Phytochemical and Insecticidal Studies of Saussurea lappa

Saussurea lappa (S. lappa) is an herb that is indigenous to the Himalayan region (India, Pakistan, and China). The roots of this plant are used in agricultural fields and stored with woolen clothing due to its insecticidal properties. Literature studies have shown that two terpene derivatives found in this plant (costunolide and dehydrocostus lactone) are known to exhibit insecticidal activity. In the previous year, crude extracts of S. lappa using various solvents (water and ethanol), in addition to sequentially extracting S. lappa with solvents of increasing polarity (hexane, ether, ethyl acetate and ethanol) were concentrated and then evaluated for the presence of saponins, tannins, flavonoids, alkaloids, carbohydrates, and terpenoids using standard tests. In continuation of this study, the pesticidal effects associated with increasing concentrations of the ethanolic crude extract were investigated with Drosophila melanogaster. Within 12 hours of oviposition, D. melanogaster eggs were tested against 12.5, 25, and 50 mg/ml concentrations of the crude ethanolic extract to evaluate its effect on larvae growth over 2, 3, and 4 days post-oviposition. Following larval extraction, the resulting lengths were measured and analyzed. The results of the preliminary bioassays will be presented.