Judul: Potensi ekstrak tunggal bangle dan gabungannya dalam meningkatkan aktivitas enzim lipase secara in vitro
Abstrak: Bangle (Zingiber cassumunar Roxb.) telah banyak digunakan sebagai salah satu komponen jamu untuk menurunkan bobot badan, tetapi belum diketahui mekanisme kerjanya. Salah satu mekanisme dalam melangsingkan tubuh adalah dengan meningkatkan aktivitas enzim lipase dalam menghidrolisis lipid. Penelitian ini ingin mengevaluasi potensi beberapa ekstrak bangle dalam meningkatkan aktivitas enzim lipase. Lipase yang digunakan dalam penelitian ini memiliki waktu, suhu, dan pH optimum berturut-turut 30 menit, 35°C dan 7,0, sedangkan konsentrasi substrat dan enzim dalam keadaan optimum sebesar 1,42 µg/µl dan 1,40 10 µg/µL. Untuk optimasi konsentrasi ekstrak, interval yang digunakan dibatasi oleh nilai LC50 dari ekstrak. Hasil ekstrak kasar metanol, air, steroid, dan tanin memiliki konsentrasi optimum sebesar 300 ppm, sedangkan flavonoid sebesar 600 ppm. Pada konsentrasi optimum tersebut, hanya tanin yang dapat meningkatkan aktivitas hidrolitik enzim lipase sebanyak 83,79%, sedangkan ekstrak lain lebih bersifat inhibitor (menurunkan aktivitas enzim). Untuk ekstrak gabungan, hanya flavonoid dan steroid yang menunjukkan efek sinergis, dan meningkatkan aktivitas hidrolitik enzim lipase sebesar 43,94%. Isolat tanin yang lebih bersifat aktivator dipisahkan dengan kromatografi kolom menggunakan Sephadex LH-20. Hasil pemisahan menunjukkan adanya 8 fraksi. Fraksi IV, V, dan VI positif mengandung tanin. Analisis spektroskopi ultraungu dan inframerah dari ketiga fraksi tersebut menunjukkan bahwa fraksi IV, V, dan VI memiliki 2 maksimum sebesar 205, 240, dan 234 nm. Hasil dari analisis spektrum inframerah menunjukkan bahwa fraksi ini mengandung gugus fungsi seperti yang ada pada struktur dasar tanin, yaitu -OH, C=C, C-H, dan C-O.
Keyword: 

Judul: Identifikasi Senyawa Aktif Lengkuas (Alpinia galanga) Dengan LC-MS dan Potensinya Sebagai Inhibitor Lipase Pankreas Secara In Silico
Abstrak: Prevalensi penderita obesitas yang terus meningkat setiap tahunnya, serta risiko komplikasi yang ditimbulkan membuat perhatian besar saat ini. Orlistat berefek buruk karena sifatnya yang bekerja dengan menginhibisi enzim lipase pankreas secara ireversibel. Lengkuas banyak ditemukan di Indonesia diketahui dapat berperan sebagai antiobesitas. Penelitian ini bertujuan mengidentifikasi senyawa aktif lengkuas yang berpotensi memiliki aktivitas inhibisi enzim lipase pankreas dengan menggunakan YASARA. Senyawa aktif lengkuas diekstrak menggunakan etanol 70% dan diidentifikasi menggunakan LC-MS/MS QToF serta dilakukan studi pustaka. Sebanyak 8 senyawa berhasil diidentifikasi menggunakan LC-MS/MS QToF dan termasuk golongan polifenol, fenolik, terpen, dan flavonoid, serta terdapat 38 senyawa yang hasil studi pustaka. Terdapat 4 senyawa aktif lengkuas memiliki potensi antiobesitas dengan empat yang terbaik yaitu, galangin, galaganol C, isorhamnetin, dan kampferide. Galangin menjadi senyawa yang paling potensial menjadi kandidat antiobesitas pada tanaman lengkuas., The prevalence of obesity, which continues to increase every year, as well as the risk of complications caused by it, is of great concern today. Orlistat has adverse effects because it works by irreversibly inhibiting the pancreatic lipase. Galangal, found in Indonesia, is known to act as an antiobesity agent. This study aimed to identify active compounds of galangal that have the potential to inhibit pancreatic lipase using YASARA. The active compounds of galangal were extracted using 70% ethanol and identified using LC-MS/MS QToF and literature study. A total of 8 compounds were successfully identified using LC-MS/MS QToF and included polyphenols, phenolics, terpenes, and flavonoids, and there were 38 compounds from literature studies. There are 4 active compounds that have antiobesity potential with the four best ones, namely, galangin, galaganol C, isorhamnetin, and kaempferol. Galangin is the most potential compound to be an antiobesity candidate in galangal plants.
Keyword: Alpinia galanga, pancreatic lipase, antiobesity, molecular docking

Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
Keyword: