Judul: Production and Characterization of Bacteriocin from Lactobacillus fermentum 2B2 and Its Antimicrobial Activities Against Pathogen Bacteria
Abstrak: Bakteri asam laktat (BAL) yang terdapat secara alami di dalam daging atau susu memiliki kemampuan sebagai bahan pengawet alami karena menghasilkan senyawa antimikroba. Salah satu senyawa antimikroba yang dihasilkan yaitu bakteriosin. Penggunaan bakteriosin sebagai biopreservative sangat menjanjikan karena bersifat bakterisidal atau bakteristatik terhadap bakteri lain khususnya bakteri yang berkerabat dekat dengan bakteri penghasilnya (Vuyst and Vandamme, 1994). Potensi bakteriosin ini meningkatkan penelitian dalam mempelajari dan mendapatkan informasi yang lebih dalam mengenai produksi bakteriosin, purifikasi parsial bakteriosin, konsentrasi penghambatan minimum dalam minimum inhibitor concentration (MIC) dan minimum bactericidal concentration (MBC) terhadap bakteri patogen, serta karakterisasi bakteriosin melalui uji kepekaan bakteriosin terhadap enzim katalase dan proteolitik, Produksi dan Karakterisasi Bakteriosin Asal Lactobacillus fermentum 2B2 dan Aktivitas Antimikrobanya terhadap Bakteri Patogen.
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Judul: Produksi dan Karakterisasi  Bakteriosin Asal Lactobacillus  plantarum  1A5 serta Aktivitas Antimikrobanya  terhadap Bakteri Patogen
Abstrak: The aims of this research were to study antimicrobial activity of bacteriocin produced by lactic acid bacteria Lactobacillus plantarum 1A5 in six different media (media with NaCl 1%, combination of NaCl 1% and YE 3%, and trypton 1% inducers that were conditioned on pH 5 dan pH 6, respectively). Characteristic of bacteriocin 1A5 determined by catalase and proteolytic enzymes with antagonistic assay against pathogenic bacterias (Staphylococcus aureus ATCC 25923, Salmonella typhimurium ATCC 14028 and enteropathogenic Escherichia coli K11) and determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericide Concentration (MBC)’s value against Staphylococcus aureus ATCC 25923. The result showed that the inhibitory activity was produced significantly by crude bacteriocin 1A5 from media with trypton 1% inducer and was conditioned at pH 6. Characterization of active compound from crude bacteriocin 1A5 could be classified as bacteriocin neither antimicrobial compounds such as hydrogen peroxide because it was stable to catalase treatment. The other characteristic of its bacteriocin was nature proteinaeous that showed loss it’s activity after trypsin treatment against Staphylococcus aureus ATCC 25923 and enteropathogenic Escherichia coli K11, neither Salmonella typhimurium ATCC 14028. Inhibition activity of crude bacteriocin 1A5 could explained with MIC and MBC’s value, especially against Staphylococcus aureus ATCC 25923. MIC’s and MBC’s value needed respectively 70% dan 80% concentration of crude bacteriocin.
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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