The effect of magnetic Fe_3O_4 particles on cellulase in the enzymatic hydrolysis of sunflower seed hull was studied in different adding ways and additive amount. In the process of enzymatic hydrolysis of sunflower seed hull, the variations of cellulase activity, reducing sugar concentration and cellulose conversion were evaluated. After the reaction, the analysis of pH and surface tension of hydrolysate were also used to determine the mechanisms of cellulase by the magnetic effect. The results indicated that after adding magnetic Fe_3O_4, the cellulase activity, reducing sugar concentration and conversion of cellulose had an increased between the 0.5 g/L and 2.0 g/L cases after 48 h. When the additive amount of magnetic Fe_3O_4 was 2 g/L, the cellulase activity at 60 h was improved significantly by 25.9%. It was found that the concentration of reducing sugar was increased from 6.950 mg/mL to 8.775 mg/mL with magnetic Fe_3O_4 1.5 g/L. Simultaneously, compared with the blank, which the conversion of cellulose was 47.932%, the maximum cellulose conversion of samples with adding magnetic Fe_3O_4was 60.531%. Besides, the stability of cellulase activity adding in times was better than in one time. After the reaction, the final surface tension of hydrolysate with 1.5 g/L magnetic Fe_3O_4was the lowest in comparison with the blank. However, no significant differences were observed in the final pH of the hydrolysate.%将磁化后的Fe_3O_4微粒添加于葵花籽壳酶水解过程中,分析在不同的Fe_3O_4添加量和不同的添加方法下,葵花籽壳酶水解过程中纤维素酶酶活、纤维素转化率及还原糖浓度的变化特征,研究磁性Fe_3O_4微粒对纤维素酶水解葵花籽壳的影响.并通过考察酶水解反应前后水解液的表面张力值和pH值的变化,探讨和分析磁性Fe_3O_4微粒作用下纤维素酶的磁效应机制.结果表明,磁性Fe_3O_4添加量为0.5 g/L～2.0 g/L时,对纤维素酶酶活的提高,还原糖浓度的增加和纤维素的转化在48 h后表现出较明显的促进作用.磁性Fe_3O_4添加量为2 g/L时,纤维素酶60 h酶活最高可提高25.9%.添加量为1.5 g/L时,还原糖浓度从6.950 mg/mL提高到8.775 mg/mL;同时,添加Fe_3O_4微粒的样品中纤维素的最高转化率达60.531%,明显高于不添加Fe_3O_4样品的纤维素转化率47.932%.此外,分次添加磁性Fe_3O_4的酶活稳定性要优于一次添加.反应结束后,与不添加磁性Fe_3O_4的水解液相比,磁性Fe_3O_4添加量为1.5g/L时,水解液的表面张力值降低程度最大.但添加磁性Fe_3O_4微粒的水解液pH值变化不显著.
展开▼
