The Marsh Barbel is native to the Indian subcontinent, including Nepal and Sri Lanka, the Andaman Islands and the Nicobar Islands, as well as to Malaysia, South East Asia and parts of Africa, including South Africa, Senegal, Sudan, Cameroon, Guinea-Bissau, Nigeria and Mali. It has a few synonyms including Hygrophilia schulli and Asteracantha longiflolia and is known in English by many other names including the Temple Plant. It is a member of the Acanthaceae family and as the name suggests, likes to live in wet places. It can grow to 2 metres high or more, and has blue-purple flowers, with upper and lower “lips”. These flowers look a little like violas, or wild pansies.
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It contains vitamin C and flavonoids, phenolic compounds, saponins, steroid, terpenoids and cardiac glycosides.
In Ayurvedic medicine the plant is used for rheumatism, inflammation, jaundice and other liver problems and as a pain-killer.
Few clinical trials have been carried out on this plant, but the few that have were concentrated on proving the traditional uses of the Marsh Barbel. One study that was reported in the Journal of Ethnopharmacology in April 2006, conducted by M. Vijayakumar et al., concluded that it has “significant anti-diabetic activity along with potent antioxidant potential in diabetic condition.” However, the study was performed on rats and an extract of the plant used.
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While there is no doubt that the plant has medicinal value, given its traditional use over centuries, no scientific studies have been conducted on people.