Carels M, Shepherd D
Can J Microbiol. 1977 Oct;23(10):1360-72. doi: 10.1139/m77-205.
Thirty-nine strains from the genus Monascus were cultivated aerobically to study the relation between nitrogen nutrition and sporulation and pigment production. The effects of yeast extract, nitrate, ammonium, and ammonium nitrate have been compared. During cultivation the pHs of the different media are not the same, resulting in the formation of different coloured pigments. When the source of nitrogen is yeast extract or nitrate the pH is around 6.5 and red pigments are formed, whereas with ammonium or ammonium nitrate the pH is around 2.5 and the pigments are orange. It is proposed that only the orange pigments, monascorubrin and rubropunctatin, are produced biosynthetically and that the other pigments are formed from these by chemical transformations depending on the cultural conditions. The presence of organic nitrogen is optimal for growth and unfavourable for pigment production. Reduced growth and best pigment formation occurs with the three other nitrogen sources. Nitrate stimulates conidiation and sexual reproduction, while ammonium is inhibitory. Pigment production is better when conidiation is reduced. A mechanism is proposed for the control of sporulation and pigment production.
对39株红曲霉菌株进行好氧培养，以研究氮营养与孢子形成及色素产生之间的关系。比较了酵母提取物、硝酸盐、铵盐和硝酸铵的影响。在培养过程中，不同培养基的pH值不同，导致形成不同颜色的色素。当氮源为酵母提取物或硝酸盐时，pH值约为6.5，形成红色色素；而当氮源为铵盐或硝酸铵时，pH值约为2.5，色素为橙色。有人提出，只有橙色色素红曲红素和红斑红曲素是通过生物合成产生的，而其他色素则是根据培养条件通过化学转化由这些色素形成的。有机氮的存在对生长最有利，但对色素产生不利。使用其他三种氮源时，生长减缓但色素形成最佳。硝酸盐刺激分生孢子形成和有性繁殖，而铵盐则具有抑制作用。分生孢子形成减少时色素产生更好。提出了一种控制孢子形成和色素产生的机制。
