It is important to emphasize that the adapted strain also showed an increased transformation rate for furfural, HMF and syringaldehyde, reaching basal levels of these inhibitors between 20 and 40 h earlier than the parent strain (Fig. 5). Acetic acid was not transformed over the course of the batch cultures. Similar profiles for these inhibitors and increased transformation rates for adapted strains have been reported [27] and [28]. Generally speaking, an adapted strain could have a higher growth rate in the presence of inhibitors. However, since furfural and HMF exert action over the lag phase of batch growth, an adapted strain might have attained, through directed evolution, a speedier biotransformation of inhibitors during lag phase (Fig. 5A), maintaining similar growth rate than the parent strain. An improved biotransformation rate is crucial for in situ detoxification of lignocellulosic hydrolysates, replacing expensive detoxification steps in bioethanol production. Thus, the adapted strain can be considered suitable for bioethanol production.