Judul: Pemanfaatan Pati Garut Kultivar Creole Sebagai  Substrat dalam Proses Produksi Siklodekstrin
Abstrak: Generally, starch is used as a food product and an industrial material. Because of its properties limitation, starch have to modified for larger usage. Cyclodextrin is a kind of modified starch produced in biochemical reaction by Cyclodextrin Glicosyl Transferase (CGTase). This research was used arrowroot cultivar creole as a substrate in production of cyclodextrin. Cyclodextrin is a non reducing oligosaccharide consisting of six, seven or eight glucose monomers arranged in a cyclic -shaped ring linked by á-1,4 D-glucopyranose rings. Production process of cyclodextrin consist of two steps. Hydrolize á-1,4 D-glucopyranose rings of amylose by á-amylase and catalysis of cyclodextrin by CGTase. The aim of the research was to determine the best concentration of á-amylase, CGTase, substrate usage and reaction time. The method of analysis was used iod method to analyze polysaccarides, DNS method to analyze reducing sugar and fenol method to analyze total sugar. The yield of arrowroot starch extraction is 9.81 percent. Starch was produced have a whiteness degree 75.06 percent BaSO 4. The proximate analysis result of starch are starch 90.22 percent, amylose 20.64 percent, amylopectin 79.32 percent, moisture 8.89 percent, ash 0.30 percent, fat 1.47 percent, fibre 0.96 percent, protein 0.30 percent. Gelatinization temperature of starch was at 69.5 – 82.5 0C. Temperature of liquification set on 82.5 – 85 0C. The best condition of liquification process was the use of á-amylase 0.5 percent mixed for 30 minutes and starch decreased until 5.26 g/L from the base substrate concentration 50 g/L. The best condition of cyclodextrin catalysis process was by using of CGTase 30 unit during 40 minutes and the cyclodextrin increased until 42 g/L by using the base substrate concentration 50 g/L.
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Judul: Design Process of Cyclodextrin Production from Sago (Metroxylon spp.) Starch
Abstrak: Luas lahan sagu Indonesia merupakan yang terbesar di dunia. Oleh karena itu, pengembangan produk berbasis pati sagu perlu digalakkan. Penelitian ini bertujuan untuk mendesain proses produksi siklodekstrin dari pati sagu dalam skala besar. Tahapan yang dilakukan terdiri dari pemilihan alternatif proses, penentuan alur proses, perhitungan neraca massa, pemilihan mesin dan peralatan, penjadwalan produksi, penentuan tata letak pabrik, serta analisis ekonomi. Produksi siklodekstrin diawali dengan mereaksikan 540 kg pati sagu yang disuspensikan dengan larutan penyangga asetat dan enzim CGTase menggunakan reaktor berpengaduk. Hasil reaksi dimurnikan dengan metode ultrafiltrasi dan nanofiltrasi, lalu dikeringkan dengan pengering semprot. Produk yang diperoleh adalah 289.76 kg siklodekstrin dengan kadar air 3%. Tiga siklus produksi dapat dilakukan secara parallel dalam satu hari, dengan total waktu kerja 9 jam. Tata letak bangunan produksi ditentukan dengan peta keterkaitan aktivitas dan penilaian kedekatan total. Luas bangunan produksi sebesar 463.94 m2, dengan luas tanah 804.00 m2. Desain proses produksi siklodekstrin dari pati sagu layak secara ekonomi, dengan NPV sebesar Rp2,171,946,961, net B/C sebesar 1.56, IRR sebesar 23.32%, dan periode pengembalian selama 5.88 tahun., Sago land area of Indonesia is the largest in the world. Therefore, the development of sago starch-based products needs to be encouraged. This study aims to design a large scale production process of cyclodextrin from sago starch. The stages of this study consist of selecting alternative processes, determining process flow, calculating mass balance, selecting machinery and equipments, scheduling production, determining plant layout, and economic analysis. Cyclodextrin production begins by reacting 540 kg of sago starch in acetate buffer solution and CGTase enzymes using a stirred tank reactor. The reaction result was purified by ultrafiltration and nanofiltration methods, then dried with spray dryer. The yield of this process is 289.76 kg of cyclodextrin with 3% of moisture content. Three production cycles per day can be carried out in parallel, with a total working time of 9 hours. Production building layout is determined by activity relationship chart and total closeness rating. Production building area is 463.94 m2, with land area of 804.00 m2. Cyclodextrin production process design is economically feasible, with Rp2,171,946,961 of NPV, 1.56 of net B/C, 23.32% of IRR, and 5.88 years of payback period.
Keyword: Cyclodextrin, Design process, Feasibility, Sago starch

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model