MACOI - Portuguese Seaweeds Website

Class:

Bangiophyceae

Genus:

Porphyra C. Agardh

Species:

Porphyra umbilicalis

Authority:

(Linnaeus) Kützing

Description:

A red alga (up to 40 cm across) with a circular (P. umbilicalis) or irregularly shaped (P. leucosticta), broad frond that is membranous but tough. The plant attaches to rock via a minute discoid hold-fast, is greenish when young becoming purplish-red and has a polythene-like texture. Another species is the P. linearis, with narrow stem that attaches the base and appears mainly in winter (Pereira, 2010).

Link for Algae Handbook (Pereira, 2010).

Original publication: Kützing, F.T. (1843). Phycologia generalis oder Anatomie, Physiologie und Systemkunde der Tange... Mit 80 farbig gedruckten Tafeln, gezeichnet und gravirt vom Verfasser. pp. [part 1]: [i]-xxxii, [1]-142 , [part 2:] 143-458, 1, err.], pls 1-80. Leipzig: F.A. Brockhaus.

Download PDF from Algaebase

Porphyra umbilicalis is a relative of the Japanese sushi nori, Pyropia yezeonensis. It is a relatively small seaweed; individuals are usually 5 to 10 centimeters tall, and up to 20 centimeters across. Porphyra umbilicalis has an irregularly shaped, broad frond that is membranous but tough. A common form is where the blade expands around the holdfast and appears pleated or resembles a rosette or a little cabbage. The plants are just one cell layer thick and translucent, but show extreme resilience in the surf, holding itself in place with a tiny disk-like holdfast. Porphyra umbilicalis exhibits a variety of colors and hues. The blades are greenish when young, then become purplish-red and light to dark reddish-brown. At low tide, the plants lie plastered on the rock ledges in pink, purple, and black hues. They dry in the sun to a lustrous black, and can also turn green in summer because of low nutrients and exposure to temperatures above its tolerance level at low tide.

Porphyra umbilicalis has a short lifespan, but because is reproduces quickly it can be found almost throughout the year, growing on wave beaten rocks on exposed beaches, although it can prefer shaded areas. It is found on a wide range of hard surfaces, including bedrock, boulders, concrete, wood and on the shells of sea creatures such as limpets, mussels and barnacles. It can also be epiphytic, attached to other seaweeds. Porphyra umbilicalis occurs singly or in dense colonies throughout the mid-intertidal but most frequently in the upper part of the shore where it sometimes forms a colony and distinct zone. It is highly adaptable to conditions on different parts of the rocky shore and able to withstand drying during prolonged periods of exposure to the air during low tide, as well as tolerating a greater degree of wave action than most other red algae. Porphyra umbilicalis also contains natural ultraviolet (UV) sunscreens.

Link for Seaweed Industry Association

Name History

Nomenclatural notes: Brodie et al. (2008: 1328) present convincing evidence that Kützing's (1843: 383) binomial should not be considered a "presumed new combination" for Ulva umbilicalis Linnaeus under Art. 33.3 of the ICBN, and should be regarded as a separate nomenclatural act. J. Agardh's (1883) combination of Ulva umbilicalis into Porphyra is also a separate nomenclatural act, and represents a later and thus illegimate homonym. Brodie et al. (2008: 1328) also designate a neotype from Scotland for Porphyra umbilicalis Kützing and at the same time designate this specimens as the epitype of Ulva umbilicalis Linnaeus (1753), thus consolidating the taxonomic integrity of all three names. - (10 Dec 2008) - Wendy Guiry

Biogeography

Porphyra umbilicalis occurs in the North Atlantic. In the east, it is found in Iceland and has been recorded from Norway to Portugal and in the Western Mediterranean. In the west, Porphyra umbilicalis is found from Labrador in Canada to the mid-Atlantic coast of the United States.

Life Cycle

Gametophyte thallus reddish brown, brownish, grey brown or olive green in the field, drying to brownish purple, attached by a minute but stout holdfast; stipe indistinct; blade orbiculate to elongate, auriculate and/or cucullate; base slightly to extremely cordate, overlapping to appear umbilicate; margins sometimes much pleated; blades single or multiple, sometimes forming a rosette. Thallus monostromatic, 58–70 µm thick with cells in surface view 8–16 × 6–8 µm and in transverse section 30–34 × 9–10 µm. Usually dioecious; sori marginal; male gametangia in packets of 4 × 4 in surface view and ×8 in transverse section ( = 128 gametes); zygotosporangia in packets of 2 × 4 in surface view and ×2 in transverse section ( = 16 zygotospores). Neutral sporangia are sometimes present.

Uses and compounds

High antioxidant activity Zubia et al. 2009).

Direct use as food - food, consumed whole

Health - mineral supplement; Contains: ascorbic acid (vitamin C).

Source of organic chemicals - source of polyols; Contains: mannitol.

Other uses: Porphyra umbilicalis is rich in protein, vitamins A, C, E, and B, and trace minerals, and also rich in omega-3 polyunsaturated fatty acids (EPA and DHA). It contains special compounds named "mycosporine-like amino acids" (MAAs) which are valuable in certain types of personal care products. Some of the favorable properties associated with compounds from Porphyra umbilicalis are that it:

acts as a natural bio-protector against UVA induced damage
prevents the formation of "sun burn cells" and premature photo-aging
protects cell structures, especially membrane lipids and DNA from damage by UV-induced radicals
helps in the re-equalization of lipid deficient skins
increases epidermal hydration
protects against Trans Epidermal Water Loss
improves intercellular cohesion
reinforces the skin barrier function
restores cell membrane structure after irritant damage
has oxygenating properties that helps revitalize stressed and fatigued skin
able to diminish the appearance of fine lines and wrinkles

As a result, it is used in many different product application, such as:

daily UV protective skin care, sun care,
anti-photo-aging care
cares for dry, reactive and sensitive skins
lip care
after sun care

Specific products identified so far from France, Ireland, Italy, Spain, United States utilizing Porphyra umbilicalis include regenerating face creams and anti-aging facial creams, facial masks, and aftershave balm. For food, it is sold in flaked and whole leaf form, as a nori substitute, as laver, and is used as an ingredient in several snack mixes and condiments. It is also used as a pet nutrition supplement.

Harvesting: Harvesting of Porphyra umbilicalis is known to occur in France, UK, Ireland, Canada, and the northeastern United States.

Harvesting Techniques: For Porphyra umbilicalis, scissors or a small knife can be used to carefully cut the blade from the holdfast. If the holdfast is accidentally pulled off from the substrate, the holdfast can be cut from the frond before processing. It should be quickly rinsed in seawater to remove any small animals.

References

Kützing, F.T. (1843). Phycologia generalis oder Anatomie, Physiologie und Systemkunde der Tange... Mit 80 farbig gedruckten Tafeln, gezeichnet und gravirt vom Verfasser. pp. [part 1]: [i]-xxxii, [1]-142 , [part 2:] 143-458, 1, err.], pls 1-80. Leipzig: F.A. Brockhaus.
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Bates, C.R., Saunders, G.W. & Chopin, T. (2005). An assessment of two taxonomic distinctness indices for detecting seaweed assemblage responses to environmental stress. Botanica Marina 48: 231-243.

Braune, W. (2008). Meeresalgen. Ein Farbbildführer zu den verbreiteten benthischen Grün- Braun- und Rotalgen der Weltmeere. pp. [1]-596, 266 pls. Ruggell: A.R.G. Gantner Verlag.

Brodie, J. & Irvine, L.M. (2003). Seaweeds of the British Isles. Volume 1. Rhodophyta. Part 3B. Bangiophycidae. pp. xiii + 167 + map. Andover: Intercept.

Brodie, J. Irvine, L., Neefus, C.D. & Russell, S. (2008). Ulva umbilicalis Linnaeus and Kützing (Rhodophyta, Bangiaceae): a molecular and morphological redescription of the species, with a typification update. Taxon 57: 1328-1331, 1 fig.

Klein, A.S, Mathieson, A.C., Neefus, C.D., Cain, D.C., Taylor, H.A., Teasdale, B.W., West, A.L., Hehre, E.J., Brodie, J., Yarish, C. & Wallace, A.L. (2003). Identification of north-western Atlantic Porphyra (Bangiaceae, Bangiales) based on sequence variation in nuclear SSU and plastid rbcL genes. Phycologia 42: 109-122, 3 figs, 5 tables.

Lindstrom, S.C. & Fredericq, S. (2003). rbcL gene sequences reveal relationships among north-east Pacific species of Porphyra (Bangiales, Rhodophyta) and a new species, P. aestivalis. Phycological Research 51(3): 211-224.

Loiseaux-de Goër, S. & Noailles, M.-C. (2008). Algues de Roscoff. pp. [1]-215, col. figs. Roscoff: Editions de la Station Biologique de Roscoff.

Habitat:

Marine species, on rocks, mussels, etc., midtidal to splash zone, generally distributed, abundant, especially on exposed coasts.

Common names:

In English: Purple Laver; Pink Laver; Laver

In Portuguese: Erva patinha; Folhuda;

In Trade Worldwide: Nori;

In German: Porphyrtang;

In Japanese: Chishima-kuro-nori

Other names: an sleabhac, chishima-kuro-nori, kim, laver, laver seaweed, Nabel-Hauttang, navelwier, navle-purpurhinde, porphyre, Porphyrtang, puperwier, purperwier, purple laver, sloke, vanleg fjørehinne, vanlig fjærehinne, veckad purpurtång, wild Atlantic nori.

Type information:

Type locality: Scotland: Easdale, Argyll (Brodie et al. 2008: 1330). Neotype: J. Brodie & P.K. Hayes; 23 July 1998; From the back of a limpet. BM 000769632 (Brodie et al. 2008: 1330). Notes: Illustrated in Brodie et al. (2008: fig. 1 B).