A comparative study between conventional and non-conventional extraction techniques for the recovery of ergosterol from Agaricus blazei Murrill

Response surface methodology was applied to optimize the recovery of ergosterol from an agroindustrial residue of Agaricus blazei Murrill, by comparing conventional (heat-assisted extraction, HAE) and more sustainable nonconventional approaches (ultrasound and microwave-assisted extractions, UAE and MAE, respectively). A circumscribed central composite design was employed to optimize and describe the interactive effects among variables of the HAE, MAE (time and temperature) and UAE systems (time and ultrasound power), and their performances compared with the standard soxhlet extraction system. The optimum conditions were predicted as 150 min, 81.6 °C for HAE, 30 min, 400W for UAE, and 25 min, 134.6 °C, for the MAE system. The UAE system was identified as the most appropriate technique to obtain extracts with the highest amount of ergosterol, followed by MAE and HAE. Overall, these results demonstrate the potential of using the fruiting bodies of A. blazei as a suitable source to obtain ergosterol-rich extracts, which can be used as an ingredient for various biobased industrial applications.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2019); L. Barros thanks national funding by FCT, P.I., through the individual scientific employment program-contract for her contract; to the European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of Project MobilizadorNorte-01- 0247-FEDER-024479: ValorNatural®; to European Structural and Investment Funds (FEDER), through the Rural Development Program (PDR2020), within the scope of Project MicoCoating (PDR2020-101- 031472). The authors thank the GAIN (Xunta de Galicia) for financial support (P.P. 0000 421S 140.08) to M.A. Prieto by a post-doctoral (modality B) grant. R.C.G. Correa thanks CAPES Foundation, Ministry of Education, Brazil (CAPES fellow, process number 88881.120010/ 2016–01), for the financial support provided for her postdoctoral research in Polytechnic Institute of Bragança. Rosane Marina Peralta and Adelar Bracht are recipients of scientific productivity research grants from CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil), grants numbers 307944/2015-8 and 304090/ 2016-6, respectively. To project POCI-01-0145-FEDER-006984 – Associate Laboratory LSRE-LCM funded by FEDER through COMPETE2020-POCI and by FCT.