Neofiscalin A and fiscalin C are potential novel indole alkaloid alternatives for the treatment of multidrug-resistant Gram-positive bacterial infections.
Ten indole alkaloids were obtained from the marine sponge-associated fungus Neosartorya siamensis KUFA 0017. We studied the antimicrobial properties of these and of three other compounds previously isolated from the soil fungus N. siamensis KUFC 6349. Only neofiscalin A showed antimicrobial activity against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE); with a minimum inhibitory concentration (MIC) of 8 μg mL(-1) against both strains. Another compound, fiscalin C, presented synergistic activity against MRSA when combined with oxacillin, although alone showed no antibacterial effect. Moreover, neofiscalin A, when present at sub-MICs, hampered the ability of both MRSA and VRE strains to form a biofilm. Additionally, the biofilm inhibitory concentration values of neofiscalin A against the MRSA and VRE isolates were 96 and 80 μg mL(-1), respectively. At a concentration of 200 μg mL(-1), neofiscalin A was able to reduce the metabolic activity of the biofilms by ∼50%. One important fact is that our results also showed that neofiscalin A had no cytotoxicity against a human brain capillary endothelial cell line.
Department of Aquatic production, Abel Salazar Institute for the Biomedical Sciences, University of Porto, Jorge Viterbo Ferreira Street no. 228, 4050-313 Porto, Portugal Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Bragas Street no. 289, 4050-123 Porto, Portugal.
Lucinda J
LJ
Bessa
Department of Aquatic production, Abel Salazar Institute for the Biomedical Sciences, University of Porto, Jorge Viterbo Ferreira Street no. 228, 4050-313 Porto, Portugal Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Bragas Street no. 289, 4050-123 Porto, Portugal.
Suradet
S
Buttachon
Department of Plant Pathology, Faculty of Agriculture, Kasetsart University, 50 Ngam Wong Wan Road Chatuchak, 10900 Bangkok, Thailand.
Tida
T
Dethoup
Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Bragas Street no. 289, 4050-123 Porto, Portugal Research Centre on Health and Environment, School of Allied Health Sciences, Polytechnic Institute of Porto, Valente Perfeito Street no. 322, 4400-330 Vila Nova de Gaia, Portugal.
Rosário
R
Martins
Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Bragas Street no. 289, 4050-123 Porto, Portugal Department of Biology, Faculty of Sciences, University of Porto, Campo Alegre Street no. 1021/1055, 4169-007 Porto, Portugal.
Vitor
V
Vasconcelos
Department of Aquatic production, Abel Salazar Institute for the Biomedical Sciences, University of Porto, Jorge Viterbo Ferreira Street no. 228, 4050-313 Porto, Portugal Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Bragas Street no. 289, 4050-123 Porto, Portugal.
Anake
A
Kijjoa
Department of Aquatic production, Abel Salazar Institute for the Biomedical Sciences, University of Porto, Jorge Viterbo Ferreira Street no. 228, 4050-313 Porto, Portugal Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Bragas Street no. 289, 4050-123 Porto, Portugal pmcosta@icbas.up.pt.
Paulo
P
Martins da Costa
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects; D055808:Drug Discovery; D024901:Drug Resistance, Multiple, Bacterial; D013293:Enterococcus faecalis / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology; D006801:Humans; D026121:Indole Alkaloids / Q000302:isolation & purification / Q000494:pharmacology* / Q000627:therapeutic use; D007211:Indoles / Q000494:pharmacology* / Q000627:therapeutic use; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D055326:Neosartorya / Q000737:chemistry / Q000378:metabolism; D010068:Oxacillin / Q000494:pharmacology; D011799:Quinazolines / Q000494:pharmacology* / Q000627:therapeutic use
D000900:Anti-Bacterial Agents; D026121:Indole Alkaloids; D007211:Indoles; D011799:Quinazolines; C081409:fiscalin C; D010068:Oxacillin
Neosartorya siamensis; antimicrobial activity; fiscalin C; multidrug-resistant Gram-positive; neofiscalin A