Antimycobacterial and cytotoxicity activity of microcystins

• Published in: Journal of Venomous Animals and Toxins including Tropical Diseases
• Main Authors: Daniela Fernandes Ramos, Alexandre Matthiensen, Wilson Colvara, Ana Paula Souza de Votto, Gilma Santos Trindade, Pedro Eduardo Almeida da Silva, João Sarkis Yunes
• Format: Article in Journal/Newspaper
• Language: English
• Published: SciELO 2015
• Subjects: Mycobacteria; Antimycobacterial agents; Cytotoxic activity; Microcystins; Arctic medicine. Tropical medicine; RC955-962; Toxicology. Poisons; RA1190-1270; Zoology; QL1-991; Arctic
• Online Access: https://doi.org/10.1186/s40409-015-0009-8; https://doaj.org/article/ed71031f8206463fb40b114fd636bff0

Background The present work aimed to evaluate the antimycobacterial activity and cytotoxicity of Microcystis aeruginosa toxins, the MC-LR variant and purified extract of [D-Leu1] microcystin-LR. Methods The antimicrobial activity of M. aeruginosa extract and microcystin was evaluated by resazurin microtiter assay against Mycobacterium tuberculosis, M. terrae, M. chelonae and M. kansasii. The cytotoxicity assay was performed by trypan blue exclusion against the HTC cell line. Results Antimicrobial activity was observed in the hexanic extract of M. aeruginosa (RST 9501 strain) against M. tuberculosis, including sensitive and resistant strains with minimal inhibitory concentrations (MIC) between 1.93 μM and 0.06 μM. The high activity of M. aeruginosa hexanic extract could be attributed to the major presence of the toxins MC-LR and [D-Leu1] MC-LR that showed activity at MIC between 53 and 0.42 μM against tested mycobacterial strains. Even at the highest concentration tested, no toxicity of M. aeruginosa extracts was identified against HTC cells. Conclusions These preliminary results suggest that [D-Leu1] MC-LR is a promising candidate for the development of a new antimycobacterial agent.