不同温度对红曲霉液态发酵合成红曲黄色素及桔霉素的影响

Effect of Different Temperatures on the Synthesis of Monascus Yellow Pigment and Citrinin by Monascus Liquid Fermentation

研究红曲霉GN液态发酵过程中不同温度对红曲黄色素和桔霉素合成代谢的影响。在相同的培养基下,红曲霉GN分别在不同温度(20,22.5,25,27.5,30℃)液态发酵培养7 d,检测发酵终止时红曲黄色素和桔霉素含量,分析其变化和原因。结果表明:不同温度影响发酵终止pH值,发酵温度越低,发酵终止pH值越低,在20℃和30℃发酵过程中的pH值均不利于色素和桔霉素的合成;在22.5℃时红曲黄色素含量达到最大值,但是桔霉素的含量也达到最大值。故25℃时的发酵终止pH为3.38,红曲黄色素的含量较高,桔霉素含量相对较低,相较于其他温度,25℃更适合红曲黄色素的发酵生产。

The effects of different temperatures on the synthesis and metabolism of Monascus yellow pigment and citrinin in the liquid fermentation of Monascus GN are investigated.In the same medium,Monascus GN is fermented at different temperatures(20,22.5,25,27.5,30℃)for 7 days respectively.The content of Monascus yellow pigment and citrinin is detected at the end of fermentation,and their changes and reasons are analyzed.The results show that different temperatures affect the pH value at the end of fermentation.The lower the fermentation temperature,the lower the pH value at the end of fermentation.The pH values during 20℃and 30℃fermentation process are not good for the synthesis of pigment and citrinin.At 22.5℃,the content of Monascus yellow pigment reaches the maximum,but the content of citrinin also reaches the maximum.At 25℃,the pH value at the end of fermentation is 3.38,the content of Monascus yellow pigment is higher,and the content of citronin is relatively lower.Compared with the other temperatures,25℃is more suitable for the fermentation of Monascus yellow pigment.