Arthrospira platensis is a filamentous, gram-negative cyanobacterium. This bacterium is non-nitrogen-fixing photoautotroph.[1] It has been isolated in Chenghai Lake, China, soda lakes of East Africa, and subtropical, alkaline lakes.[2][3][4]

Arthrospira platensis
A single Spirulina ("Arthrospira platensis") colony
A single Arthrospira platensis colony
Scientific classification Edit this classification
Domain: Bacteria
Phylum: Cyanobacteria
Class: Cyanophyceae
Order: Oscillatoriales
Family: Microcoleaceae
Genus: Arthrospira
Species:
A. platensis
Binomial name
Arthrospira platensis
Gomont

Morphology

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Arthrospira platensis is filamentous, motile bacterium. Motility has been described as a vigorous gliding without a visible flagella.[1]

Metabolism

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

Genetics

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Arthrospira platensis has a single circular chromosome containing 6.8 Mb and 6,631 genes.[1] The G+C content has been determined to be 44.3%.[1]

Growth conditions

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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.[2] Based on environmental conditions, culture medium often has a pH between 9-10, inorganic salts, and a high bicarbonate concentration.[2]

Uses

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There are various present and past uses of A. platensis as food or food supplement, 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, vitamins, dietary minerals, and antioxidants.[5] After the Chernobyl disaster, Spirulina was given to victims due to its antioxidant properties to avoid adverse effects of reactive oxygen species.[6] Proteins extracted from A. platensis can be used in food as thickening agents[7] or stabilizers for emulsions[8] or foams.[9] A direct comparison indicates that A. platensis protein isolates are more effective at reducing surface tension compared to commonly used animal proteins.[10] The light-harvesting complex of A. platensis, phycocyanin, can be extracted as a blue pigment powder and used as blue colorant in food.[11] As A. platensis cells contain hydrogenases and can produce hydrogen, they are a candidate for the production of renewable energy.[12]

References

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  1. ^ a b c d Fujisawa T, Narikawa R, Okamoto S, Ehira S, Yoshimura H, Suzuki I, et al. (April 2010). "Genomic structure of an economically important cyanobacterium, Arthrospira (Spirulina) platensis NIES-39". DNA Research. 17 (2): 85–103. doi:10.1093/dnares/dsq004. PMC 2853384. PMID 20203057.
  2. ^ a b c Masojídek J, Torzillo G (2008). "Mass Cultivation of Freshwater Microalgae". Encyclopedia of Ecology. Elsevier. pp. 2226–2235. doi:10.1016/b978-008045405-4.00830-2. ISBN 9780080454054.
  3. ^ Xu T, Qin S, Hu Y, Song Z, Ying J, Li P, et al. (August 2016). "Whole genomic DNA sequencing and comparative genomic analysis of Arthrospira platensis: high genome plasticity and genetic diversity". DNA Research. 23 (4): 325–38. doi:10.1093/dnares/dsw023. PMC 4991836. PMID 27330141.
  4. ^ Kebede E, Ahlgren G (October 1996). "Optimum growth conditions and light utilization efficiency of Spirulina platensis (= Arthrospira fusiformis) (Cyanophyta) from Lake Chitu, Ethiopia". Hydrobiologia. 332 (2): 99–109. doi:10.1007/bf00016689. S2CID 32546529.
  5. ^ Capelli, Bob; Cysewski, Gerald R. (April 2010). "Potential health benefits of spirulina microalgae*: A review of the existing literature". Nutrafoods. 9 (2): 19–26. doi:10.1007/BF03223332. S2CID 40624847.
  6. ^ Small, Ernest (December 2011). "37. Spirulina – food for the universe". Biodiversity. 12 (4): 255–265. doi:10.1080/14888386.2011.642735. S2CID 120504029.
  7. ^ Grossmann, Lutz; Hinrichs, Jörg; Weiss, Jochen (24 September 2020). "Cultivation and downstream processing of microalgae and cyanobacteria to generate protein-based technofunctional food ingredients". Critical Reviews in Food Science and Nutrition. 60 (17): 2961–2989. doi:10.1080/10408398.2019.1672137. PMID 31595777. S2CID 203985553.
  8. ^ Böcker, Lukas; Bertsch, Pascal; Wenner, David; Teixeira, Stephanie; Bergfreund, Jotam; Eder, Severin; Fischer, Peter; Mathys, Alexander (February 2021). "Effect of Arthrospira platensis microalgae protein purification on emulsification mechanism and efficiency". Journal of Colloid and Interface Science. 584: 344–353. Bibcode:2021JCIS..584..344B. doi:10.1016/j.jcis.2020.09.067. hdl:20.500.11850/442458. PMID 33070074. S2CID 224782082.
  9. ^ Buchmann, Leandro; Bertsch, Pascal; Böcker, Lukas; Krähenmann, Ursina; Fischer, Peter; Mathys, Alexander (December 2019). "Adsorption kinetics and foaming properties of soluble microalgae fractions at the air/water interface". Food Hydrocolloids. 97: 105182. doi:10.1016/j.foodhyd.2019.105182. hdl:20.500.11850/349196. S2CID 197138756.
  10. ^ Bertsch, Pascal; Böcker, Lukas; Palm, Ann-Sophie; Bergfreund, Jotam; Fischer, Peter; Mathys, Alexander (March 2023). "Arthrospira platensis protein isolate for stabilization of fluid interfaces: Effect of physicochemical conditions and comparison to animal-based proteins". Food Hydrocolloids. 136: 108290. doi:10.1016/j.foodhyd.2022.108290. hdl:20.500.11850/579831.
  11. ^ Martelli, Giulia; Folli, Claudia; Visai, Livia; Daglia, Maria; Ferrari, Davide (January 2014). "Thermal stability improvement of blue colorant C-Phycocyanin from Spirulina platensis for food industry applications". Process Biochemistry. 49 (1): 154–159. doi:10.1016/j.procbio.2013.10.008.
  12. ^ Dutta, Debajyoti; De, Debojyoti; Chaudhuri, Surabhi; Bhattacharya, Sanjoy K (December 2005). "Hydrogen production by Cyanobacteria". Microbial Cell Factories. 4 (1): 36. doi:10.1186/1475-2859-4-36. PMC 1343573. PMID 16371161.