Values of QE related to original size particles were lower than those RO 4929097 obtained with small size particles, and the ethanol production rate dropped quickly over bioprocess time except for experiments carried out with E&LHW solids where QE reached values of 0.11 kg m−3 h−1 (for SSP) and 0.14 kg m−3 h−1 (for OSP) at 72 h ( Table 3). The highest volumetric ethanol productivities (2.02 kg m−3 h−1 and 1.84 kg m−3 h−1) were obtained at 6 h in cultures that used E&DSA pretreated solids. Nikoli? et al.  achieved QE close to 2.7 kg m−3 h−1 when S. cerevisiae var. ellipsoideus grew on ultrasonic pretreated corn meal. Our QE data for DSA experiments were similar to those reported by Cuevas et al. , who obtained a QE value of 0.27 kg m−3 h−1 after 12 h of fermentation when olive pruning debris pretreated with dilute sulphuric acid (0.002 M) at 185 °C for 5 min was subjected to SSF process with the yeast S. cerevisiae IR2-9a.