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Previous issue date: 2010-11-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The main aim of this study was to compare the procedure for dehydration of
Gracilaria birdiae prepared handmade and laboratory, collected in the northern coast
of Rio Grande do Norte. The sample was collected in the Rio do Fogo beach in
march 2009. The sample collected followed by two processing, the first the material
prepared in laboratory was air-dried at 50?C for 24 hours in air-flow oven. The
second the handmade sample was air-dried on the sun during three days. The
extract was prepared in three different solvents: ethanol, hydroethanol and water,
resulting in ethanol, hidroethanol and aqueous extracts from handmade and
laboratory sample. In according with results only the ethanol extract was fractionated
yielding the fractions hexane, dichloromethane and ethyl acetate fractions. The
different process to obtain Gracilaria birdiae resulted in the samples with different
shades. The soluble solids content was higher in the laboratory sample. The
chemical composition the both samples were characterized by presenting a
considerable amounts of carbohydrates, with amior percentage protein and ash,
respectively, in the handmade and laboratory sample. In two samples showed a low
content of lipids and the lipid profile showed a higher proportion of monounsaturated
fatty acids, with the absence polyunsaturated handmade sample. The phytochemical
screening by chemical reactions showed the presence of flavonoids, tannins,
alkaloids and saponins the laboratory sample, presenting a greater diversity of
bioactive compounds. Through of the analysis by thin layer chromatography was
possible to identify the phytosterols ?-sitosterol and stigmasterol the both samples,
also suggest the presence of ?-carotene and chlorophyll ? the laboratory sample.
The levels of total phenolics and flavonoids were more significant in the ethanol
extract of the laboratory sample. The in vitro lethality showed that extracts of the
laboratory sample and handmade from 125 to 500 ?g/ mL, respectively, were highly
lethal. In the evaluation of antioxidant capacity by the system ?-carotene/?cido
linoleic method and by DPPH radical scavernging assay, the ethanol extract from the
laboratory process showed significantly greater activity than the other extracts, being
and the first and second methods, respectively, lower and equivalent to the synthetic
antioxidant BHT. The handmade ethanol extract has not demonstrated skill in
deactivating free radicals, but showed activity in inhibiting lipid peroxidation, although
the values were significantly lower than the laboratory sample. We conclude that the
dehydration process in the laboratory is the most efficient technique to maintenance
of the chemical composition present in the seaweed, providing beneficial properties
such as antioxidant capacity. We emphasize that this property can be explored with
the objective of adding commercial value to the final product, which will promote the
expansion of production of this seaweed in the community of Rio do Fogo / O presente estudo tem como finalidade analisar de forma comparativa o
procedimento de desidrata??o de Gracilaria birdiae beneficiada laboratorialmente e
artesanalmente, cultivada no litoral norte do Rio Grande do Norte. A coleta das
amostras foi realizada na praia do Rio do Fogo em mar?o de 2009. Das amostras
coletadas seguiram-se dois processamentos, no primeiro o material coletado foi
mantido em estufa de ar circulante a 50?C, por 24 horas sendo obtida a amostra
laboratorial. No segundo a amostra artesanal foi desidrata??o ao sol por um per?odo
de tr?s dias. A extra??o consistiu em solu??es etan?lica, hidroetan?lica e aquosa,
resultando em extrato etan?lico, hidroetan?lico e aquoso. De acordo com os
resultados o extrato etan?lico foi fracionamento obtendo as fra??es hexano,
diclorometano e acetato de etila. As distintas formas de processamento da Gracilaria
birdiae promoveram a obten??o de amostras com tonalidades distintas. Quanto ao
teor de s?lidos sol?veis a amostra laboratorial apresentou superioridade. A
composi??o centesimal de ambas as amostras caracterizaram-se por apresentar um
consider?vel teor de carboidratos, com maior percentual de res?duo mineral e
prote?nas, respectivamente, na amostra laboratorial e artesanal. As duas amostras
apresentaram um baixo conte?do de lip?deos e um perfil lip?dico caracterizado por
uma maior propor??o de ?cidos graxos monoinsaturados, com aus?ncia de
poliinsaturados na amostra artesanal. A triagem fitoqu?mica evidenciou a presen?a
de flavon?ides, taninos, saponinas e alcal?ides na amostra laboratorial,
apresentando uma maior diversidade de compostos bioativos. Por meio da
cromatografia em camada delgada foi poss?vel identificar os fitoester?is ?-sitosterol e
stigmasterol em ambas as amostras, al?m de sugerir a presen?a do ?-caroteno e da
clorofila ? na amostra laboratorial. Os teores de compostos fen?licos totais e
caroten?ides totais foram mais expressivos no extrato etan?lico da amostra
laboratorial. A letalidade in vitro, demonstrou que os extratos etan?licos da amostra
laboratorial e artesanal a partir de 500 e 125 ?g/mL, respectivamente, foram
altamente letais. Na avalia??o da capacidade antioxidante pelo sistema ?-
caroteno/?cido linol?ico e pelo m?todo de sequestro do radical livre DPPH , o extrato
etan?lico proveniente do processo laboratorial apresentou atividade
significativamente maior que os demais extratos, sendo no primeiro e segundo
m?todo, respectivamente, inferior e equivalente ao antioxidante sint?tico BHT. O
extrato etan?lico proveniente do processo artesanal n?o demonstrou habilidade na
desativa??o de radicais livres, mas apresentou atividade na inibi??o da peroxida??o
lip?dica, por?m com valores significativamente inferiores a amostra laboratorial.
Conclui-se que o processo de desidrata??o em laborat?rio ? a t?cnica mais eficiente,
por supostamente promover a manuten??o dos compostos qu?micos presentes na
alga marinha, proporcionando propriedades ben?ficas como a capacidade
antioxidante. Ressalta-se que esta propriedade pode ser explorada com o intuito de
agregar valor comercial ao produto final, o que promover? a expans?o da produ??o
desta alga na comunidade do Rio do Fogo / 2020-01-01
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/13465 |
| Date | 26 November 2010 |
| Creators | Paiva, Mirely de Freitas |
| Contributors | CPF:20054548420, http://lattes.cnpq.br/0321740024191482, Randau, Karina Perrelli, CPF:76704556400, http://lattes.cnpq.br/5089595850981385, Moura, T?lio Fl?vio Accioly Lima e, CPF:13138863434, http://lattes.cnpq.br/4452581275123481, 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/embargoedAccess |
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