Anka and anka pigment production.

This study was conducted to determine the time-dependent changes of solid-state fermentation of rice with Monascus purpureus to produce anka and anka pigments. Growth of the fungus occurred prior to the synthesis of anka pigments. A steady increase in the yield of pigments occurred between the 5th and 15th days. After 15 days, growth of the fungus on rice substrate ceased and the yield of yellow anka pigments remained constant; however, orange anka pigments were reduced with a decreasing rate of 3.6 mg/g anka/day.