can also be found in high salt concentrations because of its alkali and salt tolerance. The temperature optimum for this organism is around 35 °C. Based on environmental conditions, culture medium often has a pH between 9-10, inorganic salts, and a high bicarbonate concentration.

Uses

There are various present and past uses of ''A. platensis'' as food or

food supplement A dietary supplement is a manufactured product intended to supplement one's diet by taking a pill, capsule, tablet, powder, or liquid. A supplement can provide nutrients either extracted from food sources or that are synthetic in order ...

, which is better known as ' Spirulina' in this context. Spirulina is sold as a health supplement in the form of powder or tablets due to its high levels of essential and

unsaturated fatty acids In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food. The term often refers specifically to triglycerides (trip ...

vitamins A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient that an organism needs in small quantities for the proper functioning of its metabolism. Essential nut ...

dietary minerals In the context of nutrition, a mineral is a chemical element required as an essential nutrient by organisms to perform functions necessary for life. However, the four major structural elements in the human body by weight ( oxygen, hydrogen, ca ...

, and

antioxidants Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubricants, ...

. After the

Chernobyl disaster The Chernobyl disaster was a nuclear accident that occurred on 26 April 1986 at the No. 4 reactor in the Chernobyl Nuclear Power Plant, near the city of Pripyat in the north of the Ukrainian SSR in the Soviet Union. It is one of only two nuc ...

, Spirulina was given to victims due to its

antioxidant Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubric ...

properties to avoid adverse effects of

reactive oxygen species In chemistry, reactive oxygen species (ROS) are highly reactive chemicals formed from diatomic oxygen (). Examples of ROS include peroxides, superoxide, hydroxyl radical, singlet oxygen, and alpha-oxygen. The reduction of molecular oxygen () ...

. Proteins extracted from ''A. platensis'' can be used in food as thickening agents or stabilizers of

emulsions An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although ...

or foams. The light-harvesting complex of ''A. platensis'', phycocyanin, can be extracted as a blue pigment powder and used as blue colorant in food. As ''A. platensis'' cells contain

hydrogenase A hydrogenase is an enzyme that catalyses the reversible oxidation of molecular hydrogen (H2), as shown below: Hydrogen uptake () is coupled to the reduction of electron acceptors such as oxygen, nitrate, sulfate, carbon dioxide (), and fumar ...

s and can produce

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxi ...

, they are a candidate for the production of

renewable energy Renewable energy is energy that is collected from renewable resources that are naturally replenished on a human timescale. It includes sources such as sunlight, wind, the movement of water, and geothermal heat. Although most renewable ener ...

References

{{Taxonbar, from=Q17189730 Oscillatoriales