Ingeniero

Undaria Pinnatifida – a brown Macro-Alga from Asia
Related ingredient: MATRIGENICS. 14 G

Undaria Pinnatifida is a brown macro-alga from Japan, China and Korea where it is grown on ropes,
harvested and eaten for food. Its botanical name comes from the Latin unda meaning “wave” and pinnatifida,
which means “in the shape of a feather”.
Synonyms: W akame, Alaria pinnatifida, Alariaamplexicaulis, Ulopteryx pinnatifida

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BOTANICAL
Botanical family: Brown alga of the Alariaceae family
Undaria pinnatifida is a large brown alga which can grow up to 2 to 3 m long. Its average length in the
Mediterranean is between 0.5 and 1.2 m.
Its thallus (which is the vegetative tissue of lower plants that do not have leaves, roots and a stem) is made
of three parts: the fronds, the stipe andthe tendrils or haptera which the alga uses to fix itself to a substrate.
The frond is a foliated blade, straighter towards its tip, with a clearly defined, brown-green translucent medial
nerve. The edges are strongly denticulated and lobed, particularly towards the base. In the juvenile phase
the frond is completely straight with no denticulation. At maturity it becomes triangular withtransverse lobes.
The stipe is 10 to 20 cm long, 0.5 to 1 cm wide, thick and flat with denticulated edges. At maturity wavy
folded projections form towards the base called sporophylls. These contain the fertile structures.
The shape of the alga changes over time. The young thallus is elongated and ribbon like. On approaching
maturity it becomes wider and lobed. At the end of the cycle thesporophylls develop and the upper part of
the frond dies off. The shape in the adult state can vary with the frond denticulated to a greater or lesser
degree, a long or stubby stipe and wide or narrow sporophylls.
Reproduction: spores are produced by the stipe. These new tissues called fertile bases or Mekabu contain
the reproductive cells by which the species reproduces. When released into the sea, thereproductive cells
swim to a rocky substrate where they attach themselves and germinate to create a new alga. The fertile
bases alone represent a concentration of life that ensures the alga will continue to reproduce across the
centuries.

Blade = frond

Thallus

Fertile bases

Haptera

Fertile Bases = sporophylls

BIOTOPE
Undaria pinnatifida is cold temperate water alga whichcolonises the upper reaches of the shore, most
frequently in sites with strong currents but which are not subject to buffeting, i.e. in areas where waves do
not crash onto the shore. It cannot withstand being out of the water for long periods of time. Wakame
attaches itself to all sorts of solid substrates. These can be natural such as rocks, abalone shells and so on
or artificial such as portconstructions, hulls of ships, posts, anchor chains, ropes, shellfish tables, channels
etc.
It can form dense forests which compete with native species for space and light, often dominating them,
especially where there are no large indigenous algae.

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This ease with which it colonises various habitats is one of the reasons for the success in introducing it. In its
native habitat and whereit is introduced, wakame is highly tolerant to a wide variety of environmental
conditions in terms of temperature and salinity.
This would partly explain its wide geographic distribution in Europe from the Mediterranean to the North Sea.
Its distribution can range from the bottom of the foreshore (the part of the shore between the highest and
lowest known waterlines) down to a maximum depthof less than 18 m depending on the turbidity of the
water, i.e. its ability to diffuse or absorb ambient light. For instance, in the clear waters of Ouessant, an
island situated off the coast of Brittany in France, it can be found down to 18 m while in the turbid waters off
St Malo, it does not go below a depth of 13 m. In the Mediterranean it generally grows at less than 1.5 m
depth from...