Influence of operating parameters on the use of the microwave-assisted process (MAP) for the extraction of azadirachtin-related limonoids from neem (Azadirachta indica) under atmospheric pressure conditions

The use of the microwave-assisted process (MAP) for the extraction of azadi rachtin-related limonoids (AZRL) from various parts of the neem tree was in vestigated under different operating conditions. The influence of microwave power, solvent, and irradiation time on the recovery of AZRL was studied. The efficiency of the microwave-assisted extraction (MAE) of the seed kerne l, the seed shell, the leaf, and the leaf stem was compared to that of conv entional extraction methods. The content of AZRL in the extracts was estima ted with a vanillin-based colorimetric assay and a multivariate calibration technique. The results showed that the MAE technique can enhance the extra ction of AZRL from different parts of neem possessing microstructures. Inve stigation of the influence of the solvent also indicted that the solvent us ed not only influences the efficiency but also affects the selectivity of t he MAE.