BIOSUGARS PRODUCTION FOR ETHANOL FERMENTATION FROM RICE STRAW

บทคัดย่อ

                 Rice straw is available in large quantities in Thailand and is attractive as a lignocellulosic material resource for biosugars production. Dilute acid was used to pretreated the rice straw before enzymatic hydrolysis. The maximum overall sugar yield (62.59 g/100 g dry rice straw) was achieved at 4% (v/v) H₂SO₄ for 30 min, representing 80% of the total sugar in the rice straw. Under this condition, the concentrations of acetic acid, furfural and HMF in the hydrolysate were 1.72, 0.16 and 0.06 g/l respectively. For ethanol production, simultaneous saccharification and fermentation (SSF) and separate hydrolysis and fermentation (SHF) were employed using Pichia stipitis JCM 10742 with acid pretreatment. Results indicated that both ethanol concentration and productivity using SSF were higher than the SHF process. Ethanol concentration and productivity for SSF attained 9.21 g/l and 0.30 g/l h in 30 h fermentation respectively, while the SHF process achieved 6.10 g/l and 0.16 g/l h in 36 h. Results indicated that dilute acid pretreatment can be successfully applied to rice straw for biosugars production.