Mechanism of the lethal effect of Riparin E against bacterial and yeast strains

• Published in: Microbial pathogenesis 2021-08, Vol.157, p.104968-104968, Article 104968
• Main Authors: Muratori Costa, Luciana, Nascimento de Sousa, Jonas, Braz, Débora Cavalcante, Lima Ferreira, Josie Haydee, Sampaio Nogueira, Carlos Emídio, Barbosa-Filho, José Maria, de Sousa Lima-Neto, José, Chavez Gutierrez, Stanley Juan, de Araújo Abi-chacra, Érika, Barreto, Humberto Medeiros
• Format: Article
• Language: English
• Subjects: Antimicrobial activity; Bacterial infections; Fungi infections; Riparins
• ISSN: 0882-4010; 1096-1208
• DOI: 10.1016/j.micpath.2021.104968

Riparins are alkamides naturally found in the fruits of Aniba riparia (Nees) Mez, but currently synthetic molecules as Riparin E (Rip-E) can be obtained. Potential biological of Rip-E as schistosomicidal agent against Schistosoma mansoni worms, as well as against Staphylococcus aureus strains has already been described. However, the mechanism of action related to antimicrobial activity of Rip-E against bacterial or fungi species has not yet been reported. This study had as objective to evaluate the Rip-E antimicrobial activity against Gram-positive and Gram-negative bacteria, as well as against yeast species of clinical importance. Minimal inhibitory concentrations of the compound against bacterial and yeast strains were determined by microdilution method. To verify if a possible lethal effect caused by Rip-E were related to plasma membrane damage, microbial cells treated with Rip-E were stained with 7-aminoactinomycin D (7-AAD) and analyzed by flow cytometry. Rip-E showed a bactericide effect against Gram-positive species S. aureus and S. epidermidis, as well as, against Gram-negative species Escherichia coli and Salmonella enterica Typhimurium, but was inactive against Pseudomonas aeruginosa. Moreover, Rip-E showed activity against fungi species Candida albicans and C. tropicalis. S. aureus, E. coli and C. albicans cells treated with Rip-E were marked with 7-aminoactinomycin D (7-AAD) indicating that Rip-E can cause plasma membrane damage, acting as a potential microbicide agent for prevention or treatment of infectious diseases. [Display omitted] •Riparin E is a bactericide agent for some Gram-positive and Gram-negative bacteria.•Riparin E is a fungicide agent active against Candida spp.•Riparin E appear damages cell membrane of bacteria and fungi.