Isolation of a fungus from a hydrocarbon contaminated Antarctic soil and characterization of it exudate.

RUBERTO L; LEVIN G; HERNANDEZ E; STICHEL A; BLANCO M; MAC CORMACK W

Potrero de los Funes, San Luis

Congreso; XLVII Reunión Anual de la SAIB; 2011

SAIB

A psychrotolerant fungus was isolated from hydrocarbon-contaminated soils from Jubany station. After 30 days of growth at 15°C, the isolate produce an intense yellowish-colored exudate which completely dyed the culture medium (potato-dextrose–chloranphenicol agar). The exudate can be collected as small drops from both, the surface of colonies and the Petri dish. Based on previous reports, it was supposed that the molecule responsible of the yellow color could be an anthraquinone-related compound. In order to find out the composition of the exudate, several analytical procedures were applied (thin layer chromatography TLC, isoelectrofocusing, UV spectra analysis and reverse-phase high performance liquid chromatography). The results showed that the exudate is composed by at least four components, one of them exhibiting high polarity. The UV analysis suggested that two different molecules are responsible of the yellow color. Reverse-phase TLC evidenced the presence of two compounds with high absorption at near UV (366 nm) and isolectrofocusing showed that at least one of these compounds is a protein with isoelectric point near 3. Colonies of the fungus showed to have antifungal properties, inducing an evident inhibition halo when it was cultivated with other fungus in the same plate. The antifungal compound could represent a novel molecule with clinical or biotechnological potential uses.