The aim of this study was to optimize of independent variables as temperature, time and reaction ratio to output parameter of
simultaneous enzyme saccharification and fermentation by Saccharomyces cerevisiae of pretreated wheat straw as model substrate via
RSM (response surface methodology) approach. As dependent variable, it was chosen ethanol yields characterizing effectivity of
process. The optimal conditions were approximately temperature 100 °C, time 1 hour and reaction ratio 26 mL to 1 g of treated wheat
straw with ethanol yields 141.9 mg.g-1. After calculating the optimal values, the validation analyze was carried out and it was found out
that the predicted and experimentally verified dependent variable was in agreement with the optimal parameters (~ 95 %). Proposed
model was tested for three lignocellulosic materials (winter wheat straw, alfalfa hay and maize straw) as wheat straw used as model
substrate and it was confirmed the possibility of its use for other agricultural residues with similar content of lignocellulose.