Vol.:(0123456789) 1 3 Bioprocess and Biosystems Engineering https://doi.org/10.1007/s00449-019-02211-9 RESEARCH PAPER Antioxidant compounds extracted from Diaporthe schini using supercritical CO 2 plus cosolvent Barbara Vargas da Rosa 1  · Kátia Regina Kuhn 1  · Gustavo Andrade Ugalde 2  · Giovani Leone Zabot 3  · Raquel Cristine Kuhn 1 Received: 16 April 2019 / Revised: 6 September 2019 / Accepted: 8 September 2019 © Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract Endophytic fungi have been highlight in the production of secondary metabolites with diferent bioactive properties, such as in the production of the antioxidant compounds. Therefore, the objective of this work was the extraction of the antioxidant compounds from the biomass of Diaporthe schini using supercritical carbon dioxide (CO 2 ) without and with ethanol as cosolvent. The biomass was produced by submerged fermentation and the parameters evaluated in the extraction process were: pressure (150–250 bar), temperature (40–60 ºC) and cosolvent [biomass: cosolvent ratio, 1:0, 1:0.75 and 1:1.5 (w/v)]. Extraction yield, antioxidant activity and chemical composition of the extracts were determined. The highest extraction yield (3.24 wt.%) and the best antioxidant activity against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical (96.62%) were obtained at 40 ºC, 250 bar and biomass:cosolvent ratio of 1:1.5 (w/v). The chemical compounds 1,4-diaza-2,5-dioxo- 3-isobutyl bicyclo[4.3.0]nonane and benzeneethanol identifed in GC/MS could be responsible for the antioxidant activity found in this study. Graphic abstract 0 5 10 15 20 25 30 35 0.0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0 5 10 15 20 25 30 35 40 45 S/F (g solvent/g feed) Yield (wt.%) Extract (g) Time (min) With co-solvent Without co-solvent Diaporthe schini (fungus) Extract Submerged fermentation Lyophilized biomass Supercritical extraction CO 2 CO 2 + ethanol Antioxidant compounds Keywords Submerged fermentation · Diaporthe schini · Supercritical CO 2 extraction · Cosolvent · Antioxidant activity * Raquel Cristine Kuhn raquel.kuhn@ufsm.br Extended author information available on the last page of the article