Evaluation of antimicrobial activity of silver nanoparticles for carboxymethylcellulose film applications in food packaging.

In this study, silver nanoparticles were prepared and incorporated into carboxymethylcellulose films to evaluate the antimicrobial activity for food packaging applications. The techniques carried out for material characterization were: infrared spectroscopy and thermal analysis for the silver nanoparticles and films, as well as particle size distribution for the nanoparticles and water vapor permeability for the films. The antimicrobial activity of silver nanoparticles prepared by casting method was investigated. The minimum inhibitory concentration (MIC) value of the silver nanoparticles to test Gram-positive (Enterococcus faecalis) and Gram-negative (Escherichia coli) microorganisms was carried out by the serial dilution technique, tested in triplicate to confirm the concentration used. The results were developed using the Mcfarland scale which indicates that the presence or absence of turbidity tube demonstrates the inhibition of bacteria in relation to the substance inoculated. It was found that the silver nanoparticles inhibited the growth of the tested microorganisms. The carboxymethylcellulose film embedded with silver nanoparticles showed the best antimicrobial effect against Gram-positive (E. faecalis) and Gram-negative (E. coli) bacteria (0.1 microg cm(-3)).

Controles físico, físico-químico, químico e microbiológico dos frutos de Dimorphandra mollis Benth., Fabaceae / Physic, physic-chemical, chemical and microbiological control of fruits of Dimorphandra mollis Benth., Fabaceae

Considerando-se a qualidade dos fitoterápicos, é importante salientar que a preocupação com esta questão inclui rigoroso acompanhamento das diferentes etapas de desenvolvimento e produção, desde a coleta do vegetal até o produto final. O controle de qualidade de drogas vegetais e seus extratos é essencial quando utilizados como matéria-prima para o desenvolvimento de fitoterápicos. Neste trabalho foram utilizadas diversas técnicas (farmacopeicas e não farmacopeicas) visando estabelecer parâmetros de qualidade dos frutos de Dimorphandra mollis Benth. (Leguminosae), popularmente conhecida como faveiro. Os resultados obtidos determinaram as características físico-químicas da droga vegetal e mostraram que o pó dos frutos e o extrato etanólico 70 por cento de D. mollis apresentam um teor de flavonóides de 10,25 por cento e 17,21 por cento, respectivamente. A análise fitoquímica preliminar dos frutos caracterizou a presença de taninos, saponinas e flavonóides. Na análise microbiológica do extrato não houve crescimento de patógenos entre os testes realizados.

Considering the quality of phytotherapic agents, it is important to point out that the concern with this subject includes rigorous attendance the different steps of development and production of these products, from the collection of the vegetable to the availability of the final product. The quality control for the plants and their extracts is essential when they are used in the development of phytotherapics. In this work, methodologies (pharmacopoeic and no pharmacopoeic) were employed to establish norms for the quality control of Dimorphandra mollis Benth. (Leguminosae) fruit, popularly known as faveira. Pharmacopoeic and no pharmacopoeic methodologies were employed to physic, physic-chemical, chemical and microbiological quality control. The results obtained established the physic-chemical characters of the drug and showed that the fruits and the ethanol 70 percent extract present a content of flavonoids of 10.25 percent and 17.21 percent, respectively. The preliminary phytochemical analysis of the D. mollis fruits evidenced tannins, saponnins and flavonoids. The microbiological analysis did not present pathogenic growth among the accomplished tests.