Judul: Kandungan Kurkuminoid, Inhibisi a-Glukosidase dan Sitotoksisitas Ekstrak dari Beberapa Aksesi Kunyit (Curcuma domestica Val.)
Abstrak: Turmeric (Curcuma domestica Val.) is a medicinal plant family Zingiberaceae with curcuminoid content of the rhizome. This study aims to determine the content of curcuminoid, α-glucosidase inhibitory activity, and cytotoxicity test curcuminoids of turmeric extracts from several accessions. Curcuminoid content analysis was performed using HPLC. Inhibition of α- glucosidase performed in vitro with the substrate p-NPG. The cytotoxicity of curcuminoid extract of turmeric using BSLT method. The highest levels of curcuminoid owned by Ngawi, followed by Ciemas, Wonogiri, and Nagrak. Levels curcuminoids Ngawi of 24.50%. Turmeric extract the highest bioactivvity as α-glucosidase inhibitor activity is Nagrak accession with IC50 values of 207.093 μg/mL. Cytotoxycity test results showed that all samples have bioactivity and accession have the best LC50 value is Karanganyar at 19.090 μg/mL. Nagrak, Wonogiri, and Ngawi, has the potential to be developed into new varieties of turmeric with high bioactivity in inhibition α-glucosidase with IC50 moderate level.
Keyword: Bogor Agricultural University (IPB), turmeric, cytotoxicity, curcuminoids, α-glucosidase

Judul: Bioaktivitas Antioksidan dan Antiinflamasi Secara In Vitro serta Kandungan Kurkuminoid Temulawak dan Kunyit Asal Sukabumi
Abstrak: Curcuma xanthorrhiza and Curcuma domestica are kind of medicinal plants which have many health benefits. Both of them have curcuminoid content which is useful as an antioxidant and anti-inflamatory. In this study, ethanol extracts of C. xanthorrhiza and C. domestica promising lines from Sukabumi, Indonesia were investigated for the presence of curcuminoids, antioxidant and anti-inflamatory activities. HPLC method were used to determined curcuminoids content. The antioxidant (radical scavenging) potential of the samples was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical method. While for the anti-inflamatory activity, the in vitro cyclooxygenase 2 (COX2) inhibition method was used. The curcuminoid content of C. xanthorrhiza and C. domestica were 31.27 mg/g and 66.32 mg/g, respectively. IC50 values for DPPH radical scavenging activity were 81.99 μg/mL and 73.31 μg/mL, with C. domestica having lowest value and most potent than C. xanthorrhiza. Percent inhibition values for COX2 inhibitor activity were 74.84 % and 67.96 %, with C. domestica having the highest value. In this study, the ethanol extracts of C. domestica promosing line from Sukabumi of Indonesia exhibited most in curcuminoids content, antioxidants properties and anti-inflamatory activity than C. xanthorrhiza promosing line.
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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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