Detalhes bibliográficos
Ano de defesa: |
2019 |
Autor(a) principal: |
Iurckevicz, Genice
 |
Orientador(a): |
Cunha, Mário Antônio Alves da
 |
Banca de defesa: |
Não Informado pela instituição |
Tipo de documento: |
Tese
|
Tipo de acesso: |
Acesso aberto |
Idioma: |
por |
Instituição de defesa: |
Universidade Estadual do Centro-Oeste
|
Programa de Pós-Graduação: |
Programa de Pós-Graduação em Química (Doutorado)
|
Departamento: |
Unicentro::Departamento de Ciências Exatas e de Tecnologia
|
País: |
Brasil
|
Palavras-chave em Português: |
|
Palavras-chave em Inglês: |
|
Área do conhecimento CNPq: |
|
Link de acesso: |
http://tede.unicentro.br:8080/jspui/handle/jspui/1591
|
Resumo: |
B. dracunculifolia has been used in popular medicine because of its bioactive properties, which include anti-inflammatory, antiulcerative and hepatoprotective potentials. Similarly, β-glucans show different biological functionalities, such as immunomodulatory activity, anticarcinogenenic, hypoglycemic, among others. Nanoparticles containing Baccharis dracunculifolia extract and (16)-β-D-glucan (lasiodiplodan) were produced and characterized. In the present study, a multivariate approach using a central composite rotational design 2³ was used to define the best extraction conditions of the bioactive compounds from the leaves of Baccharis dracunculifolia, and an experimental design 2³ was used to define the production conditions of the nanoparticles by atomization in a spray dryer. Lasiodiplodan associated with maltodextrin and gum arabic were studied as matrices. The best extraction conditions of bioactive compounds from the leaves of B. dracunculifolia were 95 % methanol (v/v), 20 minutes extraction time at 70 °C. Under optimized conditions, high total phenolic content compounds (72.5 mg GAE/g) and high free radical scavenging activity DPPH (865.6 μmol TE/g) and ABTS (331.11 μmol TE/g) were obtained. In addition, a high ferric reducing power was observed (1558.00 μmol FeSO4.7H2O/g). The extract also showed antimicrobial activity, demonstrating fungicidal action against Candida tropicalis and C. albicans, and bacteriostatic effect against Escherichia coli, Salmonella enterica Typhimurium and Staphylococcus aureus. Analysis by HPLC-DAD revealed an extract rich in phenolic compounds, such as catechin, caffeic acid, p-coumaric acid, ferulic acid, pinocembrin and rutin. The nanoparticles obtained under optimized conditions (1.5 % lasiodiplodan, 5.0 % B. dracunculifolia extract and 10 % maltodextrin) had an average size varying from 230 to 1210 nm and high total phenolic content (3157.9 μg GAE/g). The mathematical model that best represented the release kinetics of the extract contained in the nanoparticles was the Korsmeyer-Peppas model. Diffusional exponent (n) values of 0.64 at pH 7.7 and 1.15 at pH 2.61 indicated particles with a non-Fickian or anomalous transport system and Super Case II transport, respectively. Thermal analysis showed that the particles exhibit high thermal stability (316 ºC) and X-ray diffraction analysis showed a characteristic diffractive profile of an amorphous structure. In the nanoparticles were found the phenolic compounds: caffeic acid; p-coumaric acid and catechin and comprise a new biomaterial with biological potential for applications in different areas. |