Antibacterial activity and mode of action of (+)-2,2'-epicytoskyrin A

Antibacterial activity of (+)-2,2\'-epicytoskyrin A, a main metabolite from culture of fungal endophyteDiaporthe sp. GNBP-10, was investigated against several strains of Gram-positive, Gram-negative bacteria, andone strain of Mycobacterium smegmatis. (+)-2,2\'-Epicytoskyrin A exhibited prominent activity againstStaphylococcus aureus BCC 1452 with minimum inhibitory concentration (MIC) value of 0.06 μg mL-1. Theeffect of (+)-2,2\'-epicytoskyrin A treatment to S. aureus, resulted in alteration of bacterial cell membrane with anincrease of cation efflux, while the cytoplasmic content was not leaked out and finally resulted in cell damage.Key words: (+)-2,2\'-epicytoskyrin A, antibacterial activity, Diaporthe sp. GNBP-10, Uncaria gambier Microbiology Indonesia Tahun 2015 Vol. 9(1) : 35-43