... diketopiperazines and macrocyclic lactones are the active secondary metabolites. The species and the biological activity of ... Some L, L-diketopiperazines have recently been known as quorum-sensing bacterial sensors [21, 22], which are used by Gram- ... S. P. B. Ovenden, G. Sberna, R. M. Tait et al., "A diketopiperazine dimer from a marine-derived isolate of Aspergillus niger," ... X. Fu, M. L. G. Ferreira, F. J. Schmitz, and M. Kelly-Borges, "New diketopiperazines from the sponge Dysidea chlorea," Journal ...