Judul: Peranan Enzim Tripsin, Papain, dan Pepsin Dalam Menentukan Karakteristik Hidrolisat Kolagen
Abstrak: Kolagen merupakan salah satu jenis protein struktural penyusun komponen kulit, gigi, tulang, dan otot. Hidrolisat kolagen merupakan suatu produk yang dihasilkan dari proses hidrolisis polipeptida yang dapat dilakukan secara enzimatis dan kimiawi. Tujuan penelitian ini yaitu menentukan karakteristik hidrolisat kolagen dengan penggunaan enzim yang berbeda. Tahapan penelitian yang dilakukan yaitu karakterisasi kolagen, hidrolisis kolagen, serta karakterisasi hidrolisat kolagen dengan enzim yang berbeda. Kolagen yang digunakan memiliki kandungan protein yang sangat tinggi yaitu sebesar 95,75%. Komposisi asam amino kolagen didominasi oleh asam glutamat yaitu sebesar 7,06%. Hidrolisat kolagen juga didominasi oleh asam amino glutamat yaitu terdapat di perlakuan enzim pepsin sebesar 7,81%, enzim papain sebesar 6,13%, dan enzim tripsin sebesar 6,76%. Hidrolisis kolagen dilakukan menggunakan enzim pepsin, papain, dan tripsin. Derajat hidrolisis merupakan indikator suatu keberhasilan dalam proses hidrolisis, nilai Derajat Hidrolisis tertinggi ada pada perlakuan enzim papain yaitu sebesar 54,98%. Aktivitas antioksidan hidrolisat kolagen yang dihasilkan termasuk kedalam antioksidan lemah., Collagen is a type of structural protein that makes up the components of skin, teeth, bones, and muscles. Collagen hydrolyzate is a product resulting from the hydrolysis of polypeptides that can be carried out enzymatically and chemically. The purpose of this study was to obtain collagen hydrolyzate using different enzymes and to see its antioxidant content. The stages of the research carried out were characterization of collagen, hydrolysis of collagen with different enzymes, and characterization of collagen hydrolyzate. The collagen used has a very high protein content of 95,75%. The amino acid composition of collagen is dominated by glutamic acid, which is 7,06%. The hydrolyzate of collagen is also dominated by glutamic acid, the pepsin enzyme is 7,81%, papain enzyme is 6,13%, and trypsin enzyme is 6,76%. The degree of hydrolysis is an indicator of success in the hydrolysis process, highest value of the degree of hydrolysis with the papain enzyme treatment, which is 54,98%. The antioxidant activity of hydrolyzate collagen is classified as weak antioxidant.
Keyword: collagen hydrolyzate, papain, pepsin, tripsin

Judul: Aplikasi enzim pepsin dari lambung ikan tuna sirip kuning dalam pembuatan hidrolisat kolagen kulit tuna sirip kuning (Thunnus albacares)
Abstrak: Hidrolisat kolagen merupakan produk peptida dengan bobot molekul rendah yang dihasilkan dari proses hidrolisis dengan penambahan enzim pada suhu spesifik. Penelitian ini memiliki tujuan untuk menentukan konsentrasi enzim pepsin dalam proses hidrolisis kolagen dari kulit ikan tuna, serta menentukan karakteristik produk hidrolisat. Penelitian ini dilakukan dengan tiga tahapan yaitu produksi pepsin, ekstraksi kolagen dan hidrolisis kolagen. Ekstraksi kolagen dilakukan menggunakan asam, sedangkan hidrolisis kolagen dilakukan menggunakan enzim pepsin dengan aktivitas 7.000, 14.000 dan 21.000 U. Ekstrak pepsin yang diperoleh memiliki aktivitas sebesar 27.438,50 U/mg. Kolagen yang dihasilkan memiliki bobot molekul 260-150 kDa. Hidrolisat kolagen dengan perlakuan aktivitas pepsin 14.000 dan 21.000 U menghasilkan potongan pita protein dengan bobot molekul 41-3 kDa. Uji aktivitas antioksidan menghasilkan nilai IC50 hidrolisat kolagen dengan perlakuan 7.000 U sebesar 485,9±27,08 ppm, perlakuan 14.000 U sebesar 233,42±2,39 ppm yang paling baik diperoleh hidrolisat kolagen dengan perlakuan 21.000 U sebesar 167,7±0,47 ppm. Hidrolisat kolagen memiliki aktivitas inhibitor ACE pada konsentrasi 0,5 mg/ml protein memperoleh nilai inhibisi paling tinggi pada perlakuan 21.000 U yaitu sebesar 68,63%., Hydrolyzed collagen is a group of peptides with low molecular weight that can be obtained by enzymatic action at a specific incubation temperature. This study aimed to determine the concentration of the pepsin enzyme in the hydrolysis process of collagen from tuna skin and to determine the characteristics of the hydrolyze product. This research was conducted in three stages namely pepsin production, collagen extraction, and collagen hydrolysis. Collagen extraction was carried out using acid, while collagen hydrolysis was carried out using the enzyme pepsin with an activity of 7.000, 14.000 and 21.000 U. Pepsin extract obtained had an activity of 27.438,50 U/mg. The resulting collagen had a molecular weight of 260-150 kDa. Collagen hydrolyze with pepsin activity 14.000 and 21.000 U resulted band in low molecular weight sections in the range of 41-3 kDa. The test of antioxidant activity resulting IC50 value of collagen hydrolyze with 7.000 U treatment was 485,9 ± 27,08 ppm, the 14.000 U treatment was 233,42 ± 2,39 ppm, the best obtained was collagen hydrolyze with 21.000 U treatment of 167,7 ± 0,47 ppm. Collagen hydrolyze has an ACE inhibitory activity at a concentration of 0,5 mg/ml protein, obtaining the highest inhibition value at 21.000 U, which is 68,63%.
Keyword: Antioxidant, Extraction, Hydrolysis, Peptide

Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
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