Judul: Potensi Pelepah Temulawak (Curcuma xanthorriza) sebagai Antikanker dan Antioksidan
Abstrak: The study aimed to evaluate the potency of temulawak (Curcuma xanthorrhiza) stem as anticancer by brine shrimp lethality test (BSLT) and antioxidant by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. The stem of temulawak midrib obtained from Bogor, was extracted by n-hexane, chloroform, ethyl acetate, methanol, and water, and the volatile oil was obtained by water distillation. The chloroform extract and volatile oil showed anticancer potency towards Artemia salina (LC50: 370.69 ± 22.69 μg mL-1 ; 123.05 ± 3.49 μg mL-1, respectively). Ethyl acetate and chloroform extracts had antioxidant activities (IC50: 46.41 ± 15.49 μg mL-1 and 52.72 ± 3.46 μg mL-1) but the activity did not as strong as ascorbic acid (control positive, IC50 1.80 ± 0.33 μg mL-1). The chloroform extract was further fractionated by column chromatography with Silica Gel G60F254-Merck as stationary phase and gradient of n-hexane, chloroform, and methanol as mobile phase. Antioxidant and anticancer potency of fraction which had antioxidant activity qualitatively were tested. The most antioxidant active fraction (F9) had anticancer potency (LC50: 522.95 ± 43.35 μg mL-1) and antioxidant activity (IC50: 79.57 ± 8.96 μg mL-1). In conclusion, F9 is potencial as an anticancer and antioxidant.
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Judul: Penapisan Senyawa Aktif Bunga dan Daun Temulawak (Curcuma xanthorrhiza) sebagai Antioksidan
Abstrak: This study aimed to screen antioxidant compounds on leaves and flower of C. xanthorrhiza using DPPH (2,2-diphenyl-1-picrylhydrazil) method. The flower and leaves were extracted with n-hexane, ethyl acetate, and methanol. Essential oil of the leaves was obtained through water distillation. Each extract and essential oil were determined for theirs antioxidant activities. The ethyl acetate extract of leaves had the best radical scavenging activity with IC50 41.50±7.80 μg/mL but not as good as ascorbic acid as the positive control with IC50 3.36±0.29 μg/mL. Fractionation performed on ethyl aceate leaves extract using silica gel column chromatography by step gradient elution with n-hexane, ethyl acetate, and methanol. Fractionation resulted 13 fractions (F1-F13) and the most active fraction was the F11 fraction (IC50 24.05±2.38 μg/mL). Fraction F11 was separated further by preparative thin layer chromatography and gave 8 fractions (F11.1-F11.8). Fractions F11.1 had the highest antioxidant activity with IC50 of 28.22±7.35 μg/mL. Phytochemical assay and infrared spectroscopy on F11.1 showed that the active compound as the antioxidant was flavonol. Keywords: C. xanthorrhiza, leaves, antioxidant, flavonol
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Judul: Model Input-output dalam Masalah Network Flow
Abstrak: Production process is a process, which is done by industry, to transform input into output. According to the type of output and its activity, industry can be classified into various sectors, which are connected to each other. Therefore, a model to analyze the connection among sections is needed. The model is known as input-output model (IO model). IO model presents an IO table, which shows informations about the transaction between goods and services in each economic sector. Furthermore, the IO model also shows that the amount of all input is the same as the amount of all output. In this paper, the transaction of each economic sector in IO table is analyzed using network flow theory. The formulated network flow problem implies that each sector represents partly as a producer and also as a consumer. This paper also solves a minimum cost circulation problem.
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