Judul: Penapisan Virtual Senyawa Polifenol Alami sebagai Inhibitor Beta-Laktamase untuk Penanganan Resistensi Antibiotik BetaLaktam
Abstrak: Pemakaian antibiotik yang tidak sesuai dengan indikasinya dapat menyebabkan resistensi. Beta-laktamase dapat menurunkan efektivitas betalaktam dan menyebabkan resistensi antibiotik. Senyawa polifenol adalah senyawa metabolit sekunder yang banyak ditemukan pada berbagai tanaman dan beberapa diketahui dapat menghambat aktivitas enzim beta-laktamase. Penelitian ini bertujuan menyaring senyawa polifenol alami di data bank molekul yang memiliki potensi terbaik sebagai inhibitor beta-laktamase menggunakan penapisan virtual, pengujian interaksi molekuler, prediksi druglikeness, farmakokinetika, serta toksisitas ligan. Berdasarkan analisis pada 112 ligan uji polifenol alami, didapatkan 6 ligan yang diprediksi potensial sebagai inhibitor beta-laktamase. Trans-resveratrol 3-O-glucuronide memiliki pengikatan paling stabil dengan nilai energi bebas ikatan (ΔG) sebesar -8,1 kkal/mol dan konstanta inhibisi (Ki) sebesar 1,137 µM. Namun, keenam ligan uji terpilih dapat dikategorikan baik dan tidak toksik sehingga dapat menjadi kandidat inhibitor CTX-M beta-laktamase.
Keyword: ADMET, beta-laktamase, natural polyphenolic, virtual screening

Judul: Potensi Senyawa Aktif Sungkai (Peroema canescens) dalam Menginhibisi Enzim Beta-Laktamase Secara In Silico.
Abstrak: Kasus resistensi bakteri terhadap antibiotik menjadi ancaman serius bagi kesehatan manusia karena menurunkan efektivitas obat untuk mencegah dan menyembuhkan infeksi bakteri. Resistensi dapat disebabkan oleh pengobatan yang tidak tuntas. Salah satunya yaitu bakteri Escherichia coli yang menghasilkan enzim CTX-M yang merupakan jenis dari beta-laktamase yang menghambat kerja antibiotik golongan beta-laktam. Sungkai merupakan salah satu tanaman obat tradisional dan terbukti menghambat pertumbuhan bakteri Escherichia coli. Penelitian ini bertujuan mengidentifikasi senyawa aktif sungkai yang berpotensi menginhibisi beta-laktamase serta analisis interaksi yang terjadi secara in silico. Senyawa aktif daun sungkai ditambatkan ke reseptor beta-laktamase, kemudian dianalisis interaksinya serta diprediksi bioavailabilitas dan toksisitas. Hasil penelitian menunjukan sebanyak 6 dari 19 ligan uji lolos penapisan hingga akhir dan berpotensi menjadi inhibitor beta-laktamase. Senyawa tersebut antara lain, beta-sitosterol, 3,4’,5-thrihydroxy-3,’,7-dimenthoxyflavanone, physcion, isorhamnetin, chrysoeriol, quercetin 3,3 dimetly ether, dan vintexin-2-O rhamnoside., Cases of bacterial resistance to antibiotic has become a serious threat for human health because they reduce the effectiveness of drugs in preventing and treating bacterial infections. Resistance can be caused by uncomplete treatment. One of example is Escherichia coli bacteria which produces the CTX-M enzyme, that is a type of of beta-lactamase that inhibits the action of beta-lactam antibiotics. Sungkai is one of the traditional medicinal PLANTS and it is proved inhibiting the growth of Escherichia coli. This research aims to identify the active compounds of sungkai that have the potential to inhibits beta-lactamase and analyze interactions of molecular docking. The active compounds of sungkai leaves are docked to the beta-lactamase receptor, then their interactions are analyzed, predicting bioavailability, and toxicity. The results showed that 6 of the 19 tested ligands pass the screening and have the potential to become beta-lactamase inhibitors. The compounds are beta-sitosterol, 3,4’,5-thrihydroxy-3’7-dimenthoxyflavanone, physcion, isorhmaetin, chrysoeriol, quercetin 3,3 dimetly ether, and vintexin-2-O-rhamnoside.
Keyword: resistent, beta-lactamase inhibitors, sungkai

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