Banca de QUALIFICAÇÃO: LUIS OTAVIO DE ARAUJO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : LUIS OTAVIO DE ARAUJO
DATA : 17/06/2019
HORA: 14:00
LOCAL: A definir
TÍTULO:

ACTIVE PACKAGING: SYNTHESIS OF ANTIMICROBIAL FILMS BASED ON LOW DENSITY POLYETHYLENE AND A ZEOLITE CONTAINING SILVER

PALAVRAS-CHAVES:

Active packagings. Zeolite. Silver. Polymer film. Antimicrobial packaging

PÁGINAS: 51
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Inorgânica
ESPECIALIDADE: Físico Química Inorgânica
RESUMO:

Active antimicrobial packagings are materials endowed with the ability to inhibit and eliminate microorganisms that deteriorate food. Considering the great importance of practices aimed at obtaining safer food, less waste and longer shelf life of these products, the present work had the objective of synthesizing low density Polyethylene and zeolite A composite films substituted with different contents of silver for use as active packaging. 1%, 5% and 10% silver were inserted by means of cation exchange in the structure of zeolite A. The starting materials were characterized by different techniques. The silver insertion in the zeolite did not change its structure. The antibacterial activity of the silver-substituted zeolite was performed by the minimum inhibitory concentration using Escherichia coli as target bacterium. The MIC of the zeolite with 1% silver and concentration of 0,05 mg zeolite/mL was not able to inhibit the visible growth of the bacterium, however, with the increase of the concentration there was total inhibition in the period of 24h. The contents of 5% and 10% showed MIC equal to 0,05 mg of zeolite/mL. The LDPE films added with silver-substituted zeolite A were synthesized by wet-casting. The zeolite mass content in the films ranged from 1% to 5% by mass. The films containing higher zeolite/Ag mass content started the degradation at lower temperatures. The films with best antibacterial activity against Escherichia coli and Staphylococcus aureus were those prepared with 5% and 10% silver substituted zeolite and with a mass content of 5% (w/w), showing great potencial for applications such as active packaging in food preservation.

MEMBROS DA BANCA:
Interna - 349770 - DULCE MARIA DE ARAUJO MELO
Externa ao Programa - 1760065 - KATYA ANAYA JACINTO
Externa à Instituição - LINDIANE BIESEKI - UFRN
Presidente - 1308577 - SIBELE BERENICE CASTELLA PERGHER