Antimicrobial Effects of Violacein against Planktonic Cells and Biofilms of Staphylococcus aureus oleh Andressa H. M. Batista, Anne C. D. Moreira, Rafael M. de Carvalho, Gleilton W. P. Sales, Patrícia C. N. Nogueira, Thalles B. Grangeiro, Suelen C. Medeiros, Edilberto R. Silveira, Nádia A. P. Nogueira