Optimization of culture conditions for bioethanol fermentation in oil palm fronds juice concentrates via Box-Behnken design

Response surface methodology via Box-Behnken design was used to evaluate the effect of culture conditions on bioethanol production by Kluveromyces marxianus in oil palm frond juice concentrate. In this study, the tested parameters were agitation speed, incubation temperature, inoculum size, pH, and initial glucose concentration; the responses were bioethanol yield and biomass. The optimum culture conditions obtained from the response surface analysis were agitation speed 117 rpm, incubation temperature 35 °C, inoculum size 4.0% (v/v), pH 6.59, and initial glucose concentration 44 g L−1, respectively. Under these conditions, the experimental data for bioethanol yield (0.47 g g−1) and biomass (5.61 g L−1) were close to the predicted values. © 2015, SAGE Publications Inc. All rights reserved.