RESUMEN
The effect of magnetic Fe3O4 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 Fe3O4, 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 Fe3O4 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 Fe3O4 1.5 g/L. Simultaneously, compared with the blank, which the conversion of cellulose was 47.932%, the maximum celluloseconversion of samples with adding magnetic Fe3O4 was 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 Fe3O4 was the lowest in comparison with the blank. However, no significant differences were observed in the final pH of the hydrolysate.