Biotransformation of Toxic Pyrrolizidine Alkaloids From Prestonia portobellensis by Tithorea tarricina Caterpillars
EPA Grant Number: MA916359Title: Biotransformation of Toxic Pyrrolizidine Alkaloids From Prestonia portobellensis by Tithorea tarricina Caterpillars
Investigators: Ochaney, Monica
Institution: Florida International University
EPA Project Officer: Willett, Stephanie H.
Project Period: January 1, 2004 through December 31, 2006
Project Amount: $60,215
RFA: GRO Graduate Fellowships (2004)
Research Category: Academic Fellowships , Biology/Life Sciences , Fellowship - Natural and Life Sciences
Description:
Objective:Many plants employ toxic compounds to defend against predators and pathogens. Some arthropods, particularly butterflies and their larvae, have coevolved to use phytotoxins for defense against predation. Butterflies belonging to the subfamily Ithomiinae of the Nymphalidae sequester secondary metabolites from plants, including pyrrolizidine alkaloids (PAs). The objective of my research project is to determine the fate of these alkaloids. PAs may be used directly, detoxified, or employed by caterpillars to synthesize new compounds.
Approach:Tithorea tarricina caterpillars obtain PAs from the host plant, Prestonia portobellensis (Apocynaceae). First, PAs in P. portobellensis plants will be compared with those found in T. tarricina caterpillars. This will be done to determine if T. tarricina larval PAs are the same as those found in P. portobellensis. Second, the qualitative and quantitative variation of PAs among larval stages in T. tarricina caterpillars will be assesed. To determine alkaloid profiles of T. tarricina caterpillars and P. portobellensis, collections will be made at Gamboa in the Republic of Panama. I will sample during both the rainy and dry season and for 1 month in each season. The research will determine intraspecific alkaloid variation in both P. portobellensis and T. tarricina and compare alkaloid profiles of these species. PA profiles will be analyzed using gas chromatography.
Supplemental Keywords:fellowship, phytotoxins, pyrrolizidine
alkaloids, defense mechanisms, biotransformation, predator defense, host plants, Tithorea
tarricina , Prestonia portobellensis,
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Ecosystem Protection/Environmental Exposure & Risk, Scientific Discipline, RFA, Ecosystem/Assessment/Indicators, exploratory research environmental biology, Ecological Indicators, Biochemistry, Ecology and Ecosystems, pyrrolizidine alkaloids, biotransformation, adaptation, phytotoxins, caterpillars, adaption mechanisms