Isolation of fungi associated with macroalgae from maritime Antarctica and their production of agarolytic and carrageenolytic activities

Antarctica includes different pristine environments dominated by extremophile microbial communities. Despite the ecological role importance of Antarctic microorganisms, some of them can represent interesting sources of bioproducts with potential industrial application. In the present study, we analysed the agarolytic and carrageenolytic activities of algicolous fungi from seven different macroalgal species of maritime Antarctica. After a selective isolation process, 44 fungal isolates were recovered and identified by biology molecular methods as belonging to the genera Antarctomyces, Beauveria, Cladosporium, Coprinellus, Doratomyces, Leucosporidiella, Metschnikowia, Penicillium, and Pseudogymnoascus. Rhodophyta macroalgae sheltered the fungi with the best potential for agarolytic and carrageenolytic activities. Penicillium chrysogenum, Penicillium sp., and Cladosporium sp. 2 simultaneously displayed the best carrageenolytic and agarolytic activities. Our results indicated that the Antarctic macroalgae shelter saprobe fungi that produce enzymes with the potential to degrade algal biomass and might release essential nutrients into the Antarctic Ocean. These agarolytic and/or carrageenolytic Antarctic fungi may also be useful in further industrial processes involving the biological extraction of agar and carrageenan, or their byproducts, to be used as substrates of third-generation bioethanol.