两步酸水解玉米芯条件及其酒精发酵的初步研究

Two Stages of Acid Hydrolysis for Corn Cob and Ethanol Fermentation

通过两步法———浓酸预处理与稀酸水解相结合 ,对玉米芯进行水解 ,初步确定较佳的玉米芯水解条件为 :72 %浓H2 SO4 常压 3 0℃预处理 2h ,再 0 1MPa 4%的稀H2 SO4 水解 1h。所得水解液中还原糖与五碳糖质量转化率分别为 81 %和 46%。经处理 ,浓缩 ,将其作为碳源 ,接种PichiastipitisCBS5 773进行酒精发酵 ,酒精产率是对照培养基的 77%。

A two-stage method, including pretreatment with high concentration sulphuric acid and hydrolysis with diluted sulphuric acid, was performed to hydrolate corn cob. The hydrolysis conditions were optimized as follows: pretreatment in 70%(w/w) H 2SO 4 at 30℃ for 1 hour and hydrolysis in 4% (w/w) H 2SO 4 at 120℃ for 1 hour. The conversion yield of reducing sugar and pentose in hydrolysate obtained were 81% (g/g) and 46% (g/g) respectively. The ethanol yield in hydrolysate medium was only 77% of that in simulated hydrolysate medium using the strain of Pichia stipitis CBS5773.