Historical and traditional medical applications of Carlina acaulis L. - A critical ethnopharmacological review

The genus Carlina (Asteraceae) comprises approx. 30 plant species growing in Europe and Asia. Carlina acaulis L. was widely used as medicine, especially in Germany and Poland. The plant root was applied e.g. to treat various skin diseases and as a diaphoretic, diuretic, and anthelmintic agent. At the end of the 19th century, the medicinal use of the plant ceased though C. acaulis roots are still used in folk medicine, especially in rural areas of the Balkans where the plant grows in the wild.The aim of this review is to compile historical and current ethnomedical uses of C. acaulis and compare these applications with the results of modern chemical and pharmacological research of this plant. This analysis may give a lead for further research on this old, almost forgotten medicinal plant.Historical data on the medicinal application of C. acaulis over many centuries were collected. The historical uses were compared with the contemporary indications. The present day knowledge on the chemistry and biological activity of C. acaulis is also reviewed. This information is compared with the ethnopharmacological information.Plants from the genus Carlina were already described by Theophrastus of Eresus, Dioscorides, Pliny the Elder, and Galen of Pergamum. Carlinae radix was still featured in Renaissance botanical books and in official pharmacopoeias, but disappeared from the scene in the 19th century. The present day information on the phytochemistry and pharmacological activity of these plants is limited. There are some data on the occurrence of common plant ingredients such as essential oil, flavonoids, phenolic acids, triterpenes, inulin, and fatty acids. However, most concern the green parts of the plant. Its medicinal use remains poorly understood, as there are only very limited results of in-vitro studies on the roots.The historical uses of the plant can still be found in rural areas. Yet, detailed phytochemical and pharmacological research is needed to evaluate the effectiveness and safety of the medical use of Carlina acaulis.