Abstract

Looking for new biologically active molecules useful as therapeutic agents, active against several diseases or as useful agents to control pest insects, fungi, bacteria, or other organisms, remains a global research priority. The essential strategy in order to identify these new molecular entities remains focused on the study of secondary metabolites present majority and minority in endemic plants. The geographical and climatic features of Chile have allowed the development of a unique flora, this being an important natural resource of the country. Nonetheless, the percentage of species that have been studied from the standpoint of biological activity and potential agrochemicals is quite limited. Endemic Chilean plants of the family Rhamnaceae are an interesting resource to study, because there is very little background on it. Studies of other rhamnaceous plants indicate the presence of alkaloids (benzyltetrahydroisoquinoline, aporphine and cyclopeptide alkaloids) that have shown an interesting activity on different receptors. It is known that this receptor is involved in feeding reflexes and/or insecticidal activity in insects exhibited by different types of compounds. The following plants will be examined: Retanilla ephedra and R. trinervia; Rhamnus diffusa; Talguenea quinquenervia and Trevoa trinervia. In order to examine the biological activity of the plant components, we will isolate and characterize of compounds from the plants with emphasis in the alkaloids and evaluate the insecticidal, IGR, antimicrobial activities and inhibition of enzymes such as acetylcholinesterase and tyrosinase that play an important role in the development of insects. To perform activity assays, we have selected insects and microorganisms that often attack crops of fruits and vegetables, eg Xanthographus Naupactus, Pieris brassicae, Spodoptera frugiperda. Finally, this project has been integrated phytochemical and botanical studies, with the ultimate purpose of sustainable and biorational alternatives that respect the environment, the current indiscriminate, not selective, inducted resistance and deleterious to the environment, pesticides synthetic, in the fight against insect pests that are important to the economy of the regions involved.