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Abstrak :
Candida rugosa lipase terimmobilisasi digunakan sebagai biokatalis dalam reaksi interesterifikasi minyak goreng bekas dengan metil asetat pada reaktor packed bed. Reaktan dan produk dianalisa menggunakan HPLC. Pengaruh waktu tinggal terhadap konversi biodiesel dan stabilitas dari biokatalis yang digunakan diteliti lebih lanjut. Hasil penelitian menunjukkan bahwa biokatalis ini dapat mengkonversi 71,5% trigliserida dari minyak kelapa sawit bekas. Uji stabilitas menunjukkan bahwa biokatalis terimmobilisasi ini masih memiliki aktivitas yang baik untuk 50 jam reaksi secara kontinyu. Model kinetika berbasis Ping Pong Bi Bi mampu menggambarkan reaksi ini dengan ditandai hasil fitting yang cukup sesuai dengan data hasil eksperimen. ......Immobilized Candida rugosa lipase is used as a biocatalyst in interesterification of used cooking oil with methyl acetate in packed bed reactor. The reactants and products were analyzed using HPLC. The effect of residence time and operational stability were investigated. The result showed that this biocatalyst can convert 71,5% fatty acid from triglyceride in used palm oil. Stability test showed that this immobilized biocatalyst had still good activity for 50 hour without appreciable loss in substrate conversion. Kinetic model based on Ping Pong Bi Bi Menten mechanism can describe this reaction with comparing experiment data result to fitting data result.

Abstrak :
Penelitian ini telah memproduksi wax ester berbahan dasar asam oleat dan oktanol menggunakan biokatalis Candida rugosa lipase. Beberapa variasi dilakukan untuk mengetahui kondisi operasi optimum, seperti persentase enzim, rasio reaktan (asam oleat:oktanol), dan waktu reaksi. Dari variasi tersebut didapatkan konversi optimum 69,76 % untuk 4 % enzim dengan rasio reaktan 1:1 selama 6 jam reaksi. Konversi maksimum sebesar 87,5 % diperoleh untuk kondisi operasi yang sama dengan penambahan 8 % enzim. Kinetika reaksi juga dibuat berdasarkan persamaan Michaelis-Menten. Dengan persamaan ini, didapatkan parameter Km dan vmax masing-masing sebesar 0,417 dan 2,435. ......The lipase catalyzed reaction of wax esters synthesis using oleic acid and long chain alcohol (octanol) as substrates and Candida rugosa lipase (CRL) as biocatalist was carried out. The effects of various reaction parameters such as molar ratio of substrates, amount of enzyme, and reaction time were investigated. The optimum reaction condition for wax ester synthesis is a mixture of oleic acid and octanol with molar ratio of 1:1, with 4% (w/w) CRL for 6 h. Percentage conversion of wax esters obtained at these optimum reaction conditions was 69,76 %. Maximum conversion (87,5 %) obtained by addition of 8 % CRL with the same reaction condition. Kinetic were also studied using Michaelis-Menten kinetic model. By using this equation, the Km and vmax parameter can be solved with the value of 0,417 and 2,435 respectively.

Abstrak :
Sintesis biodiesel dengan proses sirkulasi pada reaktor unggun diam dirancang dengan memanfaatkan enzim lipase. Lipase dari Candida rugosa diimobilisasi pada kalsium alginat dan digunakan sebagai biokatalis pada reaktor. Kesesuaiian substrat diuji dengan penggunaan pelarut, metode penambahan bertahap, dan tanpa pelarut. Kalsium alginat menghambat difusivitas substrat menuju inti aktif enzim sehingga menyebabkan laju sintesis yang lambat di awal proses. Sintesis menggunaan metode penambahan bertahap mampu menghasilkan yield paling tinggi diantara pengujian substrat lain, sebesar 88,70% dalam 24 jam. Laju alir optimal yang didapatkan adalah 0,4 dan 1 ml/menit, menghasilkan biodiesel dalam laju konversi yang lebih tinggi. Konsentrasi optimal enzim lipase yang terimobilisasi adalah 0,2%(w/v minyak). Sintesis pada kondisi optimal mencapai yield 70,2% dalam 12 jam. Pengujian stabilitas enzim amobil dilakukan dan mampu menghasilkan 65,6% biodiesel pada siklus ke-tiga, mempertahankan 93,4% aktivitas relatif enzim terimobilisasi. Model kinetika berbasis Ping Pong Bi Bi dikembangkan dengan mengkosiderasi konsentrasi alkohol. Model diaplikasikan untuk memprediksi konsentrasi reaktan dan produk selama sintesis biodiesel di reaktor kolom isian. Pemodelan di excel menunjukkan bahwa model yang dihasilakn dapat memprediksi konsentrasi komponen dalam reaksi transesterifikasi. ......A packed bed reactor with circulation process was designed to synthesize biodiesel utilizing lipase enzyme. Candida rugosa lipase was immobilized in calcium alginate and used as biocatalyst in reactor. Compatibility of substrate was tested using the usage of solvent hexane, stepwise addition, and without solvent. It was found that calcium alginate limit the diffusivity of substrate causing slow reaction rate at the start of process. Stepwise addition method was found to be the most optimum compared to others in this research, producing yield 88.7% in 24 hours. Optimal flowrate are 0.4 and 1 ml/min, producing biodiesel at higher rate. Optimal concentration of lipase immobilized in calcium alginate is 0.2% of substrate. Synthesis under optimal condition produces yield 70.2% in 12 hours. Stability test of immobilized enzyme retains 93.4% of relative activity, obtaining yield 65.6% in 12 hours. The kinetic model based on Ping Pong Bi Bi was developed by considering alcohol concentration. The model was applied to predict the concentration of reactants and products during biodiesel synthesis in the filling column reactor. Modeling in excel shows that the resulting model can predict the concentration of components in the transesterification reaction.

Abstrak :
Lipase merupakan enzim yang umum diaplikasikan sebagai katalis, baik pada industri pangan maupun proses sintesis bioplastik, seperti Poli Asam Laktat (PLA), dimana lipase Candida rugosa (CRL) menjadi salah satu jenis enzim lipase yang banyak digunakan. Namun, tingginya suhu operasi pada industri maupun sintesis bioplastik dapat mendenaturasi enzim sehingga mempengaruhi aktivitas karena terjadinya perubahan struktur enzim. Proses imobilisasi CRL dapat dilakukan guna meningkatkan stabilitas termal enzim. Pada penelitian ini proses imobilisasi dilakukan melalui metode adsorpsi pada matriks pendukung padat, yaitu Celite. Imobilisasi enzim melalui metode adsorpsi dipengaruhi oleh kondisi operasinya, seperti waktu, suhu, dan pH imobilisasi. Penelitian ini dilakukan dengan beberapa variasi, yaitu jenis larutan pencuci, konsentrasi enzim, suhu imobilisasi, waktu imobilisasi, pH imobilisasi, dan rasio pelarut terhadap buffer. Analisis enzim terimobilisasi dilakukan terhadap aktivitas esterifikasi, stabilitas termal, dan kandungan proteinnya. Penelitian menunjukkan jenis larutan pencuci, konsentrasi enzim, suhu imobilisasi, waktu imobilisasi, pH imobilisasi, dan rasio pelarut terhadap buffer dengan hasil optimal adalah etanol; 35 mg/mL; 60 menit; 6,5; dan 2,75 (v/v) secara berturut-turut. Enzim terimobilisasi pada penelitian ini menghasilkan aktivitas esterifikasi 76% lebih tinggi daripada enzim bebas pada suhu 37°C. Imobilisasi juga meningkatkan stabilitas termal enzim sebesar 29-51% pada suhu esterifikasi tertentu. ......Lipase is an enzyme that is commonly applied as a catalyst, both in the food industry and in the synthesis of bioplastics, such as Poly Lactic Acid (PLA), where Candida rugosa lipase (CRL) is one of the widely used lipases. However, high operating temperatures in industry and bioplastic synthesis can denature enzymes, thereby affecting activity due to changes in enzyme structure. The CRL immobilization process can be carried out to improve the thermal stability of the enzyme. In this study, the immobilization process was done through the adsorption method on a solid support matrix, that is Celite. Enzyme immobilization through the adsorption method is influenced by its operating conditions, such as time, temperature, and pH of immobilization. The study was carried out by varying the washing solution type, enzyme concentrations, immobilization temperatures, immobilization time, immobilization pH, and the ratio of solvent to buffer. The immobilized enzyme analysis was performed on the esterification activity, thermal stability, and protein content. The study showed that the washing solution type, enzyme concentration, immobilization temperature, immobilization time, immobilization pH, and the ratio of solvent to buffer with optimal results were ethanol, 35 mg/mL, 60 minutes, 6.5, and 2.75 (v/v) respectively. The immobilized enzyme in this study resulted in 76% higher esterification activity than the free enzyme at 37°C. Immobilization also increases the thermal stability of the enzyme by 29-51% at a certain esterification temperature.

Abstrak :
PLA merupakan salah satu polimer yang dapat digunakan sebagai alternatif pengganti plastik karena sifatnya kelebihannya yaitu biodegradabel, biokompatibilitas, kekuatan mekanik, dan kemampuan proses. Proses sintesis PLA akan dilakukan dengan menggunakan jalur Polimerisasi Pembukaan Cincin (PPC) dengan pertimbangan dapat menghasilkan berat molekul PLA yang tinggi dengan bantuan katalis dan pelarut. Katalis yang digunakan adalah katalis Lipase Candida rugosa dan pelarut yang digunakan adalah DMA (dimethylacetamide). Penelitian ini akan dilakukan dengan beberapa variasi yaitu variasi waktu pada 2, 3, 4 hari; variasi suhu pada 60ᵒC, 80ᵒC, 100ᵒC; dan rasio katalis pada 2, 5, dan 10% b/b. PLA yang telah tersintesis akan dilakukan uji karakterisitik yaitu berat molekul rata-rata jumlah (Mn), konversi monomer, dan struktur molekul menggunakan H1 NMR. Hasil penelitian ini berupa spektra NMR dan digunakan untuk menghitung nilai konversi dan Mn PLA. Didapatkan bahwa suhu, rasio katalis, dan waktu reaksi polimerisasi yang optimal adalah pada suhu 80℃, rasio katalis sebesar 5%, dan waktu reaksi 3 hari dengan menghasilkan konversi sebesar 99,48% dan Mn sebesar 1192,07 g/mol. ......PLA is a polymer that can be used as an alternative to fossil-based plastics. PLA is the right solution because of its biodegradability, biocompatibility, mechanical strength, and processability. The PLA synthesis process will be carried out using the Ring Opening Polymerization (PPC) pathway with the consideration can produce a high molecular weight of PLA with the help of catalysts and solvent. This study used a Candida rugosa lipase as a green catalyst and DMA (Dimethylacetamide) as a solvent. The observations were made by varying time at 2, 3, 4 days; temperature at 60ᵒC, 80ᵒC, 100ᵒC; and catalyst ratio at 2, 5, and 10% w/w. The PLA will be characterized which are molecular weight average number (Mn), monomer conversion, and molecular structure using H1 NMR. The results of this study were in the form of NMR spectra and used to calculate the monomer conversion and Mn PLA. It was found that the optimal temperature, catalyst ratio, and polymerization reaction time were at 80℃, the catalyst ratio was 5%, and the reaction time was 3 days with the conversion of 99.48% and Mn of 1192.07 g/mol.

Abstrak :
Ester asam oleat-sorbitol dapat disintesis secara enzimatis dengan katalis lipase yang terimobilisasi pada nanopartikel Fe3O4-Polidopamin. Pada penelitian ini, nanopartikel Fe3O4 dapat disintesis dengan menggunakan metode kopresipitasi, kemudian dimodifikasi dengan polidopamin. Karakterisasi pada nanopartikel Fe3O4, Fe3O4-Polidopamin, dan Fe3O4-Polidopamin-Lipase dilakukan dengan menggunakan FESEM-EDS (Field Emission Scanning Electron Microscopy-Energy Dispersion X-Ray Spectroscopy), XRD (X-Ray Diffraction), PSA (Particle Size Analyzer), VSM (Vibrating Sample Magnetometer), dan FT-IR (Fourrier Transformation-Infra Red). Hasil ester yang diperoleh dikarakterisasi dengan FT-IR, TGA (Thermogravimetric Analysis), dan uji emulsi sederhana. Hasil yang diperoleh dari analisis menggunakan FESEM didapatkan rata-rata ukuran dari nanopartikel Fe3O4 sebesar 32-58 nm dan nanopartikel Fe3O4-Polidopamin sebesar 35-77 nm. Dari penentuan persen loading lipase yang terimobilisasi diperoleh nilai sebesar 98,64%. Pada penelitian ini, dilakukan optimasi reaksi esterifikasi asam oleat dengan sorbitol menggunakan lipase terimobilisasi pada nanopartikel Fe3O4-Polidopamin dengan variasi rasio sorbitol:asam oleat, yaitu 1:30, 1:60, dan 1:90 serta pelarut organik yang digunakan adalah t-Butanol dan Metil-Isobutil-Keton (MIBK). Hasil penelitian ini menunjukkan bahwa kondisi optimum esterifikasi diperoleh pada rasio substrat 1:30 dengan menggunakan pelarut t-Butanol, dengan nilai persen konversi sebesar 23,56%. ...... Sorbitol-oleic esters could be produced by esterification reaction using immobilized Candida rugosa lipase on Fe3O4-Polydopamine nanoparticles. In this study, Fe3O4 nanoparticles were synthesized by coprecipitation method and then modified using Polydopamine. Characterization of Fe3O4 nanoparticles, Fe3O4-Polidopamin, and Fe3O4-Polidopamin-Lipase is conducted by using FESEM (Field Emission Scanning Electronic Microscopy), EDS (Energy Dispersive Spectroscope), XRD (X-Ray Diffraction), PSA (Particle Size Analyzer), VSM (Vibrating Sample Magnetometer), and FT-IR (Fourrier Transformation-Infra Red). The esterification product was then characterized by using FT-IR, TGA (Thermogravimetric Analysis), and simple emulsion test. Using FESEM analysis, it was found that average particle size of Fe3O4 nanoparticles were 32-58 mm and nanopraticles Fe3O4-Polidopamin were 35-77 nm. The loading percentage of immobilized lipase on Fe3O4-Polidopamin was 98,64%. To optimize the esterification reaction using immobilized lipase on Fe3O4- Polidopamin the substrate ratio of sorbitol:oleic acid were varied, which are 1:30, 1:60, and 1:90. The variation of organic solvent used in this study were t-Butanol and Metyl-Isobutyl-Keton (MIBK). Research also found that the highest conversion percentage value was obtained in substrate-ratio 1:30 using t-Butanol as solvent, with the conversion value of 23,56%.

Abstrak :
Ester asam lemak kelapa sawit sukrosa dapat disintesis melalui reaksi esterifikasi enzimatis menggunakan lipase Candida rugosa. Pada penelitian ini, digunakan pelarut isoamil alkohol dan isobutanol. Reaksi esterifikasi menggunakan lipase Candida rugosa E.C.3.1.1.3 bebas maupun terimobilisasi pada nanopartikel Fe3O4-kitosan. Imobilisasi lipase Candida rugosa pada nanopartikel Fe3O4-kitosan menggunakan metode ikat silang dengan glutaraldehida sebagai agen pengikat silang. Terhadap hasil imobilisasi dilakukan uji aktivitas dan persen loading. Pada peggunaan enzim 200 ppm didapatkan persen loading imobilisasi lipase sebesar 31,4% dengan aktivitas hidrolisis lipase terimobilisasi sebesar 3,470 U/mL, aktivitas spesifik 0,991 U/mg, serta efisiensi imobilisasi sebesar 23,25 %. Sementara itu, pada penggunaan 350 ppm enzim didapatkan persen loading imobilisasi lipase sebesar 64,4 % dengan aktivitas hidrolisis lipase terimobilisasi sebesar 2,245 U/mL, aktivitas spesifik 0,64 U/mg, serta efisiensi imobilisasi sebesar 14,88%. Kondisi rasio substrat optimum diperoleh pada rasio 1 : 90 (sukrosa : asam lemak). Hasil uji emulsifer menunjukkan hasil positif. Pelarut terbaik untuk sintesis ester -sukrosa dengan lipase terimobilisasi adalah isobutanol.

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Palm oil fatty acid-sucrose can be synthesized via enzymatic esterification using Candida rugosa lipase. The solvents used in this study were isoamyl alcohol and isobutanol. Esterification reaction was carried out enzymatically using free lipase and immobilized Candida rugosa lipase E.C. 3.1.1.3 on Fe3O4-chitosan nanoparticles. The immobilized lipase were examined to determine the loading percentage and the hydrolytic activity. The loading percentage obtained while using 200 ppm lipase for immobilization was 31,4%, with hydrolytic activity of immobilized lipase was 3,47 U/mL, the specific activity of 0,99 U/mg and the immobilization efficiency of 23,25%. Meanwhile by using 350 ppm lipase the loading percentage obtained was 64,4% with hydrolytic activity of 2,25 U/mL, the specific activity of 0,64 U/mg and the immobilization efficiency of 14,8 %. From this optimization study of esterification, the highest conversion came from sugar and fatty acid ratio 1 : 90. The esterification product gave positive test on emulsifier test. The best solvent to synthesize ester-sucrose using immobilized lipase is isobutanol.

Abstrak :
[SFAEs (Sugar Fatty Acid Esters) atau ester asam lemak-gula dapat disintesis enzimatis menggunakan lipase Candida rugosa E.C.3.1.1.3 terimobilisasi pada nanopartikel Fe3O4-Kitosan antara asam lemak hidrolisat minyak sawit dan fruktosa. Nanopartikel Fe3O4-Kitosan disintesis dengan metode kopresipitasi dan dikarakterisasi menggunakan FTIR (Fourier Transform Infra Red), FESEM (Field Emission Scanning Electron Microscopy), TEM (Transmission Electron Microscopy), dan VSM (Vibrating Sample Magnetometer). Esterifikasi dilakukan menggunakan lipase terimobilisasi untuk pemakaian pertama dan berulang. Nilai persen loading pada lipase terimobilisasi yang diperoleh adalah sebesar 68,15%. dengan aktivitas sebesar 1,39 U/mg dan efisiensi imobilisasi sebesar 3,52%. Untuk lipase terimobilisasi pemakaian kedua didapatkan aktivitas spesifik sebesar 0,51 U/mg dengan efisiensi imobilisasi sebesar 1,28%. Reaksi esterifikasi dilakukan dalam pelarut organik yang berbeda yaitu t-butanol dan metil isobutil keton (MIBK). Persen konversi tertinggi diperoleh dengan pelarut t-butanol sebesar 28,09% dengan derajat substitusi (DS) ester 3 menggunakan lipase bebas, 21,80% dengan DS ester 2 menggunakan lipase terimobilisasi dan 16,81% dengan DS ester 2 menggunakan lipase terimobilisasi pemakaian kedua. ......Sugar Fatty Acid Esters (SFAEs) can be synthesized by an enzymatic esterification between palm oil fatty acid and fructose using immobilized Candida rugosa lipase E.C.3.1.1.3 on Fe3O4-Chitosan nanoparticles. Fe3O4-Chitosan nanoparticles were synthesized by using coprecipitation method and characterized using FTIR (Fourier Transform Infra Red), FESEM (Field Emission Scanning Electron Microscopy), TEM (Transmission Electron Microscopy), and VSM (Vibrating Sample Magnetometer). The esterification reaction was performed using immobilized lipase for first and second usage. The loading percentage value of immobilized lipase obtained in this study was 68.15% with the specific avtivity of the immobilized lipase and immobilization efficiency was 3.52%. For the second usage of immobilized lipase, the specific activity obtained was 0.51 U/mg and immobilization efficiency obtained was 1.28%. The solvents used in the esterification reaction are t-butanol and methyl isobutyl ketone (MIBK). The highest percentage conversion was obtained in t-butanol as a solvent using free lipase with the value of 28.09% and degree of substitution (DS) value of ester was 3. The conversion percentage using immobilized lipase was 21.80% and DS value of ester was 2. Last but not least, for the second usage of immo., Sugar Fatty Acid Esters (SFAEs) can be synthesized by an enzymatic esterification between palm oil fatty acid and fructose using immobilized Candida rugosa lipase E.C.3.1.1.3 on Fe3O4-Chitosan nanoparticles. Fe3O4-Chitosan nanoparticles were synthesized by using coprecipitation method and characterized using FTIR (Fourier Transform Infra Red), FESEM (Field Emission Scanning Electron Microscopy), TEM (Transmission Electron Microscopy), and VSM (Vibrating Sample Magnetometer). The esterification reaction was performed using immobilized lipase for first and second usage. The loading percentage value of immobilized lipase obtained in this study was 68.15% with the specific avtivity of the immobilized lipase and immobilization efficiency was 3.52%. For the second usage of immobilized lipase, the specific activity obtained was 0.51 U/mg and immobilization efficiency obtained was 1.28%. The solvents used in the esterification reaction are t-butanol and methyl isobutyl ketone (MIBK). The highest percentage conversion was obtained in t-butanol as a solvent using free lipase with the value of 28.09% and degree of substitution (DS) value of ester was 3. The conversion percentage using immobilized lipase was 21.80% and DS value of ester was 2. Last but not least, for the second usage of immo]

Abstrak :
Ester asam lemak sakarida dapat diperoleh melalui reaksi esterifikasi antara maltosa dengan asam lemak minyak sawit menggunakan pelarut organik. Reaksi esterifikasi dilakukan secara enzimatik menggunakan katalis lipase Candida rugosa E.C.3.1.1.3 terimobilisasi pada nanopartikel Fe3O4-Kitosan, dengan pelarut isoamil alkohol dan iso butanol. Imobilisasi lipase Candida rugosa pada nanopartikel Fe3O4-Kitosan menggunakan metode ikat silang dengan glutaraldehida sebagai agen pengikat silang. Imobilisasi dilakukan menggunakan larutan lipase dengan konsentrasi awal enzim yaitu 200 dan 350 ppm. Variasi yang dilakukan menggunakan perbandingan rasio mol substrat gula: asam lemak, yaitu 1:30 ; 1:60 ; dan 1:90. Hasil yang lebih baik diperoleh menggunakan konsentrasi awal lipase 200 ppm, dengan nilai persen loading imobilisasi lipase yang diperoleh adalah 31,28 % dan aktivitas hidrolisis lipase terimobilisasi sebesar 2,88 U/mL dan aktivitas spesifiknya sebesar 1,23 U/mg. Hasil optimasi perbandingan rasio molar gula dan asam lemak menunjukkan kondisi optimum diperoleh pada rasio 1 : 30 menggunakan pelarut iso butanol, dengan % konversi 5,0 %. Hasil uji emulsifier menunjukkan bahwa produk esterifikasi dapat berfungsi sebagai emulsifier.

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Sugar esters can be produced with esterification between maltose and palm oil fatty acid in organic solvents. Esterification reaction was carried out enzymatically using immobilized Candida rugosa lipase EC.3.1.1.3 on Fe3O4--chitosan nanoparticles, with isoamyl alcohol and isobutanol as the solvents. Candida rugosa lipase was immobilized on Fe3O4-chitosan nanoparticles using cross-linking method with glutaraldehyde as cross linker. Immobilization was carried out with two initial enzyme concentrations of 200 and 350 ppm. The variations of molar substrate ratio of sugar : fatty acid used in this study were 1:30, 1:60, and 1:90. The optimal results was obtained using initial concentration of 200 ppm lipase. The loading percentage of immobilized lipase was 31,28 % with hydrolytic activity of immobilized lipase was 2,88 U/mL and the specific activity was 1,23 U/mg. The highest % conversion in esterification obtained in this study was 5.0 %, using molar ratio 1:30 in iso bthanol as solvent. The ester product obtained was then examined by simple emulsion test and can be used as an emulsifying agent.