Judul: Hubungan antara Lama Distilasi, Kandungan Senyawa, dan Bioautografi Antioksidan Minyak Atsiri Bangle (Zingiber purpureum).
Abstrak: Bangle merupakan salah satu tanaman obat yang mengandung minyak atsiri. Tujuan penelitian ini adalah menentukan kadar minyak atsiri dari rimpang bangle dan membandingkan kandungan senyawanya berdasarkan waktu distilasi. Minyak atsiri bangle didistilasi dengan perbedaan rentang waktu, yaitu 0-3 jam, 3-6 jam, dan 6-9 jam. Kadar senyawa minyak atsiri berbeda bergantung pada lama waktu distilasi. Perbedaan tersebut ditentukan melalui kromatografi gas-spektrometri massa. Kandungan senyawa sabinena optimum pada waktu distilasi 0-3 jam, osimena pada rentang waktu 3-6 jam, dan naftalena pada rentang waktu 6-9 jam. Selain itu, minyak atsiri bangle juga memiliki profil kromatografi lapis tipis dan bioautografinya.
Keyword: bangle, distilasi, KG-SM, KLT, minyak atsiri

Judul: Volatile Metabolite Profile of Bangle (Zingiber cassumunar) and Bangle Hantu (Z. ottensii) Using GC-MS
Abstrak: Bangle (Zingiber cassumunar) dan bangle hantu (Z. ottensii) merupakan tanaman yang termasuk ke dalam famili Zingiberaceae. Penelitian ini bertujuan mengidentifikasi profil metabolit volatil pada minyak atsiri rimpang bangle dan bangle hantu menggunakan kromatografi gas-spektrometri massa serta mengklasifikasikan minyak atsiri kedua tanaman tersebut dengan metode analisis komponen utama (PCA). Hasil penelitian menunjukkan rendemen minyak atsiri kedua spesies dari proses distilasi uap masing-masing 0,16±0,06% (v/b) dan 0,09±0,03% (v/b). Berdasarkan identifikasinya dengan perangkat lunak MS-Dial, senyawa yang mendominasi antara lain sabinena, γ-terpinena, dan mirsena. Model PCA sudah dapat membedakan minyak atsiri dari kedua jenis rimpang, dengan total PC1 dan PC2 sebesar 96%. Selain itu, diketahui cis-etil linalil asetat, mirsena, α-tujena, α-pinena, γ-terpinena, 1,8-sineol, β-osimena, dan orto-simena berpengaruh besar pada arah pengelompokan minyak atsiri bangle hantu. Sementara itu, sabinena ditemukan sebagai satu-satunya senyawa teridentifikasi yang berkontribusi besar dalam pengelompokan minyak atsiri bangle., Bangle (Zingiber cassumunar) and bangle hantu (Z. ottensii) belong to the Zingiberaceae family. This study aims to identify the volatile metabolite profile in the essential oils in both rhizome species using gas chromatography-mass spectrometry and also classify the essential oils using the principal component analysis (PCA) method. The results showed that the yields of the extracted essential oil through steam distillation process were 0.16±0.06% (v/w) and 0.09±0.03% (v/w), respectively. Based on the identification using MS-Dial software, the dominant compound in the essential oils were sabinene, γ-terpinene, and myrcene. The PCA model successfully distinguished the essential oils from bangle and bangle hantu rhizomes through a score plot with a total PC1 and PC2 of 96%. In addition, cis-ethyl linalyl acetate, myrcene, α-thujene, α-pinene, γ-terpinene, 1,8- cineole, β-ocimene, and ortho-cymene gave a significant effect on the grouping of bangle hantu essential oil. Meanwhile, sabinene was the only compound contributing majorly to the grouping of the bangle essential oil.
Keyword: Zingiber cassumunar, Zingiber ottensii, metabolomic, essential oil

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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