Judul: Sensitivitas gen sitokrom B (Cyt b) sebagai marka spesifik pada genus Rattus dan Mus untuk menjamin keamanan pangan produk asal daging
Abstrak: Appropriate techniques for detection and identification of origin of species for meat source are very important in the meat product processing to ensure the safety and halal foods. Multiplex PCR, in which many primers were used together for amplification of multiple target regions, is hopefully a suitable technique for meat sources identification. The aim of this study was to determine the specificity and sensitivity of the cytochrome b (cyt b) gene in rats as well as to design primers that can be used for detection of rat meat contamination in some processed meat products. The amplification of cyt b genes was done in seven species with different lengths of fragments which indicated specificity for cyt b genes sequences between species. The products showed specific DNA fragments of 157, 227, 274, 331, 398, 439 and 603 bp from goat, chicken, cattle, sheep, pig, horse and rat meats, respectively. Cyt b gene is sensitive as a specific marker with rats DNA that could be detected and be amplified with 100% success from as low as 1% level of contamination. Results showed that rat DNA in meatballs could be detected from 1% level contamination, otherwise rat DNA in meat floss could be detected from above 2.5% level contamination.
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Judul: Aplikasi Penggunaan Gen Sitokrom B Dengan Teknik Polymerase Chain Reaction (PCR) Sebagai Pendeteksi Campuran Daging Tikus Pada Produk Bakso
Abstrak: Polymerase chain reaction (PCR) technique was developed as a precise and quick method to identify meat species in both of raw meat and meat products. Rat primer has been developed from mitochondrial cytochrome b gene sequence. The aim of this study was to find out the ability and sensitivity level from this primer as contamination detector in meatball, and also to indentify the contamination of rat meats in meatball products which are sold in the Bogor City. Meatball samples were prepared from both mixtures rat meat and beef at different levels (1, 5, 10, 15, 20 and 25%) in meatball. As the result, rat’s meat could be identified start from 5% level and were amplified definitely at level contamination 15%. There were no rat meat found in the market samples or in other words, meatball sold in three big markets in Bogor City (Pasar Anyar, Pasar Bogor dan Pasar Jambu Dua) were free from rat contamination.
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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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