This study optimised the ultrasound-assisted extraction (UAE) conditions to achieve maximal recovery of
active monacolins with minimal contents of citrinin from red yeast rice (RYR). A central composite design
after a full factorial design was utilised to examine the different UAE parameters. The studies revealed
that HAc%, extraction time and EtOH% had significant influences on the recovery yield of monacolins,
while HAc% and EtOH% were key factors for the elimination of citrinin. The resulting optimal conditions
were as follows: ultrasound power of 250 W, HAc% of 7.7%, RYR amount of 0.2 g (solvent-to-solid ratio
40 mL/g), extraction time of 50.7 min, EtOH% of 57.2% and extraction temperature of 20 C. Under these
conditions, at least 94.7% of monacolins was recovered and 87.7% of citrinin was removed from RYR. This
optimised UAE condition was further evaluated for potential industrial application in manufacturing of
RYR as pharmaceuticals and nutraceuticals.
2014 Elsevier Ltd. All rights reserved.