Exploring the Antibacterial and Antifungal Potential of Jellyfish-Associated Marine Fungi by Cultivation-Dependent Approaches

PLoS One. 2015 Dec 4;10(12):e0144394. doi: 10.1371/journal.pone.0144394. eCollection 2015.

Abstract

Fungi isolated from marine invertebrates are of considerable importance as new promising sources of unique secondary metabolites with significant biomedical potential. However, the cultivable fungal community harbored in jellyfish was less investigated. In this work, we seek to recover symbiotic fungi from different tissues of jellyfish Nemopilema nomurai. A total of seven morphotypes were isolated, which were assigned into four genera (Aspergillus, Cladosporium, Purpureocillium, and Tilletiopsis) from two phyla (Ascomycota and Basidiomycota) by comparing the rDNA-ITS sequences with the reference sequences in GenBank. The most fungi were found in the inner tissues of subumbrella. Two of the cultivation-independent procedures, changing media type and co-cultivation, were employed to maximize the complexity of metabolites. Thus, thirteen EtOAc gum were obtained and fingerprinted by High Performance Liquid Chromatography (HPLC) equipped with a photodiode array (PDA) detector. Antibacterial and antifungal activities of these complex mixtures were tested against a panel of bacterial and fungal pathogens. The antimicrobial results showed that all of the 13 EtOAc extracts displayed different levels of antibacterial activity, three of which exhibited strong to significant antibacterial activity to the bacterial pathogens Staphylococcus aureus and Salmonella entrica. Antifungal activity indicated that the EtOAc extracts from pure culture of Aspergillus versicolor and co-culture of A. versicolor and Tilletiopsis sp. in rice media were promising for searching new compounds, with the maximal mycelial growth inhibition of 82.32% ± 0.61% for Rhizoctonia solani and 48.41% ± 11.02% for Botrytis cinerea at 200 μg/ml, respectively. This study is the first report on the antibacterial and antifungal activity of jellyfish-associated fungi and allows the first sight into cultivable fungal community residing in jellyfish. Induced metabolites by cultivation-dependent approaches provides a new reservoir for drug discovery from jellyfish-derived fungi.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Ascomycota* / growth & development
  • Ascomycota* / isolation & purification
  • Basidiomycota* / growth & development
  • Basidiomycota* / isolation & purification
  • Rhizoctonia / growth & development*
  • Salmonella enterica / growth & development*
  • Scyphozoa / microbiology*
  • Staphylococcus aureus / growth & development*

Grants and funding

The authors gratefully acknowledge financial grants: the National Key Technologies R&D Program (2011BAE06B04), the National Natural Science Foundation of China (41376004, 41406152), and the Public Science and Technology Research Funds Projects of Ocean (201305016-2). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.