Hot-water extracts of neem bark

摘要

Hot-water extracts of the neem bark produced by treating the bark of neem with water at a temperature from 0 DEG to 40 DEG C. and subjecting the residue from said pre-extraction treatment to extraction treatment with hot water. Purification of the extract thus produced by means of alcohol precipitation or dialysis gives products of a higher purity. Moreover, treatments prior to the pre-extraction treatment with water at 0 DEG -40 DEG C. with a non-polar organic solvent having a dielectric constant of 10 or lower and a polar organic solvent having a dielectric constant from 15 to 35 yields neem extracts of a further higher purity. The hot-water extracts of the neem bark according to the present invention possess activity against mouse L-5178Y cells and transplanted sarcoma 180 tumors.