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The low cost and excellent catalytic properties of lipase for industrial processes are highly desirable. A promising new approach involves the support modification of lipase and spacer arm, which enables the enhancement of lipase properties. This study investigates the immobilization of crude lipase from Mucor miehei onto a Polyurethane Foam (PUF) surface using various coating techniques. The PUF matrix was obtained through isocyanate and polyol reactions. Subsequently, the PUF was coated by adsorbing lipase and adding edible support material. The immobilized lipase was then utilized in the hydrolysis of coconut oil to produce fatty acids. Furthermore, the immobilized enzyme was employed in the esterification of fatty acids to produce bio-flavors. The results demonstrate that the attachment reaction using support material, namely lecithin, gelatin, MgCl2, and Polyethylene glycol 6000 (PEG), all of which are simple and edible, was able to enhance the stability and reusability of lipase. This immobilization technique increased triglyceride hydrolysis into FFA by 422%. The successful edible support modification of immobilized lipase from M. miehei on PUF, coupled with significantly enhanced enzyme stability and catalytic activity, offers a promising, environmentally friendly solution for diverse applications in the food industry. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Biokatalis heterogen memerlukan penyangga yang sesuai melalui teknik imobilisasi enzim, terutama jika digunakan dalam industri makanan. Dalam sintesis perisa ester alami, busa poliuretan (PUF) dipilih sebagai penyangga imobilisasi lipase, karena memiliki sifat kaku inert, dan porositas tinggi. PUF perlu dilapisi dengan co-immobilized, yang terdiri dari campuran surfaktan yang aman yaitu gelatin, lecithin, PEG, MgCl2, sehingga menjadi satu kesatuan sebagai penyangga PUF hidrofobik. Interaksi hidrofobik antara lipase dan surfaktan pada PUF dapat memicu lipase yang mengaktifkan antarmuka untuk bereaksi lebih banyak dengan substrat melalui sisi aktifnya. Penelitian ini bertujuan untuk mempelajari kemampuan penyerapan PUF pada co-immobilized lipase sebagai biokatalis heterogen. Tahapan yang dilakukan adalah PUF direndam dalam co-immobilized dengan perbandingan 1:10; 1:20; 1:30 (b/b) selama 1-5 jam, kemudian dikeringkan, hasilnya direndam dalam lipase dan dikeringkan, menghasilkan biokatalis heterogen, hasil terbaik biokatalis heterogen diuji pada sintesis perisa ester alami. Hasil penelitian menunjukkan bahwa kondisi penyerapan surfaktan terbaik diperoleh selama 3 jam perendaman pada semua perbandingan PUF: co immobilized 1:10; 1:20; 1:30 (b/b) masing - masing 6,95 g/g; 23,54 g/g; 19,95 g/g, dan aktivitasnya berturut turut 2 U/g PUF; 5,86 U/g PUF; 3,34 U/g PUF. Hasil biokatalis heterogen terbaik pada rasio PUF: co immobilized 1:20 (b/b) diuji pada sintesis perisa alami melalui reaksi esterifikasi asam laurat dari minyak kelapa dan sitronelol dari minyak sereh, menghasilkan konversi 55% perisa alami citronellyl laurat. Heterogeneous biocatalysts prepared through the enzyme immobilization technique require an appropriate carrier, especially if they are used in the food industry. In the synthesis of natural ester flavor, polyurethane foam (PUF) was chosen as the lipase immobilization carrier, because it has rigid properties, inert, and high porosity. Carrier PUF needs to be coated with a food-safe surfactant known as co-immobilized, consisting of a mixture of gelatin, lecithin, PEG, and MgCl2, so that it becomes a single unit as support for hydrophobic PUF. The interaction hydrophobic between lipases and surfactants in PUF can trigger interface-activating lipases to react more with substrates through their active sites. This study aims to study the sorption capability of PUF on co-immobilized lipase as a heterogeneous biocatalyst. The steps taken were PUF was immersed in co-immobilized in a ratio of 1:10; 1:20; 1:30 (w/w) for 1-5 h, then dried, the results were soaked in lipase and dried, producing heterogeneous biocatalysts, the best results of heterogeneous biocatalysts were tested by natural flavor ester synthesis. The results showed that the best sorption conditions were obtained for 3 hours of immersion in all PUF: immobilized co ratio 1:10; 1:20; 1:30 (w/w) was 6.95 g/g; 23.54 g/g; 19.95 g/g, and each activity was 2 U/gram PUF; 5.86 U/gram PUF; 3.34 U/gram PUF. The best result of heterogeneous biocatalyst at the ratio of PUF: co immobilized 1:20 (w/w) was tested on the synthesis of natural flavors through the esterification reaction of lauric acid from coconut oil and citronellol from citronella oil, resulting in a conversion of 55% to citronellyl laurate natural flavor.

The enzymatic hydrolysis of palm oil can be conducted by using lipase produced from Mucor miehei to produce free fatty acid. This study aimed to compare the usage of lipase as free enzyme and as immobilized enzyme on zeolite matrix in the hydrolysis of palm oil as triglyceride producing free fatty acids which highly needed in various industrial sectors. Immobilization is an alternative hydrolysis reaction due to its usage on repetitive reaction, makes lipase reuseable, hence the whole process becomes efficient, and with moderate operational conditions. Solvent free reaction is applied, because the produced free fatty acids can be used directly in food, health, and natural flavorings industry. The palm oil used in the hydrolysis contains 0.815% initial free fatty acids as palmitate, in which water then added to it in weight ratio 1:3. Each effect of free lipase and immobilized lipase addition is 4%, 5%, 6%, 7%, 8%, and time reaction is 30, 60, 90, 120, 150 minutes are used as index to determine the amount of free fatty acids produced. The results showed that Immobilized lipase has better ability than the free one in hydrolysis of triglyceride in palm oil producing free fatty acid with 8% lipase addition and time reaction of 120 minutes. Palm oil hydrolysis using free lipase produced the highest FFA of 1.9747% after the addition of 5% lipase concentrate, with time reaction of 60 minutes. Meanwhile, palm oil hydrolysis using immobilized lipase produced the highest FFA of 1.9747% after the addition of 8% lipase concentrate, with time reaction of 120 minutes.

A kinetic model was proposed for the synthesis of methane to be dimethyl ether (DME) in one reaction step from (CH4 + O2) and (CH3OH) to dimethyl ether using kinetic CuO-ZnO /Al2O3 catalyst parameters. The bifunctional catalyst of the series kinetic reaction model according to the experimental results obtained under isothermal conditions in a pipe flow reactor under various operating conditions: 225-325 ° C; 10 bar gauge; Residence time, 16-57.0 (g Catalyst) hour (mole CH4) -1. An important step for modeling is the synthesis of methanol from (CH4 + O2) and the synthesis of (CH3OH to DME) is methanol dehydration (very fast), and water-shifting and CO2 (equilibrium) reactions. The effects of water inhibition and CO2 were also taken into account in the synthesis of methanol and the formation of hydrocarbons. The dehydration advantage of methanol can achieve higher yields above 60 % methanol that was converted to DME and the remaining 5% methanol if (CH4 + O2) comes in at 10 bar gauge and 375 ° C. At higher temperatures produces CO2 and H2O. Methane-methanol-DME series reaction model follows single-order gas phase reaction to methane and methanol with k1 = 0.195 minutes-1 and k2 = 0.115 minutes-1 The time and maximum concentration occurs in the formation of methanol constituents 9.5 minutes and 0.44 mole

Free Fatty acid resulting from hydrolisis of various types of oil enzymatically has been great interest recently to save energy, in other hand that the product are environmentally friendly. Lipases as biocatalysts for synthesis reactions will be dissolved with the product, making difficult their reuse. Efficiency can be done with the use of enzyme immobilization, which can be used for repeated reaction. The products of free fatty acids from coconut oil by hydrolysis of lipase can be used as a natural substrate for making flavor that can be consumed and safe for health. The effect of free lipase and immobilization of lipase on hydrolisis were studied. Reaction time of hydrolisis was varied as 30, 60, 90, 120 and 150 minutes. The variation of concentration of lipase addition was 4, 5, 6, 7 and 8 % . The types of treatment were used in this research free lipase and the immobilized lipase. The results shows that the highest conversion on hydrolisis of coconut oil by using free lipase treatment was performed by 6 % of lipase addition with reaction time 60 minutes that are 52,31%. While, the highest conversion on hydrolisis of coconut oil by using the immobilized lipase was shown by 8% of lipase addition with reaction time 120 minutes that is 56,01%. The results of the hydrolysis process in the form of fatty acid was used as the base material esterification process resulting ester product (natural flavor). Ester yield was produced by free lipase esterification was 28,21 and 32,14 % in immobilized lipase esterification.

Syariah financing people bank so called as BPRS, give warranty to the borowers , that every operations free of elements gambling (maysir), uncertainty (gharar), and interest (riba). Warranty with a certain step to give an explanation and information of all the aspect of operational done by BPRS can be called as the transparency. Thus, improving the transparency in BPRS need to optimized. Transparency which includes a whole operational activities with the stakeholders need to be enhanced, because the lack of transparency could caused to uncertainty (gharar) that impact to the faith of stakeholders. This study aimed to explore in depth views relating to two things; first, the development of transparency on BPRS; especially in operational activities businesses and correlation with the stakeholders. Second, the role of information technology in the process of transparency, and its impact on BPRS or the National Economy.