Judul: Penambatan Molekuler secara In Silico dan Aktivitas Nanoenkapsulat Kurkuminoid secara In Vitro sebagai Potensi Anti Penuaan Dini.
Abstrak: Kolagenase merupakan senyawa pendegradasi kolagen dan teraktivasi oleh reactive oxygen species sehingga dapat menyebabkan penuaan kulit. Penuaan kulit dapat diatasi oleh produk yang mengandung antioksidan. Suatu senyawa yang memiliki kemampuan dalam mereduksi radikal bebas belum tentu dapat menghambat kolagenase. Kurkuminoid memiliki aktivitas antioksidan, namun bioavailabilitasnya rendah. Peningkatan bioavailabilitas kurkuminoid dapat dilakukan dengan pembuatan nanopartikel. Penelitian bertujuan menguji potensi kurkumin dan turunannya dalam menghambat kolagenase melalui penambatan molekuler dan potensi nanoenkapsulat kurkuminoid sebagai anti penuaan dini secara in vitro. Penambatan molekuler dilakukan antara kolagenase dengan senyawa kurkumin dan turunannya. Nanoenkapsulat kurkuminoid diuji aktivitas antioksidannya menggunakan DPPH dan dianalisis ukuran serta kestabilan nanoenkapsulat kurkuminoid menggunakan PSA (particle size analyzer) dan Zetasizer. Hasil penambatan diperoleh senyawa kurkumin dan turunannya dapat tertambat pada sisi aktif kolagenase. Nanoenkapsulat kurkuminoid memiliki ukuran sebesar 180.3 nm, indeks polidispersitas sebesar 0.476, dan potensial zeta sebesar -45.1 mV. Serbuk enkapsulat memiliki kadar air sebesar 2.16% serta mengandung kurkuminoid sebesar 1.038 mg/g enkapsulat. Aktivitas antioksidan pada nanoenkapsulat kurkuminoid memiliki IC50 sebesar 2.62 μg/mL.
Keyword: antioksidan, antipenuaan, nanoenkapsulat-kurkuminoid, kolagenase, kurkuminoid

Judul: Virtual Screening Natural Polyphenol Compounds as Inhibitor of Matrix Metalloproteinase-1 for Anti Photoaging and Photocarcinogenesis
Abstrak: Matrix metalloproteinase-1 (MMP-1) menjadi enzim yang paling banyak dipicu aktivitasnya oleh sinar UV dan bertanggung jawab terhadap degradasi kolagen. Degradasi kolagen menjadi penyebab utama photoaging dan photocarcinogenesis. Berbagai senyawa aktif telah diteliti aktivitasnya sebagai inhibitor MMP-1, termasuk senyawa polifenol. Saat ini, lebih dari 8000 jenis polifenol telah diidentifikasi di berbagai tanaman dan belum semuanya diteliti. Penelitian ini bertujuan menyaring polifenol alami dari database sebagai inhibitor MMP-1 terbaik. Tahap awal penelitian yaitu dilakukan penapisan virtual 408 polifenol alami menggunakan PyRx dan prediksi bioavailabilitas serta toksisitas menggunakan pkCSM dan Protox online tool, dilanjutkan dengan penambatan molekuler menggunakan AutoDock Vina serta visualisasi 2D dengan LigPlot+ dan 3D dengan PyMol. Terdapat empat senyawa yang diprediksi potensial sebagai inhibitor MMP-1 untuk anti photoaging dan photocarcinogenesis, yaitu luteolinidin, hispidulin, demetoksikurkumin, dan kurkumin. Luteolinidin dan hispidulin menghambat dengan mengkelat Zn katalitik, sedangkan demetoksikurkumin dan kurkumin tanpa mengkelat Zn katalitik, tetapi membentuk interaksi lebih banyak pada kantong S1’. Demetoksikurkumin memiliki kemampuan menghambat terbaik dengan ΔG -10,0 kkal/mol, Ki 0,05 µM, dan BSS 66,77%., Matrix metalloproteinase-1 (MMP-1) is the enzyme that is mostly triggered by UV rays and it is responsible for collagen degradation. Degradation of collagen is the main cause of photoaging and photocarcinogenesis. Various active compounds have been studied for their activity as MMP-1 inhibitors, including polyphenol compounds. Recently, more than 8000 types of polyphenols have been identified in various plants and not all of them have been studied. The research aims to screen virtualy natural polyphenols from database as the best MMP-1 inhibitors. First step of the research is virtual screening of 408 natural polyphenols using PyRx and prediction of bioavailability also toxicity using pkCSM and Protox online tool, followed by molecular docking using AutoDock Vina and 2D visualization with LigPlot+ also 3D with PyMol. There are four compounds predicted as potential MMP-1 inhibitors for anti photoaging and photocarcinogenesis, such as luteolinidin, hispidulin, demethoxicurcumin, and curcumin. Luteolinidin and hispidulin are inhibit by chelating catalytic Zn, whereas demethoxycurcumin and curcumin do not chelate catalytic Zn, but they are form more interactions in the S1' pocket. Demethoxycurcumin has the best inhibitory ability with ΔG -10,0 kcal/mol, Ki 0,05 M, and BSS 66,77%.
Keyword: MMP-1, penapisan virtual, photoaging, photocarcinogenesis, polifenol alami

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