Dactylarin, a new antiprotozoal antibiotic from Dactylaria lutea.

Our screening for new antiprotozoal antibiotics as described by Nemecet al.1* has revealed a very high incidence of cultures with antiprotozoal activity in the Fungi imperfecti. Nearly all species of the Fungi imperfecti tested are "predacious fungi" characterized by their ability to trap and kill nematodes and/or protozoa2), Dactylaria lutea Routien, obtained from the culture collection of the Centraalbureau voor Schimmelcultures in Baarn. The Netherlands, and previously reported to exhibit antiprotozoal activity1} was studied in more detail. Isolation and purification by chromatography using silica gel gave an active red crystalline substance which we call dactylarin. Onthe basis of physical and chemical data, the structure of dactylarin has been established. With regard to its physico-chemical characteristics and its biological properties, we conclude that dactylarin is a new antibiotic. In this paper, the fermentation, isolation procedure and characterization of dactylarin are reported.