Banca de DEFESA: DIEGO ROBERTO DA CUNHA PASCOAL

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : DIEGO ROBERTO DA CUNHA PASCOAL
DATA : 03/12/2020
HORA: 10:00
LOCAL: videoconferência na plataforma RNP (sala PEI-UFBA)
TÍTULO:

IMPREGNATION / DEPOSITION OF COPAÍBA BIOACTIVES (Copaifera sp.) IN BIOPOLIMERIC DRESSINGS USING SUPERCRITICAL CO2 AND DICLOROMETAN IMMERSION.

PALAVRAS-CHAVES:

Impregnation/Deposition supercritical, immersion, terpenes, lupeol, β-caryophyllene, copaiba.

PÁGINAS: 143
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Produção
RESUMO:

The polymeric dressings are used in the treatment of chronic and acute wounds, especially those that are impregnated/deposited with bioactive compounds from medicinal plants to replace synthetic drugs, with less side effect to the patient. The impregnations/depositions of bioactive in polymeric matrices are carried out by different methods, which have in common the intensive use of organic solvents and an excessive number of process steps. On the other hand, the supercritical impregnation/deposition, carried out with carbon dioxide at high pressures, has some advantages such as speed in processing, the elimination of the use of organic solvents and the drying of the product at the end of the process. In this context, the present work aimed to study the technical feasibility of the impregnation/deposition processes of bioactive compounds from copaiba, in 2 biopolymeric commercial dressings: SpongostanTM and Promogran®. The supercritical impregnation/deposition method (SSI/SSD) with carbon dioxide and the classic method by immersion in organic solvent were used and compared. In the SSI/SSD method, the higher the pressure and density of the solvent , the greater the yield of oleoresin impregnated/deposited into biopolymer. It was observed that SpongostanTM underwent changes in the surface area, when processed at high pressures. The solubility of oleoresin in the supercritical solvent was the factor of greatest influence, for the process yield, related to the increase in system pressure. The terpenic compounds (bioactives of oleoresin) were detected in the two impregnated/deposited dressings. The classic impregnation/deposition method by immersion used the organic solvent dichloromethane, and in this method the leaf extract and oleoresin from copaiba were impregnated/deposited in the SpongostanTM dressing. The results of the impregnated/deposited bioactives were promising for both leaf extract and oleoresin in the biopolymer. The bioactive compounds of copaiba were identified in the impregnated/deposited dressings by nuclear magnetic resonance spectroscopy. Leaf extract and oleoresin showed antibacterial activities, obtaining inhibition of Gram-positive and Gram-negative bacterial growth. In both methods of impregnation/deposition, the porous structures of the dressings were preserved. In addition, it was observed in micrographs that the copaiba oleoresin had a homogeneous surface distribution in the different biopolymers regardless of the type of method. The results reveal that the solubility of the bioactive compounds of copaiba, in the different solvents used in the processes (supercritical carbon dioxide and dichloromethane) are fundamental for the success and technical viability of the impregnation/deposition of bioactive compounds into biopolymer matrices. The SSI/SSD method using supercritical CO2 showed advantages than immersion method using dichloromethane, because it allowed the control of the amounts of the impregnated/deposited bioactive, through fine adjustments in pressure and temperature, in addition to avoiding the presence of residual organic solvent in the biopolymer matrix.

MEMBROS DA BANCA:
Externo à Instituição - Ana Maria Antunes Dias
Externo à Instituição - Cássia Britto Detoni
Interno - 1677204 - ELAINE CHRISTINE DE MAGALHAES CABRAL ALBUQUERQUE
Externo à Instituição - Luis Padrela
Externo à Instituição - Ravenna Lessa Matos
Presidente - 1523793 - SILVIO ALEXANDRE BEISL VIEIRA DE MELO