Ethanolic extracts of aerial parts of the plants Echinacea angustifolia DC, Echinacea purpurea L. (Moench), Rudbeckia fulgida var. sullivantii, Boyton et Beadle, and Rudbeckia speciosa Wenderoth show immunomodulating activity. The mice were treated in vivo for 5 days and the activity was tested for
Thiarubrine A, a dithiacyclohexadiene polyine from the roots of Chaenactis douglasii, and a related dithiacyclohexadiene from Rudbeckia hirta exhibit strong light-independent antibacterial and antifungal activity. This activity is enhanced by exposure to visible light. Visible light also converts