Judul: Produksi, Karakterisasi dan Pemurnian Xilanase dari  Staphylococcus aureus MBXi-K4
Abstrak: Penggunaan dedak gandum (pollard) sebagai salah satu bahan baku pakan terutama ternak monogastrik terkendala oleh kandungan serat kasarnya yang tinggi. Untuk meningkatkan nilai nutrisi bahan pakan berkadar serat tinggi, salah satu upayanya adalah dengan memanfaatkan enzim sebagai imbuhan pakan (feed additive) yang berfungsi untuk memecah komponen serat kasar menjadi produk yang lebih sederhana, yang dapat diserap langsung oleh ternak. Penambahan enzim xilanase pada pakan berbasis dedak gandum (pollard) dapat menurunkan viskositas digesta pada unggas. Xilanase dapat menurunkan viskositas digesta dengan cara menghidrolisis arabinoxilan menjadi arabinosa dan xilosa, sehingga dapat dengan mudah dimanfaatkan oleh unggas.
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Judul: Purifikasi Dan Karakterisasi Xilanase Ekstraseluler Streptomyces sp. SKK1-8 Asal Sukabumi
Abstrak: Hemiselulosa merupakan heteropolimer yang keberadaaannya di alam kedua terbanyak setelah selulosa. Kadar hemiselulosa pada tanaman mencapai 20-30% berat kering kayu. Saat ini sebagian besar limbah hemiselulosa masih belum dimanfaatkan secara optimal padahal berpotensi untuk diolah menjadi berbagai produk yang lebih bernilai ekonomi. Komponen utama hemiselulosa adalah xilan yang memiliki tulang punggung rantai D-xilopiranosa dengan ikatan glikosidik β-1,4. Residu O-asetil, arabinosil dan 4-O-metil asam glukoronat terikat pada tulang punggung xilan. Kadar dan komposisi xilan pada tanaman bervariasi tergantung pada jenis tanaman. Diperlukan kerja sinergi dari beberapa enzim xilanolitik untuk mendegradasi secara lengkap struktur xilan yang kompleks menjadi monomernya. Xilanase merupakan enzim kompleks yang terdiri atas 1,4-β-endoxilanase, β- xilosidase,α L-arabinofuranosidase, α-glukuronidase, asetil xilan esterase dan asam fenolat esterase. Xilanase dan produk hidrolisisnya memiliki potensi untuk diaplikasikan dalam berbagai industri. Xilanase dapat diaplikasikan pada industri kertas, pangan, peternakan dan pengolahan limbah. Xilitol, furfural, xilooligosakarida dan asam glukuronat merupakan produk hidrolisis xilanase yang berpotensi untuk diaplikasikan pada industri pangan, farmasi dan kimia. Xilanase dihasilkan oleh bakteri, cendawan dan khamir. Streptomyces adalah bakteri Gram positif yang membentuk miselium dan telah digunakan untuk mensintesis senyawa antibiotik, metabolit sekunder lain dan enzim dalam skala industri. Beberapa Streptomyces asal Indonesia diketahui berpotensi sebagai penghasil xilanase, diantaranya Streptomyces sp. 1141-1, Streptomyces sp. 234P-16, Streptomyces sp 451-3 dan Streptomyces sp SKK1-8.
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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