Banca de QUALIFICAÇÃO: GIRLAINE SANTOS DA SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : GIRLAINE SANTOS DA SILVA
DATE: 05/06/2024
LOCAL: Programa de Pós-Graduação em Ciência de Materiais
TITLE:

Production of bacterial cellulose using extract Erythrina mulungu with antimicrobial Properties

KEY WORDS:

Bacterial Cellulose. Erythrina mulungu. Biopolymer. Medicinal plant.

PAGES: 84
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

Bacterial cellulose consists of a biopolymer that has unique and versatile characteristics, such as excellent mechanical properties, porosity, high crystallinity, moldability, high water retention capacity, thermochemical stability, among others. It also presents the possibility of modifications in its production process, and can be used for applications in different research segments. In the work under study, CB membranes were produced using both tea and the ethanolic extract of Erythrina Mulungu in the incorporation process. The work was divided into two stages, in the first, the production of CB was carried out using mulungu tea as a cultivation medium and a comparison was made with the salt medium. In the second stage, the mulungu ethanolic extract was incorporated into the CB in situ, ex situ and in the crushed membrane. Initially, the characterizations of the tea and the extract were carried out, observing the main functional groups present in the structures of these compounds in the FTIR analysis. In the analysis of antimicrobial activity, it was possible to observe that the bacteria E.coli and S.aureus were resistant in the presence of tea, while the same bacteria were sensitive to the ethanolic extract of mulungu, obtaining inhibition halos corresponding to 19.5 and 36 mm for E.coli and S.aureus bacteria, respectively. Regarding antioxidant activity, it was found that the mulungu ethanolic extract presented greater antioxidant activity than tea, obtaining a percentage inhibition value corresponding to 92.82% for the extract and 14.70% for tea. . In the first stage of the work, it was possible to produce CB using mulungu tea as a cultivation medium, obtaining a film with good formation and appearance, with a yield of 186.41 g/L for the hydrated membrane. In the FTIR analysis, the main functional groups of CB were observed, obtaining a spectrum similar to that of CB produced through salts. In the XRD analysis, it was observed that the CB produced by mulungu tea was less crystalline than the CB produced using salts, with a degree of crystallinity of 46% compared to 72% of the other. Regarding antimicrobial activity, the bacteria were highly sensitive to the membrane produced using mulungu tea, obtaining even greater inhibition halos than that of CB through salts. Regarding the second stage, it was possible to observe good formation for all samples and methods used. In the FTIR analysis, very similar spectra were found, with peaks that overlap the others, requiring another analysis to differentiate these compounds. In the XRD analysis, it was verified that the CB EX SITU and CB TRIT 25% samples presented greater crystallinity than the others, with crystallinity percentages corresponding to 83% and 94%, respectively. In terms of antimicrobial activity, the bacteria E.coli and S.aureus were highly sensitive to the membranes produced by the in situ and ex situ methods. Therefore, in this work it was possible to produce materials with excellent properties, with high antimicrobial and antioxidant potential, to be applied in medicinal or cosmetic areas.

COMMITTEE MEMBERS:
Presidente - 1356402 - CAROLINA LIPPARELLI MORELLI
Externa à Instituição - CRISTIANI VIEGAS BRANDAO GRISI - UFPB
Externa à Instituição - VIVIANE FONSECA CAETANO - UFPE