Existe um grande interesse mundial pelo desenvolvimento de novas tecnologias que possibilitem o u... more Existe um grande interesse mundial pelo desenvolvimento de novas tecnologias que possibilitem o uso de produtos com menor impacto ambiental. Este artigo apresenta um estudo do reaproveitamento de materiais gerados pelas agroindústrias. O bagaço da cana-de-açúcar vem sendo ...
Sugarcane bagasse with and without acid hydrolysis was used for extraction of cellulose. The baga... more Sugarcane bagasse with and without acid hydrolysis was used for extraction of cellulose. The bagasse pulps without or with hydrolysis, and commercial mixtures of these materials in different proportions were used for the production of textile fibers. All sugarcane bagasse pulps were obtained by the alkaline pulping soda-anthraquinone (AQ) and subjected to chemical bleaching to remove residual lignin using hydrogen peroxide or sodium chloride. Pulps were used to obtain fibers with N-methylmorpholine-N-oxide (NMMO). Bagasse and pulps were characterized by their chemical composition. Fibers were analyzed to evaluate maximum water uptake loading or swelling, weight loss and mechanical properties. Microstructure was analyzed by scanning electron microscope (SEM). The pulping yield was 34.6% for bagasse without hydrolysis and 26.6% for bagasse with hydrolysis. The fibers showed water uptake capacity in the range of 60-86%. Fibers obtained from commercial cellulose and bagasse without hydr...
International Journal of Biological Macromolecules, 2021
Chitosan microspheres (CMS) by the emulsion-chemical cross-linking method with and without lysozy... more Chitosan microspheres (CMS) by the emulsion-chemical cross-linking method with and without lysozyme immobilization were synthesized and characterized. The technique conditions were adjusted, and spherical particles with approximate diameters of 3.74 ± 1.08 μm and 0. 29 ± 0.029 μm to CMS and chitosan-lysozyme microspheres (C-LMS), respectively, were obtained. The microspheres were characterized by scanning electron microscopy (FESEM), Spectroscopy Fourier Transform Spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and zeta potential. Particle size was identified by laser light scattering (DLS) and the thermal properties by Differential Scanning Calorimetry (DSC) and Thermogravimetry (TGA) were determined. By the lysis of Micrococcus lysodeikticus, the activity of the microspheres was determined, and the results correlated with the amount of lysozyme used in the immobilization process and the enzyme loading efficiency was 67%. Finally, release tests pointed out the amount of enzyme immobilized on the microsphere surface. These results showed that chitosan microspheres could be used as material for lysozyme immobilization by cross-linking technique. The antimicrobial activity was tested by inhibition percent determination, and it evidenced both chitosan microspheres (CMS) and chitosan-lysozyme microspheres (C-LMS) positive antimicrobial activity to Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa.
This chapter describes the different ways of performing sugarcane straw exploitation. This is an ... more This chapter describes the different ways of performing sugarcane straw exploitation. This is an important agro-residue in Brazil that has a wide range of feasible applications. For these specific usages, it is essential to have an effective knowledge on the sugarcane straw fiber related to its chemical composition (lignin and carbohydrate contents) and on cellulose extraction processes. We address the recent studies on biological processes, such as alternative pretreatment in combination with chemical processes and bleaching methods for residual lignin removal. This chapter also addresses some recent examples on the production of ethanol, bio-oil, enzymes, composites, and pulps from sugarcane straw. In addition, we discuss the development of lyocell textile fibers. The scientific and technological advances in the exploitation of sugarcane straw have a strong appeal, and the use of an agro-residue in this application is an important issue.
Existe um grande interesse mundial pelo desenvolvimento de novas tecnologias que possibilitem o u... more Existe um grande interesse mundial pelo desenvolvimento de novas tecnologias que possibilitem o uso de produtos com menor impacto ambiental. Este artigo apresenta um estudo do reaproveitamento de materiais gerados pelas agroindústrias. O bagaço da cana-de-açúcar vem sendo ...
Sugarcane bagasse with and without acid hydrolysis was used for extraction of cellulose. The baga... more Sugarcane bagasse with and without acid hydrolysis was used for extraction of cellulose. The bagasse pulps without or with hydrolysis, and commercial mixtures of these materials in different proportions were used for the production of textile fibers. All sugarcane bagasse pulps were obtained by the alkaline pulping soda-anthraquinone (AQ) and subjected to chemical bleaching to remove residual lignin using hydrogen peroxide or sodium chloride. Pulps were used to obtain fibers with N-methylmorpholine-N-oxide (NMMO). Bagasse and pulps were characterized by their chemical composition. Fibers were analyzed to evaluate maximum water uptake loading or swelling, weight loss and mechanical properties. Microstructure was analyzed by scanning electron microscope (SEM). The pulping yield was 34.6% for bagasse without hydrolysis and 26.6% for bagasse with hydrolysis. The fibers showed water uptake capacity in the range of 60-86%. Fibers obtained from commercial cellulose and bagasse without hydr...
International Journal of Biological Macromolecules, 2021
Chitosan microspheres (CMS) by the emulsion-chemical cross-linking method with and without lysozy... more Chitosan microspheres (CMS) by the emulsion-chemical cross-linking method with and without lysozyme immobilization were synthesized and characterized. The technique conditions were adjusted, and spherical particles with approximate diameters of 3.74 ± 1.08 μm and 0. 29 ± 0.029 μm to CMS and chitosan-lysozyme microspheres (C-LMS), respectively, were obtained. The microspheres were characterized by scanning electron microscopy (FESEM), Spectroscopy Fourier Transform Spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and zeta potential. Particle size was identified by laser light scattering (DLS) and the thermal properties by Differential Scanning Calorimetry (DSC) and Thermogravimetry (TGA) were determined. By the lysis of Micrococcus lysodeikticus, the activity of the microspheres was determined, and the results correlated with the amount of lysozyme used in the immobilization process and the enzyme loading efficiency was 67%. Finally, release tests pointed out the amount of enzyme immobilized on the microsphere surface. These results showed that chitosan microspheres could be used as material for lysozyme immobilization by cross-linking technique. The antimicrobial activity was tested by inhibition percent determination, and it evidenced both chitosan microspheres (CMS) and chitosan-lysozyme microspheres (C-LMS) positive antimicrobial activity to Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa.
This chapter describes the different ways of performing sugarcane straw exploitation. This is an ... more This chapter describes the different ways of performing sugarcane straw exploitation. This is an important agro-residue in Brazil that has a wide range of feasible applications. For these specific usages, it is essential to have an effective knowledge on the sugarcane straw fiber related to its chemical composition (lignin and carbohydrate contents) and on cellulose extraction processes. We address the recent studies on biological processes, such as alternative pretreatment in combination with chemical processes and bleaching methods for residual lignin removal. This chapter also addresses some recent examples on the production of ethanol, bio-oil, enzymes, composites, and pulps from sugarcane straw. In addition, we discuss the development of lyocell textile fibers. The scientific and technological advances in the exploitation of sugarcane straw have a strong appeal, and the use of an agro-residue in this application is an important issue.
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