Chrysanthemum allergy III. Identification of the allergens.

Experimental and chemical studies in guinea pigs on contact allergy caused by Chrysanthemum indicum L. (Chrysanthemum of the florists) led to the isolation of several sesquiterpene lactones. From the crude extract of dried flowers 12 fractions were obtained of which four gave strong reactions on epicutaneous application to guinea pigs sensitized with an extract of C. indicum L. One of these allergens was identified as a sesquiterpene lactone of the guaianolide type. It is identical to Arteglasin-A derived from Artemisia douglasiana Bess. The occurrence of Arteglasin-A in Chrysanthemum indicum L. as well as its allergenic properties are described forthe first time. These findings give rise to the assumption that the other, as yet unidentified sesquiterpene lactones of this flower also belong to the guaianolide type.