CHED 803 |
| Michelle M. Cartagena and Elba D. Reyes. Chemistry Department, University of Puerto Rico, Cayey Campus, P.O. Box 96 La Plata, Puerto Rico, PR 00786 |
| In Puerto Rico, infusions of plants with therapeutic effects are very useful but sometimes dangerous for the health. For many plants used to treat different illnesses, no phytochemical information are reported, therefore, nobody knows of possible secondary effects or side reactions that will happen due to changes in pH or side reactions with other synthetic drugs. The main goal of this research is to study the chemical changes of the plant compounds that have therapeutic effects (metabolites), which are namely ingested by humans. In particular, we want to answer the following questions: 1) Do the compounds present in an active extract suffer chemical changes at different pHs and temperatures? 2) Are all the organic compounds present or extracted from one source present in the infusions prepared by the population? We expect to: a) probe qualitatively if the general organic composition at specific infusions suffers chemical changes with lower or neutral pH’s; b) compare the total chemical compositions of the whole crude MeOH extracts of Citrus aurantium L. and Annona reticulata leaves with the extracted chemical composition in the aqueous phase when the infusions are prepared, and c) characterize the crude extracts presenting chemical changes. Preliminary TLC results, analyzing infusion extracts from leaves of Citrus aurantium L. and Annona reticulata (after mimicking human digestion, specifically stomach and plasma pH and corporal temperature) reveals irreversible chemical changes when the pH rises to 7.4. These preliminary results demonstrate that chemical changes could be occurring during the bioassays implicating that biological activity could be due to the chemical changes promoted by the extracts instead of natural metabolites. Extracts presenting chemical changes are submitted to Probit analyses, using brine shrimp as live source to probe citotoxicity. ED50 values and partially characterization of organic compounds using chromatographic (TLC, CC, GC) and spectroscopic techniques (IR, MS) will be presented.
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Undergraduate Research Poster Session: Organic Chemistry
2:00 PM-4:00 PM, Monday, March 29, 2004 Anaheim Convention Center -- Hall A, Poster
Division of Chemical Education |