Modulation of drug resistance in Staphylococcus aureus by 132-hydroxy-(132-R/S)-pheophytin isolated from Sargassum polyceratium

Publication date: Available online 30 January 2020Source: Microbial PathogenesisAuthor(s): Suellen Menezes-Silva, Narlize Silva Lira, Yuri Mangueira do Nascimento, Roseana Ramos, Celidarque da Silva Dias, Josean Fechine Tavares, Marcelo Sobral da Silva, George Emmanuel Cavalcanti de Miranda, José Maria Barbosa Filho, José Pinto de Siqueira-JuniorAbstractEfflux pumps are integral parts of the bacterial plasma membrane that are responsible for many cases of antibiotic resistance. Modulators of drug resistance are regarded as the most suitable new antibacterial therapies. We evaluated the extracts of Sargassum polyceratium and the isolated compound pheophytin (Sp-1) for antibiotic modifying activity in strains of Staphylococcus aureus with efflux pump. The minimum inhibitory concentrations (MICs) for norfloxacin, tetracycline and erythromycin were determined by the microdilution broth method, in the absence and presence of the extract at a sub-inhibitory concentration (MIC/4). The extracts and isolated compounds showed no significant antimicrobial activity, but they changed the antibiotic activity, decreasing bacterial resistance by 2 to 4x. Using a checkerboard method, it was also possible to observe the synergistic effect (ΣFIC ≤ 0.5) between Sp-1 and the antibiotics erythromycin and norfloxacin. The results indicate that the seaweed Sargassum polyceratium and pheophytin are potential sources of an antibiotic adjuvant that modulates bacterial resistance, acting as a p...
Source: Microbial Pathogenesis - Category: Infectious Diseases Source Type: research