Judul: Potency of anting-anting (Acalypha indica) leaves extract as antibacterial toward streptococcus mutans and biofilm degradator on teeth
Abstrak: Tanaman anting-anting (Acalypha indica) biasa digunakan untuk mengobati disentri dan diare. Penelitian bertujuan menentukan potensi daun anting-anting sebagai antibakteri terhadap Streptococcus mutans dan degradator biofilm pada gigi. Ekstrak diperoleh dengan teknik maserasi menggunakan metanol, kloroform, dan n-heksana. Uji antibakteri dan degradasi biofilm dilakukan menggunakan teknik mikrodilusi dengan 96 well. Ekstrak n-heksana daun anting-anting memiliki potensi antibakteri paling baik dengan nilai konsentrasi hambat minimum dan konsentrasi bunuh minimum sebesar 500 μg/mL dan aktivitas degradasi biofilm yang cukup baik walau nilai IC50 belum dapat ditentukan hingga konsentrasi 200 μg/mL. Fraksi F3 hasil fraksinasi ekstrak n-heksana dengan kromatografi kolom merupakan degradator biofilm yang baik dengan nilai IC50 56.8 μg/mL. Alkaloid diduga sebagai senyawa aktif antibakteri dan degradator biofilm yang terdapat pada fraksi aktif., Anting-anting (Acalypha indica) plants is commonly used to treat dysentery and diarrhea. This research aims to determine potency of anting-anting as antibacterial toward Streptococcus mutans and biofilm degradator on teeth. Extracts was obtained by maseration technique using methanol, chloroform, and n-hexane. Antibacterial and biofilm degradation assays were performed using microdilution technique with 96 well. n-Hexane extracts of anting-anting leaves gave the best antibacterial potency with minimum inhibitory concentration and minimum bactericidal concentration value of 500 μg/mL and good biofilm degradation activity although the IC50 value could not be determined until 200 μg/mL. Fraction of F3 obtained from fractionation of n-hexane’s extract with column chromatography was good biofilm degradator with IC50 value of 56.82 μg/mL. Alkaloid was suggested as antibacterial and biofilm degradator in the active fraction. Keywords: alkaloid, antibacterial, anting-anting, biofilm degradator, Streptococcus mutans
Keyword: alkaloid, antibakteri, anting-anting, degradator biofilm, Streptococcus mutans

Judul: Aktivitas senyawa antibakteri akar tumbuhan anting-anting (Acalypha indica L.)
Abstrak: Anting-anting plants had been used by public traditionallly for curing various diseases like dysentry, diarrhea, malaria, and also as antibiotics. The research aimed to study the activity of compounds which had potential as antibactery in plant. The research was conducted activity of antibactery to Gram positif and negatif bacteria with four kinds bacteri are Staphylococus aureus, Bacillus subtilis, Escherichia coli dan Pseudomonas aeruginosa. The roots used were root extract from extraction of hexane solvent, ethyl acetate and methanol. The concentrations used was 200, 150, and 100 mg/ml for each solvents.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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