Judul: Kandungan Kimia dan Aktivitas Penghambatan Alfa- Glukosidase secara in vitro dari Ekstrak Metanol Stichopus hermanii dan Spirulina platensis.
Abstrak: Stichopus hermanii dan Spirulina platensis merupakan biota laut yang memiliki potensi sebagai antihiperglikemia berdasarkan penelitian sebelumnya. Tujuan penelitian ini menentukan kandungan kimia dan penghambatan ekstrak metanol dari kedua sampel dan campurannya terhadap enzim α-glukosidase. Analisis kadar logam berat, proksimat dan kadar asam amino dilakukan dalam penelitian sebagai data penunjang. Uji aktivitas ekstrak dalam menghambat α- glukosidase menunjukkan ekstrak spirulina lebih baik dibandingkan ekstrak teripang dan campurannya. Secara berurutan aktivitas penghambatan ekstrak teripang dan spirulina serta campurannya adalah 17.83% pada konsentrasi 25 μg/mL, 21.56% pada konsentrasi 1 μg/mL dan 26.583% pada konsentrasi 500 μg/mL. Berdasarkan analisis proksimat S. hermanii segar memiliki kadar air terbesar (92.74%) sedangkan S. platensis kering memiliki kandungan protein terbesar (40.32%). Sampel teripang segar dan spirulina kering memiliki kandungan 15 asam amino dari 15 macam asam amino yang diujikan. Uji kadar logam berat kedua sampel tidak melebihi ambang batas dan keduanya mengandung mineral seng (Zn) dan besi (Fe).
Keyword: -glukosidase, penghambatan, proksimat, spirulina, teripang

Judul: Aktivitas Penghambatan Malondialdehida (Mda) Secara In Vitro Dan Toksisitas Ekstrak Metanol Stichopus Hermanii Dan Spirulina Platensis
Abstrak: Teripang emas dan Spirulina platensis sp merupakan biota laut yang banyak mengandung senyawa bioaktif dan memiliki efek farmakologi salah satunya sebagai antioksidan. Penelitian ini bertujuan menduga tingkat toksisitas dan aktivitas antioksidan ekstrak metanol teripang jenis Stichopus hermanii dan S. platensis asal Indonesia, serta campuran keduanya. Uji toksisitas dilakukan dengan metode uji BSLT (Brine Shrimp Lethality Test) sedangkan uji aktivitas antioksidan dilakukan dengan metode MDA-TBA. Hasil uji BSLT menunjukkan ekstrak metanol teripang dan campurannya bersifat toksik dengan nilai LC50 sebesar 97.633 ppm dan 186.996 ppm. Sementara itu, ekstrak metanol S. platensis bersifat kurang toksik dengan nilai LC50 4581.550 ppm. Hasil uji potensi antioksidan menunjukkan ekstrak S. platensis konsentrasi 50 ppm memiliki daya hambat 56.53%, tidak berbeda nyata dengan vitamin E konsentrasi 200 ppm (57.67%) (p<0.05). Sementara itu ekstrak teripang emas dan campuran pada konsentrasi 200 ppm memiliki daya hambat yang lebih kecil dibandingkan dengan vitamin E yaitu sebesar 41.26% dan 47.85%.
Keyword: aktivitas antioksidan, BSLT, S, platensis, teripang emas

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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