%A  1317011021 Fathaniah Sejati
%T AMOBILISASI ENZIM ?-AMILASE  DARI Bacillus subtilis ITBCCB148 DENGAN MENGGUNAKAN ZEOLIT
%X Enzim ?-amilase merupakan enzim yang dapat memutus ikatan ?-1,4 glikosida pada amilum.  Enzim ini banyak dimanfaatkan dalam berbagai proses industri, baik industri pangan maupun non-pangan.  Dalam proses industri enzim harus mampu bekerja pada kondisi pH ekstrim serta mempunyai stabilitas termal yang tinggi.  Namun, umumnya enzim tidak stabil pada kondisi tersebut.
Penelitian ini bertujuan untuk meningkatkan stabilitas enzim ?-amilase dari isolat bakteri lokal Bacillus subtilis ITBCCB148 dengan amobilisasi menggunakan zeolit.  Untuk mencapai tujuan tersebut maka dilakukan proses produksi, isolasi, pemurnian, amobilisasi enzim, dan karakterisasi enzim ?-amilase sebelum dan sesudah amobilisasi.
Aktivitas spesifik enzim hasil pemurnian diperoleh sebesar 24.735,715 U/mg, meningkat 19 kali dibandingkan ekstrak kasar enzim yaitu 1.285,867 U/mg. Enzim hasil pemurnian bekerja optimum pada suhu 65?C, sedangkan enzim amobil pada suhu 75?C. Aktivitas sisa yang dihasilkan pada uji stabilitas termal pada suhu 65?C selama 100 menit terhadap enzim hasil pemurnian adalah sebesar 20%,  sedangkan enzim amobil sebesar 40%.  Data kinetika enzim hasil pemurnian diperoleh data KM = 7,543 mg mL 1, Vmaks = 147,058  ?mol mL-1  menit-1, t1/2 = 30 menit, ki = 0,023 menit-1 dan ?Gi = 103,65 kJ mol-1, sedangkan enzim amobil adalah KM = 6,779 mg mL-1, Vmaks = 97,087 ?mol mL-1 menit-1 , t1/2 = 49 menit, ki = 0,014 menit-1 dan ?Gi = 105,03 kJ mol-1.  Amobilisasi menggunakan zeolit telah berhasil meningkatkan 1,64 kali stabilitas termal enzim, yang ditunjukkan oleh penurunan nilai ki.
Kata kunci : ?-Amilase, Bacillus subtilis ITBCCB148, amobilisasi enzim, zeolit.


ABSTRACT


?-amylase is an enzyme that breaks ?-1-4 glycoside bond in amylum.  It has been widely used in a number of industrial processes such as food industry and non food industry.  In industrial process, this enzyme must be able to work in an extreme pH and temperature.  However, an enzyme is not normally stable in these conditions.
The objective of this research was to improve the stability of ?-amylase enzyme from local bacteria bacillus subtilis ITBCCB148 with immobilization using zeolite.  A sequential processes were conducted, such as by production, isolation, purification, immobilization, and characterization the ?-amylase before and after immobilization.
The specific activity  of purified enzyme was obtained 24735.715 U/mg, increased 19 times higher than the crude extract enzyme (1285.867 U/mg).  The purified enzyme worked well at 65?C and the immobilized at 75?C. From thermal stability test at 65?C for 100 minutes, residual activity of the purified and the immobilized enzyme were 20% and 40%, respectively.  Kinetic data of the purified enzyme were KM value = 7.543 mg mL 1, Vmaks = 147.058 ?mol mL-1 minute-1, t1/2 = 30 minutes, ki = 0.023 minute-1, and ?Gi = 103.65 kJ mol-1, while the immobilized were KM = 6.779 mg mL-1, Vmaks = 97.087 ?mol mL-1 minute-1, t1/2 = 49 minutes, ki = 0.014 minute-1 dan ?Gi = 105.03 kJ mol-1. Enzyme immobilization using zeolite has succeeded in increasing the thermal stability of the enzyme as much as 1.64 times, which is indicated by decrease of ki value.
Keywords : ?-amylase, Bacillus subtilis ITBCCB148, enzyme immobilization, zeolite.

%C UNIVERSITAS LAMPUNG
%D 2017
%I FAKULTAS MATEMATIKA DAN ILMU PENGETAHUAN ALAM
%L eprints27851