Banca de QUALIFICAÇÃO: RUSCELI DIEGO DE ARAUJO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : RUSCELI DIEGO DE ARAUJO
DATA : 17/08/2017
HORA: 09:30
LOCAL: Auditório do laboratório de Química 3
TÍTULO:

Chemical and biological research of Eugenia luschnathiana: toxicity, antioxidant profile and triterpenes Oleanane and
Ursane

PALAVRAS-CHAVES:

Antioxidant activity; toxicity; oleanane; ursane

PÁGINAS: 170
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
RESUMO:

Since ancient times, plants have been known as a rich source of the most diverse substances, with wide chemical structures and biological properties. Its use
in popular medicine in the form of teas, ointments and infusions is disseminated throughout the world, coming to be in certain underdeveloped countries one
of the main forms of treatment. Among many families belonging to the plant kingdom, we can highlight the family Myrtaceae. It is in the group of the 10
largest families of angiosperms in the world and several studies have already been carried out with genera belonging to this family. Among these genres
stands out the genus Eugenia, which like other family species, develop well in tropical regions such as South America and Asia. Diuretic, anti-inflammatory,
antimicrobial, diabetes-fighting activities, among others, have already been reported for the genus, so that some species were selected by the Renisus
program as target plants for chemical and biological studies. Literature reports this genus as a source of chemical structures belonging to the classes of
flavonoids, coumarins, derivatives of floroglucinol, tannins and terpenes, thus representing a rich source of the most diverse secondary metabolites. In this
way the present work proposes the chemical and biological investigation of Eugenia luschnathiana, species in which there are still no reports of
phytochemical studies in the literature. The evaluation of antioxidant activity against the DPPH radical of ethanol extract of leaves (ELFE) and stem (ELCE)
and partition fractions hexanic (H), chloroform/dichloromethanolic (C)/(D), ethyl acetate (AcOEt) and hydroalcoholic (HA) shown good results, where we
can highlight the ELCE-AcOEt and ELCE-HA fractions with concentrations of IC 50 = 59,755±0,756 μg/mL and 37,451±0.001 μg/mL respectively. From the
leaves ELFE-AcOEt fraction and the decote (ELD) were obtained the best results, with values IC 50 = 56.913±0.164 μg/mL and 66,114±0.052 μg/mL
respectively. The toxicity test against microcrustacean A. salina showed that all fractions are nontoxic, which highlights the possible use of these plants in
folk medicine. However, the essential oil was highly toxic at a concentration of 0.00702 μg/mL. The GC-MS analysis of essential oil, saponifiable and

unsaponifiable compounds allowed the identification of 25 molecules. The majority composition of oil consisted of oxygenated and non-oxygenated
sesquiterpenes; 23 saponifiable and 26 unsaponifiable compounds, proving the lipid richness present in this specimen. The chromatographic procedures
performed with the stem extract allowed the isolation of the triterpene of oleanane profile, arjunolic acid (EL-1), and by acetylation reaction its acetylated
derivative (EL-2). From the leaves were isolated a mixture containing the oleanolic acid and the major ursolic acid (EL-3), besides the unpublished substance
in the genus Eugenia the 3-p- cumaroil-tormentic acid, of ursano structure. More structures with triterpenic or steroidal profile are in characterization phase,
thus confirming the present genus as source of this type of metabolites.

MEMBROS DA BANCA:
Externo ao Programa - 1569330 - GRAZIELLE TAVARES MALCHER
Presidente - 1569526 - RENATA MENDONÇA ARAUJO