补料工艺对两株法夫酵母菌株产虾青素的影响

Influence of different fed-batch fermentation modes on astaxanthin production with two Phaffia rhodozyma strains

摘要:

【目的】考察不同补料工艺对法夫酵母菌株生长和虾青素合成的影响。【方法】对法夫酵母JMU-VDL668和JMU-MVP14菌株在7 L罐中进行分批及分批补料培养; 同时, 测定发酵过程中生物量、虾青素和葡萄糖含量的变化。【结果】采用恒DO补料, 法夫酵母JMU-VDL668菌株获得的生物量最大(64.6 g/L), 是分批培养的2.2倍; 采用恒pH补料发酵, 虾青素的产量最高(20.6 mg/L), 是分批培养的1.5倍。与JMU-VDL668菌株不同, 虾青素高产菌株JMU-MVP14菌株采用恒pH补料, 获得生物量最大(48.5 g/L), 但虾青素产量大大降低(仅17.5 mg/L); 采用脉冲补料, 虾青素产量最高, 达到414.1 mg/L, 与分批发酵相比提高了200.2%; 采用恒DO补料, 生物量(38.5 g/L)和虾青素产量(403.2?mg/L)增加显著, 与分批发酵相比分别提高了133.1%和192.3%。【结论】不同补料工艺对法夫酵母菌株生产虾青素影响很大。其中, 采用恒pH补料工艺, 法夫酵母JMU-VDL668菌株可以获得最高的虾青素产量, 而采用脉冲补料工艺, 最适于法夫酵母JMU-MVP14菌株发酵生产虾青素。

Abstract:

[Objective] Several fed-batch fermentation modes were studied to investigate the effect on cell growth and astaxanthin synthesis of Phaffia rhodozyma. [Methods] Biomass, astaxanthin concentration and residual sugar concentration were detected when two Phaffia rhodozyma strains (JMU-VDL668 and JMU-MVP14) were fermented in 7 L bioreactor by batch and fed-batch culture. [Results] The highest biomass (64.6 g/L) of Phaffia rhodozyma JMU-VDL668, which was more than 2.2 times of batch culture, was obtained from DO-stat feeding culture; and pH-stat feeding culture brought the highest astaxanthin concentration (20.6 mg/L), which was 1.5 times of batch culture. Differently with the results of Phaffia rhodozyma JMU-VDL668, the highest astaxanthin concentration (414.1 mg/L) of Phaffia rhodozyma JMU-MVP14 was obtained by Pulse-fed culture, which increased by 200.2% compared with batch fermentation. Actually, biomass (38.5 g/L) and astaxanthin concentration (403.2 mg/L) were also improved significantly when DO-stat feeding culture was used, increased by 133.1% and 192.3% compared with batch fermentation respectively. [Conclusion] The production of astaxanthin had a significant effect due to different fed-batch fermentation modes. What’s more, the highest astaxanthin concentration of Phaffia rhodozyma JMU-VDL668 was obtained by pH-stat feeding culture while Pulse-fed culture was optimal for Phaffia rhodozyma JMU-MVP14 to product astaxanthin.