The pretreated EFB hydrolysate was fermented using S. cerevisiae. Glucose consumption, bioethanol
production and cell concentration were monitored at 3, 6, 24, 48 and 72 h of S. cerevisiae cultivation. The yeast
cell adapted slowly to the medium (containing 26.7 g L-1 initial sugar concentration) in the beginning of
fermentation and its growth increased exponentially between 3 and 24 h (Fig. 4). The bioethanol was produced
started at early stage of fermentation and continuously increased and reached maximum level of 12.13 g L-1
within 24 h. This corresponded to bioethanol yield of 0.45 g ethanol/g glucose (Table 4). This value is
comparable to that of bioethanol produced from other renewable substrates by S. cerevisiae i.e. oil palm trunk
sap with 0.48 g/g [29]; oil palm trunk frond with 0.49 g/g [30]; sago pith residue with 0.48 g/g [31]; sugar beet
molasses with 0.41 g/g [32] and sweet sorghum stalk juice with 0.39 g/g [33]. After 24 h, the cell growth was
stagnant and entered the stationary phase and bioethanol production also declined slightly thereafter. This might
be due to the depletion of carbon source and hence the reverted consumption of the accumulated ethanol by the
organism. In this study, 89.1% of theoretical bioethanol yield was achieved with productivity of 0.51 g L-1 h-1
ferment the lignocellulosic-derived sugars from EFB to bioethanol.