Judul: Regulasi Tipe Impeler dan Laju Pengadukan Hidrolisis Enzimatik pada Minyak Ikan untuk Produksi Monoasilgliserol Omega 3
Abstrak: Enzymatic Hydrolyse of fish oil in omega-3 monoaxylglycerol estabilishment using stirred tank affected by impeller type and stirring speed. This study aims to determine the type of impeller and stirring speed to produce the highest rate of hydrolysis which affects on the production of omega 3. This research was objected to determine impeller type and stirring rate which were able to generate highest hydrolysis level in anaerobe stirred tank reactor. The other purpose was to explain relationship between hydrolysis level and omega–3 total yield. The reaction performance was applied in anaerobe condition with tank impeller put in center position. The result showed that using radial impeller would increase the hydrolyse reaction when the stirring speed increased. Use of axial impeller had hydrolyse reaction result higher than radial impeller but higher speed of axial impeller stirring would decreased the hydrolyse reaction because of damaged enzyme. The data showed that axial impeller gave the highest hydrolysis level in low stirring rate compared to radial impeller. The highest hydrolysis level was obtained in axial type was 64.32% in stirring rate of 500 rpm with reaction rate of 7.58 %, while in radial type was 63.81 % in stirring rate of 700 rpm reaction rate of 5.78 %. The Omega–3 fatty acid concentration in media brought reached was 3.20% by radial impeller, whereas by axial impeller was 2.70 %. Whole omega–3 total in media was eicosapentaenoic acid (EPA). Justified by GC-MS.
Keyword: stirred tank., omega–3, lipase, hydrolysis

Judul: Pengaruh Ratio Dt/Di dan Kecepatan Pengadukan terhadap Hidrolisis Enzimatik Minyak Ikan Lemuru Menggunakan Lipase Aspergillus Niger untuk Produksi Asam Lemak Omega-3
Abstrak: Lemuru is one of fish that found in Indonesia which can be processed into canned fish (sardine), cue, and fish meal. Fish oil is by- product of fish meal processing that is containing unsaturated fatty acid named omega-3, specially eicosapentanoic acid (EPA) and docosahexanoic acid (DHA). Research objectives are obtaining the optimum process conditions for enzymatic hydrolysis of lemuru fish oil using lipase from Aspergillus niger and determining the Dt/Di ratio and optimum stirring speed for enzymatic hydrolysis of fish oils produce omega-3 fatty acids.. Hexane added into 527,625ml of fish oil that have been rinsed by nitrogen and lipase enzyme that is dissolved with phosphat buffer 0,1 M and hydrolyzed at optimum condition for 48 hour. Product separated from water and analyzed with Gas Chromatography Mass Spectromerty. Scales that used in this research are 5, 10, 20, and 50, which each volumes are 52,7625 ml; 105,525 ml; 211,05 ml; and 527,625 ml. The product at last scale contain 1,16% EPA. DHA does not formed at this scale caused by non-ideal parameter. Stirring speed and ratio of stirrer diameter and container diameter are the parameters that influence production of omega-3. Ideal stirring speed using propeller with 3 blades calculated based on 250 rpm as initial stirring speed. Ideal ratio of container diameter and stirrer diameter is 1,1538.
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Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf