Judul: Pemurnian dan pencirian protease dari isolat bakteri W-1 yang dihasilkan oleh tauco hitam
Abstrak: Enzim protease dari isolat bakteri W-1 yang diisolasi dari tauco hitam memiliki aktivitas fibrinolitik. Penelitian ini bertujuan memurnikan dan mencirikan protease dari isolat bakteri yang diisolasi dari tauco hitam yang merupakan salah satu makanan fermentasi tradisional Indonesia. Ekstrak enzim dimurnikan dengan presipitasi amonium sulfat kejenuhan 70%, dialisis (cut off 10 kD), dan kromatografi penukar ion DEAE Sepharose. Pemurnian menghasilkan satu fraksi enzim aktif. Aktivitas spesifik fraksi aktif adalah 3.860 U/mg dengan tingkat kemurnian 11.42 kali dibandingkan dengan ekstrak enzim kasar. Hasil analisis SDS-PAGE 15% memperlihatkan fraksi aktif protease terdiri atas 2 pita protein (29.7 dan 33.3 kD). Aktivitas optimum protease dicapai pada suhu 50oC dan pH 7. Uji zimogram 15% memperlihatkan bahwa protease mampu menghidrolisis substrat kasein dan fibrinogen dengan konsentrasi 0,01% (b/v). Aktivitas enzim protease menurun dengan adanya penambahan ion Na+, K+, Mg2+, Mn2+, dan Cu2+ (5 mM). Protease ekstrak kasar dihambat spesifik oleh inhibitor fenilmetilsulfonilklorida, N-p-tosil-L-lisin klorometilketon, dan soybean trypsine inhibitor sehingga digolongkan ke dalam kelompok protease serina.
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Judul: Isolasi dan karakterisasi enzim proteolitik dari ekstrak tape
Abstrak: Tape ketan putih merupakan produk fermentasi beras ketan putih oleh bantuan ragi. Bakteri di dalamnya diduga mengandung enzim protease fibrinolitik yang dapat membantu proses penguraian darah beku. Penelitian ini bertujuan mengisolasi bakteri tersebut lalu mencirikan enzim yang dihasilkannya. Ada 9 isolat yang diujikan, dan diketahui isolat TP-4 diketahui memiliki aktivitas protease maksimum, yaitu 0.724 U/ml. Ektrak enzim protease yang dihasilkan dimurnikan melalui beberapa tahapan: (1) presipitasi amonium sulfat 65%, (2) dialisis (cut off 10 kD), dan (3) pemekatan dengan poli(etilena glikol) (PEG). Hasil aktivitas spesifik dialisat adalah 0.881 U/mg dengan tingkat kemurnian 0.701 dibandingkan dengan ekstrak enzim kasar (1.257 U/mg). Analisis SDS-PAGE 10% pada enzim kasar, presipitat, dan dialisat mempunyai 1 buah pita protein (11.60 kD). Uji zimografi menunjukkan bahwa enzim protease ini mempunyai aktivitas kaseinolitik, fibrinolitik, dan gelatinolitik. Ekstrak enzim kasar dihambat secara spesifik oleh etilenadiamina tetraasetat sehingga digolongkan ke dalam kelompok protease logam sedangkan dialisat dihambat secara spesifik oleh N-p-tosil-L-lisinklorometil keton, dan fenilmetilsulfonil fluorida sehingga digolongkan ke dalam protease serin.
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Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite