微生物发酵对玉米秸秆多糖产量及基本结构特征影响

为了进一步探索玉米秸秆的资源化利用途径,本研究以秸秆为唯一碳源进行发酵,并监测了发酵过程中多糖的含量变化。实验组与对照组经Sevage法除蛋白后通过醇沉得到多糖产品FFSP和FFSP0,利用气相色谱(GC)、傅里叶变化红外光谱(FT-IR)和扫描电子显微镜(SEM)对两种多糖产品的基本结构和表面形貌进行了分析对比。结果表明,实验组中发酵液多糖含量比对照组增加了677.54 mg/L;虽然FFSP和FFSP0均主要由鼠李糖、阿拉伯糖、木糖、葡萄糖、甘露糖和半乳糖组成,但其摩尔比由FFSP0的1:4.6:6.5:1.4:2.9:2.5变为1:13.4:16.8:3:2.7:8.4,微生物的存在增加了多糖的含量,并改变了多糖产品的单糖组成;SEM显示FFSP0为粒径小的粗糙的球体,而FFSP为粒径大的较光滑球体。上述实验结果表明,微生物的加入对秸秆多糖的产量与基本结构产生了一定的影响,这为秸秆的综合利用提供了一个新的途径和方向,也为以后的进一步研究提供了实验依据。

Effect of microbial fermentation on yield and structural characteristics of polysaccharide from corn stalk

In order to make the further exploration in resource utilization of corn stalk,the corn stalk was used as the sole carbon source for fermentation,and the content of polysaccharides in the fermentation process was measured. The polysaccharide products FFSP(test group)and FFSP0(control group)were obtained by alcoholic precipitation after the disposal via the Sevage method,while the basic structure and surface morphology of the two polysaccharide products were analyzed by gas chromatography(GC),Fourier transform infrared spectroscopy(FT-IR)and scanning electron microscopy(SEM). The results showed that the content of polysaccharide had increased by 677.54 mg/L than FFSP0 after fermentation. In addition,GC revealed that FFSP and FFSP0 were mainly composed of rhamnose,arabinose,xylose,glucose,mannose and galactose,respectively,but its molar ratios changed from1:4.6:6.5:1.4:2.9:2.5 to 1:13.4:16.8:3:2.7:8.4.The presence of microorganisms increased the polysaccharide content and changed the polysaccharide composition of the polysaccharide. SEM showed that FFSP0 was a coarse sphere with a small particle size,while FFSP was a relatively smooth sphere with a larger particle size. There were significant differences in the polysaccharides that obtained in both ways. The results showed that the addition of microorganisms had a certain effect on the yield and basic structure of straw polysaccharides,which provided a new way and direction for the comprehensive utilization of straw,and provided the experimental basis for further research.