Judul: Mempelajari aktivitas Antibakterial Biji Picung (pangium edule Reinw.) Terhadap Beberapa Bakteri Pembusuk Ikan Secara Invitro
Abstrak: Penelitian ini bertujuan untuk mempelajari aktivitas antibakterial biji picung terhadap beberapa bakteri pembusuk ikan secara invitro sehingga dapat diketahui mekanisme pengawetan biji picung terhadap ikan. Biji picung yang digunakan yaitu biji yang masih segar, sedangkan bakteri yang digunakan adalah bakteri gram positip batang (Bacillus sp.), gram positip kokkus (Micro- coccus sp.), gram negatip batang nonfermentatif (Pseudo- monas sp:) dan bakteri gram negatip batang fermentatif (Coliform) yang diisolasi dari ikan mas (Cyprinus carpio Linn.) yang dibusukkan pada suhu kamar selama 24 jam. Pengamatan penghambatan pertumbuhan bakteri oleh biji picung dilakukan di dalam media "Nutrient Broth" yang mengandung biji picung dengan konsentrasi 0, 3, 5 dan 7% (b/v) dengan waktu inkubasi 0, 24, 48 dan 72 jam, sedangkan pengamatan letalitas biji picung dilakukan dalam larutan buffer fosfat (pH 7) yang mengandung biji pi- cung dengan konsentrasi 0, 5 dan 7% (b/v) dengan waktu kontak 0, 2, 4, 6 dan 8 jam. Pada konsentrasi biji picung 3% (b/v) telah mampu menghambat pertumbuhan keempat jenis bakteri yang diguna- kan, sedangkan pada konsentrasi 5% (b/v) atau lebih ber- sifat bakterisidal terhadap keempat jenis bakteri terse- but. Bakteri gram positip batang (Bacillus sp.) dan kokkus (Micrococcus sp.) lebih sensitif terhadap biji picung apabila dibandingkan dengan bakteri gram negatip batang (Pseudomonas sp. dan Coliform). Bakteri yang paling sen- sitif terhadap biji picung adalah Micrococcus sp. dan bakteri yang paling resisten adalah Coliform. Letalitas biji picung terhadap Bacillus sp., Micro- coccus sp., Pseudomonas sp. maupun bakteri Coliform sebanding dengan konsentrasi biji picung maupun waktu kontaknya. Komponen antibakteri biji picung yang diduga mempe ngaruhi pertumbuhan Bacillus sp., Micrococcus sp., Pseudomonas sp. dan bakteri Coliform adalah asam sianida, asam hidnokarpat, asam khaulmograt, asam gorlat dan tanin…
Keyword: 

Judul: Picung sebagai bahan pengawet ikan
Abstrak: Penelitian ini dilakukan untuk mengetahui penyebab daya awet picung terhadap ikan. Perlakuan yang diberikan terhadap picung adalah interaksi antara perlakuan "blanching" selama 0, 1, 3 dan 5 menit dengan perlakuan perendaman dalam air mengalir selama O dan 24 jam. Pengamatan dilakukan terhadap daya simpan ikan, "Total Volatule Nitrogen" (T.V. N.) ikan, pH ikan, mikrobiologi dan kadar HCN picung. Rancangan yang digunakan adalah Rancangan Acak Lengkap dengan percobaan faktorial. Dari hasil penelitian diketahui bahwa picung yang direndam dalam air mengalir selama 24 jam maka daya pengawet picung hilang, disamping itu juga kadar HCN dalam picung sebagian besar hilang. Perlakuan "blanching" juga menyebabkan daya pengawet picung hilang dan makin lama waktu "blanching" maka daya pengawet dan kadar HCN picung makin hilang. Pengamatan mikrobiologi menunjukkan bahwa diameter daerah dimana bakteri pembusuk ikan tidak tumbuh pada picung tanpa perlakuan, lebih besar daripada semua perlakuan dan makin lama waktu "blanching" maka diameternya makin kecil. Mekanisme picung dalam pengawetan ini disebabkan karena pembebasan HCN dari ikatan "cyanogen glycoside" oleh suatu enzim yang terdapat dalam picung. Perlakuan perendaman dalam air mengalir dan perlakuan "blanching" menyebabkan sebagian besar kadar HCN picung hilang sehingga daya pengawet picung hilang.
Keyword: 

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