Isolation of an active glucoside in bracken fern, Pteridium aquilinum

An active glucoside that enhanced release of histamine from rat peritoneal mast cells was isolated from a toxic fraction of bracken fern, Pteridium aquilinum, by partition column chromatography on Sephadex G-25. It was a yellowish amorphous powder on freeze-drying, readily soluble in water or ethanol, and insoluble in ether. It was hydrolysed with beta-glucosidase to release D-glucose. It was assumed to be a kind of beta-glucopyranoside with a carbocyclic structure in the aglycone moiety.