Banca de QUALIFICAÇÃO: LUCIANA FENTANES MOURA DE MELO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : LUCIANA FENTANES MOURA DE MELO
DATA : 01/12/2017
HORA: 09:30
LOCAL: sala Carl Von Dietrich
TÍTULO:

Prospection of biomolecules with biological activities from Coccoloba alnifolia Casar

PALAVRAS-CHAVES:

antioxidant potential; cell lineages, C. elegans, wheat coleoptile

PÁGINAS: 80
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
SUBÁREA: Química de Macromoléculas
RESUMO:

The use of medicinal plants has been a common practice since antiquity. This knowledge has been based on the experience that it has been passed on many generations. And this may be the starting point for biochemical and pharmacological studies of the active principles. These molecules come from the secondary metabolism from plants and it usually is a response to environmental conditions (biotic or abiotic stress). The Mata atlântica biome has a rich flora, which needs to be studied for its biological activities, and the potential to find new biomolecules. In order to do this, six extracts (hexane, chloroform, ethanolic, methanolic, final water and aqueous) were obtained from Coccoloba alnifolia leaves and then it was evaluated the antioxidant and the biological potential using different in vitro and in vivo systems. First, it was measured the sugar content, proteins and phenolic compounds. Based on these results, qualitative experiments were carried out to determine the secondary metabolites present in these extracts. It was detected the presence of phenols, flavonoids, saponins, triterpenic and steroidal nuclei and unsaturated steroidal nuclei and vitexin and isovitexin. After that, it was evaluated the antioxidant potential by seven in vitro assay: Determination of Total Antioxidant Activity (CAT), DPPH, Reduction Power Test, Metal Ion Chelation, Copper Chelation, Superoxide Ion Sequestration Test, Hydroxyl Radical Sequestering Activity. These assays allowed us verify that the extracts presented antioxidant activity at extract concentrations: 100, 250 and 500 μg/mL. It was observed that the ethanoic, methanolic and aqueous extracts had activity in CAT, reducing power, sequestration of the hydroxyl radical. It was analyzed by Pearson's correlation if these results might be associated to the presence of phenolic compounds and sugars. It was also analyzed the antioxidant potential using in vivo models as C. elegans. This assay showed that the ethanoic extract increased its survival by approximately 30% in the presence of an oxidant stressor. Furthermore, the ethanoic extract was able to decrease the basal reactive species generated by the basal metabolism from C. elegans. Moreover, the wheat coleoptiles system showed that some extracts may have phytotoxic activity. The third in vivo model used in this work was cell culture. When it was used the 3T3 lineage it was observed that these extracts were not cytotoxic. However, it was not observed any antiproliferativa activity in tumor cell lineages. Concisely, the data obtained here showed that using n vitro and in vivo assays that these extracts in special ethanoic and aqueous had an interesting antioxidant potential.

MEMBROS DA BANCA:
Externo ao Programa - 2492944 - CAROLINE ADDISON CARVALHO XAVIER DE MEDEIROS
Interno - 1996107 - LIA REJANE MULLER BEVILAQUA
Presidente - 1251018 - RIVA DE PAULA OLIVEIRA