Tubastraea coccinea : A Non-Indigenous Coral (Cnidaria, Scleractinia) Collected at Arvoredo Island, South of Brazil with Potential MRSA and VRE Antimicrobial Activity

Abstract

Bacterial infection is considered to be one of the most critical health issues of the world. It is es-sential to overcome this problem by the development of new drugs. Marine organisms as corals, sponges, seaweeds, and other are an incredible source of novel pharmacologically active com-pounds. Herein, the antimicrobial activity (extract/fractions) of the invasive stony coral Tuba-straea coccinea was evaluated by the disk diffusion method against 21 microbial strains (ATCC and clinical strains). Micro broth dilution was used to determinate the MIC of the fractions that showed antimicrobial activity by the disk diffusion method. Bioautography assay was also performed. Our results showed that the n-butanol (BF) and aqueous fractions (AF) showed activity against ATCC strains Staphylococcus aureus (MIC 31.25 and 250 μg/mL), Salmonella typhimurium (MIC 125 and 500 μg/mL), Escherichia coli (MIC 62.5 and 500 μg/mL) and Pseudomonas aeruginosa (MIC 62.5 É. M. Bianco et al. 335 and 500 μg/mL), respectively. Moreover, BF fraction was also effective against the clinical strains S. aureus (MIC 62.5 μg/mL), Klebsiella pneumoniae Carbapenemase—KPC (MIC 125 μg/mL), Methi-cillin-Resistant Staphylococcus aureus—MRSA (MIC 125 μg/mL) and Vancomycin-Resistant Ente-rococcus faecalis—VRE (MIC 62.5 μg/mL). The ratio MBC/MIC reinforces the bactericidal profile of BF fraction. The bioautography assay of BF fraction showed the presence of antimicrobial compo-nents at Rf 0.55.