Judul: Lactobacillus plantarum (SK5) sebagai Biopreservatif pada Fillet Ikan Kakap (Skinless) selama Penyimpanan Suhu Chilling
Abstrak: The sources of biopreservative can be found in lactic acid bacteria (LAB) such as bacteriocin, H2O2 and organic acid that can inhibit pathogen and spoilage bacteria growth. This study aimed to compare utilization biopreservative (biomass and supernatant) of Lactobacillus plantarum (SK5) and formaldehyde for preservatif of snapper fillet. The treatments of this study were red snapper fillets were administered biomass (B) 12 mL/100 g, soaked supernatant (S) and formaldehyde 4% 60 mL/100 g (F) for 10 minutes and fillet without addition (K-). All of fillets were stored at chilling temperature for 11 days and analyzed of Total Volatile Base (TVB), pH, total of aerobic microbial and total of LAB on 0, 2, 4, 7, 9 and 11 days. Supernatant utilization was the best treatment for preservation of red snapper fillet. TVB value of S fillet still had a low value (<30 mg N/100g) until the 11 days. Its value is not significantly different from the F fillet (p<0.05). Supernatant from cultivation media of L. plantarum (SK5) can be used as a biopreservative for snapper fillets at chilling temperature and it can replace formaldehyde when viewed from the parameters of TVB.
Keyword: Bogor Agricultural University (IPB), L. plantarum (SK5), formaldehyde, fillet, chilling, biopreservative

Judul: Application of Lactobacillus rhamnosus IN13 and Lactobacillus plantarum IN05 on Catfish (Pangasius sp.) polluted by Listeria monocytogenes
Abstrak: Bakteri Asam Laktat (BAL) merupakan bakteri non patogen yang aman bagi manusia dan berpotensi sebagai biopreservatif karena dikategorikan sebagai generally recognized as safe (GRAS). Beberapa produk metabolisme yang dihasilkan oleh BAL memiliki kemampuan sebagai antimikrob ialah asam organik, hidrogen peroksida, diasetil dan bakteriosin. Senyawa antimikrob L. plantarum IN05 dan L. rhamnosus IN13 yang diisolasi dari makanan fermentasi inasua dikaji potensinya sebagai biopreservatif. Kebutuhan konsumsi ikan segar di masyarakat banyak diminati karena kandungan protein hewani yang tinggi. Ikan patin merupakan salah satu ikan yang banyak dikonsumsi masyarakat, namun memiliki kekurangan mudah mengalami kerusakan dan penurunan mutu. Hal ini disebabkan oleh L. monocytogenes yang memiliki kemampuan tumbuh pada suhu penyimpanan dingin (refrigerasi) bahkan mampu bertahan pada suhu penyimpanan beku. Penelitian ini bertujuan untuk mengaplikasikan dan membandingkan penggunaan senyawa antibakteri (supernatan bebas sel netral, supernatan bebas sel, dan biomassa sel bakteri) dari isolat L. rhamnosus IN13 dan L. plantarum IN05 serta formalin dalam penyimpanan ikan patin fillet yang terkontaminasi bakteri Listeria monocytogenes. Metode yang digunakan mencakup produksi senyawa antibakteri, penentuan sensitivitas senyawa antibakteri terhadap bakteri uji, uji konfirmasi senyawa antibakteri dengan penambahan proteinase K, aplikasi senyawa antibakteri pada ikan patin fillet, perhitungan total koloni bakteri, koloni bakteri L. monocytogenes, dan bakteri asam laktat, serta pengukuran nilai pH ikan patin fillet. Senyawa antimikrob SBSN dari L. rhamnosus IN13 memiliki kemampuan mempertahankan ikan patin fillet sampai lama penyimpanan 14 hari sesuai dengan syarat ikan segar yang layak untuk dikonsumsi. Nilai total mikrob 5.65 log CFU/g, nilai pH daging ikan patin fillet 6.37, dan nilai total bakteri L. monocytigenes yang menurun selama waktu penyimpanan., Lactic Acid Bacteria (LAB) are non-pathogenic bacteria that are safe for humans and have potential as biopreservatives because they are categorized as generally recognized as safe (GRAS). Several metabolic products produced by LAB have antimicrobial properties, namely organic acids, hydrogen peroxide, diacetyl and bacteriocins. Antimicrobial compounds L. plantarum IN05 and L. rhamnosus IN13 isolated from fermented inasua food were studied for their potential as biopreservatives. The need for consumption of fresh fish in the community is in great demand because of the high content of animal protein. Catfish is one of the fish that is widely consumed by the community, but it has the disadvantage of being easily damaged and decreasing in quality. This is due to L. monocytogenes which has the ability to grow at cold storage temperatures (refrigeration) and even survive at frozen storage temperatures. This study aims to apply and compare the use of antibacterial compounds (neutral cell-free supernatant, cell-free supernatant, and bacterial cell biomass) from L. rhamnosus IN13 and L. plantarum IN05 isolates and formalin in storage of catfish fillets contaminated with Listeria monocytogenes bacteria. The methods used include the production of antibacterial compounds, determination of the sensitivity of antibacterial compounds to test bacteria, confirmation test of antibacterial compounds with the addition of proteinase K, application of antibacterial compounds to catfish fillets, calculation of total bacterial colonies, bacterial colonies of L. monocytogenes, and lactic acid bacteria, as well as measurement of the pH value of catfish fillet. The SBSN antimicrobial compound from L. rhamnosus IN13 has the ability to maintain
Keyword: Bacteriocin, Biopreservatives, Lactobacillus rhamnosus, Listeria monocytogenes, pangas-catfish fillets

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh.
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. ,,,
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular.