Judul: Characterization of Chitin and Chitosan from Alam Crickets (Gryllus mitratus) from CV Alam Lestari Cibinong Animal Husbandry
Abstrak: Jangkrik memiliki eksoskeleton yang terdiri dari polisakarida struktural yang digunakan sebagai pelindung tubuhnya terutama bagian abdomen. Pemanfaatan jangkrik sebagai bahan pakan maupun pangan memiliki keterbatasan, hal ini disebabkan karena kandungan kitin yang cukup tinggi. Kitin merupakan komponen struktural yang membentuk eksoskeleton organisme insekta, fungi dan krustasea. Kitin tidak dapat larut dalam air, larutan basa pekat, larutan asam dan pelarut organik. Proses ekstraksi jangkrik menjadi kitin dibagi menjadi tiga tahap yaitu demineralisasi, deproteinisasi dan depigmentasi. Kitin dapat dimanfaatkan dengan cara mengubahnya menjadi kitosan. Kitosan merupakan polisakarida alami, tidak beracun, biokompatibel, ramah lingkungan dan bioadesif. Proses ekstraksi kitin menjadi kitosan diperlukan tahap deasetilasi. Penelitian ini bertujuan untuk mengkarakterisasi kitin dan kitosan sebagai hasil samping budidaya jangkrik alam (Gryllus mitratus). Variabel yang diamati adalah kitin dan kitosan yang dihasilkan dari jangkrik meliputi warna, bentuk partikel, kadar air, kadar abu, kadar nitrogen dan derajat deasetilasi. Hasil pengujian menunjukkan bahwa kitin yang dihasilkan memiliki bentuk partikel serpihan, berwarna putih, kadar air sebesar 9,74%, kadar abu sebesar 1,69%, kadar nitrogen sebesar 4,73% dan derajat deasetilasi sebesar 46,41%. Produk kitosan yang dihasilkan berbentuk serpihan, berwarna cokelat muda, kadar air sebesar 8,85%, kadar abu sebesar 1,35%, kadar nitrogen sebesar 4,25% dan derajat deasetilasi sebesar 94,69%. Hasil tersebut menunjukkan bahwa kitin dan kitosan yang dihasilkan dari jangkrik alam telah memenuhi SNI. Kata kunci: jangkrik alam, kitin, kitosan, Crickets have exoskeleton that consisting of polysaccharides of structural and used as a protective body especially the abdomen. The utilization of crickets as feed materials or food has its limitations, it is caused due to the content of chitin, which is quite high. Chitin is a structural component that forms the eksoskeleton organisms insects, fungi and crustaceans. Chitin can not be dissolved in water, the solution bases concentrated, acid solution and organic solvents. The process of extraction of crickets into chitin is divided into three stages: demineralization, deproteinisas and depigmentation. Chitin can be utilized by converting it into chitosan. Chitosan is a natural polysaccharide, non-toxic, biocompatible, environmentally friendly and bioadhesif. Extraction process of chitin into chitosan necessary stage deasetilasi. This study aims to characterize the chitin and chitosan as a result of the addition to the cultivation of crickets nature (Gryllus mitratus). The observed variable is the chitin and chitosan produced from crickets include color, particle shape, water content, ash content, nitrogen content and degree of deacetylation. The test results showed that the chitin produced has the form of flaky particles, white-colored, the moisture content amounted to 9,74%, ash content of 1,69%, the nitrogen content of of 4,73% and a degree of deacetylation of 46,41%. Products chitosan the resulting shaped flakes, coloured light brown, water content of 8,85%, ash content of 1,35%, the nitrogen content of 4,25% and a degree of deacetylation of 94,69%. These results indicate that the chitin and chitosan produced from crickets has fulfilled the SNI. Key words: alam crickets, chitin, chitosan
Keyword: alam crickets, chitin, chitosan

Judul: The Chitin Production Process from Shell of Crab Legs at CV. Bio Chitosan Indonesia
Abstrak: CV. Bio Chitosan Indonesia merupakan perusahaan yang mengolah cangkang udang dan kepiting salju (snow crab) menjadi kitin dan kitosan yang berkualitas tinggi. Penelitian ini dilakukan untuk menganalisis pengaruh konsentrasi HCl, waktu proses, dan suhu proses demineralisasi pada produksi kitin dari cangkang kaki rajungan di CV. Bio Chitosan Indonesia. Percobaan dilakukan melalui dua tahapan proses produksi kitin pada skala laboratorium menggunakan Rancangan Acak Lengkap Faktorial (RALF) dan Rancangan Acak Lengkap Single Factor (RALSF). Analisis ragam menunjukkan konsentrasi HCl, waktu proses demineralisasi, dan interaksi keduanya tidak berpengaruh nyata terhadap rendemen dan mutu kitin dari cangkang kaki rajungan, namun suhu proses demineralisasi berpengaruh nyata terhadap rendemen dan mutu kitin dari cangkang kaki rajungan. Perlakuan terbaik diperoleh dari kondisi proses produksi kitin dari cangkang kaki rajungan menggunakan larutan HCl 8%, waktu proses 3 jam, dan suhu ruang (30oC) dengan rendemen, kadar air, dan kadar abu masing – masing sebesar 20,44%, 3,36%, 0,33%. Kitin yang diperoleh sudah memenuhi standar mutu yang ditetapkan pembeli CV. Bio Chitosan Indonesia dan SNI., CV. Bio Chitosan Indonesia is a company engaged in processing shrimp and snow crab shells into high-quality chitin and chitosan. This research was conducted to analyze the influence of HCl concentration, process time, and demineralization process temperature on chitin production from shell of crab legs at CV. Bio Chitosan Indonesia. The experiment was carried out in two stages of chitin production at the laboratory scale using a Full Factorial Randomized Complete Design (FFRCD) and a Single Factor Randomized Complete Design (SFRCD). Analysis of variance showed that the concentration of HCl, demineralization process time, and their interaction did not significantly affect the yield and quality of chitin from the shell of crab legs. However, the demineralization process temperature significantly affected the yield and quality of chitin from the shell of crab legs. The best treatment was obtained from the chitin production process conditions from shell of crab legs using an 8% HCl solution, a process time of 3 hours, and room temperature (30°C), resulting in yields, moisture content, and ash content of 20.44%, 3.36%, and 0.33%, respectively. The obtained chitin meets the quality standards set by the buyers of CV. Bio Chitosan Indonesia and SNI.
Keyword: crab leg shell, demineralization, chitin

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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