Nostoc

Nostoc
Nostoc
Photo of N. azollae
Scientific classification
Kingdom: Bacteria
Phylum: Cyanobacteria
Class: see taxonomic note
Order: Nostocales
Family: Nostocaceae
Genus: Nostoc
Species

N. azollae
N. caeruleum
N. carneum
N. comminutum
N. commune
N. ellipsosporum
N. flagelliforme
N. linckia
N. longstaffi
N. microscopicum
N. muscorum
N. paludosum
N. pruniforme
N. punctiforme
N. sphaericum
N. sphaeroides
N. spongiaeforme
N. verrucosum

Nostoc is a genus of cyanobacteria found in a variety of environmental niches that forms colonies composed of filaments of moniliform cells in a gelatinous sheath.

The name "Nostoc" was invented by Paracelsus. [1] It derives from the ancient greek word "nόsos" (νόσος, "disease" or "sickness").

Nostoc can be found in soil, on moist rocks, at the bottom of lakes and springs (both fresh- and saltwater), and rarely in marine habitats. It may also grow symbiotically within the tissues of plants, such as the evolutionarily ancient (Gunnera) or hornworts, providing nitrogen to its host through the action of terminally differentiated cells known as heterocysts. These bacteria contain photosynthetic pigments in their cytoplasm to perform photosynthesis.

Contents

Species

Nostoc is a member of the family Nostocaceae of the order Hormogonales. Species include:

Non-scientific nomenclature

When on the ground, a Nostoc colony is ordinarily not seen; but after a rain it swells up into a conspicuous jellylike mass, which was once thought to have fallen from the sky, hence the popular names, fallen star, star jelly, Sternschnuppen (shooting stars), troll’s butter and witch’s jelly. It is also called witches' butter (not to be confused with the fungus Tremella mesenterica). Michael Quinion of the World Wide Words newsletter says that it is known in Welsh as pwdre sêr, or rot of the stars.[3]

Culinary use

Containing protein and vitamin C,[citation needed] Nostoc species are cultivated and consumed as a foodstuff, primarily in Asia. The N. flagelliforme and N. commune varieties are consumed in China, Japan and Java, N. commune is also consumed in the Andes. The preferred variety in Central Asia is N. ellipsosporum.

A research team from the biochemistry department of the Chinese University of Hong Kong said that international research has shown that fat choy (Nostoc flagelliforme), besides having no nutritional value, has also been found to contain Beta-methylamino L-alanine (BMAA), a toxic amino acid that could affect the normal functions of nerve cells. Professor Chan King-ming of the team told the media that eating fat choy could lead to degenerative diseases such as Alzheimer's, Parkinson's, and dementia.[4]

References

  1. ^ Potts M. (1997). "Etymology of the Genus Name Nostoc (Cyanobacteria)". International Journal of Systematic Bacteriology 47 (2): 484. http://ijs.sgmjournals.org/content/47/2/584.full.pdf. 
  2. ^ Abbott, Isabella A (1989). Lembi, Carole A.; Waaland, J. Robert. eds. Algae and human affairs. Cambridge University Press, Phycological Society of America. pp. 141. ISBN 9780521321150. 
  3. ^ Weird Words: Nostoc on World Wide Words
  4. ^ The standard.com.hk

External links

Guiry, M.D.; Guiry, G.M. (2008). "Nostoc". AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org/search/genus/detail/?genus_id=42976. 



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Look at other dictionaries:

  • Nostoc — commune Systematik Domäne: Bakterien (Bacteria) Abteilung: Cyanobakterien (Cyanobacter …   Deutsch Wikipedia

  • Nostoc — Crachat de lune …   Wikipédia en Français

  • nostoc — [ nɔstɔk ] n. m. • XVIIe nostoch; o. i., mot créé par Paracelse ♦ Bot. Algue bleue microscopique (cyanobactéries) qui forme des masses gélatineuses dans les sols humides. ● nostoc nom masculin Algue (cyanophycée) des sols humides et des eaux… …   Encyclopédie Universelle

  • Nostoc — Nos toc, prop. n. [F.] (Bot.) A genus of alg[ae]. The plants are composed of moniliform cells imbedded in a gelatinous substance. [1913 Webster] Note: {Nostoc commune} is found on the ground, and is ordinarily not seen; but after a rain it swells …   The Collaborative International Dictionary of English

  • nostoc — NOSTÓC s. m. algă albastră microscopică, din solurile umede. (< fr. nostoc) Trimis de raduborza, 15.09.2007. Sursa: MDN …   Dicționar Român

  • nostoc — [näs′täk΄] n. [ModL, coined by PARACELSUS Philippus Aureolus] any of a genus (Nostoc) of blue green algae, having twisted, coiled filaments embedded in a gelatinous material and forming spherical colonies …   English World dictionary

  • Nostoc — (N. Lyngb., Adans), Pflanzengattung aus der Familie der Nostochinae; am bekanntesten: N. commune (Tremella n. L.), zitternde Gallertalge, wellenförmig unförmlich gestaltete, braungrünliche, halbdurchsichtige, im Regen aufschwellende Substanz,… …   Pierer's Universal-Lexikon

  • Nostoc — Vauch. (Nostok, Schleimling, Zittertang, Zitteralge), Algengattung aus der Familie der Nostokazeen, blaugrüne Algen, deren kugelrunde Zellen in einer homogenen Schleimmasse rosenkranzartige Fäden bilden, in denen in bestimmten Abständen einzelne… …   Meyers Großes Konversations-Lexikon

  • Nostoc — Vauch., Zitteralge, Gallertalge, Algengattg. der Nostochazeen. N. commūne Vauch., perlschnurähnliche, von farblosen Grenzzellen unterbrochene Fäden [Abb. 1260] einzelliger, blaugrüner Algen, auf feuchtem Boden gallertige Lager bildend, die bei… …   Kleines Konversations-Lexikon

  • Nostoc — Crachat de lune Nostoc pr …   Wikipédia en Français

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