【目的】动物双歧杆菌RH产生的胞外多糖(exopolysaccharides, EPS)经阴离子交换柱层析可获得EPSa和EPSb两个组分。得到可提高EPS的总产量, 尤其是EPSb产量的最佳培养基和培养条件。【方法】对培养基类型、氮源、碳源、碳源浓度、培养基初始pH值、培养温度和时间对双歧杆菌EPSa和EPSb产量的影响进行分析。【结果】在初始pH值调整为7.0的含5%蔗糖的PTYG培养基上, 在35 °C温度下厌氧培养60 h时动物双歧杆菌RH的EPSa和EPSb产量分别为0.982±0.003 g/L和0.312±0.001 g/L。【结论】在上述条件下EPS总产量高且可获得较多的EPSb。
[Objective] Exopolysaccharides produced by Bifidobacterium animalis RH were fractionated into two peaks by anion exchange chromatography, named as EPSa and EPSb. The aim of the study was to obtain the optimal conditions for high yield of total EPS, especially EPSb. [Methods] In this paper, the effects of medium types, nitrogen source, carbon source, carbon concentration, initial medium pH, cultivation temperature and cultivation time on the yield and proportion of EPSa and EPSb were evaluated. [Results] The highest yield and favorable proportion were obtained in PTYG broth medium (pH 7.0) containing 5% sucrose when B. animalis RH was anaerobically cultivated at 35 ℃for 60 h. [Conclusion] Under these conditions, the yield of EPSa and EPSb were 0.982±0.003 g/L and 0.312±0.001 g/L, respectively.