On the occurrence of the contact allergen primin and other quinoid compounds in species of the family of primulaceae.

82 different species of the Primulacea family have been investigated by a screening test. In 16 Primula species and 4 species of other genera the strong contact allergen primin could be detected by the Craven-test. Extracts of only 12 plants gave no color reaction. In the remaining species other quinoid components were detectable. From 4 species new quinoid substances were isolated. Primin itself was obtained from Primula elatior and from the petals (corollas) of Primula obconica. The results indicate that the presence of primin and other quinones is determined by their origin and seasonal variations. It is supposed that some of the detected quinones may function as allergens and therefore may be responsible for the contact dermatitis described in the literature due to several Primula species and some other species of the same family. Some indications point to the suspicion that primin occurs in the plant as a glycoside which is separated by extraction treatment to give its quinole and an unknown substance. The quinole oxidizes then to the quinhydrone and finally to primin itself.