Banca de DEFESA: LUCIANA FENTANES MOURA DE MELO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : LUCIANA FENTANES MOURA DE MELO
DATA : 08/03/2018
HORA: 14:00
LOCAL: Sala Carl Peter von Dietrich - Departamento de Bioquímica
TÍTULO:

Coccoloba alnifolia Casar extracts and its biological activities 

PALAVRAS-CHAVES:

antioxidante potential, cell lineages, C. elegans, wheat coleoptile

PÁGINAS: 76
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
SUBÁREA: Química de Macromoléculas
RESUMO:

The use of medicinal plants has been a common practice in folk medicine. This knowledge has been based on the experience that it has been passed though many generations. However, many times this knowledge do not have any scientific base. The molecules responsive for these activities are the secondary metabolic produce as 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 its potential to identify new biomolecules. In order to do this, six extracts (HE, CE, EE, ME, WEE e WE) 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 Capacity (TAC), DPPH, Redution Power test, Metal Ion Chelation, Copper Chelation, Superoxide Ion Scavenging test and Hydroxyl Radical Scavenging Activity. These assays allowed us verify that the extracts presented antioxidant activity at extract concentrations: 100, 250 and 500 µg/mL. It was observed the ethanolic, methanolic and aqueous extracts had activity in TAC, reducing power, scavenging of the hydroxyl radical. The Pearson´s correlation showed that these results may be associated to the presence of phenolic compounds and sugars. It was also evaluated the antioxidant potential using in vivo models as Caenorhabditis elegans. This assay showed that the ethanolic extract increased its survival by approximately 30% in the presence of an oxidant stressor. Furthermore, the ethanolic 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 antiproliferative activity in tumor cell lineages. In sumary, the data obtained here showed that using in vitro and in vivo assays that these extracts in special ethanolic and aqueous had an interesting antioxidant potential and it will be important to go further in this research.

MEMBROS DA BANCA:
Presidente - 1453487 - KATIA CASTANHO SCORTECCI
Externo à Instituição - DEBORAH YARA ALVES CURSINO DOS SANTOS - USP
Externo à Instituição - JAILMA ALMEIDA DE LIMA - CRI