Judul: Phisycal Characteristic and Power of Mannanase Enzim of Palm Kernel Meal
Abstrak: Di Indonesia, perkebunan kelapa sawit terus meningkat dengan perkiraaan total luas areal kelapa sawit sebesar 7 824 623 ha (Dirjen Perkebunan, 2010). Pembuatan minyak sawit (Crude Palm Oil, CPO) menghasilkan hasil samping berupa bungkil inti sawit (Palm Kernel Meal). Kendala utama pemberian bungkil inti sawit pada unggas adalah tingginya kandungan karbohidrat sukar larut yaitu mannan. Pengayakan dan perlakuan enzimatis merupakan metode yang digunakan saat ini dalam menangani permasalahan pada bungkil inti sawit. Pemberian enzim penghidrolisis serat pada bungkil inti sawit dapat meningkatkan kualitas bungkil inti sawit (Handoko, 2010). Penelitian ini mengkaji sifat fisik produk bungkil inti sawit hasil ayakan dengan ukuran ayakan berbeda serta mengkaji kinerja enzim pada bungkil inti sawit hasil ayakan terbanyak. Perlakuan uji fisik dilakukan masing-masing tiga ulangan untuk menguji sifat fisik bungkil inti sawit giling berdasarkan empat jenis ukuran ayakan (mesh 16, mesh 30, mesh 50, mesh 100). Peubah yang diamati adalah berat jenis, daya ambang, kerapatan tumpukan, kerapatan pemadatan tumpukan, sudut tumpukan, derajat keasaman dan kelarutan total. Produk bungkil inti sawit dari mesh 30 kemudian ditambahkan enzim sebagai perlakuan dengan tiga ulangan yaitu pemberian enzim mannan komersial 0,1mL/gram BIS (setara dengan 919,27x106 U/liter), enzim cairan rumen 0,1mL/gram BIS (0,013x106 U/liter enzim cairan rumen) dan kontrol. Hasil penelitian menunjukkan bahwa perlakuan ayakan pada bungkil inti sawit sangat nyata (P<0,01) mempengaruhi berat jenis, sudut tumpukan, daya ambang, kerapatan tumpukan dan kerapatan pemadatan tumpukan. Nilai kerapatan tumpukan, kerapatan pemadatan tumpukan, berat jenis bungkil inti sawit menurun seiring dengan menurunnya diameter lubang ayakan, sebaliknya sudut tumpukan dan daya ambang bungkil inti sawit meningkat seiring menurunnya diameter lubang ayakan. Pemberian enzim mannanase komersial dan pemberian enzim cairan rumen nyata (P<0,05) mempengaruhi peningkatan gula pereduksi dari 4,806 mg/g menjadi 10,516 mg/g (meningkat sebesar 118,8%) dan 5,921 mg/g (meningkat sebesar 23,2%). Peningkatan gula pereduksi mengindikasikan adanya peningkatan karbohidrat sukar larut yang dapat dipecah. Penambahan enzim cairan rumen meningkatkan total gula pereduksi produk bungkil inti sawit mesh 30 sebesar 23,2% meskipun memiliki aktivitas enzim mannanase yang lebih rendah dibanding dengan aktivitas enzim mannanase komersial.
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Judul: Isolasi dan Pencirian Bakteri Mananolitik Pendegradasi Bungkil Inti Sawit
Abstrak: Mannanase is an enzyme which can be utilized in food and feed sector. This research is aimed to isolate and characterize the mannanase producing soil bacteria from palm plantations in Cikasungka, Bogor, and to know the ability of manannase in hydrolyzing palm kernel cake (PKC) substrate become to manno-oligosaccharide (MOS). There were 8 isolates isolated from the soil of Cikasungka Plantation, Bogor. Three isolates were choosen with the highest mannanolytic index to be further characterized. Isolate 5 produced the highest mannanase activity at 18 h of incubation (0.039 U/mL) and 54 h (0.051 U/mL). Isolate 6 produced the highest mannanase activity at 30 h of incubation (0.041 U/mL) and 66 h (0.058 U/mL). Isolate 7 produced the highest mannanase activity at 24 h of incubation (0.041 U/mL). The specific activity of isolate 5, 6 and 7 had value 2-3 times higher than their own enzymatic activity. One selected isolate, isolate 6 had optimum activity in pH 5.5 at 30 °C and pH 7 at 40 °C. The enzyme stability of isolate 6 were decreasing at the both pH and temperature optimum. The polimerization degree of isolate 6 in pH 5.5 at 30 °C had value of 4.0-4.1 and 6.9-7.5 in pH 7 at 40 °C. Isolate 6 posseses high degree of polimerization in MOS production, it is potentially used as cattle prebiotic.
Keyword: mannanase, mannanolytic, manno-oligosaccharide, palm kernel cake, polimerization degree

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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