Judul: Isolasi, pemurnian dan identifikasi senyawa anti-B-laktamase dari streptomyces sp. IVNF1-1(Penghambat pertumbuhan bakteri penyebab diare, EPEC K1-1
Abstrak: Bakteri penyebab diare (EPEC K1-1) memproduksi ß-laktamase, enzim yang memotong cincin ß-laktam dan menimbulkan resistensi EPEC K1-1 terhadap antibiotik ß- laktam. Dalam penelitian ini, upaya mengatasi resistensi dilakukan melalui isolasi senyawa anti-ß-laktamase golongan protein (BLIP) dan asam klavulanat dari Streptomyces sp. IVNF1-1. Upaya ini dilatarbelakangi keragaman mikrob Indonesia yang sangat tinggi dan IVNF1-1 merupakan isolat indigenos potensial yang memberikan hambatan terhadap pertumbuhan EPEC K1-1 dengan diameter zona hambat sebesar 6 mm. Hambatan protein ekstraselular IVNF1-1 terhadap aktivitas enzim ß-laktamase EPEC K1-1 ditentukan dengan metode iodometri yang telah dimodifikasi. Hambatan yang diberikan protein ekstraselular dalam filtrat kultur IVNF1-1 ialah sebesar 84,12%. Pemurnian protein tersebut melalui pengendapan amonium sulfat kejenuhan 80%, dialisis, dan kromatografi filtrasi gel sephadex G-75 menghasilkan BLIP dengan aktivitas hambatan sebesar 11,10%.
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Judul: Aktivitas senyawa anti β-laktamase dari Streptomyces lavendulae IVNF1-1 terhadap iabilitas enteropathogenic escherichia coli (EPEC) K1-1 resisten ampisilin
Abstrak: Antibiotik yang banyak digunakan adalah antibiotik β-laktam, diantaranya adalah penisilin, sefalosporin, dan sefamisin. Penghambatan yang spesifik pada pembentukan lapisan peptidoglikan menjadikan antibiotik β-laktam bersifat selektif, yaitu hanya menghambat pertumbuhan bakteri target tanpa membahayakan sel inang sehingga pemakaian antibiotik ini aman bila dibandingkan antibiotik jenis lain. Resistensi bakteri terhadap antibiotik β-laktam merupakan masalah yang serius di bidang kesehatan. Bakteri menjadi resisten terhadap antibiotik ini karena dapat menghasilkan enzim β-laktamase yang bekerja memecah dan menghidrolisis ikatan amida pada cincin β-laktam sehingga antibiotik ini tidak efektif lagi untuk pengobatan. Enzim β-laktamase dapat diinaktifkan oleh senyawa anti β-laktamase. Aktivitas senyawa anti β-laktamase yang dihasilkan oleh Streptomyces isolat lokal seperti isolat IVNF1-1 diketahui melalui dihasilkannya asam klavulanat dan β-laktamase Inhibitory Protein (BLIP). Aktivitas asam klavulanat dan BLIP dari Streptomyces lavendulae IVNF1-1 dalam menghambat pertumbuhan bakteri patogen belum diketahui sehingga perlu dilakukan penelitian ini. Penelitian ini bertujuan mengkaji aktivitas senyawa anti β-laktamase dari Streptomyces lavendulae IVNF1-1 yaitu asam klavulanat dan BLIP terhadap viabilitas EPEC K1-1 resisten ampisilin.
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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