The single-factor experiment and an orthogonal experiment design were adopted to optimize the extracting technology of polyphenols from adlay. The results showed that, the impact order of the influence factors was ethanol concentration > extraction time > extraction temperature, and that ethanol concentration and extraction time have significant difference (p<0.05). The optimum extraction conditions were ethanol concentration 60%, extraction time 1.5 h, extraction temperature 40 oC and ratio of liquid to material 15:1. Under the optimized conditions, the yield of total polyphenols from adlay was 2.84 mg/g.
Keywords: Adlay, Extraction process, Polyphenols, optimization
