Nutrition regulation for the production of Monascus red and yellow pigment with submerged fermentation by Monascus purpureus

The potential economic values and applications of natural yellow and red pigments in the food industry, cosmetic, and textile cannot be underestimated. So the improvement of a bioprocess for better production of Monascus pigments (MPs) using nutrition regulation under submerged fermentation was carried out. An organic acid together with fermentation conditions such as pH has proved to be effective for pigment enhancement as well as cell growth. The combined effect of 10 g/L peptone and 1.5 g/L pyruvic acid yielded yellow (99.81 +/- 5.25 AU/ml) and red (97.22 +/- 6.12 AU/ml) pigments which are about 5 folds compared to control. Further investigation indicated that the pigment production in the acidic medium is better than the nearly neutral medium. The highest yellow (574.76 +/- 6.18 AU/ml) and red (570.98 +/- 7.66 AU/ml) pigment production were attained at the initial pH of 5.0. The study again showed that the effect of fermentation time on pigments, pH curve, and biomass production did not reach the decline phase given an indication of adequate nutrient in the broth for probable growth and pigment production. The present study gives the basic information on which the scaled-up production of valuable metabolites by filamentous fungi in submerged fermentation could be carried on.