Study on the Extraction Process for Carnosic Acid from Rosmarinus officinalis Linn

Objective To optimize the extraction process for carnosic acid from leaves of Rosmarinus officinalis Linn. Methods With the extraction rate of carnosic acid as quantitative index,the best extraction solvent and extraction method were identified by single factor experiments. And then, the effects of extraction time,solid-liquid ratio and extraction times on extraction rate of carnosic acid were investigated by orthogonal tests.Results The optimal extraction technology was as follows: ethyl acetate extracting with material and solvent ratio of 1:14, ultrasonic extraction for 4 times,wand 75 min each time. Under these conditions, the average extraction rate of carnosic acid was up to 2.479%. Conclusion The optimal extraction process for carnosic acid from R. officinalis was reproducible and stable.