MARSH MALLOW

Althaea officinalis

Mallow Family [Malvaceae]

month8aug month8sep month8sept

status
statusZnative
flower
flower8white
flower
flower8lilac
inner
inner8mauve
morph
morph8actino
petals
petalsZ5
type
typeZspiked
stem
stem8round
rarity
rarityZscarce

4th Sept 2013, Rye Harbour nature reserve, East Sussex. Photo: © Dawn Nelson
A scarce plant growing to 1.5m in clumps on brackish substrates near the sea. Each stem is upright, rigid and with short white hairs.


4th Sept 2013, Rye Harbour nature reserve, East Sussex. Photo: © Dawn Nelson
The white flowers with five petals are in sparse spikes up the stalk, concentrated more nearer the top.


4th Sept 2013, Rye Harbour nature reserve, East Sussex. Photo: © Dawn Nelson
The flowers have a lilac tinge. Leaves to 8cm across, between 3 - 5 lobes with a short white felted hair covering.


4th Sept 2013, Rye Harbour nature reserve, East Sussex. Photo: © Dawn Nelson
The stamens are pink to mauve, initially bunched into a tube but spreading out near the end into an ovaloid 'brush' of purple anthers. The style in the centre is taller and white to lilac (seen in the uppermost flower)


4th Sept 2013, Rye Harbour nature reserve, East Sussex. Photo: © Dawn Nelson
Ripe fruits gathered together close to the single stem.


4th Sept 2013, Rye Harbour nature reserve, East Sussex. Photo: © Dawn Nelson
A ripening fruit looks like a thick button and is half-enclosed by the 5 triangular inner calyx 'sepal' teeth once surrounding the flower bud. They are commonly called 'cheeses' on Mallow species. Besides the inner ring of 5 triangular sepals, there are a further 6 to 10 narrow outer sepals or epicalyx (some visible at 1 O'clock on the fruit).


4th Sept 2013, Rye Harbour nature reserve, East Sussex. Photo: © Dawn Nelson
The fruit is in many fused segments and has much the same short white hairs as the rest of the plant (bar the flower).


4th Sept 2013, Rye Harbour nature reserve, East Sussex. Photo: © Dawn Nelson
Leaves have very short white hairs.


Easily mistaken for : Common Mallow (Malva sylvestris) but Marsh Mallow is hoary woolly on stems and leaves, has paler flowers slightly flushed with lilac, and the outer epicalyx (sepals) which are narrow and number between 6 to 10. Marsh Mallow, in the Althea genera, is also in a differing genera to that of most other Mallows (Malva).

Marsh Mallow grows on brackish soils such as dykes, banks, drier salt-marshes and grassland by the sea. It also grows inland where it is shorter and may be mistaken for Hollyhock (Alcea rosea).

Marsh Mallow gives its name to a sweet no longer made from the roots of Marsh Mallow when it was more abundant. It is scare now. The whole plant, but particularly the roots, contain a moist mucilageous substance, much more than does Common Mallow (Malva sylvestris) which is used to make the sweetmeal. The flowers and leaves are also edible and can be added to salads or boiled or fried.

The mucilageous substance was traditionally used to treat the mucous membranes of humans, for bronchitis, sore throats and gastric ulcers.

The plant contains a lactone, AltheaHexacosenyl Lactone (n-hexacos-2-enyl-1,5-olide) for which the Author cannot find the structural formula.

STEROIDS

Two steroidal compounds Lanosterol and β-Sitosterol are found in the plant. All plant steroids are said to be derived from the steroid Cycloartenol, whilst those steroids of fungi and animamls are all derived from Lanosterol, so the Author does not know why Lanosterol is found in this plant, but there you go; apparently it is - plants are not renown for keeping to the rules. Studies on some animals have found that it can prevent or even improve cataracts in the eye.

2β-HYDROXYCALAMENE

The sesquiterpenoid AltheaCalamene (2β-HydroxyCalamene) is a hydroxy Calamene found in Marsh Mallow. Calamene itself is a sesquiterpene found in Sweet Flag Acorus calamus, hence its name.

A FATTY ACID COUMARIN GLYCOSIDE


AltheaCoumarin Glucoside (5,6-dihydroxycoumarin-5-dodecanoate-6β-D-glucopyranoside) is a substituted dihydroxycoumarin. A glycosidic group replaces one of the H groups of the OH, whilst the other is replaced by a Lauric Acid moiety.


A FATTY ACID


This C12 saturated fatty acid Lauric Acid (aka n-Dodecanoic Acid) is also found which smells faintly of bay oil (which is not obtained from our Bay Tree but from West Indian Bay Tree (Pimenta racemosa).

It is non-toxic and used in the manufacture of soaps and cosmetics by reacting it with sodium hydroxide NaOH to produce the sodium salt Sodium Laurate.

As the third fatty acid component in Triglycerides it is found in Coconut Oil, Laurel Oil (hence the name) and very few other plants. It constitutes about 6% of human breast milk and about 3% of cow's or goat's milk. Because it has a propensity to increase high density lipoproteins (HDL - the so-called 'good' cholesterol) it can contribute to a lower risk of atherosclerosis.


  Althaea officinalis  ⇐ Global Aspect ⇒ Malvaceae  

Distribution
 family8Mallow family8Malvaceae

 BSBI maps
genus8Althaea
Althaea
(Marsh-Mallow)

MARSH MALLOW

Althaea officinalis

Mallow Family [Malvaceae]