Culturable fungi from dredged and marine sediments from six ports studied in the framework of the SEDITERRA Project

Purpose Mycological characterisation of marine and dredged sediments consists of the isolation of vital and culturable fungal strains as well as their identification and analysis, in order to increase knowledge of sediment mycobiota and isolated species that can be employed in biotechnological processes. Our study undertook the mycological characterisation of sediments from six different port environments: marine bottom sediments from the ports of Genoa (Liguria, Italy) and Centuri (Corsica, France), dredged sediments (sediments removed from the sea bottom) from landfill sites (contaminated land sites where dredged sediments are deposited) of the ports of Leghorn (Tuscany, Italy) and Cagliari (Sardinia, Italy), bottom muds from the brackish environment of the navigable Navicelli Canal of Pisa (Tuscany, Italy) and dredged marine sediments from a temporary storage site in the port of Toulon (Var, France). Materials and methods At each site, 30 kg of sediment was sampled for physical, chemical and mycological analyses. They were analysed in terms of grain size composition, organic and inorganic content, metal concentration and hydrocarbon and polychlorinated biphenyl concentration. Fungi were then isolated from sediments by a modified dilution plate technique from 1:10 up to 1:100. Fungal identification was carried out using a morphological and molecular polyphasic approach. Results and discussion Forty-six fungal species belonging to 20 genera were isolated. The highest biodiversity was found in Leghorn (14 species), Genoa (11) and Cagliari (11) sediments, while very low numbers of species were isolated from the ports of Centuri (3) and Toulon (4). Similarly, the number of colony-forming units (CFUs), calculated on the dry weight of the sediments, followed this order: Genoa (3,765 CFUs*g(-1)) > Leghorn (1,370 CFUs*g(-1)) > Pisa (1,190 CFUs*g(-1)) > Cagliari (410 CFUs*g(-1)) > Toulon (380 CFUs*g(-1)) > Centuri (220 CFUs*g(-1)). The most represented genera were Penicillium, Aspergillus and Trichoderma. Some halotolerant species known for their biotechnological properties were isolated: Emericellopsis maritima, Cladosporium halotolerans and Aspergillus micronesiensis. A potential marine pathogenic fungus was found: Aspergillus sydowii. Conclusions This work increased knowledge of fungi from marine and dredged sediments in six Mediterranean ports in the framework of the SEDITERRA Project.

Automated summary

The study conducted mycological characterization of marine and dredged sediments from six Mediterranean ports, identifying 46 fungal species belonging to 20 genera. The research discovered several halotolerant fungal species with biotechnological properties, as well as a potential marine pathogenic fungus.