Judul: Sintesis Lipida Terstruktur Kaya Triasilgliserol tipe MLM (Medium-Long-Medium) dari Palm Olein Menggunakan Enzim Lipase Terimobilisasi.
Abstrak: Lipida terstruktur tipe Medium-Long-Medium (MLM) merupakan lipida terstruktur dengan asam lemak jenuh rantai sedang (C6-C12) pada posisi sn-1 dan sn-3 dengan asam lemak jenuh atau tidak jenuh rantai panjang (C14-C24) pada posisi sn-2. Jenis lipida ini memiliki berbagai manfaat antara lain memiliki nilai kalori yang rendah dan cocok digunakan untuk mengontrol obesitas, gangguan penyerapan lemak, dan gangguan metabolik lainnya. Saat MLM dikonsumsi, asam lemak rantai sedang pada posisi sn-1,3 lebih mudah untuk dihidrolisis oleh enzim lipase pankreas dan diserap ke dalam usus dan dibawa ke hati, serta memiliki kecenderungan untuk tidak disimpan dalam jaringan adiposa. Selain itu, asam lemak rantai panjang yang berada pada posisi sn-2 akan memudahkan penyerapan pada usus. Oleh karena itu, pengemabangan MLM sangat potensial dilakukan untuk memberikan berbagai manfaat bagi kesehatan. Penelitian ini bertujuan mensintesis lipida terstruktur tipe MLM (kaprilatoleat- kaprilat/ECN 32) dengan susbtrat berupa Refined Bleached Deodorized (RBD) Olein dan asam kaprilat atau trikaprilin. Reaksi ini dikatalis dengan menggunakan enzim Lipozyme® TL IM. Selain itu, pengaruh waktu reaksi dan jenis reaksi yang optimum pada sistem reaksi batch juga termasuk dalam tujuan penelitian. Penelitian ini dibagi menjadi 3 tahap yaitu : (i) karakterisasi susbtrat dan enzim yang digunakan, (ii) sintesis lipida terstruktur dan (iii) karakterisasi produk lipida terstruktur tipe MLM. Pada tahap karakterisasi bahan dilakukan analisis kadar air, kadar asam lemak bebas, dan komposisi TAG. Sedangkan karakterisasi Lipozyme® TL IM dilakukan dengan mengukur aw dan pHnya. Pada tahapan sintesis lipida terstruktur tipe MLM, reaksi transesterifikasi dan asidolisis serta analisis aktivitas esterifikasi dan residual activity enzim Lipozyme® TL IM diivestigasi. Selanjutnya, analisis komposisi triasilgliserol (TAG) dilakukan menggunakan metode HPLC dan fokus pada ECN 32 yang dihasilkan. Hasil penelitian menunjukkan bahwa reaksi asidolisis dan transesterifikasi dapat digunakan untuk mensintesis lipida terstruktur kaya TAG tipe MLM (kaprilat-oleat-kaprilat / ECN 32). Reaksi transesterfikasi membutuhkan waktu 4 jam reaksi untuk menghasilkan konsentrasi ECN 32 sebesar 16.75% sedangkan reaksi asidolisis membutuhkan waktu 20 jam untuk menghasilkan konsentrasi ECN 32 sebesar 16.28%. Selain itu, enzim Lipozyme® TL IM menunjukkan stabilitas operasional yang lebih baik pada reaksi transesterifikasi dibandingkan reaksi asidolisis. Hal ini dapat dilihat dari nilai waktu paruh enzim Lipozyme® TL IM yang lebih tinggi pada reaksi transesterfikasi (206.78 jam) dibandingkan reaksi asidolisis (182.42 jam). Oleh karena itu, sintesis MLM (COC/ECN32) dari RBD olein menggunakan enzim Lipozyme® TL IM lebih baik digunakan pada reaksi transesterfikasi.
Keyword: Lipase, Lipida Terstruktur, MLM, Palm Olein

Judul: Sintesis Lipida Terstruktur Tipe Medium-Long-Medium (MLM-SL) dengan Interesterifikasi Enzimatis dari Produk Minyak Sawit
Abstrak: Medium-long-medium structured lipid (MLM-SL) is a lipid with a specific arrangement of fatty acid at which medium chain fatty acids (MCFA/C6-C12) located at sn-1,3 positions and long chain fatty acids (LCFA/C14-C24) at sn-2 position. LCFA located at sn-1,3 positions show a low absorption coefficient due to their possibilities to react with calcium to produce calcium soap. Whereas, MCFA located at sn-1,3 position is easier to be hydrolyzed by the pancreatic lipase and have a little tendency to accumulate in adipose tissue. This indicates the combination of MCFA and LCFA on same triacylglycerol (TAG) molecule is very potential to be developed due to their nutritional benefits such as reduced calorie lipid, controlling obesity, and improve fat malabsorption. The primary objective of this study was to synthesize MLM-SL using palm oil products (palm olein and palm kernel oil) as substrates in batch and continuous system. To achieve the aforementioned primary objectives, this research was carried out through five main stages: (1) determining characteristics of substrates and blended substrates for MLM-SL synthesis; (2) selection of the suited reaction type for MLM-SL (between acidolysis and transesterification); (3) determination of the Lipozyme TL IM stability during acidolysis and transesterification of MLM-SL; (4) investigating the optimum reaction condition in batch and continuous system; (5) characterization of thermal properties of MLM-SL product. This dissertation is arranged to follow the stages of the research. In the first chapter, the comprehensive review about MLM-SL is reported to give recent updates on the MLM-SL synthesis through enzymatic reaction. The second chapter discusses about the suited reaction method (acidolysis or transesterification) for MLM-SL synthesis. In addition, this chapter also explains the stability of Lipozyme TL IM during MLM-SL synthesis. The third chapter disclose the MLM-SL synthesis in continuous operation using the suited reaction type previously determined. Moreover, the effect of enzyme loading and the information of productivity are provided as well. The last chapter describes the synthesis of MLM-SL using PKO as the alternative substrate for MCFA source. MLM synthesis was carried out in batch and continuous operation to determine the effect of substrate mol ratio, reaction time, and residence time. The results showed that palm olein-tricaprylin (transesterification) and palm olein - caprylic acid (acidolysis) were potentially to produce MLM-SL, especially 1,3-dicapryloyl-2-oleoyl-sn-glycerol (COC/ECN32). In general, new triacylglycerol (TAG) species was produced after acidolysis and transesterification reaction as compared to that their blended products. In batch-wise, transesterification reaction required a shorter reaction time (2-4 h) to produce high concentration of MLM-SL than that of acidolysis reaction (20 h). Moreover, Lipozyme TL IM shows better stability in the transesterification reaction as compared to that of acidolysis reaction. In continuous systems, 15 min of residence time and 2 g of enzyme loading were selected as optimal conditions of transesterification reaction due to their high concentration of MLM-SL and lower by-products (diacylglycerol/DAG, monoacylglycerol/MAG, free fatty acid/FFA, and glycerol). In addition, transesterification reaction between palm olein and palm kernel oil (PKO) was potentially to produce MLM-SL, especially 1,3-dilauryl-2-oleoyl-sn-glycerol (LaOLA/ECN40). In general, the increasing residence time or reaction time affects the possibility of producing higher by-products. Moreover, slip melting
Keyword: acidolysis, lipase, palm oil, structured lipid, transesterification

Judul: Keanekaragaman Spesies Burung pada Beberapa Ketinggian Tempat di Hutan Alam Kawasan Ciwidey Kabupaten Bandung
Abstrak: Bird diversity is influenced by some factors, such as altitude, vegetation and temperature. The objective of this research is to count the diversity and species richness, determine the relationship between bird diversity and altitude, temperature and tree diversity, also to map the dispersal of birds locally and vertically. The research was conducted in a natural forest at an elevation of 1600, 1800, 2000 and 2200 m asl at Ciwidey area, Bandung Regency. Temperature and humidity was measured by using a dry bulb & wet bulb thermometer. Vegetation data was collected by using square line method. Bird data was collected by using point count method. The number of species and the diversity index (H’) decreases as the altitude increase. The highest number of species and diversity index (H’) is at the altitude of 1600 m asl (41 species, H’=3,43). Results of the analysis using correlation test showed that the relationship between bird diversity correlates negatively with height (r=-0.97) and bird diversity correlates positively with temperature (r=0.95) or tree diversity (r=0.70).
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