The main objective of this work was to immobilize the trypsin enzyme on cellulose fibers
extracted from passion fruit stalks, aiming to apply in the hydrolysis of rice bran protein
concentrate. In order to obtain the cellulose fibers, the passion fruit stalks were submitted to
pulping, bleaching and drying processes. Fibers were activated with glycidol (GLI) and
glutaraldehyde- ethylenediamine (GLU-EDA). Monitoring parameters were immobilization
yield, enzymatic activity, and operational stability. The results showed that the highest yield
system of immobilization was GLI-1 (test 1), with 49.98% ± 5.23%. The most activity retained
and the better operational stability was GLI-2 (test 2) system, obtaining values of 63.91% and
78.6%, respectively. The GLI-2 system was chosen to conduct hydrolysis of Rice Bran Protein
Concentrate (CPFA). The CPFA was prepared by fat extraction, solubilization and protein
precipitation. The result showed a 44% protein concentrate. The hydrolysis of the CPFA was
carried out at 37°C and pH 8 for 4 h using the enzyme immobilized at a ratio of 1:100 enzyme:
substrate (w/w). Monitoring tests were carried out by determination of the Degree of Hydrolysis
(GH). Free enzyme experiments were conducted as reference. The free enzyme GH was 7.95%
± 0.23. The last cycle performed with immobilized trypsin obtained a relative GH of 27.4%.
Even though it is a promising technique, this result shows that optimization studies should be
performed in order to hydrolysis system will be more efficient.
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