Judul: EkstraksiTaurin Alami dari Ikan Gindara (Lepidocybium flavobrunneum) sebagai Crude Taurine Powder
Abstrak: Escolar (Lepidocybium flavobrunneum) is one species of deep sea fish distributed in tropical seas, one of which in Southern Ocean of Java and Sumatra. Escolar contain taurine compounds that can improve the body's physiological functions . The aim of this study are to determine the optimum temperature and time extraction to produce the product, and to determine the characteristics of the crude taurine powder from the best extraction treatment. The samples of escolar fleshs were extracted using akuades 1:1 (m/v) with different treatment of temperature (30 , 45 , 60 , 75) °C and time (30 , 45 , 60 , 75) minute. The results showed that taurine content of escolar amount of 442,01 mg/kg , but after extraction, taurine levels increased. The highest levels of taurine in the products found in the extraction treatment at 45 °C for 45 minute with the increase of taurine level concentration 224,7%. The final product is called crude taurine powder which has the characteristics such as dry powder, the color is yellow and has a savory flavor. The chemical compositions were water content 10,16%, ash content 9,44%, protein content 76,91%, and fat content 3,48%
Keyword: taurine, deep sea fish, escolar, extraction, crude taurine powder

Judul: Virgin Deep Sea Fish Oil Lepidocybium flavobrunneum dan Ruvettus pretiosus serta Potensinya sebagai Imunostimulan
Abstrak: Ikan gindara dan gindara kulit duri merupakan ikan hasil tangkapan sampingan (by catch) dari ikan tuna yang dapat hidup pada kedalaman 200 meter dibawah permukaan air laut. Penelitian ini bertujuan menentukan nilai proksimat, rendemen minyak, profil asam lemak, parameter oksidasi dan potensi minyak ikan laut dalam sebagai agen imunostimulan secara in vitro. Ekstraksi minyak ikan laut dalam dilakukan dengan metode wet rendering suhu rendah (40, 50, 60, 70 ℃) dan pengujian proliferasi sel splenosit dengan uji MTT assay. Asam lemak yang dominan pada ikan gindara dan gindara kulit duri adalah asam oleat (C18:1n-9c) dengan nilai 26,85% (b/b) ikan gindara dan 23,02% (b/b) ikan gindara kulit duri. Minyak ikan gindara dan gindara kulit duri mengandung asam oleat yang tinggi. Hasil pengujian aktivitas proliferasi sel splenosit menunjukkan minyak ikan gindara dan gindara kulit duri suhu ekstraksi 70℃ dapat meningkatkan proliferasi sel splenosit sehingga berpotensi sebagai imunostimulan., Gindara and thorn skin gindara are by-catch fish from tuna which can live at a depth of 200 meters below sea level. This study aims to determine the proximate value, oil yield, fatty acid profile, oxidation parameters and the potential of deep sea fish oil as an immunostimulating agent in vitro. Extraction of deep sea fish oil was carried out using the low temperature wet rendering method (40,50,60,70℃) and splenocyte cell proliferation testing with the MTT assay test. The dominant fatty acid in gindara fish and thorn skin gindara was oleic acid (C18:1n-9c) with a value of 26.85% (w/w) for gindara fish and 23.02% (w/w) for gindara thorn fish. Gindara fish oil and gindara thorn skin contained high oleic acid. The results of testing the proliferative activity of splenocyte cells showed that gindara fish oil and gindara spines at an extraction temperature of 70℃ could increase splenocyte cell proliferation thus that they had the potential as immunostimulants.
Keyword: asam lemak, ikan laut dalam, imunostimulan

Judul: Bifurkasi Hopf pada Model Siklus Bisnis Kaldor Kalecki tanpa dan dengan Waktu Tunda
Abstrak: Business cycle model is one of dynamical system models in economic. One of the business cycles model is Kaldor-Kalecki model. Kaldor-Kalecki business cycle model that is written in delayed defferential equations, is a business cycle model that involves gross product and capital stock of a company. In this paper Kaldor-Kalecki business cycle model is analyzed using both nondelay and delay in time of capital stock. By Taylor expansion for the time delayed model, an analysis of stability around the fixed points has been done. Furthermore, by using Hopf bifurcation theorem, it can be shown that there exists periodic orbits and limit cycle. In the nondelayed model, changing the parameter of goods market could lead to the occurrence of Hopf bifurcation and the existence of limit cycle. Similarly, for the delayed model, it has been shown that changing the time delay parameter may result in the occurrence of Hopf bifurcation and limit cycle.
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