摘要
为了提高红色红曲菌(Monascus ruber)M7发酵生产红曲素(monascin,MS)和红曲黄素(ankaflavin,AF)的产量,采用液态发酵法,探究不同发酵温度下其产生的醇溶性色素在组成和产量方面的变化规律.结果发现,当温度较低时(25、30℃),所产生的色素在470 nm有最大吸收,色调偏橙,红斑素(rubropunctatin,RP)和红曲红素(monascorubrin,MR)为优势组分;当温度较高时(35、40℃),所产生的色素在400 nm附近有最大吸收,色调偏黄,MS和AF成为优势组分.随着温度的升高,所有色素组分的产量均先升高后降低,其中,25、40℃不利于色素的产生,产量显著低于30、35℃;30℃时,RP和MR的产量达到最大值,分别为107、124 mg/L,而MS和AF的产量较低,分别为48、26 mg/L;35℃时,MS和AF的产量达到最大值,分别为100、47 mg/L,而RP和MR的产量相对30℃时显著降低,分别为57、50 mg/L.qPCR分析发现,温度对MS和AF液态发酵的影响与其对色素合成关键酶基因的转录调控密切相关,其中,对色素合成分支节点关键酶基因MrPigF和MrPigH的差异调节,可能对35℃时MS和AF产量的显著提高起到了较关键的作用.该结果可为提高MS和AF液态发酵产量提供参考.
To improve the production of monascin(MS)and ankaflavin(AF)by Monascus ruber M7,the changes in composition and yield of alcohol-soluble pigments produced at different fermentation temperatures were investigated using liquid state fermentation.It was found that pigments produced at lower temperatures(25、30℃)were orange in hue,with a maximum absorption around 470 nm,and rubropunctatin(RP)and monascorubrin(MR)were the dominant components;while pigments produced at higher temperatures(35、40℃)were yellow in hue,with a maximum absorption around 400 nm,and MS and AF became the dominant ones.As the temperature increased,the yields of each pigment compounds first increased and then decreased.The yields of all pigment compounds were significantly lower at 25、40℃than at 30、35℃,indicating that these temperatures were not conducive to the production of pigments.At 30℃,RP and MR had a maximum yield of 107、124 mg/L,respectively,while MS and AF had a lower yield,being 48、26 mg/L,respectively.At 35℃,MS and AF reached a maximum yield of 100、47 mg/L,while RP and MR decreased significantly when compared to 30℃,being 57、50 mg/L,respectively.qPCR analysis revealed that the influence of temperature on the liquid state fermentation of MS and AF was closely related to its transcriptional regulation on key genes responding to pigments biosynthesis.The differential regulation on MrPigF and MrPigH,the key enzyme genes of the pigments biosynthesis branch node,might playe a critical role in improving the yields of MS and AF at 35℃.These results would be helpful for the promotion of MS and AF during liquid state fermentation.
作者
徐勇
邱子娅
陈莎
张佳兰
高梦祥
李利
XU Yong;QIU Ziya;CHEN Suo;ZHANG Jialan;GAO Mengxiang;LI Li(College of Life Science,Yangtze University,Jingzhou 434025,China;Institute of Food Science and Technology,Yangtze University,Jingzhou 434025,China;College of Animal Science,Yangtze University,Jingzhou 434025,China)
出处
《河北大学学报（自然科学版）》
CAS
北大核心
2023年第4期408-419,共12页
Journal of Hebei University(Natural Science Edition)
基金
国家自然科学基金资助项目(31730068)。
关键词
红色红曲菌
红曲素
红曲黄素
液态发酵
温度
Monascus ruber
monascin
ankaflavin
liquid state fermentation
temperature
