ABSTRACT
Methylcellulose is a biopolymer, which can be used in the preparation of films for the production of biodegradable active packaging. In this work, the methylcellulose films containing biosynthesized silver nanoparticles (AgNPs) were developed using Lippia alba extract. The physico-chemical, antioxidant, and antimicrobial properties of the films were studied. The insertion of Lippia alba compounds was verified using infrared spectroscopy (FTIR), with the appearance of a band at 1595â¯cm-1 and 1410â¯cm-1 which is characteristic of CCC stretches of the aromatic ring, and the increase in the hydrophobicity of the films containing the extract in relation to the control film. The films containing AgNPs presented a decrease in tensile strength and elastic modulus, but increased elongation. It was observed that the films that contain AgNPs presented superior antioxidant activity compared to the other films, besides antimicrobial activity against the tested microorganisms.
Subject(s)
Anti-Infective Agents/chemistry , Antioxidants/chemistry , Lippia/chemistry , Metal Nanoparticles/chemistry , Methylcellulose/chemistry , Plant Extracts/chemistry , Silver/chemistry , Mechanical Phenomena , Microbial Sensitivity TestsABSTRACT
O ácido hialurônico (AH) é uma macromolécula com importância na área médica, na área farmacêutica e na indústria de cosméticos. O cordão umbilical e a crista de galo são os tecidos mais ricos neste polissacarídeo. O Brasil é um dos principais exportadores de frango do mundo; assim, o aproveitamento das cristas dos animais abatidos para a obtenção de AH se mostra particularmente atraente. Este trabalho teve como objetivos fazer a extração do AH da crista de frango e determinar a atividade antioxidante in vitro. Cristas de frangos secas e delipidadas foram submetidas à digestão proteolítica e posteriormente à precipitação com cloreto de cetilpiridinio (CPC). A atividade antioxidante foi determinada pelo método de seqüestro do radical 2,2 - difenil 1-picrilhidrazil (DPPH). A concentração de glicosaminoglicanos (GAGs) na crista de frango é de 14,9µg de ácido hexurônico /mg de tecido seco e o AH extraído apresentou ótima atividade antioxidante in vitro. Desse modo, o AH pode ser aproveitado como um resíduo das indústrias de processamento de frangos.
The hyaluronic acid (HA) is an important macromolecule in medical and pharmaceutical areas as well as in the cosmetics industry. The umbilical cord and the chicken crest are two of the richest tissues in this polysaccharide. Since Brazil is one of the main chicken exporters in the world, the utilization of crests from slaughtered animals to obtain HA is particularly attractive. The present research aimed to extract hyaluronic acid (HA) from the crest and determine its antioxidant activity in vitro. Dry and delipidated chicken crest underwent proteolytic digestion and subsequent precipitation with cetylpyridinium chloride (CPC). Antioxidant activity was determined by the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method. The glycosaminoglycans (GAG) concentration in the chicken crest was 14.9µg of hexuronic acid /mg of dry tissue and the extracted HA presented great antioxidant activity in vitro. Thus, HA may be used as a sub-product of poultry processing industries.
