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1.
Int J Biol Macromol ; 275(Pt 1): 133386, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38914407

RESUMO

Biodegradable starch foam trays offer an eco-friendly substitute for petroleum-based single-use packaging, notably polystyrene foams. However, they lack flexibility, tensile strength, and water-sensitivity, addressable through lignocellulosic reinforcement. This study aimed to develop biodegradable starch foam trays filled with different food-chain side streams for sustainable alternative packaging. Corncob, soybean straw, cassava peel, araucaria seed hull, yerba mate stalks and yerba mate leaves petiole were collected, dried and ground to <250 µm. The trays were filled with 13 % (w/w) of each food-chain side streams and produced by hot molding. The trays morphology, moisture, water activity (aw), thickness, bulk density, tensile strength, elongation at break, Young's modulus, bending strength, maximum deflection, and sorption isotherms were investigated. Reinforcements slightly increased the foams bulk density, reduced the tensile strength and maximum deflection and while bending strength increased from 0.20 MPa to 1.17-1.80 MPa. The elasticity modulus decreased by adding any filling, that resulted in ductility improvement; however, these packaging have moisture-sensitive material especially for aw higher than 0.52, which drives the use recommendation for dry products storage or shipping/transport. The biodegradable starch foam trays filled with side streams were successfully produced and offer excellent alternative to petroleum-based packaging low-density material with bending strength improved.


Assuntos
Amido , Resistência à Tração , Amido/química , Água/química , Embalagem de Alimentos/métodos , Manihot/química
2.
Appl Biochem Biotechnol ; 149(3): 195-203, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18500581

RESUMO

Production of inulinase by solid state fermentation always involves an extraction step, which dictates enzyme recovery yield and is related to cultivation conditions and control of process parameters. This work is focused on the study of extraction conditions aiming to maximize yield of an inulinase obtained by solid state fermentation of sugar cane bagasse and Kluyveromyces marxianus NRRL Y-7571. Kinetics of extraction was followed varying the kind of solvent used. After determining the best solvent, an experimental design was carried out to study the effect of the solid/liquid ratio (1:10-1:20), extraction temperature (20-53 degrees C), and stirring rate (50-177 rpm). Results showed that maximum yield was obtained when sodium acetate buffer 0.1 M pH 4.8 was used, using a solid/liquid ratio of 1:10, at 53 degrees C and 150 rpm for 40 min.


Assuntos
Fermentação , Glicosídeo Hidrolases/isolamento & purificação , Kluyveromyces/metabolismo , Saccharum/metabolismo , Cinética , Concentração Osmolar
3.
Appl Biochem Biotechnol ; 121-124: 231-41, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15917602

RESUMO

This work investigated the production of fatty acid ethyl esters (FAEEs) from soybean oil using n-hexane as solvent and two commercial lipases as catalysts, Novozym 435 and Lipozyme IM. A Taguchi experimental design was adopted considering the variables temperature (35-65 degrees C), addition of water (0-10 wt/wt%), enzyme (5-20 wt/wt%) concentration, and oil-to-ethanol molar ratio (1:3-1:10). It is shown that complete conversion in FAEE is achieved for some experimental conditions. The effects of process variables on reaction conversion and kinetics of the enzymatic reactions are presented for all experimental conditions investigated in the factorial design.


Assuntos
Álcoois/química , Ácidos Graxos/síntese química , Hexanos/química , Lipase/química , Solventes/química , Óleo de Soja/química , Ativação Enzimática , Enzimas Imobilizadas/química , Ésteres , Proteínas Fúngicas , Hidrólise , Cinética , Soluções
4.
Appl Biochem Biotechnol ; 121-124: 553-60, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15920262

RESUMO

This article reports experimental data on the production of fatty acid ethyl esters from refined and degummed soybean oil and castor oil using NaOH as catalyst. The variables investigated were temperature (30-70 degrees C), reaction time (1-3 h), catalyst concentration (0.5-1.5 w/wt%), and oil-to-ethanol molar ratio (1:3-1:9). The effects of process variables on the reaction conversion as well as the optimum experimental conditions are presented. The results show that conversions >95% were achieved for all systems investigated. In general, an increase in reaction temperature, reaction time, and in oil-to-ethanol molar ratio led to an enhancement in reaction conversion, whereas an opposite trend was verified with respect to catalyst concentration.


Assuntos
Óleo de Rícino/química , Etanol/química , Ácidos Graxos/síntese química , Hidróxido de Sódio/química , Óleo de Soja/química , Álcalis/química , Catálise , Técnicas de Química Combinatória , Esterificação , Ésteres , Gasolina , Concentração de Íons de Hidrogênio , Temperatura
5.
Appl Biochem Biotechnol ; 113-116: 771-80, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15054231

RESUMO

We studied the production of fatty acid ethyl esters from castor oil using n-hexane as solvent and two commercial lipases, Novozym 435 and Lipozyme IM, as catalysts. For this purpose, a Taguchi experimental design was adopted considering the following variables: temperature (35-65 degrees C), water (0-10 wt/wt%), and enzyme (5-20 wt/wt%) concentrations and oil-to-ethanol molar ratio (1:3 to 1:10). An empirical model was then built so as to assess the main and cross-variable effects on the reaction conversion and also to maximize biodiesel production for each enzyme. For the system containing Novozym 435 as catalyst the maximum conversion obtained was 81.4% at 65 degrees C, enzyme concentration of 20 wt/wt%, water concentration of 0 wt/wt%, and oil-to-ethanol molar ratio of 1:10. When the catalyst was Lipozyme IM, a conversion as high as 98% was obtained at 65 degrees C, enzyme concentration of 20 wt/wt%, water concentration of 0 wt/wt%, and oil-to-ethanol molar ratio of 1:3.


Assuntos
Biotecnologia/métodos , Óleo de Rícino/química , Química Orgânica/métodos , Álcoois/química , Catálise , Ésteres/química , Etanol , Cinética , Lipase/química , Modelos Estatísticos , Óleos de Plantas , Solventes , Temperatura , Fatores de Tempo
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