Production of azadirachtin by callus cultures from Azadirachta indica A. Juss.

Due to environmental factors and genetic reasons, the content of azadirachtin varies considerably. Also, A. indica does not grow in moderate climates. Therefore, in order to obtain constant amounts of standardized quality, it seems appropriate to employ tissue culture techniques for its production. Here, it was investigated, if callus cultures (CC) derived from various explants produce azadirachtin. Explants from plants of different geographical origins (Nigeria, Nicaragua, Cuba) and from different parts of the plant (leaf, bark) were incubated, on a Murashige and Skoog medium (MS) at 26+/-1 degrees C, in the dark. After callus initiation, the calli were subcultured several times. Callus tissues were extracted with petroleum ether and distilled water, followed by a solid phase extraction. Analyses of the calli as regards their azadirachtin content were carried out using TLC and HPLC, respectively. CC of A. indica are capable of producing azadirachtin depending on their age, the cell line, the medium and the carbohydrate source employed. CC subcultured thrice produced more azadirachtin than CC subcultured once or twice.