Menyanthes trifoliata L. - Menyanthaceae - marsh trefoil, buckbean, bogbean, Dreiblättriger Fieberklee, Bitterklee, Wasserdreiblatt
Perennial herb, up to 30cm tall, native to fens and bogs of the northern hemisphere; rhizomes usually in mud but sometimes floating; leaves alternate, trifoliate, leaflets elliptic, entire or crenulate, apex obtuse, midvein distinct, 2.5-4cm; inflorescences many flowered, racemes including scape 30-35cm; flower calyx 4-5mm, corolla white, tubular, 1.4-1.7cm, outside glabrous, inside long fimbriate pilose, lobes elliptic-lanceolate, 7.5-10mm, apex obtuse; seeds orbicular, 2-2.5mm in diam. http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200018194
The dried leaves (Menyanthidis folium, Trifolii fibrini folium, bogbean leaf, Fieberkleeblätter, Bitterkleeblätter) have been used traditionally to treat cold, fever and skin disorders, loss of appetite, dyspeptic complaints, as cholagogue, in geriatric medicines and also in anti-inflammatory and antirheumatic formulations. „The leaves contain bitter-tasting secoiridoid glycosides, including dehydromenthiafolin (main component), menthiafolin and loganin, as well as coumarins (scopoletin, scoparone, braylin)… Scopoletin and scoparone are known to act as cholagogues and choleretics and have antihepatotoxic activity. Scopoletin is stated to have a spasmolytic effect.“
Very large doses of the leaves may cause diarrhoea, nausea and vomiting.
[Medicinal Plants of the World. Ben-Erik Van Wyk and Michael Wink, Pretoria 2004, 208]
„The characteristic bitter principle (Ph.Eur. min. bitterness value 3000) are dimeric secoiridoid glucosides. A monoterpene acid derived from nerol is linked to the secoiridoid skeleton like in dihydrofoliamenthin, the main component of the leaves.“ In menthiafolin, a monoterpene acid derived from linalool is linked to the sweroside part.
[Wolfgang Blaschek ed., Wichtl - Teedrogen und Phytopharmaka: Ein Handbuch für die Praxis, 2015, 229-231]
[Further investigations regarding distribution and structure of the bitter principles from Menyanthes trifoliata., Junior, P., Planta medica, 55(1), 1989, 83-87]
Kohl,F.G., Die officinellen Pflanzen der Pharmacopoea Germanica, t.123 (1891-1895)
Menyanthes trifoliata © Rolf Marschner (2010)