Judul: Aktivitas Antifungi Ekstrak Daun Sirih Hijau (Piper betle L.) Terhadap Candida tropicalis
Abstrak: Betel leaf (Piper betle L.) is a medicinal plant that is widely used in treating various diseases, including vaginal candidiasis. One of the causes of this disease is Candida tropicalis. The aim of this study was to decide the effective concentration of the green betel leaf extract (Piper betle L.) as an anti-candidiasis (in vitro) against Candida tropicalis. Optimization of the effective concentration used the well diffusion method and analysis of the compounds used GC-MS. Green betel leaves were extracted using three solvents : water, ethanol 70%, and acetone. The percentage yield of acetone extract was greater than the water and the ethanol extracts, that was 19.64 %. From the result of phytochemical analysis, it was known that the acetone extract contains saponins, tannins, triterpenoids and steroids. Antibacterial activity test showed that all extracts have inhibitory effect on Candida tropicalis. Based on research data, acetone extract at 6.25 mg/mL is chosen as the effective concentration. The chemical components of green betel leaf acetone extract that have potential as anti-Candida tropicalis were benzoic acid; 2-hexadecen-1-ol, 3,7,11,15-tetramethyl and neophytadiene.
Keyword: Anti-candidiasis, Candida tropicalis, Piper betle L.

Judul: Aktivitas penghambatan Candida albicans oleh ekstrak daun sirih hijau (Piper betle, Linn)
Abstrak: Green betel leaf is knowed as disinfectant and able to inhibit bacterial and fungi. The last research showed that green betel leaf extract by aquadest and ethanol had inhibitory activity of C. albicans. The aims of this research was to measure of inhibitory activity of C. albicans from green betel leaf extract in vitro and the Minimum of Inhibitory Concentrtation (MIC) with to decide bioactive compounds that inhibit C. albicans. This study used green betel leaf extracted by aquadest, 70 % ethanol, and acetone. The concentration of each extract used from 25, 50, 100, 200, 400 mg/mL and showed that the optimum activity occurred on the acetone extract at a concentration of 400 mg/mL with diameter of inhibition 23.483 mm and at MIC 12,5 mg/mL with diameter of inhibition 1.742 mm. Statistical analysis the difference solvents and variation of concentration showed significant effect on diameter of inhibition. Acetone extract was analyzed by Pyrolysis GC-MS and produced inhibitor compounds namely derivative of benzoic acid, phenol, and eicosene.
Keyword: green betel leaf extract, C. albicans, antifungal

Judul: Dinamika Sistem Ekonomi dengan Model Overlapping-Generation
Abstrak: This manuscript describes a modern macroeconomic model in discrete time so-called Overlapping-Generation Model. In general, modeling framework of Overlapping-Generation is assumed that each person lives for only two periods, i.e. he/she works in the first period and retires in the second. By maximizing lifetime utility, which depends on consumption in the two periods of life, there will exist a steady state condition. Steady state happens when capital per capita at the first and the second periods are equal. In the end, economics converges to a steady state. Some numerical simulations show the effects of some parameters to the steady state condition.
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