Xylose (left graph), HMF (middle graph) and furfural (right graph) reduction activity measured in crude cell extracts from cells of strains USM21 and TMB3400. Cells were grown aerobically overnight in defined mineral medium. The assays were performed using NADH (top) or NADPH (bottom) as cofactor. The values are averages of two independent measurements. The bars represent the deviation from the average.