Judul: Metode Analisis Isolasi dan Identifikasi Salmonella Typhimurium pada Susu dengan Metode Real-Time PCR (Polymerase Chain Reaction)
Abstrak: Salmonella Typhimurium is one of pathogenic bacteria that cause foodborne disease. Conventional culture methods which is traditionally been considered as a ‘‘gold standards’’ are a common method to identified this pathogen. However, conventional culture methods are laborintensive and time-consuming. This study aimed to obtain a rapid and precise analytical method for Salmonella Typhimurium, to compare boiling method and commercial kit method using QIAamp® DNA Blood Mini Kit for extraction of DNA, identify and quantify Salmonella Typhimurium on sterilized milk using real-time PCR. Stages of this research are doing enrichment in pure culture and spiked sample, isolating the DNA of Salmonella Typhimurium by boiling method and commercial kit method, and then running a real-time PCR for determining specificity of the primers, determining primers concentration and doing quantification of Salmonella Typhimurium in sterilized milk. Commercial kit method produces DNA template purer than boiling method. So it affects their efficiency value. Commercial kit method assay has better efficiency than boiling method assay. It is 100% for commercial kit method and 386,8% for boiling method. The concentration of primers which is used in real-time PCR assay is 0.125 μM and its primers are specific for Salmonella Typhimurium. The result of Salmonella Typhimurium quantification in sterilize milk are not the same as quantification result from conventional method. But it has the same result with concentration value of Salmonella Typhimurium that is added to sterilize milk which is counted by Petroff-Hausser.
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Judul: Metode Analisis Isolasi dan Identifikasi Salmonella Typhimurium pada Susu  dengan Metode Real-Time PCR (Polymerase Chain Reaction)
Abstrak: Pengkuantifikasian Salmonella Typhimurium dalam susu UHT menggunakan real-time PCR menghasilkan konsentrasi yang berbeda satu log lebih besar dibandingkan dengan pengkuantifikasian menggunakan metode konvensional pada media XLDA, namun pengkuantifikasian dengan real-time PCR menghasilkan nilai konsentrasi yang sama dengan nilai konsentrasi Salmonella Typhimurium yang ditambahkan ke dalam susu UHT yang dihitung secara mikroskopi dengan petroff-hausser. Urutan sekuen oligonukleotida pada primer berpengaruh terhadap spesifisitas pengujian dengan menggunakan real-time PCR. Reverse dan forward primer yang digunakan memiliki spesifisitas yang baik terhadap Salmonella Typhimurium yang ditunjukkan dengan tidak teramplifikasinya Shigella sonnei sebagai bakteri non-target dan tidak terbentuknya primer-dimer pada pengujian. Konsentrasi primer yang sesuai pada pengujian ini adalah sebesar 0,125 µM baik untuk reverse primer maupun forward primer.
Keyword: real-time PCR, Salmonella Typhimurium, boiling method, QIAamp® DNA Blood Mini Kit, milk

Judul: Tree berdiameter lima adalah graceful
Abstrak: This manuscript presents some proofs that every tree of diameter five is graceful. A graceful tree is a graph which has a graceful labelling. This labelling assigns absolute difference of connected vertices, such that the resulting edge labels are mutually distinct. There are three theorems to be considered. First theorem proves that every tree of diameter four is graceful. Second theorem proves that every tree of diameter five is graceful or nearly graceful. The third theorem improves the second theorem and shows that every tree of diameter five is nearly graceful, which can be transformed into graceful using some certain patterns.
Keyword: Graf, Pelabelan graceful, Bogor Agricultural University, Institut Pertanian Bogor, IPB