초록
For consolidated bioprocessing (CBP), components of Jerusalem artichoke (Helianthus tuberosus L.) tubers and stalks as a potential bioenergy crop were analyzed as carbon and nutrient sources, respectively. The effectiveness of chemical pretreatment with dilute acid or alkali was evaluated to develop a CBP method. Cellulose content, delignification, and enzymatic hydrolysis efficiency of the pretreated stalks were increased more effectively by NaOH treatment than dilute H<SUB>2</SUB>SO<SUB>4</SUB> treatment. However, weight loss was greater during alkali pretreatment. Additionally, large volumes of water were required to wash the alkali-treated biomass. Therefore, CBP using the dilute acid-pretreated stalk and the ground tuber of Kluyveromyces marxianus were investigated. Fermentation of both pretreated stalks and tubers by K. marxianus with no nutrient supplementation proceeded acceptably. At 10% (w/v) stalk and 8% (w/v) tuber loading, K. marxianus produced 45.3 g/L ethanol after 30 h. The ethanol yield was 0.252 g ethanol per g dry biomass, or 0.32 g ethanol per g fermentable sugars, with a fermentable sugar conversion rate of 60%. These results suggest a cost-effective CBP strategy for bioethanol production from the whole Jerusalem artichoke plant.