Species Sensitive Electrochemical Method for Enrichment of Azadirachtin-A from Neem Seed

Azadirachtin the active principle of Azadirachta-indica J. Juss. (Neem) ranges from 0.3 to 0.6 percent. A simplified procedure, when compared to established methods, has been developed to enrich azadirachtin-A to 50 percent using minimum possible steps without resorting to chromatographic techniques. It involves additional partition with CCl4 before final extraction which removes most of nimbin, salanin and allied triterpenoids. Enriched product finds immense utility in preparing formulations with high azadirachtin concentration. DCP and DPP polarogrphic methods have been developed for the qualitative as well as quantitative analysis of azadirachtin in plant product and its formulation (Neemgold®). Azadirachtin produces a well defined polarographic wave/peak in 0.1M Tetramethyl ammonium bromide at pH 3.3±0.1 with E½/Ep= -1.48V/SCE. The wave/peak height is found to be proportional to the concentration of Azadirachtin. The developed procedure was used for the analysis of Azadirachtin in extract of Azadirachtin indica (seeds) and market formulation. Statistical treatment of the observed voltammetric data revealed high accuracy and good precision of determination.