Antibacterial Activity and Mode of Action of (+)-2,2'-Epicytoskyrin A

Abstract

Antibacterial activity of (+)-2,2'-epicytoskyrin A, a main metabolite from culture of fungal endophyte Diaporthe sp. GNBP-10, was investigated against several strains of Gram-positive, Gram-negative bacteria, and one strain of Mycobacterium smegmatis. (+)-2,2'-Epicytoskyrin A exhibited prominent activity against Staphylococcus aureus BCC 1452 with minimum inhibitory concentration (MIC) value of 0.06 μg mL^-1. The effect of (+)-2,2'-epicytoskyrin A treatment to S. aureus, resulted in alteration of bacterial cell membrane with an increase of cation efflux, while the cytoplasmic content was not leaked out and finally resulted in cell damage.