Resumo

The need for new and useful compounds to provide assistance and relief in all aspects of the human condition is ever growing. There is a general call for new antibiotics, chemotherapeutic agents and agrochemicals that are highly effective, possess low toxicity and have a minor environmental impact. Microorganisms are the largest reservoir of potentially valuable natural compounds. Endophytes such as fungi and bacteria that intracellularly colonize plant tissues are known to be a rich source of novel compounds, including anticancer agents, antibiotics, antivirals, antioxidants and immunomodulatory compounds, in addition to being a source of polyunsaturated fatty acids. We further investigated the antibacterial and antioxidant activities of this fungal isolate in addition to the possible production of fatty acids with biotechnological importance. The Antarctic endophytic fungus (strain ITA1-CCMA 952) was isolated from the moss Schistidium antarctici found in Admiralty Bay, King George Island, Antarctic. Strain ITA1-CCMA 952 was assigned to the genus Mortierella by phylogenetic analysis based on 18S rRNA gene sequences. This strain produces high levels of polyunsaturated fatty acids, including y-linolenic acid and arachidonic acid, which combined represents 48.3% of the total fatty acid content. Fungal extracts demonstrated strong antioxidant activity with the IC50 value of 48.7 μg mL-1 and also a strong antibacterial activity, mainly against the following bacteria: Escherichia coli, with a MIC of 26.9 µg mL-1 and Pseudomonas aeruginosa and Enterococcus faecalis, both with a MIC of 107 µg mL-1. A GC-MS analysis of the chloroform fraction obtained from the crude extract revealed the presence of potential antimicrobials (Pyrrolo[1,2-a]pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl) and Pyrrolo[1,2-a]pyrazine-1,4-dione, hexahydro-3-(phenylmethyl)) as the major compounds. Therefore, the Mortierella sp. strain ITA1-CCMA 952 is a promising fungus for the biotechnological production of antibiotics, antioxidant substances and PUFAs (Polyunsaturated Fatty Acids). This study highlights the need for more research in extreme environments, such as Antarctica.