Abstract
The British moth Eana incanana (Tortricidae) has been found to selectively metabolize the glycosidase inhibitor 2R, 3R, 4R, 5R-2,5-dihydroxymethyl-3,4-dihydroxypyrrolidine (DMDP), whereas it excretes related alkaloids from Hyacinthoides non-scripta (Hyacinthaceae). Very few native animals feed on H. non-scripta, but the larvae of E. incanana are specialized herbivores feeding just on the buds and flowers destroying the ovary. DMDP is the major glucosidase inhibitor of H. non-scripta and the moth may overcome inhibition of digestive glucosidases by metabolizing the DMDP. The glucosidase enzymes of the caterpillar are inhibited by DMDP. The caterpillar excretes the other glycosidase inhibitors produced by this plant and the frass has increased concentrations of these alkaloids.