Agrostemma githago L. - syn.Githago segetum Link- Caryophyllaceae
corn cockle, cockle, corn-pink, Korn-Rade, Kornrade, Kornnelke
Annual herb, up to 1m high, nativer to Europe, naturalized in North America, South America, Australia; stem thinly hairy; leaves opposite, entire, linear or lanceolate; flowers purple, solitary at the end of the branches, petals pink, 2-3cm, oblanceolate, retuse; calyx tube 12-18mm, lobes 2-4cm, lanceolate-linear.
„Formerly a common weed of grain fields, Agrostemma githago is becoming increasingly scarce, both in North America and in its native environs in Europe. Mechanical screening of grain, which removes contaminants, and modern herbicides have more or less eliminated the plant from grain fields in the flora. The saponin-containing seeds, occurring as contaminants in grain, are poisonous to livestock, birds, and humans. This species is sometimes cultivated in flower gardens.“
The seeds were formerly used in folk medicine to treat skin impurities, gastritis, cough, worms and as diuretic. Efficiacy is not proven and the seeds are rather toxic. Ripe seeds contain triterpene glycosides, mainly githagosid, and minor saponins with quillaic acid as aglycone.
[Hagers Handbuch der Pharmazeutischen Praxis, Springer 2010]
[Über Triterpene, XXX. Über das Hauptsaponin der Kornrade (Agrostemma githago L.)., Tschesche, R., Schulze, H., Chemische Berichte, Vol.107(8), 1974, 2710-2719]
„… aqueous extracts of the seeds from Agrostemma githago L. proved to be remarkably more cytotoxic in comparison with isolated agrostemmasaponins in equal concentrations. A combination of agrostemmasaponin with a formyl function attached to triterpene position 4 together with agrostin, a ribosome-inactivating protein (RIP type 1; M ®: 27 kDa) which we isolated from the seed material, resulted in a markedly increased cytotoxicity… both compounds work as a functional unity showing a mechanism of 'cooperative toxicity'.“
[Cytotoxic activity of the seeds from Agrostemma githago var. githago., Hebestreit, P., Melzig, M.F., Planta medica, Vol.69(10), 2003, 921-925]
„Four saponins were isolated from Agrostemma githago L. Although three of these substances, Gypsophilasaponin 1-3, were already known from other species, they were described for this species for the first time. The structure of Agrostemmasaponin was elucidated as new substance and synergistically enhanced the cytotoxicity of RIP-I. A further amplification of the synergistic enhancement of the cytotoxicity of the RIP-I Agrostin that is also present in the species, compared to the synergistic enhancement of the cytotoxicity of the RIP-I
Saporin from Saponaria officinalis L. by the saponins isolated from Agrostemma githago L. was not detected.
A linear correlation between the membrane toxicity of saponins and their characteristic to lower the surface tension of aqueous solutions could be shown. A cell-based model using radiolabeled cholesterol was developed to analyze the influence of saponins on the cholesterol content of cell membranes. Results from the model showed, that membrane active saponins lowered the cholesterol content of cellmembranes. These saponins also hindered the uptake of free cholesterol into the cell membrane resulting in a decreased cholesterol content compared to a control. Saponins that are not membrane active did not influence the cholesterol content of cells in the same range of concentration.“
[Untersuchungen zur synergistischen Zytotoxizität zwischen Saponinen und Ribosomen inaktivierenden Proteinen Typ I, Böttger, S., (Doctoral dissertation, Freie Universität Berlin, Germany), 2013] http://www.diss.fu-berlin.de/diss/servlets/MCRFileNodeServlet/FUDISS_derivate_000000014542/eDissertation_StefanxBoettger.pdf
Köhler, F.E., Medizinal Pflanzen, vol.4 t.36 (1890)
Agrostemma githago flowers, CC BY-SA 3.0, Author: Andreas Kraska