Clearing Nut

Strychnos potatorum

Physical Characteristics

Strychnos potatorum is a deciduous Tree growing to 12 m (39ft) by 12 m (39ft) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 10. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in full shade (deep woodland) or semi-shade (light woodland). It prefers dry or moist soil and can tolerate drought.

Distribution

E. Asia - India, Myanmar. Tropical Africa - DR Congo to Tanzania, south to northern S. Africa.

Habitats

Edible Uses

Edible Parts: Fruit Edible Uses: Coffee Young fruits - occasionally eaten or made into preserves[2 , 146 , 301 ]. The pulp is eaten[652 ]. They are an ingredient of 'Raja's Cup', an Ayurvedic coffee substitute[301 ]. The fruit is a sub-globose berry 12 - 18mm in diameter with a firm pericarp, black when ripe, containing 1 - 2 seeds in a whitish pulp[652 ].

Medicinal Uses

Antiasthmatic Antidiarrhoeal Antitussive Aphrodisiac Cardiac Diuretic Epilepsy Hypotensive Kidney Ophthalmic The pounded leaves are used to treat watering and aching eyes[299 ]. A decoction is taken to treat epilepsy[299 ] The roots are aphrodisiac[299 ]. The vapour of a root decoction is inhaled to treat colds and venereal diseases[299 ]. A decoction of the roots and leaves is taken to treat cough[299 ]. The seeds are used for the treatment of a range of complaints including those affecting the liver, kidneys and stomach; gonorrhoea, leucorrhoea, bronchitis, chronic diarrhoea, strangury, kidney and bladder stones, diabetes and eye diseases[299 ]. The plant contains many monomeric and dimeric indole alkaloids, the root bark being especially rich. The monoterpene alkaloid cantleyine, isolated from the root bark, has shown a relaxing effect on isolated tracheal smooth muscles and may be the active ingredient responsible for the anti-cough and anti-asthmatic activity[299 ]. Normacusine B, a monomeric alkaloid of the corynanthe class, also found in Rauvolfia, Tabernaemontana and Vinca spp., is sympatholytic and its hypotensive activity is stronger than that of reserpine, which is commonly used against high blood pressure[299 ]. The total alkaloid extracts of the seeds, bark and leaves showed strychnine-like activity in vivo, had marked hypotensive effect and exhibited a depressant action on isolated heart muscle[299 ]. In-vivo tests using the seed powder and an aqueous extract of the seeds prevented ulcer formation by decreasing acid secretory activity and increasing the mucin activity[299 ]. An aqueous extract of the seeds has shown significant hepatoprotective activity[299 ]. A methanol extract of the seeds had a diuretic effect and an antidiarrhoeal activity on castor oil-induced diarrhoea[299 ].

Known Hazards

The pounded fruits are used as fish poison[299 ]. The crushed bark is used as a fish poison[299 ].