Abstract: Four natural lactylates of chlorinated fatty acids, chlorosphaerolactylates A−D (1−4), were isolated from the methanolic extract of the cyanobacterium Sphaerospermopsis sp. LEGE 00249 through a combination of bioassay-guided and MS guided approaches. Compounds 1−4 are esters of (mono-, di-, or tri)chlorinated lauric acid and lactic acid, whose structures were assigned on the basis of spectrometric and spectroscopic methods inclusive of 1D and 2D NMR experiments. High-resolution mass spectrometry data sets also demonstrated the existence of other minor components that were identified as chlorosphaero(bis)- lactylate analogues. The chlorosphaerolactylates were tested for potential antibacterial, antifungal, and antibiofilm properties using bacterial and fungal clinical isolates. Compounds 1−4 showed a weak inhibitory effect on the growth of Staphylococcus aureus S54F9 and Candida parapsilosis SMI416, as well as on the biofilm formation of coagulase-negative Staphylococcus hominis FI31

Ignacio Gutiérrez-Del-Río, Nelly Brugerolle de Fraissinette, Raquel Castelo-Branco, Flavio Oliveira, João Morais, Saúl Redondo-Blanco, Claudio J. Villar, María José Iglesias, Raquel Soengas, Virginio Cepas, Yuly López Cubillos, Giacomo Sampietro, Liliana Rodolfi, Felipe Lombó, Sara M. Soto González, Fernando López Ortiz, Vitor Vasconcelos, Mariana A Reis