Stability of the natural insecticide azadirachtin in aqueous and organic solvents

Abstract

The natural insecticide azadirachtin is most stable in mildly acidic aqueous solutions between pH 4 and 6 at room temperature. It is unstable in mildly alkaline and strongly acidic solutions. It is stable when stored in neutral organic solvents at room temperature for months. While it is relatively stable to heating in the seeds or as a pure solid, it is rapidly destroyed or altered by heating in aqueous solution and methanol. In methanol at 90°C it is quantitatively converted to 3-acetyl-1-tigloylazadirachtinin. © 1998 SCI