Fermentation of samples after 48 h of enzymatic hydrolysis was carried out in 2 mL reaction tubes for 24 h at 28 C. These samples were supplemented with 4 g/L of Prodex and 1 g/L of (NH4)2SO4 and inoculated with S. cerevisiae CAT-1 to reach a total of 1 108 viable cells per mL.
Samples were taken at different intervals to determine the kinetics of sugar consumption and ethanol production. Sugar and ethanol concentrations were analysed by HPLC using an Aminex HPX-87H column as described above. The ethanol yield was expressed as Y(P/S) and calculated as follows (Eq. (1)),