Optimization of production of monacolin K from gamma-irradiated Monascus mutant by use of response surface methodology.
Monascus isolate number 711, which is capable of producing monacolin K as an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, the key enzyme of cholesterol synthesis, was isolated from Ang-kak, the red yeast rice koji. To increase the monacolin K-producing activity of the strain, spore suspensions of the strain were subjected to gamma-irradiation. One thousand mutants were generated via gamma-irradiation and screened using bioassay and high performance liquid chromatography analysis. Several mutants with higher productivities of monacolin K than that of the parent strain were primarily selected. Mutant KU609 was finally selected because of its characteristics of high monacolin K production and non-citrinin-producing activity under our test conditions. Response surface methodology was used to analyze the effect of culture medium on the production of monacolin K in mixed solid-state cultures. The optimal values of nutritional ingredients for the maximal production were soytone, glucose, MgSO4, and barley at concentrations of 0.5 g, 0.48 g, 0.053 g, and 9 g, respectively. The final monacolin K production of Monascus KU609 was increased almost 100-fold compared to that of the parent strain.
Suh
Soo Hwan
SH
Graduate School of Biotechnology, Korea University, Seoul, Republic of Korea.
Rheem
Sungsue
S
Mah
Jae-Hyung
JH
Lee
Woosun
W
Byun
Myung-Woo
MW
Hwang
Han-Joon
HJ
D002851:Chromatography, High Pressure Liquid; D002953:Citrinin / Q000032:analysis; D003470:Culture Media; D005720:Gamma Rays; D005947:Glucose; D001467:Hordeum; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D008148:Lovastatin / Q000032:analysis / Q000096:biosynthesis*; D008278:Magnesium Sulfate; D015233:Models, Statistical; D032741:Monascus / Q000235:genetics* / Q000378:metabolism* / Q000528:radiation effects; D009154:Mutation; D013025:Glycine max; D013172:Spores, Fungal / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects
D003470:Culture Media; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D002953:Citrinin; D008278:Magnesium Sulfate; D008148:Lovastatin; D005947:Glucose