Determination of Monacolin-k In Red Yeast Rice Extract
Weigh accurately400.0mg～600.0mg(W2) of test sample to previously dried 50ml volumetric flask add 30ml 75%methanol,dissolve and sonicate for 50mins at room temperature,add 75%methanol to close the scale,sonicate for 10mins ,After cool at room temperature,add 75%methanol to the scale,At 3500 r/min rotation speed centrifuge for 10 min.Take that the supernatant fluid 0.45um microporous membrane filtration.
Weigh accurately 4mg of Monacolin-k to the previously dried 100ml volumetric flask by 0.2 mol/L sodium hydroxide, sonicate for 1 h in 50℃ , cool at room temperature and putting 1 h.
Column: C18 250mm×4.6mm
Flow rate: 1.0 mL/min
Detection: 238 nm
Injection Volume: 20μl
Mobile phase: Methanol: water: phosphate = 385-385:0.14 (volume fraction)