Judul: Inhibition of Vibrio parahaemolyticus Bacteria Growth Using Bacteriophages Isolated from Shrimp Farming Water in Tasikmalaya District
Abstrak: Penyakit yang disebabkan oleh bakteri Vibrio diantaranya adalah penyakit vibriosis dan acute hepatopancreatic necrosis disease (AHPND) yang menyerang komoditas udang dalam budidaya. Penggunaan antibiotik tertentu sudah dilarang dalam praktik budidaya sehingga kedepannya diperlukan alternatif pengobatan penyakit bakterial yang ramah lingkungan. Bakteriofag merupakan virus yang menginfeksi dan bereplikasi di dalam sel bakteri. Bakteriofag tipe litik dapat menyebabkan kematian bakteri targetnya. Penelitian ini bertujuan untuk mendapatkan isolat bakteriofag dari air budidaya udang di Kabupaten Tasikmalaya yang dapat menghambat pertumbuhan bakteri patogen Vibrio parahaemolyticus. Perlakuan pada penelitian ini yaitu kontrol negatif (K-), kontrol positif (K+), isolat bakteriofag Tasikmalaya (FT), dan antibiotik tetracycline (TC). Isolat bakteriofag berhasil diisolasi dari sumber air budidaya udang di Kabupaten Tasikmalaya. Bakteriofag menunjukan aktivitas litik terhadap bakteri patogen V. parahaemolyticus, ditunjukkan dengan terbentuknya plak bening pada permukaan media agar. Isolat bakteriofag Tasikmalaya dengan konsentrasi 103 PFU mL-1 mampu menghambat pertumbuhan bakteri V. parahaemolyticus secara in vitro, yaitu perlakuan FT menekan kepadatan bakteri sebesar 11,52% dari perlakuan K+. Adapun secara in vivo menggunakan hewan model Artemia yaitu mendapatkan nilai survival rate 91,11±1,57% pada perlakuan FT dan berbeda nyata dengan perlakuan K+ yang hanya 67,78±6,85%., Diseases caused by Vibrio bacteria include vibriosis and acute hepatopancreatic necrosis disease (AHPND) which attack shrimp commodities in aquaculture. The use of certain antibiotics has been prohibited in aquaculture practices so that in the future, alternative treatments that are environmentally friendly against bacterial diseases are needed. Bacteriophages are viruses that infect and replicate within bacterial cells. The lytic type bacteriophage can cause the death of the target bacteria. This study aims to obtain bacteriophage isolates from shrimp farming water in Tasikmalaya District which can inhibit the growth of the pathogenic bacterium Vibrio parahaemolyticus. The treatments in this study were negative control (K-), positive control (K+), Tasikmalaya bacteriophage isolate (FT), and tetracycline antibiotics (TC). Bacteriophage isolates were isolated from water sources in shrimp ponds in Tasikmalaya District. Bacteriophages showed lytic activity against the pathogenic bacterium V. parahaemolyticus, indicated by the formation of clear plaques on the surface of the agar medium. Tasikmalaya bacteriophage isolate with a concentration of 103 PFU mL-1 was able to inhibit the growth of V. parahaemolyticus bacteria in vitro, namely FT treatment suppressed bacterial density by 11,52% against K+ treatment. Artemia animal model in vivo obtained a survival rate of 91,11±1,57% in the FT treatment and significantly different from the K+ treatment which was only 67,78±6,85%.
Keyword: Artemia, bacteria, bacteriophages, lytic, Vibrio parahaemolyticus

Judul: Bakteriofag Tipe Litik untuk Vibrio parahaemolyticus yang Diisolasi dari Air Kerangkeng Lobster di Jakarta Utara.
Abstrak: Vibrio parahaemolyticus merupakan bakteri Gram negatif yang secara alami lingkungan hidupnya terdapat di ekosistem laut. Penggunaan antibiotik mengakibatkan resistansi terhadap sebagian besar bakteri termasuk bakteri V. parahaemolyticus. Salah satu cara yang dikembangkan ialah virus bakteri yang digunakan sebagai terapi atau biasa dikenal dengan bakteriofag. Bakteriofag dapat menghambat pertumbuhan bakteri resistan antibiotik dengan sifat spesifik yang tinggi. Penelitian ini bertujuan untuk mendapatkan isolat bakteriofag dari air kerangkeng lobster di Jakarta Utara yang dapat menghambat pertumbuhan bakteri patogen Vibrio parahaemolyticus. Terdapat lima tahapan yang dilakukan dalam penelitian ini, yaitu: identifikasi dan karakterisasi bakteri V. parahaemolyticus, isolasi bakteriofag dan uji plaque assay, purifikasi bakteriofag, uji penghambatan pertumbuhan bakteri V. parahaemolyticus secara in vitro, dan uji penghambatan pertumbuhan bakteri V. parahaemolyticus secara in vivo. Pada penelitian ini memakai empat perlakuan, yaitu SM buffer (K-), bakteri V. parahaemolyticus (K+), isolat bakteriofag Jakarta Utara (FJ), dan antibiotik tetrasiklina (AB). Pada media agar terbentuk zona bening, yang memperlihatkan bahwa bakteriofag menandakan aktivitas litik terhadap bakteri V. parahaemolyticus. Dengan konsentrasi 10-3 PFU mL-1 isolat bakteriofag Jakarta Utara dapat menghambat pertumbuhan bakteri V. parahaemolyticus secara in vitro pada pengamatan jam ke-24 menghambat pertumbuhan bakteri sebesar 9,8% dari perlakuan K+. Pada perlakuan FJ secara in vivo menggunakan artemia sebagai hewan uji coba didapatkan nilai tingkat kelangsungan hidup sebesar 91,11±3,14% dan berbeda nyata dengan perlakuan K+ dengan nilai tingkat kelangsungan hidup sebesar 68,89±1,57%., Vibrio parahaemolyticus is a Gram negative bacterium that naturally lives in marine ecosystems. The use of antibiotics resulted in resistance to most bacteria including V. parahaemolyticus. One of the methods developed is a bacterial virus that is used as a therapy or commonly known as a bacteriophage. Bacteriophages can inhibit the growth of antibiotic-resistant bacteria with high specificity. This study aims to obtain bacteriophage isolates from lobster cage water in North Jakarta which can inhibit the growth of the pathogenic bacterium V. parahaemolyticus. There were five stages carried out in this study, namely: identification and characterization of V. parahaemolyticus bacteria, bacteriophage isolation and plaque assay test, bacteriophage purification, in vitro bacterial growth inhibition test of V. parahaemolyticus, and in vivo bacterial growth inhibition test of V. parahaemolyticus. In this study, four treatments were used, namely SM buffer (K-), V. parahaemolyticus bacteria (K+), North Jakarta bacteriophage isolate (FJ), and tetracycline antibiotic (AB). On the agar medium a clear zone was formed, this indicated that the bacteriophage indicated lytic activity against V. parahaemolyticus bacteria. With a concentration of 10-3 PFU mL-1, North Jakarta bacteriophage isolate could inhibit the growth of V. parahaemolyticus bacteria in vitro at 24 hours of observation, inhibiting the growth of bacteria by 9.8% from the K+ treatment. In the in vivo FJ treatment using artemia as a test animal, the survival rate was 91.11±3.14% and significantly different from the K+ treatment with a survival rate of 68.89±1.57%.
Keyword: antibiotic, bacteria, bacteriophage, resistant, Vibrio parahaemolyticus

Judul: : Persamaan Tunggal sebagai Representasi Kurva Komposit
Abstrak: A mathematical method is introduced to represent a composite curve based on an extension of analytic geometry. The representation is given either with a single equation or with two equations, in the case of parametric representation. This method permits the representation of composite curves in similar manner to the conventional representation of non-composite curves. Some mathematical tools, including Heaviside unit step function and periodizer function, are used in the establishment of a single equation. In this paper, regular equations of regular and irregular polygon, as well as composite curves of two dimensions, are implemented using a computer algebraic system, Mathematica.
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