TY  - JOUR
ID  - eprints13589
UR  - http://digilib.unila.ac.id/13589/
A1  - 0817011059, Sundari Riawati
Y1  - 2012/02/03/
N2  - Abstrak

Penelitian ini bertujuan untuk mempelajari pengaruh penambahan gliserol
dan sorbitol terhadap stabilitas enzim selulase dari Bacillus subtilis ITBCCB148.
Untuk mencapai tujuan tersebut dilakukan produksi, isolasi, dan pemurnian
enzim. Pemurnian enzim selulase dilakukan dengan menggunakan kromatografi
kolom filtrasi gel Sephadex G-100. Enzim hasil pemurnian kemudian
ditambahkan gliserol dan sorbitol. Penentuan aktivitas enzim selulase dilakukan
dengan metode Mandels sedangkan pengukuran kadar protein dilakukan dengan
metode Lowry.
Hasil penelitian menunjukkan bahwa enzim hasil pemurnian memiliki
aktivitas spesifik sebesar 4,6458 U/mg, meningkat 4,93 kali dibandingkan ekstrak
kasar enzim dengan perolehan 12,60%. Enzim ini memiliki pH optimum 5,5; suhu
optimum 50oC; ki = 0,0121 menit-1 ; t1/2 = 57,27 menit; dan ?Gi = 102,19 kJ mol-1.
Enzim setelah penambahan gliserol 0,5; 1,0; dan 1,5 M memiliki pH
optimum dan suhu optimum yang sama dengan enzim hasil pemurnian. Uji
stabilitas termal enzim setelah penambahan gliserol 0,5 M pada suhu 50oC selama
100 menit memiliki t1/2 = 72,19 menit, ki = 0,0096 menit-1 dan ?Gi = 102,82 kJ
mol-1; gliserol 1,0 M memiliki t1/2 = 82,50 menit, ki = 0,0084 menit-1 dan ?Gi =
103,17 kJ mol-1; dan gliserol 1,5 M memiliki t1/2 = 80,58 menit, ki = 0,0086
menit-1 dan ?Gi = 103,11 kJ mol-1.
Enzim setelah penambahan sorbitol 0,5; 1,0; dan 1,5 M memiliki pH
optimum dan suhu optimum yang sama dengan enzim hasil pemurnian. Uji
stabilitas termal enzim setelah penambahan sorbitol 0,5 M pada suhu 50oC selama
100 menit memiliki t1/2 = 90,00 menit, ki = 0,0077 menit-1 dan ?Gi = 103,41 kJ
mol-1; sorbitol 1,0 M memiliki t1/2 = 99,00 menit, ki = 0,0070 menit-1 dan ?Gi =
103,66 kJ mol-1; dan sorbitol 1,5 M memiliki t1/2 = 92,40 menit, ki = 0,0075
menit-1 dan ?Gi = 103,48 kJ mol-1.
Walaupun suhu optimum dan pH optimum enzim setelah penambahan
gliserol dan sorbitol tidak mengalami perubahan, tetapi terjadi peningkatan
stabilitas termal karena adanya penurunan nilai ki serta peningkatan waktu paruh
dan ?Gi.
Kata Kunci: Enzim selulase, gliserol, sorbitol, Bacillus subtilis ITBCCB148








Abstract

This research aims to study the effect of addition glycerol and sorbitol
toward stability cellulase enzyme from Bacilus subtilis ITBCCB148. To approach
this aims, the production, isolation and purification of the enzyme were done. The
purification of cellulase enzyme was done by using gel filtration chromatography
column of Sephadex G-100. The pure enzyme is added by glycerol and sorbitol.
Determination of cellulase enzyme activity performed by the method of Mandels
while the measurement of protein levels performed by the method of Lowry.
The results showed that the pure enzyme has specific activity 4,6458
U/mg, the pureness increase 4,93 times than native enzyme with the result
12,60%. This enzyme has optimum pH 5,5; optimum temperature 50°C; ki =
0,0121 min-1; t1/2 = 57,27 min; and ?Gi = 102,19 kJ mol-1.
Enzyme after addition glycerol 0,5; 1,0; and 1,5 M have optimum pH and
temperature same with pure enzyme. The test of thermal stability of the enzyme
after addition glycerol 0,5 M at temperature 50°C for 100 min has t1/2 = 72,19
min, ki = 0,0096 min-1 and ?Gi = 102,82 kJ mol-1; glycerol 1,0 M has t1 /2 = 82,50
min, ki = 0,0084 min-1 and ?Gi = 103,17 kJ mol-1; and glycerol 1,5 M has t1/2 =
80,58 min, ki = 0,0086 min-1 and ?Gi = 103,11 kJ mol-1.
Enzyme after addition sorbitol 0,5; 1,0; and 1,5 M have optimum pH and
temperature same with pure enzyme. The test of thermal stability of the enzyme
after addition sorbitol 0,5 M at temperature 50°C for 100 min has t1/2 = 90,00 min,
ki = 0,0077 min-1 and ?Gi = 103,41 kJ mol-1; sorbitol 1,0 M has t1/2 = 99,00 min,
ki = 0,0070 min-1 and ?Gi = 103,66 kJ mol-1, and sorbitol 1,5 M has t1/2 = 92,40
min, ki = 0,0075 min-1 and ?Gi = 103,48 kJ mol-1.
Although the optimum pH and temperature of the enzyme after addition
glycerol and sorbitol have not changed, but an increase in thermal stability due to
a decrease in the value of ki as well as increase half life and ?Gi.
Key word: Cellulase enzyme, glycerol, sorbitol, Bacillus subtilis ITBCCB148
JF  - Digital Library
TI  - STUDI PENGARUH PENAMBAHAN GLISEROL DAN SORBITOL
TERHADAP STABILITAS ENZIM SELULASE DARI Bacillus subtilis
ITBCCB148
AV  - restricted
ER  -