Análise da composição de hemiceluloses de cana de açúcar extraídos com dimetil sulfóxido (DMSO) e hidróxido de sódio (NaOH)
Data
2020-08-13
Autores
Gonzalez, Lorenzo Lang 
Orientadores
Corete, Aline Andreia Cavalari
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
As aplicações biotecnológicas do bagaço de cana como a geração de etanol, por
exemplo, estão diretamente ligadas à compreensão da estrutura da parede
celular da cana. Apesar da importância da planta para toda a cadeia produtiva,
diversos aspectos da estrutura da parede celular da cana ainda não foram
esclarecidos, em especial o padrão de ramificação com acetato e ácido ferúlico
na principal hemicelulose da parede de cana: o arabinoxilano. Em grande parte, o
problema se deve ao protocolo típico de extração de polissacarídeos que fraciona
a parede com NaOH que devido ao elevado pH altera a estrutura nativa do
polissacarídeo. Para estudar a estrutura nativa das hemiceluloses é preciso
desenvolver protocolos de extração que evitem pH’s extremos, sendo esse o
objetivo deste projeto propor o desenvolvimento de uma técnica de extração de
hemicelulose baseada em dimetil sulfóxido (DMSO) mantendo ao máximo a
estrutura nativa dos polímeros. A partir do material extraído por técnicas
tradicionais (fracionamento com NaOH) e extração com DMSO serão feitas
análises quantitativas (rendimento), qualitativas por meio da análise de
monossacarídeos, além de uma avaliação de qual a melhor técnica de extração
para análise de arabinoxilano de cana de açúcar. Foi observado que a
purificação com resina Amberlite XAD-2 foi bastante eficiente para a separação
dos oligossacarídeos, na análise por HPLC foi possível observar a presença de
compostos fenólicos no material extraído, sugerindo uma presença de ácido
ferúlico no material extraído com DMSO.
The biotechnological applications of sugarcane bagasse such as ethanol generation are directly linked to the understanding of the structure of the sugarcane cell wall. Despite the importance of this plant for the entire production chain, several aspects of the structure of the sugarcane cell wall have not yet been clarified, especially the branching pattern with acetate and ferulic acid in the main hemicellulose of the cane wall: arabinoxylan. The problem is largely due to the typical polysaccharide extraction protocol that fractionates the wall with NaOH, and due to the high pH, it alters the polysaccharide's native structure. Therefore, to study the native structure of hemicelluloses, it is necessary to develop extraction protocols that avoid extreme pH's. Thus, the objective of this project is to propose the development of a hemicellulose extraction technique based on dimethyl sulfoxide (DMSO) while maintaining the native structure of the polymers to the maximum. From the material extracted by traditional techniques (fractionation with NaOH) and extraction with DMSO, quantitative analyzes based on yield will be made, qualitative through the analysis of monosaccharides, in addition to an evaluation of which is the best extraction technique for analysis of arabinoxylan of sugar cane. It was observed that purification with Amberlite XAD2 resin was quite efficient for the separation of oligosaccharides, in the HPLC analysis we observed the presence of phenolic compounds in the extracted material, suggesting a presence of ferulic acid in the material extracted with DMSO.
The biotechnological applications of sugarcane bagasse such as ethanol generation are directly linked to the understanding of the structure of the sugarcane cell wall. Despite the importance of this plant for the entire production chain, several aspects of the structure of the sugarcane cell wall have not yet been clarified, especially the branching pattern with acetate and ferulic acid in the main hemicellulose of the cane wall: arabinoxylan. The problem is largely due to the typical polysaccharide extraction protocol that fractionates the wall with NaOH, and due to the high pH, it alters the polysaccharide's native structure. Therefore, to study the native structure of hemicelluloses, it is necessary to develop extraction protocols that avoid extreme pH's. Thus, the objective of this project is to propose the development of a hemicellulose extraction technique based on dimethyl sulfoxide (DMSO) while maintaining the native structure of the polymers to the maximum. From the material extracted by traditional techniques (fractionation with NaOH) and extraction with DMSO, quantitative analyzes based on yield will be made, qualitative through the analysis of monosaccharides, in addition to an evaluation of which is the best extraction technique for analysis of arabinoxylan of sugar cane. It was observed that purification with Amberlite XAD2 resin was quite efficient for the separation of oligosaccharides, in the HPLC analysis we observed the presence of phenolic compounds in the extracted material, suggesting a presence of ferulic acid in the material extracted with DMSO.