(Mimosa pudica)

Mimosa flower

Mimosa_pudica picture

Leaves closed

Kingdom: Plantae
Family: Fabaceae
Genus: Mimosa
Species: pudica
Common names: sensitive plant, sleepy plant, humble plant, shameful plant, slrrping grass, ant-plant and the touch-me-not. Condiamor
Part Used: Leaf, Seed, Root

Documented Properties
& Actions:
Antibiotic, antimicrobial, anti-neurasthenic, antispasmodic, diuretic, nervine, poison, sedative Its extract immobilizes the filariform larvae of Roundworm (Strongyloides stercoralis) in less than one hour. In contemporary medicine, Mimosa pudica is being investigated for its potential to yield novel chemotherapeutic compounds. It contains an alkaloid called mimosine, which has been found to have potent antiproliferative and apoptotic effects. Aqueous extracts of the roots of the plant have shown significant neutralizing effects on the lethality of the venom of the coral snake and the monocled cobra (Naja Kaouthia). It appears to inhibit the myotoxicity and enzyme activity of cobra venom. Antibiotic, antimicrobial, anti-neurasthenic, antispasmodic, diuretic, nervine, poison, sedative
Ascorbic-acid, crocetin, crocetin-dimethyl-ether, D-glucuronic-acid, D-xylose, linoleic-acid, linolenic-acid, mimosine, mucilage, norepinephrine, oleic-acid, palmitic-acid, sitosterol, stearic-acid

Ethnobotanical Uses

With a name that literally means "shy," the Mimosa pundica is a particularly unique piece of flora, as it responds to touch by folding inward to protect itself from predators. Wondering if this was just a straightforward reflex, the Australian researchers rigged up an apparatus that would drop water on the plant in both high- and low-light environments. Much to their surprise, they found that the plant stopped opening and closing once it learned that the drops weren't harmful. More impressively, the plants remembered that lesson several weeks after the initial training.

Also called sensitive plant, sleepy plant and the touch-me-not), is a creeping annual or perennial herb often grown for its curiosity value: the compound leaves fold inward and droop when touched or shaken, to protect them from predators, re-opening minutes later. The species is native to South America and Central America, but is now a pantropical weed.

East Indians of Belize relish ripe soroso fruits in curry dishes. A related cultivar of this plant is the well known "bitter melon" used in Oriental cuisine. Research Results

There has been a great deal of pharmacological research on this plant and the resulting literature is quite complex and sometimes contradictory. Caution is advised when ingesting this plant, as more than one source points to its toxicity when taken orally, and pregnant women should avoit it completely. Jelliffe et al. (1954) suggested that the use of this plant may be associated with the development of acute veno-occlusive disease of the liver in Jamaican children. The TRAMIL 4 workshop classified the internal use of the fruit as toxic, but suggested that external use of the leaves and stems was wrothy of further investigation.

Habitat; Mimosa pudica is native to South America and Central America. It has been introduced to many other regions and is regarded as an invasive species in Tanzania, South Asia and South East Asia and many Pacific Islands. It is regarded as invasive in parts of Australia and is a declared weed in the Northern Territory, and Western Australia although not naturalized there. Control is recommended in Queensland. It has also been introduced to Nigeri In the United States of America, it grows in Florida, Hawaii, Virginia, Maryland, Puerto Rico, Texas, and the Virgin Islands.


Mimosa pudica in Goa, India.The stem is erect in young plants, but becomes creeping or trailing with age. The stem is slender, branching, and sparsely to densely prickly, growing to a length of 1.5 m (5 ft). The leaves of the mimosa pudica are compound leaves.

The leaves are bipinnately compound, with one or two pinnae pairs, and 10-26 leaflets per pinna. The petioles are also prickly. Pedunculate (stalked) pale pink or purple flower heads arise from the leaf axils. The globose to ovoid heads are 810 mm in diameter (excluding the stamens). On close examination, it is seen that the floret petals are red in their upper part and the filaments are pink to lavender. The fruit consists of clusters of 2-8 pods from 12 cm long each, these prickly on the margins. The pods break into 2-5 segments and contain pale brown seeds some 2.5 mm long. The flowers are pollinated by the wind and insects. The seeds have hard seed coats which restricts germination.

Plant movement;
Mimosa pudica is well known for its rapid plant movement.

Mimosa pudica with leaves closedLike a number of other plant species, it undergoes changes in leaf orientation termed "sleep" or nyctinastic movement. The foliage closes during darkness and reopens in light.

The leaves also close under various other stimuli, such as touching, warming, blowing, or shaking. These types of movements have been termed seismonastic movements. The movement occurs when specific regions of cells lose turgor pressure, which is the force that is applied onto the cell wall by water within the cell vacuoles and other cell contents. When the plant is disturbed, specific regions on the stems are stimulated to release chemicals which force water out of the cell vacuoles and the water diffuses out of the cells, producing a loss of cell pressure and cell collapse; this differential turgidity between different regions of cells results in the closing of the leaflets and the collapse of the leaf petiole. This characteristic is quite common within the Mimosoideae subfamily of the legume family, Fabaceae. The stimulus can also be transmitted to neighboring leaves. It is not known exactly why Mimosa pudica evolved this trait, but many scientists think that the plant uses its ability to shrink as a defense from predators. Animals may be afraid of a fast moving plant and would rather eat a less active one. Another possible explanation is that the sudden movement dislodges harmful insects.