O foco deste estudo correspondeu a hidrólise enzimática da polpa celulósica de sisal previamente mercerizada (20g de polpa.L^-1, solução aquosa de NaOH 20%) via agitação mecânica (50°C,3h, M-AgMec-50°) e ultrassom (25°C,1h) a 20% (M-US-20%) e 40% (M-US-40%) de amplitude. As polpas mercerizadas apresentaram as seguinte propriedades: M-AgMec-50° 97,4% de α-celulose, cristalinidade (Ic) de 68% e massa molar média viscosimétrica (MMvis) de 94618,0g.mol^-1, M-US-20% 95% de α-celulose, Ic de 68% e MMvis de 87581,6g.mol^-1, M-US-40% 91,2% de α-celulose, Ic de 66% e MMvis de 81786,9g.mol^-1. As reações de hidrólise (48h) foram realizadas utilizando enzimas celulase comercial (Accellerase 1500) e enzimas obtidas a partir do crescimento do fungo Aspergillus sp. Alíquotas constituídas por polpas não reagidas e licor foram retiradas do meio durante a reação. As polpas não reagidas foram caracterizadas em relação a Ic, MMvis, comprimento e espessura e microscopia eletrônica de varredura (MEV). Os licores foram avaliados pelo método Miller (DNS) e cromatografia líquida de alta eficiência(CLAE). Na hidrólise da polpa celulósica de sisal M-AgMec-50°, variou-se a quantidade de enzimas utilizadas (0,5 (HE-SAG-0,5); 0,7 (HE-SAG-0,7) e 0,9 (HE-SAG-0,9) mL de complexo enzimático. g^-1 polpa celulósica). O maior rendimento de glicose (98%), obtido via CLAE, correspondeu a HE-SAG-0,9, sendo esta proporção de enzimas utilizada para as reações usando as polpas M-US-20% (HE-SU20-0,9), M-US-40%(HE-SU40-0,9). Dentre todas as polpas consideradas, o melhor rendimento de glicose foi para HE-SAG-0,9 pois, a presença de maior quantidade de hemiceluloses nas polpas celulósicas tratadas via ultrassom (HE-SU20-0,9 HE-SU40-0,9) prejudicou o acesso das enzimas às cadeias de celulose. As análises das polpas não reagidas mostraram que as enzimas celulases no geral agiram primeiramente na região não cristalina. Comportamentos variados foram observados com relação a Ic e MMvis, dependendo do intervalo de tempo transcorrido durante a reação. Considerando o pico de maior densidade de comprimento para as fibras de HE-SAG-0,5; HE-SAG-0,7 e HE-SAG-0,9, a variação durante a reação foi de [129-215] μm para [77-129] μm. As fibras de comprimentos superiores a [359-599] μm passaram a ser menores, aumentando a concentração de fibras com comprimentos menor que 359μm no meio. Para HE-SAG-0,5; HE-SAG-0,7; HE-SAG-0,9 o pico de maior densidade para a espessura variou de [28-39] para [11-23] μm, e para HE-SU20-0,9 e HE-SU40-0,9 este variou de [18-30] μm para [14-18] μm. O conjunto de resultados indicou que as enzimas agiram principalmente a partir das superfícies das fibras. As reações utilizando as enzimas celulases comercial e obtidas a partir do fungo Aspergillus foram realizadas utilizando outros substratos, além de M-AgMec-50° (HE-SAG-0,5; H-Aspergillus-SAG-1,5), ou seja, celulose microcristalina (HE-MICRO-0,5; H-Aspergillus-MICRO-1,5) e papel filtro (HE-PFT-0,5; H-Aspergillus-PFT-1,5). Dos três substratos utilizados, o papel filtro apresentou maior quantidade de hemiceluloses, e por isto, para as duas enzimas, observou-se para esta amostra o maior teor de açúcar redutor (DNS). A enzima fúngica, para todos os substratos, produziu um teor de açúcar muito menor que o obtido usando enzima comercial. As enzimas foram avaliadas via eletroforese de proteínas, sendo que para as enzimas fúngicas, foram observadas bandas de endoglucanases e exoglucanases, confirmando que durante o crescimento do fungo houve a formação das enzimas celulases. No entanto, as respectivas bandas das celulases comerciais mostraram que estas enzimas estão presentes em concentração consideravelmente maior, comparativamente as obtidas a partir do fungo Aspergillus sp. Ao comparar os resultados de Ic, MMvis, comprimento e espessura para todas as polpas não reagidas, usando as enzimas comercial e fúngica, observou-se que as enzimas fúngicas, nas condições consideradas no presente estudo atuaram de forma significativamente menos intensa que a comercial. Os estudos envolvendo as enzimas fúngicas requisitam aprofundamento. Dentre os resultados obtidos, destaca-se a alta conversão a glicose da polpa celulósica M-AgMec-50°, o que indicou que a hidrólise enzimática de polpa celulósica de sisal, com características similares à esta, apresenta grande potencial para produção de açúcares via catálise enzimática, visando obtenção de etanol.

This study corresponds to the enzymatic hydrolysis of previously mercerized pulp sisal (20g polpa.L^-1 aqueous 20% NaOH) via mechanical agitation (50° C, 3h, M-AgMec-50°) and ultrasound (25° C, 1h) at 20% (M-US-20%) and 40% (-M-US 40%) of amplitude. The mercerized pulp had the following properties: M-AgMec-50° 97.4% of α-cellulose, 68% of crystallinity (Ic) and average viscometric molecular weight (MMvis) of 94618,0g.mol^-1, M-US-20% 95% of α-cellulose, 68% of Ic and MMvis of 87581,6 g.mol^-1, M-US-40% 91.2% α-cellulose, 66% of Ic and 81786,9g .mol^-1 of MMvis. The hydrolysis reactions (48 h) were performed using commercial enzymes cellulase (Accellerase 1500) and enzymes obtained from the growth of the fungus Aspergillus sp. Aliquots constituted of unreacted pulp and liquor were taken from the medium during the reaction. The unreacted pulps were characterized with respect to Ic, MMvis, length and thickness and scanning electron microscopy (SEM). The liquors were analyzed by high performance liquid chromatography (HPLC) and by the Miller method (DNS). In the hydrolysis of the cellulose pulp sisal M-AgMec -50°, the amount of enzymes used was varied (0.5 (HE- SAG-0.5), 0.7 (HE-SAG-0.7) and 0.9 (HE-SAG-0.9) mL enzyme complex.g^-1 pulp). The highest yield of glucose (98%), obtained via HPLC, corresponded to HE-SAG-0.9. This proportion of enzymes was used for the reactions using the pulps M-US-20% (HE-SU20-0,9) and M-US-40% (HE-SU40-0,9). Among all the considered pulps, the best performance for glucose was HE-SAG-0.9 as the presence of greater amounts of hemicellulose in pulps treated via ultrasonic (HE-HE-SU 20-0,9 SU40-0,9 ) made it difficult for the enzymes to access the cellulose chains. The analysis of unreacted pulps showed that, in general, cellulase enzymes act primarily on the non-crystalline region. Different behaviors were observed with respect to Ic and MMvis, depending on the time interval elapsed during the reaction. Considering the peak density of greater length for the fibers HE-SAG-0.5; HE-SAG-0.7 and HE-SAG-0.9, the variation during the reaction was [129-215] μm for [77-129] μm. The fibers of lengths greater than [359-599] μm became smaller, thus increasing the concentration of fibers with lengths smaller than 359μm in the medium. For HE-SAG-0.5; HE-SAG-0.7; HE-SAG-0.9 the peak of greater density of thickness varied from [28-39] to [11-23] μm and, for HE-SU20-0,9 and HE-SU40-0,9 that varied from [18-30] μm to [14-18] μm. The set of results indicated that the enzymes acted primarily from the fiber surfaces. Reactions using commercial cellulases and enzymes obtained from Aspergillus sp fungus were performed using other substrates in addition to M-AgMec-50°(HE-SAG-0,5; H-Aspergillus-SAG-1,5), which were microcrystalline cellulose (HE-MICRO-0,5; H-Aspergillus-MICRO-1,5) and filter paper (HE-PFT-0.5, H-Aspergillus-PFT-1,5). Out of the three substrates used, the filter paper showed a higher amount of hemicellulose, and therefore the highest concentration of reducing sugars (DNS) was observed in this sample for the two enzymes. For all the substrates, the fungal enzyme produced a much lower level of sugar than that obtained by using commercial enzyme. The enzymes were evaluated by electrophoresis of proteins. The bands of endoglucanases and exoglucanases were observed in the fungal enzymes, confirming that during the growth of the fungus there was the formation of cellulase enzymes. However, the respective bands of commercial cellulases showed that these enzymes are present in considerably higher concentration when compared to those obtained from the fungus Aspergillus sp. When comparing the results of Ic, MMvis, length and thickness for all the unreacted pulps using commercial and fungal enzymes under the conditions considered in this study, it was observed that fungal enzymes acted significantly less intensely than the commercial ones. Studies involving fungal enzymes need deepening. Among the obtained results, there is a high conversion of the glucose pulp AgMec-M50°, which indicated that the enzymatic hydrolysis of cellulosic pulps with features similar to the pulp used in the present study, has great potential for the production of sugars via enzymatic catalysis aiming at the production of ethanol.