Abstract:

Microfiltration and ultrafiltration membrane separation methods were studied for purifying  toosendanin from crude extracts of the bark of azedarach by microwave-assisted extraction. The polysulfone ultrafiltration membranes  UEOS-503, USIC-503 and UPIS-503 were studied for  separating and purifying toosendanin. The results showed that polysulfone UEOS-503 ultrafiltrating membrane with retenting molecular weight 6 K was much better than USIC-503(10K) and UPIS-503(20～50K) in separating and purifying toosendanin. In order to improve the toosendanin purity and transfer rate, the optimal separating and purifying conditions were investigated and obtained as follows: the raw concentration of toosendanin was 0.369mg／mL, the temperature was 35℃, the operating pressure of 0.10MPa, the cross flow velocity was 6.17×10^-4m／s, and the pH value was 7.0. Under the optimum conditions, the toosendanin transfer rate was 92.8％, and the purity of toosendanin increased from 0.89％ to 15.22％.

Key words: melia azedarach Linn, toosendanin, ultrafiltration membrane, purification