Judul: Immunostimulant Activity of Fish Oil from the Viscera of Gindara Fish, Gindara Kulit Duri, Layur, and Cucut
Abstrak: Minyak ikan menjadi sumber alami asam lemak tak jenuh (PUFA) omega-3 utamanya Docosahexaenoic acid (DHA) dan Eicosapentaenoic acid (EPA) yang diketahui mampu mengatur sistem imun dalam tubuh. Viscera dapat dijadikan alternatif bahan baku produksi minyak ikan guna meningkatkan nilai tambah Penelitian ini bertujuan untuk menentukan asam lemak yang terkandung pada viscera ikan air laut dalam serta potensi minyak ikan yang dihasilkan sebagai imunostimulan terhadap sel plenosit mencit secara in vitro. Ekstraksi minyak ikan air laut dalam dilakukan menggunakan metode bligh and dyer. Pengujian kapasitas proliferasi sel splenosit pada mencit dilakukan secara in vitro menggunakan pengujian MTT. Asam lemak paling dominan pada masing-masing viscera ikan air laut dalam antara lain asam palmitat pada viscera ikan layur dan ikan cucut, asam dokosaheksaenoat pada viscera ikan gindara, serta asam oleat pada viscera ikan gindara kulit duri. Minyak ikan air laut dalam yang digunakan dalam pengujian kapasitas proliferasi sel splenosit adalah minyak ikan gindara, minyak ikan gindara kulit duri, dan minyak ikan cucut. Keseluruhan sampel minyak ikan air laut dalam memiliki potensi sebagai agen imunostimulan., Fish oil is a natural source of omega-3 unsaturated fatty acids (PUFA), especially Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA), which are known to regulate the immune system in the body. Fish viscera can be used as an alternative raw material for fish oil production to increase added value. This study aims to determine the fatty acids contained in the viscera of deep sea fish and the potential of fish oil produced as an immunostimulant to plenocyte cells of mice in vitro. Extraction of deep sea fish oil was carried out using bligh and dyer method. Testing of the proliferative capacity of splenocytes in mice was carried out in vitro using the MTT assay. The most dominant fatty acids in each deep sea fish viscera include palmitic acid in the viscera of Layur and cucut fish, docosahexaenoic acid in gindara fish viscera, and oleic acid on the viscera of gindara fish with spines. The deep-sea fish oil used in testing the proliferative capacity of splenocyte cells were gindara fish oil, thorn skin gindara fish oil, and cucut fish oil. All samples of deep sea fish oil have potential as immunostimulant agents.
Keyword: asam lemak, concanavalin A, imunostimulan, minyak ikan

Judul: Ekstraksi Minyak Ikan dari Jeroan Ikan Air Laut serta Potensinya sebagai Imunostimulan
Abstrak: Minyak ikan diketahui memiliki kandungan omega-3 yang tinggi dan baik untuk kesehatan. Kandungan poly unsaturated fatty acids (PUFA) seperti omega-3 pada minyak ikan memiliki efek imunomodulator yang potensial. Penelitian ini bertujuan untuk mengetahui profil asam lemak serta potensi minyak ikan dari jeroan ikan air laut sebagai imunostimulan. Minyak ikan diekstraksi dari 7 jenis jeroan ikan air laut dengan metode bligh and dyer. Pengujian aktivitas imunostimulan dilakukan dengan melihat proliferasi sel splenosit mencit menggunakan metode MTT assay. Asam lemak dominan pada jeroan ikan bawal hitam, kakap merah, makarel, kembung dan selar kuning adalah asam palmitat, sedangkan asam lemak dominan pada jeroan ikan tongkol abu dan mahi-mahi adalah docosahexaenoic acid (DHA). Jeroan ikan makarel dan tongkol abu mengandung PUFA tertinggi sehingga digunakan pada pengujian aktivitas proliferasi sel splenosit. Hasil pengujian aktivitas proliferasi sel splenosit menunjukkan ekstrak kasar minyak jeroan ikan makarel dan tongkol abu dapat meningkatkan proliferasi sel splenosit sehingga berpotensi sebagai imunostimulan., Fish oil is known to have high omega-3 content and also good for health. The content of poly unsaturated fatty acids (PUFA) such as omega-3 in fish oil has a potential immunomodulatory effect. This study aims to determine the fatty acid profile and the potential of fish oil from the viscera of seawater fishes as an immunostimulant. Fish oil was extracted from 7 types of seawater fish viscera using the bligh and dyer method. Testing of immunostimulant activity was carried out by observing the proliferation of splenocyte cells of mice using the MTT assay method. The dominant fatty acid in black pomfret, red snapper, chub mackerel, indian mackerel and yellowstripe scad visceras were palmitic acid, while the dominant fatty acid in longtail tuna and dolphinfish visceras were docosahexaenoic acid (DHA). Chub mackerel and longtail tuna fish oil contained the highest PUFA, so they were used in testing the proliferative activity of splenocytes. The results of the splenocyte cell proliferation activity test showed that crude extract of chub mackerel and longtail tuna viscera fish oil increased the proliferation of splenocyte cells so that they have potential as immunostimulants.
Keyword: Immunostimulan, Minyak ikan, MTT assay, Omega-3, Splenosit

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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