Tween-60对出芽短梗霉合成多糖代谢组学的分析

Metabolomics analysis of Tween-60 on pullulan by Aureobsidium pullulans

利用代谢组学技术,研究了Tween-60对出芽短梗霉合成普鲁兰多糖的影响。在初始发酵培养基中添加4 g/L的Tween-60,并采用GC-MS(Gas chromatography-mass spectrometry)对实验组和空白组40 h的胞内代谢物进行分析。结果表明:普鲁兰多糖产量由78.35 g/L提高至92.5 g/L;同时确定出包括L-阿拉伯糖醇、D-核酮糖等6种代谢物表达量上调,α-D-葡萄糖、D-半乳糖等6种代谢物表达量下调。进一步分析表明,添加Tween-60可以增强胞内TCA循环以及戊糖、葡萄糖醛酸循环,为出芽短梗霉代谢提供大量能量以及胞内保护性物质。同时,发现添加Tween-60加快胞内半乳糖代谢,进而促进了普鲁兰多糖发酵前体UDPG的合成,因而多糖产量显著增高。

In this paper, the influence of Tween-60 was studied on pullulan production by Aureobsidium pullulans. Tween-60 was added to the initial fermentation medium. Intracellular metabolites of blank and experimental group based on GC-MS were analyzed. The results showed that the production of pullulan increased from 78.35 g/L to 92.5 g/L. The expression levels of six metabolites were up-regulated, including L-Arabitol, D-Ribulose; other six metabolites were down-regulated, including alpha-D-Glucose, D-Galactose. Further analysis showed that Tween-60 could enhance the intracellular TCA cycle and the pentose and glucuronic acid cycle, which provided a lot of energy and intracellular protective substances for the metabolism of Aureobsidium pullulans. At the same time, it was found that Tween-60 could accelerate the metabolism of intracellular galactose, and promote the synthesis of UDPG. And thus the yield of pullulan was significantly increased.