Optimization of Fermentation Conditions for Higher Monacolin K Production by <i>Monascus purpureus</i>

Monacolin K is a secondary metabolite of Monascus fermentation with lowering blood fat, cholesterol and blood sugar. The culture substrates and fermentation conditions were optimized by means of L 9 (3 3 ) orthogonal experiments. The optimized fermentation conditions were studied and concluded: initial moisture content 50%, material thickness 4 cm and fermentation time 13 days. Using rice as substrate, the maximum yield of monacolin K was 2.50 mg/g in the optimized conditions. Using glutinousrice as substrate, the maximum yield of monacolin K was 2.71 mg/g in the optimized conditions. The founding determined that glutinousrice was used as substrate in solid state fermentation by Monascus purpureus to produce monacolinK.