Optimum conditions of extracting and detecting rutin from stigma maydis by response surface analysis

The purpose of this study was to explore optimum conditions of extracting and detecting rutin from stigma maydis. Four factors, including ethanol volumteric concentrations, liquid to solid ratio, reflux time and ultrasonic time were selected to optimize the extraction process of rutin by response surface method. Rutin samples extracted by the optimum process were determined by ultraviolet and infrared spectrometry, and HPLC. The experimental results showed that the best conditions of extracting rutin from stigma maydis were ethanol concentration: 49%, liquid to solid ratio: 30 mL∶1 g, reflux time: 1.7 h and ultrasonic time: 36 min. Under these processing conditions, the rutin content in stigma maydis was 12.152 mgg-1. The results from ultraviolet and infrared spectrometry indicated that the main functional groups were absorbed significantly. And HPLC detection showed a high repeatability. In conclusion, the optimum conditions selected here on the extraction of rutin from stigma maydis was efficient and provided references to the further study of stigma maydis.