Judul: Kajian Aktivitas Hambat Pertumbuhan Bakteri  Patogen Oleh Serbuk Bakteriosin Yang  Dihasilkan Bakteri Asam Laktat Galur Scg 1223
Abstrak: The preservative agent is usually add into a product to improve its characteristic. The research on natural preservatives also has been using to reduce the contamination of pathogenic bacteria. The important of preservatives agent is its stability. The stability of inhibition activity of bacteriocins would maintain the ability in reducing the growth of pathogenic bacteria. In the production of food additive is use full to control the water content of bacteriocins and maintained its viability. Bacteriocins produced by Lactic Acid Bacteria strain SCG 1223 was stable at low pH (2-4), 100oC and storage condition of 4oC for 120 days. The best encapsulation formula for bacteriocins was by using 83,33% maltodextrine, 16,67% skim milk, and 20% of liquid bacteriocins SCG 1223. The condition for encapsulation was good if using lower temperature inlet of 150oC and temperature outlet of 75-80 oC. The yield obtained was 69,3% having 2,73% moisture content and 66,81% soluble solids. The low moisture content and high soluble solids showed to increase the inhibition activity.
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Judul: Aktivitas penghambatan bubuk bakteriosin dari bakteri asam laktat galur Scg 1223
Abstrak: Bakteri asam laktat (BAL) dikenal luas dalam pengawetan pangan (fermentasi) karena berbagai jenis metabolit yang dapat dihasilkannya, antara lain berupa senyawa asam laktat dan peptida. Senyawa peptida tersebut dikenal sebagai bakteriosin dan memiliki aktivitas antibakteri, baik bakteristatik maupun bakterisidal. Bakteriosin dalam bentuk supernatan sangat dipengaruhi oleh kondisi penyimpanan, terutama pH dan suhu. Efektifitas antibakteri bakteriosin dapat dipertahankan, salah satunya dengan teknik enkapsulasi. Penelitian ini bertujuan untuk mengetahui aktivitas hambat bubuk bakteriosin dari BAL galur SCG 1223 pada berbagai suhu dan pH pelarutan, serta kondisi penyimpanan (suhu dan umur simpan) Penentuan kondisi optimum pelarutan dan penyimpanan bubuk bakteriosin dari BAL galur SCG 1223 dilakukan dengan mengatur pH dan suhu pelarutan serta umur dan suhu penyimpanan. Pengujian aktivitas dilakukan terhadap dua bakteri uji, yaitu Escherichia coli dan Pediococcus acidilactici. Aktivitas bakteriosin dinyatakan sebagai AU/mL, yaitu luas daerah hambat per satuan volume contoh bakteriosin yang diuji (mm2/mL).
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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