溶氧对红曲菌发酵生物合成橙色素的影响

研究了溶氧对红曲菌在发酵罐中生物合成橙色素的影响。 分别采用不同通气量和搅拌转速以达到不同溶氧水平,考察不同溶氧水平下红曲菌w1夏在10L发酵罐中生产橙色素的情况,并将优化后条件放大至50L发酵罐中。结果表明,不同通气量水平下底物消耗、pH值和溶氧情况相似,但最终橙色素色价不同,基本上呈现出随通气量增加,色价呈现上升趋势；搅拌转速升高,菌体量和色价均随之升高,但涨幅不大；50L罐中菌体生长和橙色素合成结果验证了10L罐结果。在大规模生产时应尽可能采用高的通气量和适宜的搅拌转速,达到较高的溶氧水平,以利于菌体生长和橙色素合成。

Effects of Dissolved Oxygen on Biosynthesis of Orange Pigments in Monascus Fermentation

Effect of dissolved oxygen (DO) on the biosynthesis of orange pigments in Monascus fermentation was investigated in this study. The orange pigments production of the w1 Xia strain in a 10L bioreactor under different DO levels obtained using different ventilatory volumes and stirring speeds were studied. And the optimized conditions were applied in a 50L bioreactor. The results showed that the changing trend of substrate consumption, pH, and DO was similar under different ventilatory volume conditions, but the color value of orange pigments increased along with the ventilatory volume augment. The stirring speed did not have significantly effects on the biomass and color value of orange pigments. Meanwhile, the orange pigments production in a 50L bioreactor was similar to that in a bioreactor. In conclusion, the higher ventilatory volume and adapted stirring speed were beneficial to the biomass and orange pigments production.