2.4. Fermentation conditions
The fermentation was carried out at a temperature of 50 °C and a pH of 5.0. The fermentation media, same as growth medium except lower ammonium sulfate, 1.0 g l 1, prepared in glucose- rich hydrolysate and filtered through vacuum filtration using 0.2 mm Whatman GF/C filter paper, were fed into bioreactor at different dilution rates. The pre-grown cells of Kluyveromyces sp.