Judul: Characteristics of Collagen from Pangas Catfish Swim bladder (Pangasius sp.) with Differences Time of Ultrasound
Abstrak: Gelembung renang merupakan hasil samping perikanan yang sebagian komponen utamanya berupa protein kolagen. Kolagen merupakan komponen struktural utama dari jaringan ikat. Penelitian ini bertujuan menentukan komposisi kimia, struktur jaringan gelembung renang ikan patin, proses ekstraksi, serta hidrolisis kolagen gelembung renang ikan patin dengan waktu sonikasi berbeda (0, 10, 15, dan 20 menit). Gelembung renang tersusun atas serat-serat yang menggelombang, memiliki percabangan serta memiliki ruang antar serat. Perlakuan terbaik dari kolagen gelembung renang ikan patin ditentukan berdasarkan analisis ANOVA dan uji lanjut Duncan. Kualitas hidrolisat kolagen terbaik diperoleh dari perlakuan waktu sonikasi 15 menit. Kolagen memperoleh rantai a_(1,) a_(2,) dan ß. Hidrolisat kolagen memiliki gugus fungsi dengan puncak serapan amida A, amida B, amida I, amida II, dan amida III, nilai pH 6,67±0,15, nilai viskositas 4,00±1,92, serta memperoleh aktivitas antioksidan dengan nilai IC50 44,09±0,48., The swim bladder is fishery by-product whose main components are collagen protein. Collagen is the main structural component of connective tissue. This research aims to determine the chemical composition, structure of catfish swim bladder tissue, extraction process, and collagen hydrolysis of catfish swim bladder with different sonication times (0, 10, 15, and 20 minutes). Swim bladder is composed of wavy fibers, have branches and have spaces between fibers. The best treatment of catfish swim bladder collagen was determined based on ANOVA analysis and Duncan's further test. The best quality of collagen hydrolysate was obtained from a sonication treatment time of 15 minutes. Collagen obtained a_(1,) a_(2,) and ß chains. Collagen hydrolysate had functional groups with peak absorption of amide A, amide B, amide I, amide II, and amide III, pH value of 6,67±0,15, viscosity value of 4,00±1,92, and antioxidant activity with IC50 value of 44,09±0,48.
Keyword: antioxidant, hydrolysis, moleculer weight, tissue structure, ultrasound

Judul: Karakteristik Hidrolisat Kolagen dari Kulit Ikan Patin (Pangasius hypophthalmus) dengan Perbedaan Konsentrasi Enzim Papain
Abstrak: Kolagen merupakan struktur protein kompleks yang diperoleh dari jaringan ikat. Pembuatan kolagen secara enzimatis menggunakan enzim papain akan memperoleh produk berupa hidrolisat kolagen. Penelitian ini bertujuan untuk menganalisis perubahan struktur jaringan pada kulit ikan patin sebelum dan setelah dilakukan pretreatment dan ekstraksi, serta menentukan karakteristik hidrolisat kolagen dengan perbedaan konsentrasi enzim papain (1%, 3%, dan 5%). Struktur jaringan kulit ikan patin sebelum pretreatment terlihat benang stratum compactum tebal, sedangkan setelah pretreatment dan ekstraksi terlihat benang stratum compactum terurai dan rusak. Hidrolisat kolagen memperoleh nilai derajat hidrolisis (72,37±1,86)-(97,22±3,93)%, nilai pH (6,23±0,12)-(7,22±0,08), dan nilai bobot molekul 12,016-23,877 kDa. Potensi aktivitas antioksidan yang diperoleh tergolong sangat kuat pada metode FRAP dan ABTS. Aktivitas antioksidan pada metode FRAP memperoleh nilai sebesar (536,31±2,61)(641,43±4,08) μmol Fe(II)/g, sedangkan pada metode ABTS memperoleh nilai sebesar (38,02±1,72)-(54,17±0,98) ppm., Collagen is a complex protein structure obtained from connective tissue. Enzymatic production of collagen using the papain enzyme will obtain a product in the form of collagen hydrolyzate. This study aims to analyze changes in the tissue structure of catfish skin before and after pretreatment and extraction, and to determine the characteristics of collagen hydrolyzate with different concentrations of papain enzymes (1%, 3%, and 5%). The structure of the catfish skin tissue before pretreatment showed thick stratum compactum threads, whereas after pretreatment and extraction, the stratum compactum threads were seen to be decomposed and damaged. Collagen hydrolyzate obtained a hydrolysis degree of (72.37±1.86)-(97.22±3.93)%, a pH value of (6.23±0.12)-(7.22±0.08), and a molecular weight value of 12.016-23.877 kDa. The potential antioxidant activity obtained is classified as very strong in the FRAP and ABTS methods. The antioxidant activity in the FRAP method obtained a value of (536.31±2.61)(641.43±4.08) mol Fe(II)/g, while the ABTS method obtained a value of (38.02±1.72)-(54.17± 0.98) ppm.
Keyword: antioxidant, collagen hydrolyzate, papain enzyme, structural change

Judul: Eksplorasi Masalah Logaritma Diskret pada Finite Field G P(2m)
Abstrak: Discrete logarithm problem represents a problem which is defined as modular arithmetic. It is often used to generate a key pair on public key cryptography as security object. Given cyclic group G of order n, αgenerator of G, and β∈􀜩, then, in general, discrete logarithm problem is determined as the integer 􀝔, 0≤􀝔≤􀝊−1, such that α􀯫≡β(mod 􀝊). In Menezes et al. (1997) the algorithm to solve the discrete logarithm problem in common cyclic group G are Exhaustive Search algorithm, Baby-Step Giant-Step, Pollard's rho, Pohlig Hellman and Index Calculus. Furthermore, these algorithms are explored to determine the solution of discrete logarithm problem on 􀜩􀜨(2􀯠). The reconstructed algorithms are implemented using Maple 11 software. These implementation can be used to measure security level of cryptography algorithm, which is based on security aspects of discrete logarithm problem
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