Ester 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.

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Glucose 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.