不同碳源条件下金黄色蝶形担孢酵母发酵合成多糖的动力学及结构差异

Effects of Carbon Sources on Fermentation Kinetics and Structures of Exopolysaccharide From Papiliotrema aureus

为探究碳源对金黄色蝶形担孢酵母(Papiliotrema aurea)DF-12合成胞外多糖(EPS)的动力学及结构和功能的影响,本试验利用Logistic、Luedeking-Piret、Herbert-pirt模型拟合不同碳源条件下金黄色蝶形担孢酵母DF-12的动力学变化,并通过高效凝胶渗透色谱、红外光谱、扫描电子显微镜和气相色谱初步分析了不同碳源所得EPS的结构差异。结果表明,以葡萄糖为碳源时最大比生长速率为0.15 h^(-1),高于其他碳源,而以蔗糖为碳源时多糖比生产速率较高,达11.95 h^(-1)。同时不同EPS均具有较好的抗氧化活性。以葡萄糖和蔗糖为碳源所得不同EPS组分表面形貌存在差异,但其分子量、官能团和化学键无较大差异。此外,不同碳源(葡萄和蔗糖)所得EPS均由岩藻糖、鼠李糖、甘露糖、葡萄糖等单糖组成,但其摩尔比存在一定的差异。本研究结果为酵母菌EPS的进一步开发和利用提供了理论依据。

To investigate the effects of carbon sources on the synthesis kinetics,structure and function changes of exopolysaccharides(EPSs)from Papiliotrema aurea DF-12.Logistic,Luedeking-Piret and Herbert-pirt models were used to fit the growth and EPSs production with different carbon source,and the structural differences of these EPSs were studied by high performance liquid chromatography,infrared spectra,scanning electron microscopy and gas chromatography.The results showed that when glucose was used as carbon source,the maximum specific growth rate reached to 0.15 h^(-1),which was higher than that of other carbon sources.However,the maximum specific product formation rate was get when sucrose was used as carbon source,which was reached to 11.95 h^(-1).All of the EPSs exhibited strong antioxidant activities.There was no significant difference in molecular weight,functional groups and chemical bonds with different carbon source,except for surface morphology.EPSs obtained from all kinds of carbon sources(glucose and sucrose)were composed of fucose,rhamnose,mannose and glucose,while their molar ratio was different.The results of this study provide a theoretical basis for further development and utilization of yeast EPSs.