Potent Contact Allergen in the Rubber Plant Guayule ( Parthenium argentatum )

Abstract
Chemical and dermatotoxicological investigations of the natural and processed resin of the Mexican rubber plant, guayule (Parthenium argentatum), has established the presence of a sesquiterpene cinnamic acid ester (guayulin A) that is a potent elicitor of allergic contact dermatitis in experimental animals. The guayule contact allergen is comparable to the poison ivy skin allergens as an elicitor of dermatitis in sensitized guinea pigs.