Favolon

A new biologically active triterpenoid, favolon B (1), was isolated from fermentation broths of Mycena sp. strain 96180. Favolon B showed antifungal activities towards Botrytis cinerea, Mucor miehei, Paecilomyces variotii and Penicillium notatum. No activities were observed against bacteria and yeasts. The structure of favolon B was elucidated by spectroscopic techniques.

Eight previously undescribed compounds were isolated and characterised from the supernatant and mycelium of a culture of the basidiomycete Favolaschia calocera originating from Kakamega equatorial rainforest in Kenya. These were: 9- oxostrobilurins A, G, K and I and the four monochlorinated calocerins A, B, C and D. The calocerins extend our knowledge of halogenated compounds obtained from natural sources. Four further known compounds were also identified: strobilurin G, favolon, pterulinic acid and 2,3 -dihydro-1-benzoxepin derivative. The four oxostrobilurins exhibited prominent antifungal and cytotoxic activities while the four calocerins only showed cytotoxic activity.