Impacts of carbon and nitrogen sources on color value and tone value of yellow Monascus pigments

In this study,the fermentation conditions for the yellow pigments produced by submerged fermentation of Monascus sp.sjs-6 were investigated.It was found that the carbon sources varieties had large impact on the output of Monascus yellow pigments.However,not only the yield but also the kinds of pigment were affected by different nitrogen sources of culture medium.Organic nitrogen source could promote the production of orange,red pigment,but inorganic nitrogen source was good at the production of yellow pigment.Incubating at 30 ℃ for 6 days,a high yield( 378 U / m L) of Monascus yellow pigments( MYP) was obtained in the optimum fermentation medium,in which,6%( w / v) corn starch,0.4%( w / v)( NH4)2SO4was used as the carbon,nitrogen source,respectively with initial p H of 5.0.Moreover,the MYP had single absorption peak at 420 nm which was different from the studies by other researchers.The yield of MYP presented in this research was more than 3 times over the other reports in our country.As it was a wild strain without mutant,the strain was relatively stable than the mutant strains reported by other researchers.So,this study would lay a foundation for the subsequent large scale production of MYP.