Navegando por Autor "Luccio, Marco Di"
Agora exibindo 1 - 2 de 2
- Resultados por página
- Opções de Ordenação
Artigo Liquefied petroleum gas as solvent medium for the treatment of immobilized inulinases(Wiley, 2013-02) Silva, Marceli Fernandes; Golunski, Simone Maria; Rigo, Diane; Mossi, Vinícius; Luccio, Marco Di; Mazutti, Marcio A.; Pergher, Sibele Berenice Castellã; Oliveira, Débora; Oliveira, J. Vladimir; Treichel, HelenBACKGROUND: The main goal of this work is to assess the influence of pressurized liquefied petroleum gas (LPG) treatment on the enzymatic activity of immobilized inulinases. The effects of process variables were evaluated through 23 experimental design. RESULTS: Inulinase from Klyveromyces marxianus NRRL Y‐7571 presented an increase of 163% in residual activity using LPG at 30 bar during 1 h exposure using a depressurization rate of 20 bar min−1. For Aspergillus niger commercial inulinase, an increment of 129% in residual activity was observed at 30 bar for 1 h treatment at the highest depressurization rate (20 bar min−1). Enzymatic activities changed significantly depending on the enzyme source and the experimental treatment conditions investigated, such as exposure time, depressurization rate and pressure. CONCLUSION: Hence, compressed LPG appears to be a promising technique with practical relevance as a preparation step to improve enzyme activity, thus helping the development of new biotransformation processes. © 2012 Society of Chemical IndustryArtigo Preparation and antimicrobial activity of polyethylene composite films with silver exchanged zeolite-Y(Elsevier, 2012-09-15) Boschetto, Daiane Lúcia; Lerin, Lindomar; Cansian, Rogério; Pergher, Sibele Berenice Castellã; Luccio, Marco DiThis study aimed at the preparation of antimicrobial films based on silver (Ag) exchanged zeolite Y. The zeolite was exchanged to a final concentration of 5% silver and was characterized by different methods. The inclusion of silver in the zeolite did not change its structure. The antimicrobial activity of the Ag-exchanged zeolite was assessed on Escherichia coli, by the minimum inhibitory concentration method (MIC). The zeolite with 5% Ag showed effective antimicrobial activity. The MIC was 0.5 mg zeolite/mL, which corresponds to 25 μg Ag/mL. The leaching of Ag ions to the medium was assessed by AAS, which showed that 56% of the silver ions was leached from the zeolite to the medium. The polyethylene films with the Ag–zeolite were prepared by the methods of wet-casting and thermal pressing of polyethylene beads mixed with Ag–zeolite, varying the zeolite content from 1 to 10 wt%. The inclusion of the Ag–zeolite in the film did not change the film thermal degradation. The films that showed antimicrobial activity on E. coli were those prepared with 5% zeolite containing 5% silver, showing the potential application of such films in food preservation and safety.