Judul: Free Radical Reduction Activity of DPPH and Inhibition of α-Glucosidase Aqueous Extract of Cinnamon Bark (Cinnamomum burmannii)
Abstrak: Kayu manis (Cinnamomum burmannii) merupakan tanaman herbal yang mempunyai fungsi salah satunya yaitu menurunkan glukosa dalam darah dan menangkal radikal bebas yang menyebabkan stress oksidatif. Penelitian ini bertujuan menentukan rendemen, total fenolik, peredaman radikal bebas DPPH, dan aktivitas penghambatan enzim α-glukosidase pada ekstrak air kulit kayu manis (Cinnamomum burmannii) yang berulang (residu pertama, residu kedua, dan residu ketiga). Metode ekstraksi menggunakan teknik infundasi dan pengujian lanjutan dilakukan menggunakan spektronanometer. Hasil pengujian kadar total fenolik dan aktivitas antioksidan ekstrak residu pertama, residu kedua, dan residu ketiga mendapatkan hasil yang berbeda nyata (p<0,05). Rendemen dan aktivitias inhibisi enzim α-glukosidase ekstrak residu pertama, residu kedua, dan residu ketiga mendapatkan hasil yang tidak berbeda nyata (p>0,05)., Cinnamon (Cinnamomum burmannii) is an herbal plant with various functions, one of them is lowering glucose in the blood and counteracting free radicals that cause oxidative stress. This research was aimed to determine the yield, total phenolic, scavenging of DPPH free radical, and α-glucosidase enzyme inhibitory activities in the aqueous extract of cinnamon bark (Cinnamomum burmannii) that recurs (first residue, second residue, and third residue). Extraction method used the infundation technique and further testing was carried out using spectronometer. Test results of total phenolic content and antioxidant activity of the first, second, and third residual extract got significantly different results (p<0.05). Yield and activity of α-glucosidase enzyme inhibition of the first, second, and the third residue extracts obtained insignificantly different results (p>0.05).
Keyword: Antioksidan, Diabetes Mellitus, Enzim α-Glukosidase, Kayu Manis

Judul: Analisis Penambatan Molekul Senyawa Aktif Kayu Manis (Cinnamon) pada Enzim MGA untuk Agen Anti-Diabetes
Abstrak: Kasus diabetes melitus terus meningkat setiap tahunnya, terutama diabetes melitus tipe II. Salah satu tanaman yang memiliki aktivitas anti-diabetes adalah kayu manis. Kayu manis memiliki senyawa aktif berupa cinnamaldehyde, cinnamic acid, ethyl cinnamate dan cinnamyl acetat yang dipercaya berkhasiat untuk mengobati diabetes namun belum diketahui potensi dari masing-masing senyawa tersebut. Penelitian ini bertujuan untuk mengevaluasi potensi senyawa aktif yang terkandung dalam kayu manis sebagai anti-diabetes melalui simulasi penambatan molekul serta mendapatkan model interaksi antara senyawa aktif kayu manis dengan enzim Maltase-Glucoamylase (kode PDB: 3L4W). Ligan kontrol yang digunakan adalah miglitol sedangkan ligan uji yang digunakan adalah senyawa aktif kayu manis. Hasil simulasi menunjukkan bahwa senyawa ligan uji yang berpotensi sebagai inhibitor enzim MGA untuk agen anti-diabetes mengikuti miglitol adalah senyawa aktif cinnamic acid. Hal tersebut dikarenakan memiliki energi Gibbs ikatan tebesar bahkan menyaingi energi Gibbs ikatan miglitol, konstanta inhibisi terkecil dan ikatan hidrogen terbanyak dibandingkan ligan uji lainnya.
Keyword: kayu manis, penambatan molekul, Maltase-Glucoamylase, senyawa aktif

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.
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