Optimization And Production Of Monascus Rice With High Pigment And Low Citrinin Based On Solid-state Fermentation Process

As a natural pigment,Monascus pigment is often used as food colorant in southern China,Japan and Southeast Asia.However,there are still some problems in the production of Monascus pigment by solid-state fermentation,such as low productivity,high labor intensity and high citrinin content,which limit the application market of Monascus pigment.Based on this,in this project,the physical breeding system of normal temperature and atmospheric pressure plasma(ARTP)was used to mutate Monascus,and the culture conditions were optimized to obtain excellent strains with high pigment yield and low citrinin content1.Using ARTP physical breeding to improve the pigment production ability of Monascus,a mutant strain M6 was obtained.It was found that the highest Monascus pigment production was 11568 U/g,which was 387.15%higher than that of the original strain.After that,in order to reduce the content of citrinin,we got a good strain m6-5 with high pigment yield and low citrinin content through secondary ARTP screening.2.The effects of pH on Monascus pigment and citrinin were investigated.The results showed that the highest pigment yield was 2104 U/g and citrinin content was 0.5825 mg/g when pH was 4.When the initial pH value was lower than 2.4,the citrinin value was about 1.1775 mg/g,and the pigment yield decreased from 2104 U/g(pH=2.4)to 568 U/g(pH=4.0).3.Through the analysis of single factor test and box Box-Behnken response surface design,the strains which had significant effect on Monascus pigment production were screened.The results showed that the solid-state fermentation medium was MgSO4·7H2O 0.7g/l,nicotinic acid 0.03 g/L,soybean powder 1g/L,the predicted pigment yield was 3884.15 U/g,and the actual pigment content was 4102.20 U/g.