Banca de DEFESA: TCHIARA MARGARIDA ALVES TENÓRIO
Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.STUDENT : TCHIARA MARGARIDA ALVES TENÓRIO
DATE: 28/06/2024
TIME: 14:00
LOCAL: Auditório do Departamento de Química
TITLE:
BIOPROSPECTING OF Ipomoea L. SPECIES THROUGH METABOLOMIC TECHNIQUES: SEARCH FOR MOLECULES WITH INSECTICIDAL POTENTIAL AGAINST Tetranychus urticae
KEY WORDS:
pomoea (L.); ethanolic extract; essential oil; insecticidal activity; acaricidal activity; abiotic estresses.
PAGES: 145
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Química dos Produtos Naturais
SUMMARY:
Plant secondary metabolites play an important role in defending against environmental stresses, contributing to their growth and survival. Thus, an investigation using a metabolomics approach makes it possible to completely map the main metabolic pathways active in certain cultivation conditions of an organism. The objective of this study is to map the chemical profile of the species Ipomoea alba, I. batatas, I. carnea, I. indica and I. pes-caprae using different simulated conditions of biotic and abiotic stresses and thus be able to stimulate the production of bioactive metabolites. The Ipomoea species were grown in a greenhouse, divided into different groups and each group was subjected to a stress condition. After 24 hours of stress, the volatile compounds in Ipomoea leaves were directly analyzed by HS/GC-MS. The results of the chemical compositions were analyzed using multivariate techniques, such as PCA, heatmap and molecular network. The PCA and heatmap studies showed qualitative and quantitative differences in the chemical composition of volatiles of Ipomoea species subjected to different stresses. Among the compounds identified in the essential oils of the leaves and flowers of the selected species, β-caryophyllene (Leaf: 42.10-7.00%; Flower: 36.50-6.4%) was identified in all analyses. In the species of I. alba, UV stress showed greater production of the compounds β-elemene (22.69%), bicyclogermacrene (23.16%) and germacrene D (8.95%) compared to the other stresses, however, they were not larger compared to the Control samples. γ-Murolene was the majority constituent for all samples of I. indica and I. batatas, a higher percentage was observed when the species were stressed with methyl jasmonate. For I. carnea, the compound that presented the highest percentage was germacrene D (56.15-38.17%) for all analyses, however it was observed that stressed species reduced the percentage of the compound. I. pes-caprae showed greater diversity of monoterpene compounds when the plant was subjected to stress. Molecular networks were generated based on spectral similarities between components to verify the molecules that are part of the biosynthetic pathways. The residual contact test of the ethanolic extract of I. indica leaves against Tetranychus urticae showed an LC50 (2.46 mg/mL) close to the botanical acaricide, Azamax®. Therefore, it was found that biotic and abiotic stresses cause quantitative and qualitative changes in the chemical composition of the volatiles of species of the genus Ipomoea and the I. indica extract has the potential to become a botanical acaricide for the control of T. urticae.
COMMITTEE MEMBERS:
Presidente - CLAUDIO AUGUSTO GOMES DA CAMARA
Interno - JOAO RUFINO DE FREITAS FILHO
Externo ao Programa - 2002989 - ANDRE AUGUSTO PIMENTEL LIESEN NASCIMENTO - UFRPEExterna à Instituição - CAROLINA ALVES DE ARAUJO - UFRPE
Externo à Instituição - RODOLFO RODRIGUES DA SILVA - UFRPE