Lactone Glycoside in Cleistanthus collinus (Euphorbiaceae), an Effective Insecticidal Principle

摘要

Non-protein amino acids, which explicit toxic actions against insect pests are the most common broad-spectrum bioactive secondary metabolites present in majority of plant species. Apart from these, plants also produce glycosides, tannins, flavonoids,phenols, lignins, terpenoids and saponins to deter insects. Chemical structures of thousands of these bioactive compounds are still unexplored. Intensive study on the structural elucidation of those bioactive compounds not only yields a model for synthesis of a new insecticidal molecule but also prevents the excessive usage of biomass. Hence, the present study was carried out to characterize the structure of the insecticidal principle from the leaf extracts of Cleistanthus collinus Benth (Euphorbiaceae), a shrub predominant in Eastern Ghats of Tamil Nadu, India, which was proved to have potential biocidal activity against various stages of tobacco caterpillar, Spodoptera litura Fab. (Arivudainambi, 2002). Characterization of the insecticidal principlewas done in four steps viz., extraction, fractionation, identification and structural elucidation.