Biological Characteristics, Stability And Security Of Yellow Pigment Producer Strain Monascus HB-5

A new mutant of Monascus mold capable of producing yellow pigment was selected and studied in this paper. The biological characteristics of Monascus HB-5 which produced yellow pigment were studied. Aerial hypha grew rapidly and strongly, formed a nummular apophysis with yellow in the center and white on the brim. The conidia were produced in the agamogenesis process,and the size was (4～10) × (5～12) μm. Globose ascocarps were produced in the sexual reproduction process, and the size was (15～19) × (20～24) μm.It was shown that the optimal growth temperature of Monascus HB-5 was 30～32℃, pH was 4.0～5.0. The optimal carbon source was corn and the nitrogen source was NH4NO3. Its color tone was yellow, and the single absorption peak was on 370nm. The key parameters of the pigment in the submerged culture were examined, including pH, carbon resources and nitrogen resources. The results showed that a high concentration of yellow pigment could be produced by this strain under the conditions of the optimal inoculum size of 10%(v/v), pH 4.6～5.7,the results of the orthogonal experiment showed that the optimal condition for yellow pigment production was corn: 10%,NH₄NO₃: 0.2%, KH₂PO₄: 0.2%, MgSO₄: 0.08%. The color value of the yellow pigment produced by Monascus was 200u/ml and it could be obtained from a flask under these conditions . The cultivation conditions for solid-state fermentation for producing yellow pigment by Monascus HB-5 was studied. The optimal fermentation parameters were:initial water content of substrate was 50%,add 6% water when 12h,36h,48h in the cultivate process. And peptone3%,corn3%,yeast extract1% were able promote the production of yellow pigment. At optimized culture conditions, the productivity of yellow pigment was 1032u/g.