Judul: Pembuatan pepton dari bungkil kedelai dan limbah bir  dengan enzim papain untuk media pertumbuhan bakteri
Abstrak: Penelitian ini dilakukan dalam rangka memanfaatkan bungkil kedelai dan limbah pengolahan bir menjadi produk pepton untuk media pertumbuhan bakteri. Proses pembuatan pepton dilakukan dengan reaksi hidrolisis menggunakan papain kasar hasil produksi lokal.
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Judul: Pembuatan Pepton Kacang Tanah dengan Enzim Papain Kasar untuk Media Pertumbuhan Bakteri
Abstrak: Pepton merupakan komponen penting dalam media pertumbuhan mikroba yang berperan sebagai sumber nitrogen. Rata-rata impor pepton yang mencapai US $17.84 juta per tahun dalam lima tahun terakhir merupakan peluang tersendiri untuk pengembangan pepton dengan memanfaatkan bahan sumber protein yang tersedia di Indonesia, seperti kacang tanah. Tujuan penelitian ini adalah untuk menghasilkan pepton kacang tanah dengan hidrolisis enzimatis menggunakan enzim papain kasar, menentukan kondisi hidrolisis terbaik (waktu hidrolisis, konsentrasi enzim, dan suhu hidrolisis), dan mengujicobakan pepton kacang tanah sebagai media pertumbuhan bakteri. Kadar protein kacang tanah yang digunakan adalah 21.84% dan aktivitas enzim papain kasar yang digunakan sebesar 5057.47 U/g.menit. Proses hidrolisis berlangsung dengan menggunakan substrat kacang tanah dan air dengan perbandingan 1:2. Kondisi hidrolisis terbaik untuk menghasilkan pepton kacang tanah dicapai dengan menggunakan enzim papain sebesar 0.4% dengan hidrolisis selama 4 jam pada suhu 55 oC. Pepton yang dihasilkan merupakan produk cair berwarna kuning kecoklatan, supernatan dari proses sentrifugasi. Rendemen proses hidrolisis ini adalah 1.23 ml/g kacang tanah. Kandungan asam amino tertinggi pepton ini adalah asam glutamat. Hasil pengujian pertumbuhan pada Escherichia coli dan Staphylococcus aureus menunjukkan bahwa pepton kacang tanah dapat digunakan sebagai komponen dalam media pertumbuhan bakteri.
Keyword: Escherichia coli, hidrolisis enzimatis, papain, pepton kacang tanah, Staphylococcus aureus

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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