A new method for extracting oridonin from rubescens and processing extracts was studied. The solvent back-mixing method was used to extract oridonin

and the extract with higher target product concentration was obtained. The optimum conditions for the extraction of oridonin were found by the single factor method:the ratio of material to solvent was 1 (g):8 (ml); the oridonin content contained in mixed solvent was 652 mg/L; temperature was 35℃; pH was 5.5. By adding water to change the polarity of the extracted solvent

and accompanied by low-temperature fractional precipitation. The remaining extracted solvent was evaporated under reduced pressure to obtain an extractum of 22.2% of oridonin

which was significantly higher than that reported in the literature. After pretreatment

the extracted had almost no loss of oridonin during the desolvation process

which solved the problem of large loss of oridonin in the conventional concentration process.