Glycolipids from Ipomoea murucoides as modulators of antibiotic activity in multidrug-resistant strains

The CHCl₃-soluble extract from flowers of Ipomoea murucoides, through preparative scale recycling HPLC, yielded three new pentasaccharides of 11-hydroxyhexadecanoic acid, named murucoidins XVII-XIX, which were characterized by NMR and mass spectrometry. These compounds were tested for in vitro antibacterial and resistance modulating activity against Staphylococcus aureus, Escherichia coli Rosetta gami, and two nosocomial pathogens, Salmonella typhi and Shigella flexneri. They exerted a potentiation effect of the clinically useful antibiotics tetracycline, kanamycin, and chloramphenicol against the tested bacteria strains by increasing antibiotic susceptibility up to 16-fold at concentrations of 25µg/mL (Figure 1). Financial Support: Dirección General de Asuntos del Personal Académico, UNAM (IN217310) and CONACyT (101380-Q).

Fig.1: Modulation assay of tetracycline against S. flexneri.