BIOLOGICALLY-ACTIVE SECONDARY METABOLITES OF ENDOPHYTIC PEZICULA SPECIES

Endophytic Pezicula strains were isolated from living branches of ten deciduous and coniferous trees and tested for their fungicidal, algicidal and antibacterial activities. From the three biologically active strains that were selected for fermentation, five substances were isolated and their structures determined as (R)-mellein, (-)-mycorrhizin A, 2-methoxy-4-hydroxy-6-methoxymethylbenzaldehyde, (+)-cryptosporiopsin and 4-epi-ethiosolide. They are strongly fungicidal and herbicidal, to a lesser extent algicidal and antibacterial. The synthesis of these metabolites in 85 isolates was dependent on conditions of culture and was also found to be taxonomically significant. The potential role of these substances is discussed with respect to mutualism and parasitism.