Fermentation Regulation Of The Breeded Of Monascus Strain For High Yield Water-soluble Yellow Pigments And Their Purification

Monascus pigment which produced by microorganism is a natural pigment with wide application prospect.In recent years,as the research onMonascus pigment moves along,the advantage of water-soluble Monascus pigment and Monascus yellow pigment have become increasingly prominent.Therefore,the research on water-soluble yellow pigment is of great theoretical and economic benefits.In this paper,we mainly research on the following aspect: screening and breeding Monascus strains with high yield of water-soluble yellow pigment,optimization of fermentation conditions of high yield strain,researching separation,purification and properties of fermented broth yellow pigment.Those studies provide the reference for the theoretical research and production and development of water-soluble yellow pigment.One of the pivotal problems on production of Monascus pigment was studied,starting from the dominant Monascus strains breeding,selected a Monascus strain(Monascus ruber CGMCC 10910)with high yield of water-soluble yellow pigment and no citrinin.The capacity of water-soluble yellow pigment production ofMonascus ruber CGMCC 10910 increased by 72.37% than the original bacteria.Through controlledMonascus fermentation culture medium components(carbon source and nitrogen source)and high density cultivation mode,the metabolism(high yield of water-soluble yellow pigment and low yield or not produce citrinin)impacts and regulation mechanism were studied under high cell density fermentation of Monascus.Experimental results showed that carbon source and nitrogen source fromMonascus fermentation culture medium could affect the growth of bacteria and the composition of extracellular and intracellular pigment.Inorganic amino nitrogen and glucose were more advantageous to the synthesis of water-soluble Monascus yellow pigment,water-soluble Monascus yellow pigment could be a large number of accumulation under high glucose concentration and low ORP value,while high glucose concentration might lead to the transformation of the yellow pigment or degradation in the late feed fermentation of Monascus ruber CGMCC 10910,we speculated that this phenomenon might be related to redox level of fermentation broth and high sugar stress reaction.In this paper,the purification effect of different polar macroporous resins,activated carbon and silica gel were researched on water-soluble Monascus yellow pigment from high glucose fermentation broths.Experimental results showed that nonpolar macroporous adsorption resin DA201-C had good adsorption and desorption performance to water soluble Monascus yellow from fermented liquid.After water solubleMonascus yellow pigment was adsorbed and desorbed dynamically by macroporous resin DA201-C,the pigment recovery rate could reach 96.99%,desalination rate could reach 99.44%,and desugarization rate could reach 92.52%.Water-soluble Monascus yellow pigment acquired by preliminary separation of resin,which present a series of refined separation of column chromatography,thin-layer chromatography,and the preparation HPLC,could be obtained a relative single water-soluble yellow pigment C.Its purity could reach more than 98% and the color value could reach 18996.96 AU387 / g.The physical and chemical properties analysis found that the pigment Cwas stableunder the condition of low pH(2.0),and also has good stability under the sunlight and the fluorescent lamp,while the pigment should avoid put in the ultraviolet or high temperature environment for long time preservation.Biological activity analysis found that the pigment has a role in the oxidation resistance and blood glucose-lowering,the IC50 of alpha glycosidase enzyme inhibition was about 2.15 AU387/mL.In addition,the food additive stability testing found citric acid and vitamin Ccould improve the thermal stability and light stability of the pigment in a certain extent,and several other additives had no obvious effect on the stability of the pigment.