Judul: Isolasi dan Karakterisasi Senyawa Antibakteri Ekstra Daun Miana (Coleus scuatellariodes [L] Benth)
Abstrak: Miana is Lamianceae. It is commonly used as traditional medicine for infection and inflamation, cause by bacterial. The aim of this study to isolate and characterize ofantibacterial compound from miana leave extract. It is expected that the result will give information on characteristics and minimum inhibition concentration (MIC) of miana leave extract which have the highest antibacterial activity. The method of this research were extraction by Harborne method, antibacterial activity test by agar well diffution to staphylococcus aureus, staphylococcus epidermidis, Escherichia coli and Salmonella entereditidis and determination of MIC by dilution methode. The result showed that miana extract has the highest antibacterial activity on S. aureus and S. epidermidis. Miana extract was better than fresh and "infusan" miana leave on inhibition activity of S. aureus and S. epidermidis. MIC value of S. aureus and S. epidermidis were 3 mg/ml. The active fraction of maina leave extract contain phthalic acid derivates by GG-MS.
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Judul: Aktivitas Antifungi Ekstrak Daun Miana (Coleus scutellariodes [L] benth) pada Pertumbuhan Candida albicans Secara In Vitro
Abstrak: Miana (Coleus scuttellariodes [L] Benth) is one of the traditional medicine from family Lamiceae having flavonoids, tannins, saponins, steroids, and triterpenoids compound those can be used as antifungal. The objectives of this research were to examine the antifungal activity of Coleus scuttellariodes [L] Benth leaves extract against C. albicans and to analyze the active compounds in Coleus scuttellariodes [L] Benth leaves extract that has potential as an antifungal against C. albicans. The methods of this research were extraction with aquades, etanol 70%, and acetone, antifungal activity test by agar well diffusion and identification of active compound extract with the best inhibition in antifungal activity with Gas Chromatography-Mass Spectrometry (GC-MS). The result showed that acetone extract 400 mg/mL had the highest inhibition activity with the zone of 4.66 mm included in the low category, meanwhile aquades and etanol 70% extract did not show antifungal activity. Positive control nystatin concentration of 1.028 mg/mL is more effective in inhibiting of C. albicans. Minimum inhibition concentration value of acetone extract was 1.56 mg/mL. Identification of acetone extract with GC-MS result phytol in amount of 41.29%.
Keyword: Coleus scutellariodes, Candida albicans, antifungal

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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