Abstract: Supercritical CO₂ was used to extract the effective ingredient in Chinaberry bark. Lieberman reaction, Salkwoski reaction and dimethylaminobenzaldehyde reaction were used to identify toosendanin.Uniformity design was used for the experiment scheme. Extraction rate (Y₁) was measured by means of material weight loss. Absorbency (Y₂) at 510 nm was measured to indicate the relative concentration of toosendanin in the extraction. Correlation equations between experimental conditions and Y₁ and Y₂ have been described respectively.Results showed that optimum extraction conditions of toosendanin are:pressure 28 MPa, temperature 35℃ for Y₂, time 5 h and without addition of high-polar modifier.

Key words: Melia azedarach L. bark, supercritical carbon dioxide extraction(SCDE), uniformity design