Identification of Asparagopsis armata‐associated bacteria and characterization of their bioactive potential

Macroalgae‐associated bacteria have already proved to be an interesting source of compounds with therapeutic potential. Accordingly, the main aim of this study was to characterize Asparagopsis armata‐associated bacteria community and evaluate their capacity to produce substances with antitumor and antimicrobial potential. Bacteria were selected according to their phenotype and isolated by the streak plate technique. The identification was carried out by the RNA ribosomal 16s gene amplification through PCR techniques. The antimicrobial activities were evaluated against seven microorganisms (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella enteritidis, Staphylococcus aureus, Saccharomyces cerevisiae, Candida albicans) by following their growth through spectrophotometric readings. Antitumor activities were evaluated in vitro on human cell lines derived from hepatocellular (HepG‐2) and breast carcinoma (MCF‐7) using the MTT method. The present work identified a total of 21 bacteria belonging to the genus Vibrio, Staphylococcus, Shewanella, Alteromonadaceae, Bacillus, Cobetia, and Photobacterium, with Vibrio being the most abundant (42.86%). The extract of Shewanella sp. ASP 26 bacterial strain induced the highest antimicrobial activity, namely against Bacillus subtilis and Staphylococcus aureus with an IC50 of 151.1 and 346.8 μg/mL, respectively. These bacteria (Shewanella sp.) were also the ones with highest antitumor potential, demonstrating antiproliferative activity on HepG‐2 cells. Asparagopsis armata‐associated bacteria revealed to be a potential source of compounds with antitumor and antibacterial activity.

Description

FP7 Food, Agriculture and Fisheries, Biotechnology, Grant/Award Number: 265896; Fundação para a Ciência e a Tecnologia, Grant/Award Number: PTDC/MAR‐BIO/6149/2014, SAICTPAC/0019/2015 ‐ LISBOA‐01‐0145‐ FEDER‐016405, SFRH/BD/103255/2014, SFRH/BD/120250/2016, SFRH/ BD/96203/2013, SFRH/BD/97764/2013 and UID/MAR/04292/2019; Centro 2020 program, Portugal 2020, European Union, European Regional Development Fund, Grant/Award Number: Centro‐01‐0145‐ FEDER‐000018

Keywords

Algae Antimicrobial Antitumor Epiphytic bacteria, Marine compounds Marine symbiosis

URI

http://hdl.handle.net/10400.8/5023

Citation

Horta, A., Alves, C., Pinteus, S., Lopes, C., Fino, N., Silva, J., Ribeiro, J., Rodrigues, D., Francisco, J., Rodrigues, A., & Pedrosa, R. (2019). Identification of Asparagopsis armata-associated bacteria and characterization of their bioactive potential. MicrobiologyOpen, 8(11), e00824. https://doi.org/10.1002/mbo3.824