A combination of fermentation method and germinated brown rice (Oryza Sativa) to enhance antioxidant activity of angkak

Abstract

This research aimed to enhance antioxidant activities of angkak by a combination of 2-step fermentation and germinated brown rice (Oryza sativa) (GBR). It was showed that an appropriate combined condition of germination time of brown rice and fermentation method of angkak was 48 hours and 2-step fermentation. The highest contents of reducing sugars used by M. purpureus were 99.43 % and the highest pigment intensity, monacolin K and GABA were 3,500.89 unit /g substrate, 99.75 and 154.19 mg/kg dry weight, respectively. Whereas, the lowest IC50 values of DPPH and ABTS were 0.07 and 0.06 mmol Trolox equivalent /mL, respectively. However, the citrinin contents of this product were 12.37 μg/kg dry weight, indicating not exceeded following the maximum allowance level in red fermented rice.