以白酒酒糟为原料发酵产丁二酸

以白酒酒糟为原料,经酶法糖化,由Actinobacillus succinogenes发酵生产丁二酸。纤维素酶或糖化酶分别水解白酒糟,在酶反应的最适温度和pH条件下,酒糟中的纤维素和淀粉的水解率分别为44.04%和92.26%,相应还原糖对酒糟的得率分别为110 mg/g和126 mg/g酒糟;但2种酶以分步或同步方式水解白酒糟时,酶水解反应受到产物抑制作用,总还原糖得率仅约为150 mg/g酒糟。采用分步糖化发酵工艺,400 g/L白酒糟经两种酶水解后,得到还原糖58.4 g/L,该水解液发酵产丁二酸28.8 g/L,丁二酸产率72 mg/g酒糟;而采用先用纤维素酶水解白酒糟,再用糖化酶和A.succinogenes同步糖化发酵的工艺,240 g/L白酒糟产丁二酸浓度为32 g/L,产率133 mg/g酒糟。以白酒酒糟为原料发酵生产丁二酸,利用了废弃物,无需外源添加氮源,无需对原料进行酸碱预处理,具有一定的应用前景。

Study on fermentative production of succinic acid from spirit-based distillers' grains

Spirit-based ditillers' grains(SDG) treated with enzyme hydrolysis was used as a stuff for fermentative production of succinic acid by Actinobacillus succinogenes.When the hydrolysis reaction was solely catalyzed by cellulase or amylase under its optimum temperature and pH,the corresponding hydrolysis rates of cellulose in SDG and starch in SDG were 44.04% and 92.26%,respectively.While hydrolysis using cellulase and amylase step by step(HSS),the later hydrolysis reaction could be restrained.Otherwise,the yield of reducing sugar in hydrolysis using cellulase and amylase simultaneously was about 150 mg/g SDG,the same as that of HSS.Using hydrolysis and fermentation separated process,58.4 g/L reducing sugar was obtained,which resulted in 28.8 g/L succinic acid with a yield of 72 mg/g SDG.However,using the procedure that firstly SDG was hydrolyzed with cellulase and then starch in SDG was simultaneously saccharified and fermented,32 g/L succinic acid was achieved with a yield of 133 mg/g SDG.This study provided a new economical stuff for fermentative production of succinic acid in the future.