Abstract
Two glucosides to enhance histamine release from rat peritoneal mast cells were isolated from rhizomes of bracken fern (Pteridium aquilinum (L.) Kuhn). by column chromatography on Sephadex LH-20 and droplet counter-current chromatography, and named braxin A1 and A2. They were β-glucopyranosides with an aromatic structure in the aglycone moiety. They were appreciably unstable in activity and chemical structure, and were different from the active glucoside in the young fronds. Braxin A1 and A2 may well be identical with the toxic principles responsible for the bracken poisoning.
