The ethanol production by S. cerevisiae Y904 in SFS in three
different media is given in Table 3. A significant increase in the final
ethanol content was observed for the SRW medium relatively to
that for other media; the ethanol content was 4.2 times that produced
in the SW medium. However, the reducing sugar consumption
indicated the existence of a nutrient limitation or
inhibitory metabolites in the medium. These results are in good
agreement with the results for similar tests with other substrates.
Wilkins et al. [13] noted that fruit byproduct hydrolysis by commercial
enzymes in SFS was not greatly affected by varying the
enzyme activity above 0.02 U/g. Stenberg et al. [14] observed an increase in ethanol yield with increasing cellulose loading up to a
certain saturation level.