Based on the above-described considerations, the present study evaluated the adaptation of a flocculent strain of S. cerevisiae (NRRL Y-265) to inhibitory compounds present in lignocellulosic hydrolysates. Experimental assays were performed under conditions of cell recycle batch fermentation (CRBF), in which the flocculating ability of the yeast was used for the cells separation and use in the subsequent batch cultures. This fermentation technique is used in this work as an alternative to other directed-evolution approaches, such as sequential batches or growth in solid media [8]. The yeast was cultivated in five different fermentation media containing sequentially increased concentration of inhibitory compounds, aiming to obtain a strain suitable for use on ethanol production from lignocellulosic materials by conventional fermentation methods.