| 摘要 |
<p>PURPOSE: Provided are a stabilized extracts of the seeds of the neem tree(Azadirachta indica Juss) which provide materials useful as insecticides, a composition containing the extract, and a method for using the same. CONSTITUTION: The method comprises the steps of (a) deoiling ground neem seeds, neem kernels or partially dehulled seeds using hexane to obtain a deoiled cake, (b) extracting the deoiled cake with methanol followed by filtration, (c) either (i) removing the methanol to obtain a dry extract, dissolving the dry extract in methanol, preferably at a weight ratio of extract to methanol of 3/7, and adding water to a final methanol/water ratio of from 5/95 to 45/55, preferably 35/65 (v/v), or (ii) evaporating the methanol to obtain a concentrate containing over 65% volatiles, and adding water to obtain a final methanol/water ratio of from 5/95 to 45/55, preferably 35/65 (v/v), (d) separating the aqueous methanolic phase from any solid impurities, (e) diluting the aqueous methanolic mixture with an aqueous salt solution, (f) extracting the dilute solution with a water immiscible solvent, preferably ethyl acetate, and (g) drying the resulting organic solution and, if desired, removing the solvent.</p> |
