(1.北京工商大学 北京食品营养与人类健康高精尖创新中心, 北京 100048;2.北京市食品添加剂工程技术研究中心, 北京 100048)
(1.Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, Beijing 100048, China;2.Beijing Engineering and Technology Research Center of Food Additive, Beijing 100048, China)
以北京市食品添加剂工程技术研究中心实验室保藏的 Monacolin K产量稳定的紫色红曲菌M1为出发菌株,利用紫外-可见分光光度法、超高效液相色谱法以及实时荧光定量PCR法,通过测定红曲色素含量、Monacolin K含量等,探究烟酰胺添加对红曲菌合成次级代谢产物的影响。结果表明:实验组红、橙、黄3种色素产量与对照组菌株相比均有所降低；Monacolin K产量较对照组提高了31.34%,达到124.23mg/L。电镜观察发现,实验组菌株的孢子头和菌丝体褶皱程度明显多于对照组菌株。实时荧光定量PCR发现,实验组与Monacolin K产量相关的mokA、mokB、mokC、mokD、mokE、mokF、mokG和mokH基因的表达量均呈上调趋势,而mokI基因呈下调趋势。实验以烟酰胺为添加物进行探究,以期为红曲菌培养基优化,高产Monacolin K产品筛选提供参考。
Monascus purpureus M1 with stable yield of Monacolin K preserved in the Beijing Engineering and Technology Research Center of Food Additive, was used as the starting strain, the effects of nicotinamide addition on the secondary metabolites of Monascus were investigated by ultraviolet visible spectrophotometry, ultra-high performance liquid chromatography and real-time fluorescent quantitative PCR. The results showed that the yield of red, orange and yellow pigments in the experimental group was lower than those in the control group, and the yield of Monacolin K increased 31.34% to 124.23mg/L. Electron microscope observation showed that the degree of folding of spore head and mycelium in the experimental group was significantly higher than that in the control group. Real-time fluoresent quantitative PCR showed that the expression levels of mokA, mokB, mokC, mokD, mokE, mokF, mokG and mokH genes related to the yield of Monacolin K were up-regulated, while the expression level of mokI genes was down regulated. Nicotinamide was used as additive in the experiment, and the results were expected to provide reference for the optimization of Monascus culture medium and the screening of high-yield Monacolin K products.