Monascus pigment

Monascus pigments have been used in Asian countries for centuries as food colorants and spices and in traditional medicine. These pigments are produced by the fungi of Monascus genus cultivated on carbohydrate-rich substrates such as rice, wheat, com, potatoes, and soybeans. Three species of Monascus identified are pilosus. 

FIGURE 5.2.4 Chemical structures of some Monascus pigments. 

The main concern regarding the utilization of Monascus pigments relates to the production of the citrinin mycotoxin in Monascus cultures. Several methods for controlling the mycotoxin production were proposed, including selection of non-toxinogenic strains, control of citrinin biosynthesis, and modifications of culture conditions. Despite their wide and traditional food applications in Asian countries, Monascus pigments have not been approved for use in the United States or European Union. 

Hajjaj, H. et ah. Production and identification of N-glucosylrubropunctamine and N-glucosyhnonascorubramine from Monascus ruber and occurrence of electron donor-acceptor complexes in these pigments, Appl Environ. Microbiol, 63, 2671, 1997. Jung, H. et ah. Color characteristics of Monascus pigments derived by fermentation with various amino acids, J. Agric. Food Chem., 51, 1302, 2003. 

Monascus is often encountered in Oriental foods, especially in southern China, Japan, and southeast Asia. Currently, more than 50 patents have been issued in Japan, the United States, France, and Germany concerning the use of Monascus pigments... 

MEKC has been applied for the study of the effect of Monascus pigments on the decomposition of the mutagenic 3-hydroxyamino-l-methyl-5H-pyrido[4,3-b]indole (Trp-P-2(NHOH)). The chemical structures of yellow and red pigments are shown in Fig. 2.165. 

T. Watanabe, T.K. Mazumder, A. Yamamoto, S. Nagai, S.Arimoto-Kobayashi, H. Hayatsu and S. Terabe, A simple and rapid method for analyzing the Monascus pigment-mediated degradation of mutagenic 3-hydroxyamino-l-methyl-5H-pyrido[4,3-b]indole by in-capillary micellar electrokinetic chromatography. Mutat. Res. 444 (1999) 75-83. 

FIGURE 2 Chemical structures of selected second metabolites from Monascus. (A) Monascus pigments, (B) monacolins, (C) citrinin. 

There are six well-known Monascus pigments (azaphilones) that are produced and are divided into three pairs. Rubropunctatin (C21H22O5) and monascorubrin are orange pigments with different aliphatic... 

Only a few species of Monascus can produce monacolin K (Table 1). Since Monascus pigments and monacolin K are made by the same or similar polyketide-forming enzymes (Turner and Aldridge, 1983), the ability of various species of Monascus to produce monacolin K may be predicted based on its mycelia color. 

Jung, H., Kim, C., and Shin, C. S. 2005. Enhanced photostability of monascus pigments derived with various amino acids via fermentation. J. Agric. Food Chem. 53(18), 7108-7114. 

Yoshimura, M., Yamanada, S., Mitsugi, K., and Hirose, Y. 1975. Production of Monascus pigment in a submerged culture. Agric. Biol. Chem. 39,1789-1795. 

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