Judul: Aktivitas Ekstrak Cengkeh Sebagai Agen Anti-aging pada Saccharomyces cerevisiae
Abstrak: Cengkeh (Syzygium aromaticum) merupakan salah satu tumbuhan Indonesia yang menghasilkan antioksidan. Hingga saat ini, aktivitas cengkeh sebagai zat antioksidan dan potensinya sebagai senyawa anti-penuaan (antiaging) in vivo belum pernah dilaporkan. Saccharomyces cerevisiae merupakan khamir yang banyak dijadikan sebagai model untuk mengetahui biologi molekular dan biokimia pada level seluler. Oleh karena itu, penelitian ini bertujuan mengetahui pengaruh ekstrak cengkeh terhadap masa hidup S. cerevisiae. Bunga cengkeh diekstraksi menggunakan metode maserasi. Metode yang digunakan untuk analisis penuaan sel dan pengaruh ekstrak cengkeh pada viabilitas khamir terhadap cekaman oksidatif adalah metode spot test. Khamir diamati aktivitas mitokondrianya menggunakan mikroskop fluoresens. Ekstrak cengkeh diketahui mampu memperpanjang masa hidup khamir dan mampu meningkatkan toleransi khamir terhadap cekaman oksidatif. Kemampuan tersebut diduga melalui peningkatan aktivitas mitokondria khamir.
Keyword: Saccharomyces cerevisiae, metode spot test, zat antioksidan

Judul: The Effect of Ethanol Derived Fraction of Clove Leaves  and Eugenol as Source of Antioxidants in Delaying Aging on Cellular and  Molecular Level
Abstrak: Cengkeh (Syzygium aromaticum) adalah anggota famili Myrtaceae yang dikenal memiliki aktivitas antioksidan dan antivirus yang tinggi. Antioksidan dibutuhkan oleh sel untuk mencegah adanya akumulasi oksigen reaktif (ROS) di dalam sel. Aktivitas antioksidan ekstrak cengkeh diduga berkorelasi dengan perpanjangan masa hidup seluler (aktivitas antipenuaan). Ekstrak kasar daun cengkeh telah dilaporkan memperpanjang masa hidup sel khamir, namun masih kurangnya informasi yang tersedia mengenai aktivitas antipenuaan dari fraksi etanol daun cengkeh dan eugenol. Dengan demikian, tujuan dari penelitian ini adalah untuk menganalisis cara kerja fraksi etanol daun cengkeh (konsentrasi 25, 50,75,100 μg.mL-1 ) dan eugenol (konsentrasi 10, 20, 30 dan 40 μg.mL-1 ) pada tingkat seluler dan molekuler dalam memperpanjang masa hidup organisme model khamir Schizosaccharomyces pombe. Analisis yang di lakukan pada penelitian ini adalah analisis seluler dan analisis molekuler. Analisis seluler yang digunakan dalam penelitian ini terdiri atas analisis viabilitas sel dan uji toleransi khamir terhadap cekaman oksidatif dengan metode spot test assay, analisis CLS (Chronological life span) dengan teknik TPC (total plate count), dan uji aktivitas mitokondria. Analisis molekuler yang dilakukan adalah protein docking dan analisis transkriptomik. Hasil penelitian menunjukkan bahwa fraksi etanol daun cengkeh dan senyawa eugenol dapat memperpanjang umur khamir pada konsentrasi terendah, yakni masing-masing 25 ppm dan 10 ppm. Hasil pengujian juga menunjukkan bahwa fraksi etanol daun cengkeh dan senyawa eugenol dapat menginduksi toleransi khamir terhadap stres oksidatif (1mM, 2mM, dan 3mM H2O2). Analisis penambatan molekul yang telah dilaksanakan mengungkapkan bahwa senyawa eugenol dapat mengikat protein regulator respon sel terhadap stres oksidatif, diantaranya protein sty1 dan ctt1, tetapi tidak pada sisi aktif. Hasil transkriptomik menunjukkan penurunan ekspresi gen mip1 yang menyandikan Mip1 subunit protein TORC1, serta meningkatkan regulasi scr1 yang terlibat dalam aktivitas mitokondria. Penghambatan aktivitas TORC1 serta peningkatan aktivitas mitokondria diketahui meningkatkan usia kronologis khamir. Secara keseluruhan, penelitian ini menunjukkan adanya potensi aktivitas antipenuaan senyawa eugenol dan cara kerjanya pada tingkat molekuler, Clove (Syzygium aromaticum) belongs to Myrtaceae family which is known to have high antioxidant and antiviral activity. Antioxidants are needed by cells to prevent the accumulation of reactive oxygen species (ROS). The antioxidant activity of clove extract presumably correlates with the extension of cellular life span (antiaging activity). Crude extract of clove leaves has been reported to prolong the life span of yeast cells, however lack of information available regarding antiaging activity of its corresponding ethanol fraction and eugenol. Thus, the aim of this study was to analyze the mode of action of ethanol fraction of clove leaves (concentration 25, 50, 75 and 100 μg.mL-1 ) and eugenol (with concentration 10, 20, 30, and 40 μg.mL-1 ) at the cellular and molecular levels in prolonging life span of the yeast model organism Schizosaccharomyces pombe. The analysis carried out in this research were cellular analysis and molecular analysis. Cellular analysis conducted in this study consisted of cell viability analysis and yeast tolerance test against oxidative stress by spot test assay method, CLS (Chronological life span) analysis with TPC (total plate count) technique, and mitochondrial activity test. Molecular analysis carried out were protein docking and transcriptomic analysis. The results showed that the ethanol fraction of clove leaves and eugenol
Keyword: antiaging, TORC1, transcriptomic, Schizosaccharomyces pombe

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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