Studies On Screening Of Monascus Pigment And Functional Monascus-producing Monascus Species And Optimization Of Production Conditions

The application of Monascus has been more than one thousand years in China. It hasbeen applied in the traditional food processing industry as a magical microorganism. In recentyears, many domestic and foreign experts have found two kinds of important matter in theMonascus metabolites: Monascus pigment and Monacolin K. The application of Moanscuspigment as nature coloring agent in the wine, food, pharmacy and cosmetic fields has been along history. At1979, in the Monascus ruber metabolites, Endo found Monacolin K, asubstract which may lowering cholesterol and maintain a healthy blood lipid level. The greatfounding has aroused the boom of the research about lipid-lowering Monascus in the world,and the great medicinal value of the Monascus has gradually attracted the people’s attention.However, although there has a long history of using Monascus in China, but the production ofMonascus pigment and Monacolin K in the industrial fermentation yield is pitiful, and theproduction cost is high and the economic benefit is far behind the developed countries.Therefore, improving the production of the Monascus pigment and Monacolin K has a veryimportant practical significance, especially instructive to their industrial production. In thisstudy, the high yield strains for producing Monascus pigment and Monacolin K were screened,and the fermentation conditions were optimized systematically. As a result, the productionshave been greatly improved. The main results are as follows:(1) In this study, a total of11strains of Monascus were isolated and namedMY-01-MY-11. They were divided into four kinds: MY-01, MY-04-MY-08were Monascuspurpureus; MY-02and MY-09were Monascus pilosus; MY-03and MY-11were Monascusruber; MY-10was Monascus sanguineus. Through the single factor experiment, an originalstrain MY-03, which had a stable characteristic and high production of Monascus pigmentwas selected in liquid state fermentation. Similarly, MY-01was selected as a original strain for producing Moancloin K in solid state fermentation.(2) Monascus rubber MY-03was adopted to produce Monascus pigment in the liquidstate fermentation, and the fermentation conditions were optimized by the single factorexperiment, Plackett-Burman design and RSM. The results showed that the optimum mediumwas composed of glucose50g/L, peptone58.07g/L, MgSO42g/L, NaNO32g/L, MnSO40.3g/L, ZnSO40.1g/L; and the optimum bottle load was50.8mL in a250mL flask, and theoptimum inoculum volume was10.0%(v/v). The color value of Monascus pigment reachedto (342.24±2.88)U/mL, increased by86.9%than that in the basal medium, when the test fungiwere incubated in150r/min and30℃for7d.(3) Monascus purpureus MY-01was adopted to produce Monacolin K in solid statefermentation, and the fermentation conditions were optimized by the single factor experiment,Plackett-Burman design and RSM. The results showed that the optimal fermentationconditions contained37.77%(v/w) initial moisture content of rice,46.26g/250mL flaskbottling capacity,8.52%(v/w) inoculation volume, pH5,1%(w/w) glucose and1%(w/w)peptone. The Monacolin K reached to (16.67±0.36)mg/g, increased by47.7%than that in thebasal medium, when the test fungi were incubated at28℃for14d.