Optimization of extraction process of flavonoids in Phyllanthus emblica L. by response surface methodology and content determination

This study is done to optimize the extraction process of flavonoids in Phyllanthus emblica L., and determine the quercetin content in the extract. Flavonoids in Phyllanthus emblica L. is extracted by solvent extraction, then, on the basis of single-fact or experiments, the process for extraction of flavonoids in Phyllanthus emblica L. is optimized by response surface design with total flavonoid yield as the response. HPLC is used, with a Kromasil ODS-1 column, a mobile phase of acetonitrile-1 gm/L phosphoric acid solution (30:70) and a detection wavelength of 360 nm. The optimal process parameters for extraction of flavonoids in Phyllanthus emblica L. obtained by response surface methodology are as follows: ethanol concentration of 60.14%, extraction temperature of 80°C, liquid solid ratio of 25: 1 ml/gm and extraction time of 126.87 min. The process conditions could achieve a total flavonoid yield of 8.60%. Quercetin had a good linear relationship within 1.32~23.1 µg (r=0.9998); and average sample recovery was 101.90%, with a RSD of 2.10%. The response surface methodology had practical application value for the optimization of extraction of flavonoids, which can provide the production basis for industrial utilization of abundant Phyllanthus emblica L. resources for total flavonoids extraction. The content determination method established can provide the foundation for the quality control of Phyllanthus emblica L. extract.