The present invention relates to a novel method for the preparation of silver nanoparticles using plant extract. The present invention more particularly relates to a method for the synthesis of silver nanoparticles using ethanolic extract of Zanthoxylum alatum leaves. The 2-undecanone compound is extracted from the leaves of Z. alatum and its carboxy derivative. The nanoparticles formed are of a size in the range of 10-40 nm of the derivative prepared. The nanoparticles will be useful as flavouring agents in the confectionery industry and in the manufacturing of soft drinks and also used as a mosquito repellant.
