PENGARUH PENAMBAHAN SORBITOL TERHADAP STABILITAS ENZIM SELULASE DARI Aspergillus fumigatus
| Main Author: | Juwita Ria, 1617011009 |
|---|---|
| Format: | Bachelors NonPeerReviewed Book Report |
| Terbitan: |
FAKULTAS MATEMATIKA DAN ILMU PENGETAHUAN ALAM
, 2020
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| Subjects: | |
| Online Access: |
http://digilib.unila.ac.id/65464/1/ABSTRAK.pdf http://digilib.unila.ac.id/65464/2/SKRIPSI%20FULL.pdf http://digilib.unila.ac.id/65464/3/SKRIPSI%20TANPA%20BAB%20PEMBAHASAN.pdf http://digilib.unila.ac.id/65464/ |
Daftar Isi:
- Enzim selulase adalah enzim yang dapat menghidrolisis ikatan (1,4) glikosidik pada selulosa. Enzim biasanya tidak stabil dalam keadaan pH dan suhu yang ekstrim. Penelitian ini bertujuan untuk mempelajari pengaruh penambahan sorbitol terhadap stabilitas enzim selulase dari Aspergillus fumigatus. Untuk mencapai tujuan tersebut, telah dilakukan produksi, isolasi, pemurnian dengan menggunakan ammonium sulfat dan dialisis, penambahan sorbitol, serta karakterisasi enzim selulase hasil pemurnian dan hasil penambahan sorbitol. Uji aktivitas enzim ditentukan dengan metode Mandels dan kadar protein dengan metode Lowry. Hasil penelitian diperoleh aktivitas spesifik enzim selulase hasil pemurnian adalah 1,72 U/mg meningkat sebanyak 6,3 kali dari ekstrak kasarnya yang mempunyai aktivitas spesifik 0,27 U/mg. Enzim hasil pemurnian dan penambahan sorbitol 0,5 M; 1 M; dan 1,5 M mempunyai pH optimum 4 dan suhu optimum 60° C. Enzim hasil pemurnian memiliki nilai KM= 17,874 mg/mL substrat; Vmaks= 20,202 mol/mL.menit; ki= 0,006/menit; t1/2= 115,5 menit; dan Gi= 107,3754 kJ/mol. Enzim hasil penambahan sorbitol 0,5 M; 1 M; dan 1,5 M memiliki berturut-turut nilai KM= 4,901; 9,137; dan 10,070 mg/mL; Vmaks berturur-turut adalah 8,896; 7,535; dan 17,180 μmol/mL.menit; ki berturut-turut adalah 0,0045; 0,0042; dan 0,0025 menit-1 ; t1/2 berturut-turut adalah 154; 165; dan 277,2 menit; serta nilai Gi berturut-turut adalah 108,1720; 108,3630; dan 109,7995 kJ/mol. Berdasarkan penurunan nilai ki, peningkatan nilai Gi dan t1/2, disimpulkan bahwa penambahan sorbitol dapat meningkatkan stabilitas enzim selulase dari Aspergillus fumigatus sebesar 1,3-2,4 kali dari enzim hasil pemurnian. Keyword: Selulase, Aspergillus fumigatus, Selulosa, Stabilitas Enzim, Sorbitol ABSTRACT Cellulase is an enzyme that can hydrolyze (1.4) glycosidic bonds in cellulose. Enzymes are usually unstable in conditions of extreme pH and temperature. This study aims to study the effect of sorbitol addition on the stability of the cellulase from Aspergillus fumigatus. To achieve these objectives, production, isolation, purification using ammonium sulfate and dialysis have been carried out, the addition of sorbitol, and characterization of the cellulase enzyme from the purification results and the addition of sorbitol. The enzyme activity test was determined by the Mandels method and protein content by the Lowry method. The results showed that the specific activity of the purified cellulase enzyme was 1.72 U/mg, an increase of 6.3 times from the crude extract which had a specific activity of 0.27 U/mg. The enzyme was purified and added by 0.5 M sorbitol; 1 M; and 1.5 M has an optimum pH of 4 and an optimum temperature of 60°C. The purified enzyme has a value of KM = 17.874 mg / mL of the substrate; Vmax = 20.202 mol/mL.minutes; ki = 0.006/minute; t1/2 = 115.5 minutes; and Gi = 107.3754 kJ/mol. The purified enzyme after adding 0.5 M sorbitol; 1 M; and 1.5 M, respectively, have a value of KM = 4.901; 9.137; and 10.070 mg/mL; Vmax value: 8.896; 7.535; and 17.180 μmol/mL.minutes; ki value: 0.0045; 0.0042; and 0.0025 minutes-1; half-life (t1/2): 154; 165; and 277.2 minutes; and the value of Gi: 108.1720; 108.3630; and 109.7995 kJ/mol. Based on the decrease in the value of ki, the increase in the value of Gi and t1/2, it is concluded that the addition of sorbitol could increase the stability of the cellulase enzyme from Aspergillus fumigatus by 1.3-2.4 times that of the enzyme purified. Keyword : Cellulase, Aspergillus fumigatus, cellulose, enzyme stability, sorbitol