Fermentation of enzymatic hydrolysate of sunflower hulls for ethanol production and its scale-up

Pretreated sunflower hulls hydrolyzed with Trichoderma reesei Rut C 30 cellulase showed 59.8% saccharification. Enzymatic hydrolysate concentrated to 40 g/l reducing sugars was fermented with Saccharomyces cerevisiae var. ellipsoideus under optimum conditions of time (24 h), pH (5.0), temperature (30°C) and inoculum size, and it showed a maximum ethanol yield of 0.454 g/g. Ethanol production scaled up in 1 and 15 l fermentors under optimum conditions revealed maximum ethanol yields of 0.449 and 0.446 g/g, respectively.