Judul: Pemurnian Parsial dan Karakterisasi Enzim Kitinase dari Beauveria bassiana
Abstrak: Beauveria bassiana si an entomopathogenic fungus that produces chitinase enzyme when infecting its host. The purpose of this study was to perform partial purification and characterization of chitinase enzyme from Beauveria bassiana. The result activity chitinase enzyme of qualitative assay shown that Beauveria bassiana produced ekstracelluler chitinase enzyme with chitinolytic index of 1.035. Purification with ammonium sulfate precipitation produce purity level by 1.2 times than the crude enzyme extract and purification with dialisis techniques can increased the purity of enzim by 1.9 times than the crude enzyme extract. The result of characterization assays shown that chitinase enzyme had an optimum activity of pH 4, temperature 50oC, incubation time 90 minutes, the addition of metal ions Mn2 + served as activators, and chitinase enzyme from Beauveria bassiana had Km of 0.225 mg/L and Vmax of 0.069 mg/L sec. Chitinase enzyme from Beauveria bassiana had a molecular weight at 60.255 kDa
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Judul: Isolasi, Pemurnian Parsial, dan Karakterisasi Enzim Kitinase dari Bacillus sp. BPPT CC 2
Abstrak: Chitinase is a potential enzyme due to its acitvity hydrolyting chitin to its derivates. Therefore, it can be used for various applications, such as agriculture, microbiology, and cosmetic. This study aimed to isolate, purify, and characterize (pH, temperature, metal ion effect, molecular weight, and kinetic parameters) chitinase of Bacillus sp. BPPT CC 2. Ammonium sulphate precipitation and dialysis were used for enzyme purification. Enzyme was characaterized its optimum pH and temperature, metal ions, molecular weight, as well as kinetic parameters. The results showed that enzyme was well precipitated using 80% ammonium sulphate. After dialyzed, level of enzyme purity increased 6.58 fold with specific activity of 0.0924 U/mg. Results showed that the optimum temperature and pH of chitinase were found at 55ºC and pH 5. Value of Km and Vmaks values were 2.705x10-4mg/L second and 0.6959 mg/L. Predicted molecular weight of chitinase was 103 kDa. Addition of metal ions Mn2+and EDTA (5 mM and 10 mM) act as activators of chitinase
Keyword: Bacillus sp. BPPT CC 2, characterize, chitinase, kinetic parameter, purification

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular