Judul: Bioextraction of Chitin from Vaname Shrimp Waste (Litopenaeus vannamei) Using Lactic Acid Bacteria
Abstrak: Industri pembekuan udang menghasilkan banyak karapas berupa kulit dan kepala udang. Hasil samping pengolahan udang dapat diolah lebih lanjut menjadi kitin. Kitin dapat diekstraksi menggunakan metode kimia dan biologis. Penelitian ini bertujuan menentukan pengaruh lama fermentasi berbeda pada ekstraksi kitin dari karapas kulit dan kepala udang secara biologis menggunakan starter campuran bakteri L. plantarum SK (5), L. plantarum NS (9) dan P. pentosaceus BP (20). Kitin diperoleh melalui proses fermentasi. Fermentasi dilakukan selama 5, 10 dan 15 hari. Kadar protein dan kadar abu diamati pada 5, 10 dan 15 hari. Analisis gugus fungsi FTIR dilakukan pada hari ke 15 fermentasi. Ekstraksi kitin karapas udang menggunakan bakteri asam laktat menghasilkan kitin dengan derajat deproteinasi sebesar 31,29% dan derajat deasetilasi sebesar 36%. Ketiga isolat BAL (L. plantarum SK(5), L. plantarum NS(9) dan P. pentosaceus BP(20)) dapat digunakan dalam proses bioekstraksi kitin karapas udang dengan fungsi utama untuk deproteinasi., The shrimp freezing industry produces a lot of carapace in the form of shells and heads of shrimp. The by-product of shrimp processing can be further processed in the form of chitin. Chitin can be extracted using chemical and biological methods. This study aims to determine the effect of different fermentation times on the biological extraction of chitin from shell carapace and shrimp heads using a mixed starter of L. plantarum SK (5), L. plantarum NS (9) and P. pentosaceus BP (20) bacterial starter. Chitin is obtained by bio-extraction method through a fermentation process. Fermentation was carried out for 5, 10 and 15 days. Protein content and ash content were observed at 5, 10 and 15 days. FTIR analysis was performed on the 15th day of fermentation. Extraction of shrimp carapace chitin using lactic acid bacteria produced chitin with a degree of deproteination of 31.29% and a degree of deacetylation of 36%. The three LAB isolates (L. plantarum SK(5), L. plantarum NS(9) and P. pentosaceus BP(20)) can be used in the bioextraction process of shrimp carapace chitin with the main function of deproteination.
Keyword: chitin, fermentation, lactic acid bacteria, starter bacteria

Judul: Characteristics of Fermented Shrimp Carapace Hydrolyzate using a Lactic Acid Bacteria Starter from Bekasam
Abstrak: Karapas udang merupakan hasil samping dari industri pengolahan udang yang berpotensi dimanfaatkan menjadi produk bernilai tambah diantaranya adalah kitin dan hidrolisat melalui proses fermentasi. Penelitian ini bertujuan menentukan pengaruh lama fermentasi yang berbeda terhadap karakteristik mikrobiologis dan kimiawi serta profil asam amino dan astaxanthin pada hidrolisat karapas udang terpilih. Bubuk karapas udang sebanyak 10 gram ditambah 6,5% (b/b) glukosa, 100 mL akuades, dan 10% (v/b) starter campuran tiga jenis isolat BAL (Lactobacillus plantarum SK(5), Lactobacillus plantarum NS(9), dan Pediococcus pentosaceus BP(20)) kemudian difermentasi. Rancangan percobaan yang digunakan yaitu Rancangan Acak Lengkap dengan faktor lama fermentasi (5, 10 dan 15 hari) terhadap nilai pH, total asam tertitrasi (TAT), Total bakteri asam laktat (BAL), kadar kalsium, dan protein. Perlakuan terpilih selanjutnya dianalisis asam amino dan astaxanthin. Lama fermentasi yang berbeda memberikan pengaruh nyata terhadap total bakteri asam laktat, total asam tertitrasi, nilai pH, kadar kalsium dan kadar protein pada hidrolisat karapas udang. Fermentasi selama 15 hari adalah perlakuan terpilih karena menunjukkan nilai total asam tertitrasi tertinggi (2,77%) dan pH terendah (6,16). Astaxanthin tidak terdeteksi pada hidrolisat setelah difermentasi. Hidrolisat karapas udang terpilih memiliki asam amino yang didominasi oleh alanin (2,33 mg/g bahan)., Shrimp carapace is a by-product of the shrimp processing industry which has the potential to be used as value-added products including chitin and hydrolyzate through a fermentation process. The aim of this study was to determine the effect of different fermentation times on the microbiological and chemical characteristics, as well as the amino acid and astaxanthin profiles, in selected shrimp carapace hydrolysates. Ten grams of shrimp carapace powder plus 6,5% (w/w) glucose, 100 mL of distilled water, and a 10% (v/w) mixture of starter isolates Lactobacillus plantarum SK(5), Lactobacillus plantarum NS(9), and Pediococcus pentosaceus BP(20) were then fermented. The experimental design used was a completely randomized design with fermentation time factors (5, 10, and 15 days) on pH, total titrated acid (TTA), total lactic acid bacteria (LAB), calcium levels, and protein. The selected treatments were then analyzed for amino acids and astaxanthin. Different fermentation times had a significant effect on total lactic acid bacteria, total titrated acid, pH, calcium content, and protein content in hydrolyzed shrimp carapace. Fermentation for 15 days was the chosen treatment because it showed the highest total titrated acid value (2,77%) and the lowest pH (6,16). Astaxanthin was not detected in the hydrolysate after it was fermented. Selected shrimp carapace hydrolysate had an amino acid profile dominated by alanine (2,33 mg/g material).
Keyword: fermentation, lactic acid bacteria, shrimp carapace hydrolysate, shrimp carapace

Judul: Approximation of the Median of Poisson Distribution Using the Relation of Poisson-Gamma Distribution
Abstrak: A major drawback of median is that median cannot usually be defined in closed form, even in the cases where their distribution functions are known. This study gives an approximation of the closed form for the median of the Poisson distribution by using the relation of Poisson-Gamma distribution. The approximation uses elementary techniques based on the monotonicity of certain sequences involving tail probabilities of the Poisson distribution and the Central Limit Theorem. Furthermore, a closed form expression for the mean absolute deviation 􀜧|􀜰􀰒 􀵆 􀜯􀝁􀝀􁈺􀜰􀰒􁈻| is also studied. The median is relevant because of the fact that it minimizes the mean absolute deviation of a Poisson random variable (􀜰􀰒􁈻 by considering median as central tendency.
Keyword: