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Fatty acids rich-oil was extracted from freeze-dried fungal biomass of Nigrospora sp. using ultrasound with ethanol as a cosolvent + supercritical CO2. The parameters of temperature (40–80 °C), pressure (15–25 MPa), ultrasound pre-treatment time (15–60 min), and the addition of ethanol (30–70 g/100 g biomass) were evaluated on the oil yield and composition. The best oil yield (3.94 wt.%) and total fatty acids (45.5 g/100 g oil) were obtained at 80 °C and 25 MPa with 50 wt.% ethanol after pre-treating the biomass for 60 min using 132 W of ultrasound power at 40 kHz. The main fatty acids were oleic, palmitic, linoleic, elaidic and palmitoleic acids. The combination of CO2 under supercritical conditions and ultrasound with ethanol as a pre-treatment of the biomass from Nigrospora sp. concentrated up to 4.0 times fatty acids in the oil when compared to the Soxhlet technique, especially the unsaturated ones.

One hundred fifty fungal strains were isolated from the Pampa biome for production of polyunsaturated fatty acids (PUFA). Microbial oil was produced by submerged cultivation at 120 rpm, 28 ºC for 7 days. Seven strains showed the best results for lipids accumulation, and they were selected in order to evaluate the influence of the temperature (15 and 28 ºC) on the lipid production and profile. The fungus Nigrospora sp. produced the highest lipid level: at 28 ºC were produced 11.28% of lipids and 51.94% of PUFA and at 15 ºC were produced 6.02% of lipids and 42.39% of PUFA. Plackett Burman design was performed to investigate the main effects of the temperature (15-25 ºC), pH (4.0-6.0), agitation (120-200 rpm), corn steep liquor (5-15% (v/v)) and sucrose concentrations (60-180 g L-1). The highest PUFA production (55.75%) was observed at the lowest temperatures (15 ºC), whereas the maximum lipid production was 5.54% at 25 ºC.

A new hydroanthraquinone, nigrosporone A (1), and a new naturally occurring nigrosporone B (2), together with eleven known compounds, were isolated from an endophytic fungus, Nigrospora sp. BCC 47789. The structure of nigrosporone A was confirmed by X-ray crystallographic analysis. The absolute configurations of nigrosporone B were determined by the modified Mosher’s method. Nigrosporone B exhibited a broad range of biological activities including antimalarial, antitubercular, antibacterial and cytotoxic activities, while nigrosporone A and Fusaquinon A showed only cytotoxic activity.

One new hydroanthraquinone dimer with a rare C-9–C-7′ linkage, nigrodiquinone A (1), and four known anthraquinone monomers 2–5, were isolated from a fungus Nigrospora sp. obtained from the zoanthid Palythoa haddoni collected in the South China Sea. The structure of 1 was established through extensive NMR spectroscopy, and the absolute configuration was elucidated by comparing computed electronic circular dichroism (ECD) and optical rotations (OR) with experimental results. All the compounds were evaluated for antiviral activity, and 1 was also evaluated for antibacterial activity. Compound 4 displayed mild antiviral activity against coxsackie virus (Cox-B3) with the IC50 value of 93.7 μM, and 5 showed an IC50 value of 74.0 μM against respiratory syncytial virus (RSV).