Judul: Molecular Docking of Katuk Leaf (Sauropus androgynus) Flavonoid Active Compound as Antiinflammatory Against COX-2 Enzyme
Abstrak: Cyclooxygenase-2 (COX-2) merupakan enzim pro-inflamasi yang memproduksi prostaglandin. Senyawa flavonoid memiliki peran antiinflamasi berdasarkan uji in vitro dan in vivo. Penelitian ini bertujuan menganalisis interaksi hasil penambatan molekul senyawa aktif flavonoid katuk terhadap enzim COX-2. Penelitian dilakukan dengan metode in silico menggunakan program YASARA structure. Senyawa flavonoid yang digunakan sebagai ligan uji yaitu, apigenin, caffeic acid, chlorogenic acid, ferulic acid, kaempferol, luteolin, myricetin, quercetin dan senyawa hasil isolasi yaitu, sauropunol A, B, C dan D. Ligan alami polmacoxib digunakan sebagai ligan kontrol. Semua ligan uji lolos dalam uji farmakologi, namun beberapa ligan tidak layak dalam uji toksisitas. Seluruh ligan uji kecuali sauropunol C dan D, berinteraksi pada sisi aktif COX-2 (PDB ID:5GMN), yaitu Val509, His94, Ser530, Asn62, Thr198, Thr199, Trp5 dan Gln92. Kaempferol berpotensi dalam menghambat COX-2 dengan ΔG -5,1400 kkal/mol, Kd 0,1691 µM, satu ikatan hidrogen, enam interaksi hidrofobik. Sedangkan ligan kontrol polmacoxib memiliki nilai ΔG lebih rendah, yaitu -2,3050 kkal/mol dengan Kd 20,3492 µM, tiga ikatan hidrogen, delapan ikatan hidrofobik., Cyclooxygenase-2 (COX-2) is a pro-inflammatory enzyme that produces prostaglandins. Flavonoid compounds have anti-inflammatory roles based on in vitro and in vivo tests. This study aimed to analyze the interaction of active flavonoid compounds from katuk with COX-2 enzymes through molecular docking. The study was conducted using in silico methods by YASARA structure program. Flavonoid compounds used as test ligands are apigenin, caffeic acid, chlorogenic acid, ferulic acid, kaempferol, luteolin, myricetin, quercetin and isolated compounds sauropunol A, B, C and D. The natural ligand polmacoxib was used as a control ligand. All ligands passed pharmacological tests, but some ligands were not suitable for toxicity tests. All ligands except sauropunol C and D interacted with active site of COX-2 (Val509, His94, Ser530, Asn62, Thr198, Thr199, Trp5, Gln92). Kaempferol has the potential to inhibit COX-2 with ΔG -5.1400 kcal/mol, Kd 0.1691 µM, one hydrogen bond and six hydrophobic interactions. Meanwhile, the polmacoxib control ligand has a lower ΔG value of -2.3050 kcal/mol with Kd 20.3492 µM, three hydrogen bonds and eight hydrophobic bonds.
Keyword: antiinflammatory, flavonoids, molecular docking, cyclooxygenase-2 (COX-2)

Judul: Prediction of Anti-inflammatory Compounds in Okra Pods (Abelmoschus esculentus L.) in Inhibition of Cyclooxygenase-2
Abstrak: Siklooksigenase-2 (COX-2) mengkatalisis pengubahan asam arakidonat menjadi senyawa mediator inflamasi, seperti prostaglandin (PG). Buah okra memiliki aktivitas antiinflamasi berdasarkan studi in vitro dan in vivo, namun belum diketahui senyawanya yang dapat menginhibisi COX-2. Penelitian ini bertujuan memprediksi aktivitas antiinflamasi senyawa aktif buah okra yang dapat menghambat COX-2 berdasarkan interaksinya dengan residu asam amino sisi aktif, katalitik dan selektif. Perangkat lunak YASARA Structure digunakan untuk penambatan molekuler, sementara Discovery Studio Visualizer dan Pymol digunakan untuk analisis interaksi ligan-reseptor. Penambatan dilakukan pada ukuran gridbox 2,0 Å. Penapisan virtual menghasilkan 16 senyawa aktif buah okra hasil studi pustaka menghambat COX-2 dengan nilai energi bebas pengikatan (ΔG) di atas -6,0 kkal/mol. Hasil ini masih lebih rendah dari asam mefenamat sebagai ligan eksperimental. Kuersetin dan α-cubebene paling potensial menghambat COX-2, dengan nilai ΔG -7,887 dan -7,502 kkal/mol serta Ki 1,63 dan 3,13 μM, namun kelimpahannya rendah di buah okra. Senyawa yang paling melimpah adalah kuersetin-3-O-glukosida (-6,668 kkal/mol), berinteraksi selektif dengan His90, Val523 dan Arg513, sama halnya dengan celecoxib sebagai ligan pembanding., Cyclooxygenase-2 (COX-2) catalyzes the conversion of arachidonic acid into inflammatory mediator compounds, such as prostaglandins (PG). Okra pods has anti-inflammatory activity based on in vitro and in vivo studies, but the compounds that can inhibit COX-2 is not yet known. This study aimed to predict the anti-inflammatory activity of the active compounds of okra pods as COX-2 inhibitor based on their interactions with amino acid residues on the active, catalytic and selective sites. YASARA Structure software was used for molecular docking, while Discovery Studio Visualizer and Pymol were used for ligand-receptor interaction analysis. Molecular docking is done on a gridbox size of 2.0 Å. Virtual screening resulted in 16 active compounds of okra pods from literature study inhibiting COX-2 with binding free energy (ΔG) values above -6.0 kcal/mol. These values is still lower than mefenamic acid as an experimental ligand. Quercetin and α-cubebene were the most potent to inhibit COX-2, with ΔG -7.887 and -7.502 kcal/mol and Ki 1.63 and 3.13 μM, however their abundance was low in okra. The most abundant compound was quercetin-3-O-glucoside (-6,668 kcal/mol) and selectively bind to His90, Val523 and Arg513, similar to celecoxib as a reference ligand.
Keyword: anti-inflammation, COX-2, molecular docking, okra pods, selective

Judul: Rancang Bangun Alat Pengukur Intensitas Hujan Dengan Metode Jungkat-Jungkit Berbasis Sensor Medan Magnet UGN3503.
Abstrak: This research has been done on making rain intensity gauge using a magnetic field sensor UGN3503. Sensor UGN3503 can detect the magnetic field on its surface. The sensor is placed above a seesaw that was inserted magnet. The magnet used is Neodymium magnet is a type of permanent magnet with stongest magnetic field compared to other types of fixed magnetic field magnets. When the seesaw discards rainwater, the distance between sensor and magnet is closer and causing the keluaran voltage of the sensor increases. The keluaran voltage of the sensor is compared with a reference voltage by the comparator so that the sensor keluaran data is in digital form and ready to be processed. As the processing and sending of data used ATmega16 microcontroller, microcontroller take sensor data once every 100 ms and display data to the LCD (Liquid Crystal Display) 16x2. Every 30 minutes the data is processed into the rain intensity is then stored into a computer.
Keyword: rain intensity, seesaw, comparator, microcontroller, sensor UGN3503.