Optimization Of Induction Conditions For Producing Red Pigment By Monascus

As a natural and high-quality edible pigment, monascus colorant has been widely applied in food and medicine industries. This paper investigated impacts of carbon sources, carbon sources, pH values in culture medium on production of monascus colorant by single factor experiment, and determined the composition of the liquid fermentation culture medium. Moreover, we studied growth, and intracellular and extracellular pigment amounts of monascus induced by saccharomycetes and their homogenates.Experimental results are shown as follows:The optimum carbon source and nitrogen source of monascus liquid fermentation culture medium were starch and milk powder, respectively, and the optimum pH value was 5.4. The most appropriate condition of culture was 3% of starch,0.2% of milk powder,0.1% of K2HPO4,0.001% of FeSO4,0.05% of KCl and 0.05% of MgSO4·7H2O. Additionally, lactic acid was used to adjust pH value to 5.4,50 mL liquid was added to a 100 mL triangle bottle, and fermental cultivation was carried out for 6 days at 32 ? on a rotary shaker at 170 rmp.Mixed cultivation of monascus and saccharomycetes could increase output of monascus colorant obviously. The output of culture with 12 mL monascus and saccharomycetes (105/mL) reached its peak after 5-day mixed cultivation. Compared with the cultivation using monascus alone, contents of extracellular haematochrome and intracellular haematochrome were increased by 41.75% and 21.24%, respectively, and dry weight of thallus increased by 100%. Cell homogenate could also increase the amount of the pigment produced by monascus; after 5-day mixed cultivation, it reached its maximum when 4mL saccharomyces were added; compared to the cultivation using monascus alone, the contents of extracellular and intracellular haematochrome were increased by 55.99% and 20.87%, respectively, and dry weight of thallus grew by 19.35%.