Study on solid-state fermentation conditions for Monascus pigments production by Monascus purpureus JR.

In this paper,the solid-state fermentation conditions were optimized for improving monascus pigments production by Monascus purpureus JR.Firstly,the effects of different process parameters such as initial moisture contents,medium volume and inoculum volume on monascus pigment content were investigated,and the results revealed that a moisture content of 40%,a medium volume of 25 g/250 mL shake-flask and an inoculum volume of 5% were the optimal fermentation conditions for Monascus purpureus JR;Finally,the concentrations of nitrogen source(peptone) and inorganic salts(MgSO4,ZnSO4 and MnSO4)added to rice medium were optimized with the method of orthogonal experiment design.As a result,the optimal solid-state fermentation medium for Monascus purpureus JR was as follows(g/250 mL shake-flask): rice 25,peptone 0.5,MgSO4 0.0125,MnSO4 0.0025.The final monascus pigment content under this fermentation medium reached 895 U/mL,which was 76.18% higher than that obtained with the original medium recipe(rice 25 g/250 mL shake-flask).