Enzyme recycling in a simultaneous and separate saccharification and fermentation of corn stover: A comparison between the effect of polymeric micelles of surfactants and polypeptides

► Polymeric micelles (PMs) of PEG-casein improved cellulase activity in SHF and SSF. ► PEG-casein, PEG-Tween efficacy in enzyme recycling was compared with casein and Tween. ► The ethanol yield was increased by 85.7%(PEG-casein), 57.1%(PEG-Tween) in one cycle. ► PEG-casein and PEG-Tween improved ethanol yield to 108% after two enzyme recyclings. ► Efficacy of PMs varied based on casein type (obtained from ultrafiltration, acid).