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porphyra

{{Short description|Genus of seaweed}}

{{About||the color known in Greek as porphyra|Tyrian purple|species previously in this genus that have been reclassified as pyropia|Pyropia}}

{{Distinguish|Porphyria}}

{{Automatic taxobox

| image = Porphyra umbilicalis, Porphyra purpurea Helgoland.JPG

| image_caption = Porphyra umbilicalis (right) and Porphyra purpurea (front), in Heligoland

| image_alt = Porphyra umbilicalis (right) and Porphyra purpurea (front), in Heligoland

| taxon = Porphyra

| authority = C.Agardh 1824

| subdivision_ranks = Species

| subdivision_ref = Guiry, Michael D. (2012). Porphyra. In: Guiry, M.D. & Guiry, G.M. (2017). AlgaeBase. World-wide electronic publication, National University of Ireland, Galway (taxonomic information republished from AlgaeBase with permission of M.D. Guiry). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=143808 on 2017-09-06

| subdivision = see text

| synonyms = Conchocelis Batters 1892

Phyllona J.Hill 1773

| synonyms_ref =

}}

Porphyra is a genus of coldwater seaweeds that grow in cold, shallow seawater. More specifically, it belongs to red algae phylum of laver species (from which comes laverbread), comprising approximately 70 species.Brodie, J.A. and Irvine, L.M. 2003. Seaweeds of the British Isles. Volume 1 Part 3b. The Natural History Museum, London.{{ISBN|1 898298 87 4}} It grows in the intertidal zone, typically between the upper intertidal zone and the splash zone in cold waters of temperate oceans. In East Asia, it is used to produce the sea vegetable products nori (in Japan) and gim (in Korea). There are considered to be 60–70 species of Porphyra worldwideKain, J.M. 1991. Cultivation of attached seaweeds. in Guiry, M.D. and Blunden, G. 1992. Seaweed Resources in Europe: Uses and Potential. John Wiley and Sons, Chichester {{ISBN|0-471-92947-6}} and seven around Britain and Ireland, where it has been traditionally used to produce edible sea vegetables on the Irish Sea coast.Hardy, F.G. and Guiry, M.D. 2006. A Check-list and Atlas of the Seaweeds of Britain and Ireland. British Phycological Society, London. {{ISBN|3-906166-35-X}} The species Porphyra purpurea has one of the largest plastid genomes known, with 251 genes.[https://books.google.com/books?id=E-MXsGnAVAQC&dq=%22red+alga+Porphyra+purpurea+%28251+genes%29%22&pg=PA878 The Chlamydomonas Sourcebook: Organellar and Metabolic Processes Volum 2]

Life cycle

Porphyra displays a heteromorphic alternation of generations.[http://www.mbari.org/staff/conn/botany/reds/lisa/lhist.htm Porphyra life cycle] {{webarchive|url=https://web.archive.org/web/20070411151035/http://www.mbari.org/staff/conn/botany/reds/lisa/lhist.htm |date=2007-04-11 }} The thallus we see is the haploid generation; it can reproduce asexually by forming spores which grow to replicate the original thallus. It can also reproduce sexually. Both male and female gametes are formed on the one thallus. The female gametes while still on the thallus are fertilized by the released male gametes, which are non-motile. The fertilized, now diploid, carposporangia after mitosis produce spores (carpospores) which settle, then bore into shells, germinate and form a filamentous stage. This stage was originally thought to be a different species of alga, and was referred to as Conchocelis rosea. That Conchocelis was the diploid stage of Porphyra was discovered in 1949 by the British phycologist Kathleen Mary Drew-Baker for the European species Porphyra umbilicalis.{{cite journal |last1= Drew |first1= Kathleen M. |year=1949 |title= Conchocelis-phase in the life-history of Porphyra umbilicalis (L.) Kütz|journal=Nature |volume= 164|issue= 4174|pages= 748–749|doi= 10.1038/164748a0|bibcode= 1949Natur.164..748D |s2cid= 4134419 }} It was later shown for species from other regions as well.Thomas, D. 2002. Seaweeds. The Natural History Museum, London. {{ISBN|0-565-09175-1}}

Food

Most human cultures with access to {{lang|la|Porphyra}} use it as a food or somehow in the diet, making it perhaps the most domesticated of the marine algae,Mumford, T.F. and Miura, A. 4.Porphyra as food: cultivation and economics. in Lembi, C.A. and Waaland, J.R. 1988. Algae and Human Affairs. Cambridge University Press, Cambridge. {{ISBN|0-521-32115-8}} known as laver, {{lang|vi|rong biển}} (Vietnamese), nori (Japanese:{{lang|ja|海苔}}), amanori (Japanese),{{cite book|last=Abbott|first=Isabella A|author-link=Isabella Abbott|type=Food and food products from seaweeds|editor1-last=Lembi|editor1-first=Carole A.|editor2-last=Waaland|editor2-first=J. Robert|title=Algae and human affairs|year=1989|pages=141|publisher=Cambridge University Press, Phycological Society of America|isbn= 978-0-521-32115-0}} zakai, gim (Korean:{{lang|ko|김}}), zǐcài (Chinese:{{Lang|zh|紫菜}}), karengo, sloke or slukos. The marine red alga Porphyra has been cultivated extensively in many Asian countries as an edible seaweed used to wrap the rice and fish that compose the Japanese food sushi and the Korean food gimbap. In Japan, the annual production of Porphyra species is valued at 100 billion yen (US$1 billion).Aoki, Y. and Kamei, Y. 2006 Preparation of recombinant polysaccharide-degrading enzymes from the marine bacterium, Pseudomonas sp. ND137 for the production of protoplasts of Porphyra yezoensis Eur. J. Phycol. 41: 321-328.

{{lang|la|P.{{nbsp}}umbilicalis}} is harvested from the coasts of Great Britain and Ireland, where it has a variety of culinary uses, including laverbread.{{cite web |title= Laver Seaweed – A Foraging Guide to Its Food, Medicine and Other Uses |url=https://www.eatweeds.co.uk/laver-porphyra |website=eatweeds.co.uk |date=30 August 2018 |access-date=22 March 2021}} In Hawaii, "the species {{lang|la|P.{{nbsp}}atropurpurea}} is considered a delicacy, called {{lang|haw|Limu luau}}". Porphyra was also harvested by the Southern Kwakiutl, Haida, Seechelt, Squawmish, Nuu-chah-nulth, Nuxalk, Tsimshian, and Tlingit peoples of the North American Pacific coast.

Vitamin B12

Porphyra contains vitamin B12 and one study suggests that it is the most suitable non-meat source of this essential vitamin.{{cite journal |vauthors=Watanabe F, Yabuta Y, Bito T, Teng F |title=Vitamin B₁₂-containing plant food sources for vegetarians |journal=Nutrients |volume=6 |issue=5 |pages=1861–73 |date=May 2014 |pmid=24803097 |pmc=4042564 |doi=10.3390/nu6051861 |quote="A nutritional analysis of six vegan children who had consumed vegan diets including brown rice and dried purple laver (nori) for 4–10 years suggested that the consumption of nori may prevent Vitamin B12 deficiency in vegans."|doi-access=free }} In the view of the Academy of Nutrition and Dietetics, however, it may not provide an adequate source of B12 for vegans.{{cite journal| vauthors=Melina V, Craig W, Levin S| title=Position of the Academy of Nutrition and Dietetics: Vegetarian Diets |journal=J Acad Nutr Diet|year= 2016|volume= 116|issue= 12|pages= 1970–1980|pmid=27886704|doi=10.1016/j.jand.2016.09.025| s2cid=4984228 |quote=Fermented foods (such as tempeh), nori, spirulina, chlorella algae, and unfortified nutritional yeast cannot be relied upon as adequate or practical sources of B-12.39,40 Vegans must regularly consume reliable sources— meaning B-12 fortified foods or B-12 containing supplements—or they could become deficient, as shown in case studies of vegan infants, children, and adults.|url=https://pubmed.ncbi.nlm.nih.gov/27886704/}}

Species

Porphyra currently contains 57 confirmed species and 14 unconfirmed species.{{cite WoRMS |author=Michael D. Guiry |year= 2024|title= Porphyra C.Agardh, 1824|id= 143808|accessdate=17 April 2024}}

=Confirmed=

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=Unconfirmed=

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Following a major reassessment of the genus in 2011, many species previously included in Porphyra have been transferred to Pyropia: for example Pyropia tenera, Pyropia yezoensis, and the species from New Zealand Pyropia rakiura and Pyropia virididentata, leaving only five species out of seventy still within Porphyra itself.{{cite journal|author=Sutherland|title=A New Look at an Ancient Order: Generic Revision of the Bangiales (Rhodophyta)|journal=J. Phycol.|date=October 2011|volume=47|issue=5|pages=1131–1151|doi=10.1111/j.1529-8817.2011.01052.x|pmid=27020195|s2cid=2779596|display-authors=etal}}

See also

References

{{Reflist|2}}

External links

  • {{Commons category-inline|Porphyra|Porphyra}}
  • {{Wikispecies-inline|Porphyra|Porphyra}}
  • [https://www.youtube.com/watch?v=4DxnL1DwA6w Video footage of Laverbread or Bara Lawr]

{{Taxonbar|from=Q2104475}}

{{Authority control}}

Category:Red algae genera

Category:Bangiophyceae

Category:Edible seaweeds

Category:Seaweeds

Category:Edible algae

Category:Taxa named by Carl Adolph Agardh