提出了一种乙酸催化耦合酶水解蔗髓一体化生产低聚木糖(XOS)和低聚葡萄糖(COS)的方法。首先对乙酸催化蔗髓中半纤维素水解的工艺条件进行了响应面法优化，结果表明:在172 ℃、42 min条件下，使用质量分数为2。02％的乙酸催化蔗髓水解，可以获得最高46。9％的XOS产率。在考察底物质量分数、酶种类和木质素对COS产率的影响后，将乙酸水解蔗髓后的固体产物采用对甲苯磺酸法脱除木质素，之后在10％的底物质量分数下使用内切葡聚糖酶进行酶解，COS产率达47。2％，是未脱除木质素且使用纤维素酶水解时的2。3倍。结构表征表明:乙酸催化水解和对甲苯磺酸处理有效去除了原料中的半纤维素和木质素，打破了三大素间的纠缠结构，降低了纤维素结晶度，增加了原料表面孔隙率，从而提高了酶对纤维素的可及性。最终，1 kg蔗髓一体化水解可制得36。3 g XOS和230 g COS。
Integrated Production of Oligosaccharides From Bagasse Pith
A method for integrated production of xylo-oligosaccharide(XOS)and cello-oligosaccharides(COS)from bagasse pith by acetic acid catalyzed coupling with enzymoatic hydrolysis of bagasse pith was proposed.Firstly,the process conditions for acetic acid catalyzed hydrolysis of hemicellulose in bagasse pith were optimized by response surface methodology.The results showed that under the condition of 172℃,42 min,by using 2.02％acetic acid,to catalyze the hydrolysis of bagasse pith,a maximum xylo-oligosaccharide yield of 46.9％could be obtained.After investigating the effects of substrate concentration,enzyme types,and lignin on the yield of oligosaccharides,the solid product after acetic acid hydrolysis was delignified by p-toluenesulfonic acid method and then enzymolysised by endoglucanase at a 10％substrate concentration.The yield of cello-oligosaccharides reached 47.2％,which was 2.3 times that of cellulase hydrolysis without lignin removal.The structure characterization showed that the acetic acid catalyzed hydrolysis and the treatment of p-toluenesulfonic acid effectively removed the hemicellulose and lignin in bagasse pith,broke the entangled structure among the three components,decreased the crystallinity of cellulose,increased the surface porosity of the raw material,thereby improving the accessibility of enzyme to cellulose.Finally,36 g XOS and 230 g COS were obtained from integrated hydrolysis of 1 kg bagasse pith.
万方数据
维普
