Judul: Production and Immobilization of Pectinase from Bacillus sp. 2P11 Using Alginate Beads
Abstrak: Enzymes are biocatalysts with high catalytic power that have the potential to be used in the industrial field. Pectinase is an enzyme that degrades plant cell walls and is commonly used in the food industry to accelerate the extraction of fruit juices. Microbes are a source of enzymes that are often used because they grow on various media and can easily be increased by adjusting the growth conditions. Immobilization is the stage of developing a sustainable bioprocess by reusing enzymes bound to a matrix. Therefore, this study aimed to immobilize the pectinase enzyme and the efficiency of repeated use of the immobilized pectinase. This research begins with the rejuvenation of Bacillus sp. 2P11, which has been isolated from previous studies. The cocoa husk contains pectin, which can be used as a substrate to produce pectinase. Pectinase production was carried out by growing Bacillus sp. 2P11 on liquid production media with a cocoa liquid substrate with variations (1-15%) was tested for enzyme activity. Crude extract enzyme activity was obtained by optimizing microbial growth on the media by making an enzyme production curve. The enzyme production curve makes with an incubation time of 96 hours and observations every 12 hours. Enzyme activity was measured using Dinitrosalicylic Acid (DNS) reagent with a standard solution of galacturonic acid. Precipitation was carried out with ammonium sulfate salt and then dialyzed. The enzyme was precipitated gradually from 0% to the ammonium sulfate saturation level of 80%. Dialysis was carried out by inserting a cellophane tube containing the enzyme into a 0,05 M pH 5 acetate buffer. The purified pectinase was then immobilized by trapping using sodium alginate and CaCl2. Immobilized pectinase stored for 14 days was measured for its enzyme activity repeatedly. The activity of the crude extract of the pectinase enzyme obtained was 0,41 U/mL. Precipitation with ammonium sulfate and dialysis increased pectinase activity by 0,45 U/mL and 0,58 U/mL, respectively. Enzymes can be used repeatedly with enzyme immobilization. In this study, the immobilization of the enzyme entrapment method with sodium alginate and CaCl2 was designed with the response surface method. The optimum concentration of sodium alginate was 0,5%, and CaCl2 0,3 M, with the percentage of an immobilized enzyme was 40,7%, and pectinase activity was 0,23 U/mL. Stability and repeated use of immobilized pectinase can be done up to 5 times., Enzim adalah biokatalis dengan daya katalik tinggi yang memiliki potensi untuk digunakan pada bidang industri. Pektinase merupakan enzim pendegradasi dinding sel tanaman yang umum digunakan untuk industri pangan seperti mempercepat ekstraksi sari buah. Mikroba merupakan sumber penghasil enzim yang sering digunakan karena tumbuh pada berbagai media dan mudah ditingkatkan hasilnya dengan mengatur kondisi pertumbuhan. Imobilisasi merupakan tahapan pengembangan bioproses berkelanjutan dengan menggunakan kembali enzim yang terikat pada suatu matriks. Oleh karena itu, tujuan penelitian ini yaitu melakukan imobilisasi enzim pektinase dan mengukur efisiensi penggunaan berulang pektinase imobil tersebut. Penelitian ini diawali dengan peremajaan isolat Bacillus sp. 2P11 yang telah diisolasi dari penelitian terdahulu. Kulit kakao mengandung pektin sehingga dapat digunakan sebagai substrat untuk menghasilkan pektinase. Produksi pektinase dilakukan dengan menumbuhkan Bacillus sp. 2P11 pada media
Keyword: Alginate beads, Bacillus sp. 2P11, cacao, pectinase, immobilization

Judul: Development of Pectinase Enzyme production from Actinomycetes for Pectiologosaccharide production
Abstrak: Indonesia mempunyai megabiodiversitas mikroba yang luar biasa baik dari mikroba darat maupun mikroba laut yang potensial untuk digunakan sebagai sumber enzim baru termasuk pektinase. Aktinomisetes diketahui mempunyai potensi sebagai penghasil berbagai senyawa bioaktif dan penghasil enzim untuk aplikasi di berbagai industri termasuk industri pangan. Oleh karena itu perlu dilakukan penapisan terhadap koleksi isolat Aktinomisetes laut koleksi InaCC untuk mendapatkan kandidat isolat unggul penghasil pektinase yang mempunyai kemampuan menghidrolisis pektin untuk produksi pektioligosakarida (POS). Penapisan aktinomisetes darat dan identifikasi secara molekuler 16S rRNA yang dilakukan pada penelitian sebelumnya menunjukkan bahwa aktinomisetes darat penghasil pektinase teridentifikasi sebagai Kitasatospora sp. Penelitian ini difokuskan untuk melakukan penapisan aktinomisetes laut penghasil enzim pektinase serta melakukan penelitian lanjutan yaitu proses produksi, purifikasi, karakterisasi, dan analisis potensinya untuk produksi POS dari substrat pektin. Penapisan dilakukan dengan menggunakan metode Double Layer Agar (DLA), kemudian dilakukan tahapan purifikasi enzim pektinase menggunakan kolom kromatografi penukar anion, dilanjutkan dengan uji karakterisasi serta hidrolisis substrat pektin untuk produksi pektioligosakarida serta analisis produk hidrolisis dengan TLC. Hasil penapisan diperoleh satu isolat unggul penghasil pektinase dengan diameter zona bening sekitar 3,7 cm pada larutan pH 7,0 yaitu isolat BLH 1-20. Hasil identifikasi secara molekular dengan sekuen 16S rRNA menggunakan BLAST menunjukkan bahwa isolat BLH 1-20 tersebut adalah Streptomyces sampsonii. Hasil karakteriasai uji pH diperoleh nilai aktivitas 5,141 U/mL pada pH .6.0, sedangkan pada uji suhu diperoleh suhu optimum pektinase pada suhu 30 °C dengan aktivitas sebesar 5,395 U/mL. Hasil pemurnian enzim pektinase dari Kitasatospora sp. dengan metode anion exchange menggunakan kolom kromatografi 5 mL QFF secara parsial menunjukkan kromatogram dengan satu puncak utama pada aktivitas enzim pektinase maupun protein enzim dengan nilai aktivitas berturut-turut sebesar 0,089 U/mL dan 1,096 mg/mL. Karakterisasi enzim dengan uji pH dan suhu menunjukkan pH optimum pektinase terdapat pada larutan fosfat pH 8,0 dengan nilai aktivitas sebesar 0,271806 U/mL, suhu optimum diperoleh pada suhu 40 °C dengan aktivitas sebesar 0,294 U/mL, dan stabilitas pektinase dicapai pada suhu 40 °C dengan waktu inkubasi 30 menit sebesar 0,275 U/mL. Hasil analisis TLC menunjukkan pektioligosakarida yang terbentuk dari hasil hidrolisis pektinase Kitasatospora sp. terjadi pada jam ke 24 – 96
Keyword: aktinomisetes, hidrolisis, karakterisasi, pektinase, purifikasi

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