Judul: Penentuan Kuersetin dalam Bawang Dayak (Eleutherine palmifolia) dengan Kromatografi Cair Kinerja Tinggi
Abstrak: Eleutherine palmifolia known as bawang dayak or bawang sabrang is widely used as herbal medicine to treat various diseases, including diabetes, hypertension and lowering cholesterol. The objectives of this research are to determine content of quercetin in bawang dayak and to analyze the performance of determination method of quercetin in bawang dayak using high-performance liquid chromatography (HPLC). To ensure that HPLC method can be used for the intended purpose then the method has to be validated. Parameters determined on method validation were linearity, limit of detection, limit of quantification, and precision. The linearity in the concentrations of 0.5, 2.5, 10, and 20 mg/L showed correlation coefficient of 0.9992. The limit of detection was 0.0482 mg/L and the limit of quantification was 0.1460 mg/L. The precision of this method was 13.41%. The average concentration quercetin in bawang dayak was 0.2943%. The number of quercetin that is high enough make bawang dayak potential as a medicine.
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Judul: Antioxidants and Antidiabetic Potency of Aqueous and Ethanolic Extracts of Bawang Dayak Bulbs (Eleutherine palmifolia) in vitro and in vivo.
Abstrak: Eleutherine palmifolia is an indigenous plant from Kalimantan and is widely used by the Dayak tribes to cure several diseases including diabetes mellitus. The purpose of this research is to scientifically prove antioxidant and antidiabetic properties of bawang dayak bulbs and to evaluate its safety that can be used as a source of functional food. Bawang dayak bulbs (BDB) were extracted with water and ethanol solvents. The solutions which contain the aqueous and the ethanolic extracts then freeze dryed. Phytochemical screening that was conducted upon aqueous and ethanolic extracts showed that both of extracts contained alkaloids, tannins, phenolics, flavonoids, triterpenoids, and steroids. Prominent types of phytochemical compounds in aqueous extracts are alkaloids phenolic and triterpenoids, whereas in the ethanolic extract are alkaloid, tannin, phenolic, flavonoids and triterpenoids. Both types of extracts showed antioxidant activity and alpha glucosidase inhibition activity. The antioxidant activity of the ethanolic extract is very significantly higher (P<0.01) than that of the aqueous extract, with IC50 112 ppm for ethanolic extract and 526 ppm for aqueous extract. Alpha glucosidase inhibition activity of ethanolic extract was also very significantly greater (P<0.01) than that of the aqueous extract, with IC50 241 for ethanolic extract and 505 ppm for aqueous extract. The result of NMR (Nuclear Magnetic Spectroscopy) analysis showed that there were eleutherinoside A, eleutherol, and eleuthoside B in ethanolic extract of BDB, but there was not enough sinyal in NMR spectra of aqueous extract to conduct NMR-J resolved data analysis. According to Ieyama et al. (2011) those compounds showed alpha glucosidase inhibitory activity, and eleutherinoside has the biggest activity with IC50 0.5 mM. So it is suggested that eleutherinoside A, eleutherol and eleuthoside B are the active compounds of alpha glucosidase inhibitory activity in BDB ethanolic extract. It is also suggested that alphaglucosidase inhibitory capacity in BDB aqueous extract was presented by the activities of phenolic, alkaloid and triterpenes compounds. Oral glucose tolerance test (OGTT) was done to decide the dose of bawang dayak extracts for in vivo analysis in diabetic experimental rats. The chosen dose was 100 mg/kg BW to diabetic rats, whereas a higher dose was chosen for nondiabetic rats (500 mg/kg BW). The reason of higher dose implementation to non diabetic rats is to evaluate the safety of aqueous and ethanolic extracts to the function and morphology of liver and kidney organs. Sprague-Dawley (SD) male rats age ± 8 weeks old and weighs ± 180 grams were used in this experiment. Conditions of diabetes mellitus (DM) is obtained by induction of 110 mg/kg BW of alloxan monohydrate to SD rats intraperitoneally. BDB aqueous and ethanolic extracts were administered orally by gavage to diabetic and non-diabetic rats for 28 days. Termination was done by using ketamine on day 29 and followed by blood, liver, kidneys and pancreas collections. Observations and analysis were conducted on the body weight, blood glucose levels, serum insulin levels, blood lipid profile (total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides), serum catalase and superoxide dismutase (SOD) enzymes activities, liver malonaldehyde levels, serum creatinine levels, serum albumin levels, Serum Glutamic-Piruvic Transaminase (SGPT) and Serum Glutamic-Oxaloacetic Transaminase (SGOT)
Keyword: diabetes, bawang dayak, Eleutherine palmifolia, antioxidant, functional food

Judul: Dynamics Model for Rural and Urban Economic Growth
Abstrak: Lewis theory of structural change has focused on mechanisms that allow countries to transform their domestic economic structure to a more modern economy. The proposed model deals with the mechanism of interaction between rural and urban Economic. This model is concerned with the process of labor transfer from rural to urban areas. This study aims to model the dynamics of economic growth in rural and urban areas, including determining the equilibrium solution and to carry out simulation of the model. The simulation results show that the transfer of labor from rural to urban areas will increase the rate of change of capital so that structural changes can be realized. In addition, increased propensity to save in rural areas will also accelerate structural change
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