碱预处理秸秆同步糖化发酵生产丁二酸

Succinic Acid Production from Alkali Pretreated Stalk by Simultaneous Saccharification and Fermentation

研究了碱预处理秸秆及用琥珀酸放线杆菌Actinobacillus sucinogenes同步糖化发酵秸秆生产丁二酸。结果表明:用1.0%NaOH溶液于120℃分别预处理玉米、小麦和水稻3种秸秆2 h,其木质素的脱除率、纤维素与半纤维素的总保留率均在85%以上。以3种碱预处理后的秸秆为原料,在补加纤维素酶与纤维二糖酶的条件下,A.sucinogenes F3-21摇瓶厌氧发酵72 h,产丁二酸浓度分别为30.74 g/L、24.98 g/L和26.57 g/L;在7 L罐中厌氧发酵72 h,丁二酸浓度分别达到40.21 g/L,30.06 g/L和39.07 g/L,每克预处理秸秆产丁二酸分别为0.50g、0.38 g和0.49 g。并用钙盐法对玉米秸秆同步糖化发酵液进行提取,得到纯度为99.98%的丁二酸结晶。说明了玉米、小麦和水稻3种秸杆为原料进行同步糖化发酵生产丁二酸的可行性。

In this paper, alkali pretreatment of corn, wheat and rice three stalks, as well as succinc acid （SA） production by simultaneous saccharification and fermentation （SSF） from the pretreated stalks were investigated. Re- sults showed that when corn, wheat and rice stalks were pretreated with 1.0% NaOH concentration at 120℃ for 2 h, the rates of both lignin removal and cellulose-hemicellulose remains were more than 85%. In the conditions of cellulose and eellobiase added, 30.74 g/L, 24.98 g/L and 26.57 g/L SA were achieved using the corn, wheat and rice pretreated stalks as stuff respectively, when SSF were performed 72 h by Actinobacillus sucinogenes F3 -21 in 150 mL flask. While in a 7 L stirred bioreaetor, SA concentration were obtained 40.21 g/L, 30.06 g/L and 39.07 g/L in 72 h, and its yields of each per gram of pretreated stalks reached 0.50 g, 0.38 g and 0.49 g correspondingly. Moreover the extraction of SA by precipitation from the broth of corn stalk SSF was attempted. SA crystal with a purity of 99. 89% was obtained. The results suggest the feasibility of SA production by SSF from corn, wheat and rice stalks.