Judul: Fermentasi dan pemurnian enzim protease dari Bacillus steatrothermophilus BCC 611
Abstrak: Enzim protease adalah salah satu enzim yang bernilai ekonomi tinggi dengan berbagai pengunaannya baik untuk in- dustri pangan maupun industri non pangan. Enzim ini dapat diproduksi oleh hewan, tumbuhan, dan mikroba, tetapi sumber mikroba paling banyak dikembangkan karena mempunyai beberapa kelebihannya diantaranya produktivitas yang tinggi. Salah satu mikroba penghasil enzim protease adalah B. stearother- mophilus. Penelitian ini dilakukan dalam dua tahap yaitu telaah fermentasi dan pemurnian. Pada tahap pertama dilakukan pe- milihan media fermentasi (limbah cair tahu dan media sinte- tik), suhu fermentasi (37°C dan 50°C) dan waktu fermentasi optimum (6, 12, 24, 36,48 jam, 3 dan 4 hari). Pada tahap selanjutnya dilakukan pemurnian enzim yang diperoleh dari kondisi optimum tahap awal. Dari hasil penelitian pendahuluan didapatkan bahwa me- dia sintetik lebih baik dibandingkan dengan media limbah cair tahu, dimana aktivitas maksimum dengan menggunakan me- dia sintetik 1.252 U/ml dan limbah cair tahu 0.628 U/ml pada suhu fermentasi 37°C. Waktu fermentasi optimum adalah 3 hari. ...
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Judul: Produksi dan pemurnian protease dari Bacillus stearothermophilus NRRL B 1172 dengan filtrasi gel
Abstrak: Penelitian ini terdiri dari tiga tahap yaitu optimasi media fermentasi, produksi serta pemurnian protease Bacillus stearothermophilus dengan kolom filtrasi gel. dari Pada optimasi media fermentasi diperoleh bahwa media fermentasi yang terdiri dari limbah cair tahu + 4% ampas tapioka memberikan aktivitas enzim yang lebih tinggi di- bandingkan dengan media fermentasi lainnya limbah cair tahu + ampas tapioka (0%, 2%, 8%) dan media sintetik. Semua media fermentasi yang dicobakan memberikan waktu optimum 24 jam, setelah itu menunjukkan penurunan aktivitas protease. Media limbah cair tahu + 4% ampas tapioka memberikan aktivitas protease maksimum sebesar 0.980 U/ml enzim, limbah cair tahu + ampas tapioka lainnya 0%, 2% dan 8 % serta media sintetik memberikan aktivitas protease secara berturut-turut dan 0.422 U/ml. sebesar 0.559 U/ml, 0.786 U/ml, 0.561 U/ml Tahap fraksinasi protein enzim dilakukan dengan penam- bahan amonium sulfat pada filtrat fermentasi sebanyak 60 % (% kejenuhan) dan endapannya memberikan aktivitas maksimum sebesar 0.240 U/ml, sedangkan penambahan amonium sulfat ...
Keyword: Enzim protease, Bacillus stearothermophilus NRRL B 1172, Filtrasi gel, Protease dari mikroba, Media fermentasi, Pemurnian enzim protease

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