Response Surface Method for Microwave-Assisted Extraction of Rosmarinic Acid in Perilla Frutescens Leaves

Microwave-assisted extraction of rosmarinic acid in perilla frutescens leaves was optimized by response surface method.The optimal process conditions were as follows,the microwave power 560 W,processing time 4.5 min,solid-liquid ratio 1∶33(1 g sdid in 33 mL solvent).Under the optimal conditions,the rosmarinic acid yield reached 2.55 g/mg.Compared with conventional extraction process of rosmarinic acid in perilla frutescens leaves,microwave-assisted extraction process is feasible.