ABSTRAKEster asam lemak glukosa dapat disintesis secara enzimatis menggunakan katalis
lipase Candida rugosa E.C. 3.1.1.3 yang terimobilisasi pada nanopartikel Fe3O4-
kitosan. Nanopartikel Fe3O4-kitosan disintesis menggunakan metode
kopresipitasi, kemudian dikarakterisasi menggunakan FTIR (Fourier Transform
Infra Red), TEM (Transmission Electron Microscopy), dan VSM (Vibrating Sample
Magnetometer), dan FESEM (Field Emission Scanning Electron Microscopy).
Sintesis ester dilakukan dalam pelarut organik berbeda, yaitu metil isobutil keton
dan t-butanol. Proses imobilisasi lipase dilakukan dengan menggunakan bantuan
agen pengikat silang glutaraldehida. Persen loading imobilisasi lipase diperoleh
sebesar 68,15%. Aktivitas hidrolisis lipase terimobilisasi didapat sebesar 4,87 U/mg,
dengan aktivitas spesifik lipase sebesar 1,39 U/mg dan efisiensi imobilisasi sebesar
3,52%. Pada penelitian dilakukan variasi rasio substrat dan waktu reaksi untuk
mengetahui kondisi reaksi yang menghasilkan persen konversi tertinggi.
Diperoleh kondisi reaksi terbaik pada rasio substrat 1:30 dan waktu reaksi selama
16 jam untuk kedua pelarut. Reaksi esterifikasi menggunakan pelarut metal
isobutyl keton (MIBK) relatif menghasilkan persen konversi lebih besar dari tbutanol.
Pada kondisi optimum, diperoleh hasil sebesar 12,83% untuk MIBK dan
12,03% untuk t-butanol menggunakan enzim terimobilisasi. Pada pengunaan
lipase bebas diperoleh persen konversi sebesar 17,62% untuk pelarut t-butanol,
dan 18,07% untuk MIBK.
ABSTRACTGlucose fatty acid esters can be synthesized enzimatically using immobilized
Candida Rugosa lipase E.C. 3.1.1.3 on nanoparticle Fe3O4-chitosan. Nanoparticle
Fe3O4-chitosan were synthesized using co-presipitation method, and then
characterized using FTIR (Fourier Transform Infra Red), TEM (Transmission
Electron Microscopy), dan VSM (Vibrating Sample Magnetometer), dan FESEM
(Field Emission Scanning Electron Microscopy). Different organic solvents was
used for esterification, which was t-butanol and Methyl isobutyl ketone.
Glutaraldehyde was used as cross linking agent to aid the process of lipase
immobilization. Lipase was successfully immobilized with loading capacity of
68.15%. The obtained lipase hydrolysis activity was 4,87 U/mg, with
immobilization efficiency value of 3.52%. In this research, substrate ratio and
incubation time parameters were variated. The best condition of reaction was
obtained with substrate ratio of 1:30 and 16 hours of incubation time with both
solvents. Esterification using methyl isobutyl ketone (MIBK) as solvents was
found relatively has higher conversion rather than using t-butanol. The obtained
result for MIBK was 12.83% and 12,03% for t-butanol in esterificarion using
immobilized enzyme at the optimum conditions. The conversion percentage value
obtained for esterification using free lipase was 17,62% in t-butanol and 18,07%
in MIBK.