Diversity and bioprospecting of fungal communities associated with endemic and cold-adapted macroalgae in Antarctica

Abstract

We surveyed the distribution and diversity of fungi associated with eight macroalgae from Antarctica and their capability to produce bioactive compounds. The collections yielded 148 fungal isolates, which were identified using molecular methods as belonging to 21 genera and 50 taxa. The most frequent taxa were Geomyces species (sp.), Penicillium sp. and Metschnikowia australis. Seven fungal isolates associated with the endemic Antarctic macroalgae Monostroma hariotii (Chlorophyte) displayed high internal transcribed spacer sequences similarities with the psychrophilic pathogenic fungus Geomyces destructans. Thirty-three fungal singletons (66%) were identified, representing rare components of the fungal communities. The fungal communities displayed high diversity, richness and dominance indices; however, rarefaction curves indicated that not all of the fungal diversity present was recovered. Penicillium sp. UFMGCB 6034 and Penicillium sp. UFMGCB 6120, recovered from the endemic species Palmaria decipiens (Rhodophyte) and M. hariotii, respectively, yielded extracts with high and selective antifungal and/or trypanocidal activities, in which a preliminary spectral analysis using proton nuclear magnetic resonance spectroscopy indicated the presence of highly functionalised aromatic compounds. These results suggest that the endemic and cold-adapted macroalgae of Antarctica shelter a rich, diversity and complex fungal communities consisting of a few dominant indigenous or mesophilic cold-adapted species, and a large number of rare and/or endemic taxa, which may provide an interesting model of algal-fungal interactions under extreme conditions as well as a potential source of bioactive compounds.

Fungal Community Structure of Macroalga Ulva Intestinalis Revealed by Miseq Sequencing

“…In addition, Basidiomycota were the second dominant phylum in EU and LU samples representing about 15.51% and 19.14 % of classified fungi, respectively. This results is agreed with other studies where Ascomycota were the most dominant fungi associated with antarctica algae (Godinho et al, 2013) and marine organism (algae, ascidian and sponge) of north coast of Sao Paulo, Brazil (Menezes et al, 2010). Figure 3B presenting the population structure of fungi at class levels.…”

“…Postharvest and Biotech. 12 (3) The abundance and diversity of classified fungi in this study were higher than fungi associated with antarctic algae, which was only 21 genera revealed (Godinho et al, 2013). Furthermore alga Fucus serratus consist of 25 genera, which represented 2 phyla (Ascomycota and Zygomycota) (Zuccaro et al, 2008).…”

“…Algae have been well-known as host of abundant marine microorganism like bacteria and fungi (Godinho et al, 2013;Wichard et al, 2015), that may play an important rules in the ecosystem and bring the benefit for the growth of that algae (Burke, Thomas, Lewis, Steinberg, & Kjelleberg, 2011;Matsuo, Imagawa, Nishizawa, & Shizuri, 2014;Richards, Jones, Leonard, & Bass, 2012). Furthermore, the biochemical and physical processes which occur in the algal thallus surface are likely to play a role in structuring both qualitatively and quantitatively of the microbial community associated with algae (Egan et al, 2013;Maximilian et al, 1998;Tujula et al, 2010).…”

“…Several studies about fungi associated with algae have been conducted which most of them used culture dependent techniques (Gnavi et al, 2016;Loque et al, 2010;Godinho et al, 2013). The results showed that culture dependent technique only revealed less than 1% of fungal community (Handelsman, 2005).…”

“…The interaction of bacteria-algae (Egan et al, 2013) and the fungal community of U. intestinalis ((Godinho et al, 2013) have been studied using culture dependent method. Recently, the Illumina MiSeq is employed and recommended for analyzing microbial community of environmental samples.…”