A Strategy for Detecting Natural Anthelmintic Constituents of the Grassland Species Plantago lanceolata

A Strategy for Detecting Natural Anthelmintic Constituents of the Grassland Species Plantago lanceolata

A strategy to detect anthelmintic constituents in plantain (Plantago lanceolata) using a bioassay-driven purification approach was tested. Plantain consumed by cattle may control or reduce internal parasite titers, possibly due to the iridoid glucoside aucubin. Lyophilized, ground leaves of wild P. lanceolata were extracted with 95 % ethanol or boiling water containing calcium carbonate. Partially purified extracts (0 to 250 mg ml^-1), 5 μg ml^-1 of the anthelmintic levamisole, or 5 mg ml^-1 of aucubin were tested with sheathed bovine parasites (Ostertagia ostertagi). The percent moving worms was unchanged for water controls and reduced to 0 % for anthelmintic levamisole. Aucubin significantly reduced the number of swimming worms at day 2, but they returned to starting values at day 3. Extracts from tall fescue and white clover foliage did not show anthelmintic effects. Treatment of extract or aucubin with ß-glucosidase did not alter their activity. Beneficial anthelmintic action of ingested plantain is not due to aucubin.