Toxicity of Saponins in Alfombrilla (Drymaria arenarioides)

Abstract

Alfombrilla (Drymaria arenarioides H.B.K.) is a highly toxic short-lived perennial of the Caryophyllaceae family found in Mexico. The species has gradually spread northward through Chihuahua and Sonora and now threatens to invade the southwestern United States. Alfombrilla was analyzed for seven common poisonous compounds. Of these, only saponins, which assayed 3.0% of the plant dry weight, were present at toxic levels. Sheep were killed when fed dried alfombrilla at 0.5% of body weight and with saponin extracted from an equivalent weight of plant. When 1-week-old chicks were fed alfombrilla at 2 to 3% of body weight and with an equivalent weight of pure saponin extracted from the plant, they were acutely poisoned. Thin-layer chromatography showed that six saponins were present in alfombrilla.