Judul: Literature Study of Hepatoprotective Temulawak Extract and Its Potential as Herbal Slimming Medicine
Abstrak: Ekstrak tanaman G. atroviridis dan K. angustifolia telah dilaporkan sebagai obat herbal pelangsing dengan mekanisme inhibisi lipase pankreas. Namun, mengonsumsi obat-obatan dapat memicu efek hepatotoksik. Oleh karena itu, penambahan senyawa hepatoprotektor perlu dilakukan untuk meningkatkan keamanan dalam konsumsi obat herbal. Studi literatur ini bertujuan menganalisis temulawak sebagai hepatoprotektor dengan parameter penurunan kadar SGOT dan SGPT yang terdeteksi dalam darah hewan uji yang diberi ekstrak temulawak dan menganalisis potensi temulawak sebagai obat herbal pelangsing dengan parameter daya inhibisi ekstrak temulawak terhadap enzim lipase. Pemberian ekstrak temulawak mampu menurunkan kadar SGOT dan SGPT pada hewan uji ayam dan tikus yang telah diberi perlakuan penambahan parasetamol. Ekstrak temulawak berpotensi sebagai obat herbal pelangsing karena mempunyai daya inhibisi lipase sebesar 80,50% yang mendekati kontrol positifnya sebesar 81,4%. Aktivitas inhibisi lipase ekstrak etilasetat rimpang temulawak lebih kecil dibandingkan ekstrak etanol buah asam gelugur namun lebih tinggi dari ekstrak air rimpang kunci pepet.
Keyword: Temulawak, hepatoprotektor, inhibisi lipase pankreas

Judul: Aktivitas Inhibisi Enzim α-Glukosidase dan Sitotoksisitas Ekstrak Kurkuminoid Rimpang Temulawak dari Berbagai Aksesi (In Vitro)
Abstrak: Temulawak (Curcuma xanthorriza Roxb.) is one of the Zingiberaceae family medicinal plants that grow in Indonesia. Temulawak rhizome contains curcuminoid which useful as an antidiabetic. This research aims to get temulawak accession with high capability of the inhibition activity of the α-glukosidase enzyme and it’s potential as a compound that toxic to shrimp’s larval Artemia salina Leach. Antidiabetic activity has been measured by formation of p-nitrophenol from enzymatc reaction of nitrophenil-α-D-glucopyranose (p-NPG) which is catalyze by α-glucosidase enzyme. The formation of p-nitrophenol was measured by spectrophotometer at λ=410 nm. The results of curcuminoid content and bioactivity assay (α-glukosidase enzyme inhibition and cytotoxicity) showed that the best accession of temulawak is Wonogiri’s accession. The value of curcuminoid content, IC50, LC50, from Wonogiri’s accession of temulawak rhizome extract, respectively for 85.19±4.64 mg/g, 333±22.52 μg/mL, and 82.78±7.70 μg/mL. Wonogiri’s accesion has the potential to be further researched and developed as a new variety.
Keyword: Bogor Agricultural University (IPB), cytotoxicity, curcuminoids, antidiabetic, Curcuma xanthooriza

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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