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Previous issue date: 2011-05-31 / Licania rigida Benth., Licania tomentosa (Benth.) Fritsch, and Couepia impressa
Prance (Chrysobalanaceae family) plants have long been used medicinally by
the people from Northeastern Brazil. Crude extracts and infusions of these
plants have been applied in the treatment of several conditions such as
diabetes and rheumatism, degenerative diseases with involvement of reactive
oxygen species (ROS). The aim of this study was to evaluate the aqueous,
ethanolic, and hydroethanolic leaves extracts antioxidant capacity of these
species, using several in vitro assay systems (reducing power, DPPH?
scavenging, the ?-carotene linoleate model system and lipid peroxidation
inhibition in rat brain homogenate, using thiobarbituric acid reactive substances
- TBARS). The oral acute toxicity of aqueous extracts was also evaluated in
vivo. Results revealed that these extracts possess a potent reducing power and
DPPH scavenging ability, as well as the ability to prevent TBARS formation in
rat brain homogenate in a concentration-dependent manner. Regarding in vivo
oral acute toxicity of the aqueous species extracts, no toxic effects were
observed upon evaluating physiological, hematological and biochemical
parameters. The presence of high levels of phenolics and flavonoids was
determined mainly in the ethanol extract. However, the C. impressa
hydroethanolic extract, fractionated with hexane, chloroform and ethyl acetate
for analysis by NMR 1H, showed more efficient results than the reference
antioxidant Carduus marianus. The classes of organics compounds were
determined were phenolics in the fraction of ethyl acetate and terpenes in
chloroform and hexane fractions. The ethil acetate fraction had the highest
content of flavonoids and increased scavenging capacity of DPPH?, possibly by
the presence of phenolic compounds. Therefore, a detailed investigation of the
phytochemical composition and in vivo study of the C. impressa hydroethanolic
extract is suggested to characterize the active compounds of the species / Licania rigida Benth., Licania tomentosa (Benth.) Fritsch, e Couepia impressa
Prance (fam?lia Chrysobalanaceae) s?o plantas utilizadas pela medicina
popular do Nordeste do Brasil, sob a forma de extratos e infus?es para o
tratamento do diabetes e reumatismo, doen?as degenerativas com
envolvimento de esp?cies reativas de oxig?nio (ERO). O objetivo deste estudo
foi avaliar a capacidade antioxidante dos extratos aquoso, etan?lico e
hidroetan?lico das folhas dessas esp?cies, utilizando v?rios sistemas de ensaio
in vitro (poder redutor, capacidade de sequestro do DPPH?, o sistema ?-
caroteno/?cido linoleico e a inibi??o da peroxida??o lip?dica em homogenato de
c?rebro de ratos, utilizando as subst?ncias reativas do ?cido tiobarbit?rico -
SRAT). A toxicidade oral aguda dos extratos aquosos tamb?m foi avaliada in
vivo. Os resultados revelaram extratos com alto poder redutor, capacidade de
sequestro do DPPH? e de prote??o no sitema ?-caroteno/?cido linoleico, bem
como a capacidade de impedir a forma??o de SRAT em homogenato de
c?rebro de ratos, de maneira concentra??o-dependente. Quanto ? toxicidade
oral aguda in vivo dos extratos aquosos, nenhum efeito t?xico foi observado em
rela??o ?s avalia??es fisiol?gica, hematol?gica e bioqu?mica. A presen?a de
elevado teor de compostos fen?licos e flavonoides foi determinada
principalmente no extrato etan?lico. Entretanto, o extrato hidroetan?lico de C.
impressa, fracionado com hexano, clorof?rmio e acetato de etila para a an?lise
por RMN 1H, mostrou resultados mais eficientes do que o antioxidante de
refer?ncia Carduus marianus. As classes de compostos org?nicos
determinados foram fen?licos na fra??o acetato de etila e terpenos nas fra??es
hex?nica e clorof?rmica. A fra??o acetato de etila apresentou o maior teor de
flavonoides e maior capacidade de sequestro do DPPH?, possivelmente pela
presen?a de compostos fen?licos. Portanto, uma detalhada investiga??o da
composi??o fitoqu?mica e estudo in vivo do extrato hidroetan?lico de C.
impressa ? sugerida para caracterizar os compostos ativos da esp?cie
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/13510 |
| Date | 31 May 2011 |
| Creators | Macedo, Jos? Benilson Martins |
| Contributors | CPF:20054548420, http://lattes.cnpq.br/0321740024191482, Langassner, Silvana Maria Zucolotto, CPF:81995725072, http://lattes.cnpq.br/7390416147619446, Klein, Sibele de Oliveira Tozetto, CPF:21504953843, http://lattes.cnpq.br/6285491619832020, Almeida, Maria das Gra?as |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Ci?ncias Farmac?uticas, UFRN, BR, Bioan?lises e Medicamentos |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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