Microwave-assisted extraction and in vitro antioxidant activity of Monascus mycelium polysaccharides

Response surface methodology (RSM) was used to optimize the microwave power, extraction time and ratio of water to raw material to obtain a high polysaccharides yield from Monascus mycelium (MMP) by microwave-assisted extraction technique. The optimum extraction conditions were as follows: microwave power 440 w, extraction time 3.6 min and ratio of water to raw material 28 ml/g. Under these conditions, the experimental yield was 11.82%, well matched with the predicted models with the coefficients of determination (R-2) of 0.9949. Furthermore, in vitro antioxidant activities of MMP were investigated including superoxide radical, hydroxyl radical and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical. The antioxidant results showed the MMP exhibited strong hydroxyl radical (73.26% at 100 mg/L) scavenging activity, moderate superoxide anion radicals (83.02% at 0.875 mg/ml) nd DPPH radicals (92.33% at 3 mg/ml) scavenging activities.