Judul: Aktivitas Enzim Ligninase Isolat Pleurotus spp. Liar Asal Bogor
Abstrak: Jamur pelapuk putih Pleurotus spp. dapat digunakan sebagai agens dalam proses biopulping dan biobleaching pada industri pulp dan kertas untuk mengurangi bahan-bahan kimia yang tidak ramah terhadap lingkungan dan menurunkan energi yang dibutuhkan. Jamur pelapuk putih menghasilkan enzim ligninase yang mampu mendegradasi lignin diantaranya adalah lakase dan peroksidase (lignin peroksidase (LiP) dan manganese peroksidase (MnP)). Penelitian ini bertujuan untuk mendapatkan aktivitas enzim ligninase yaitulakase dan peroksidase (LiP dan MnP) yang dihasilkan oleh Pleurotus sp.1 dan Pleurotus sp.4 pada media malt ekstrak cair dengan penambahan substrat serbuk gergajian kayu sengon.
Keyword: 

Judul: Aktivitas enzim ligninolitik fungi pelapuk putih Omphalina sp. dan pleurotus ostreatus pada limbah lignoselulosa
Abstrak: Fungi Pelapuk Putih (FPP) Omphalina sp. dan Pleurotus ostreatus mampu mendegradasi lignin pada limbah lignoselulosa seperti Tandan Kosong Kelapa Sawit (TKKS) dan bagas tebu dengan memproduksi enzim ligninolitik. Penelitian bertujuan mengoptimumkan produksi enzim ligninolitik oleh Fungi Pelapuk Putih (FPP) pada TKKS dan bagas tebu dengan pemberian suplemen CuSO4, dedak, dan kombinasi CuSO4 dan dedak, serta mengkarakterisasi pH optimum enzim ligninolitik. Aktivitas rata-rata tertinggi enzim lakase ditunjukkan oleh isolat P.ostreatus pada media TKKS, pada perlakuan kontrol sebesar 0,223 U/mL, CuSO4 0,546 U/mL, dan kombinasi CuSO4 dan dedak sebesar 0,626 U/mL, berbeda dengan tiga perlakuan lainnya, pada perlakuan dedak aktivitas rata-rata tertinggi enzim lakase sebesar 0,383 U/mL ditunjukkan oleh isolat P.ostreatus pada media bagas tebu. Aktivitas rata-rata tertinggi enzim lignin peroksidase ditunjukkan oleh isolat P.ostreatus pada media TKKS, perlakuan kontrol sebesar 1,983 U/mL, perlakuan CuSO4, dedak, dan kombinasi CuSO4 dan dedak sebesar 2,198 U/mL, 2,061 U/mL, dan 2,372 U/mL. Aktivitas rata-rata tertinggi enzim mangan peroksidase ditunjukkan oleh isolat P.ostreatus pada media TKKS, perlakuan CuSO4 sebesar 0,872 U/mL, dedak 0,923 U/mL, dan kombinasi CuSO4 dan dedak sebesar 0,877 U/mL, sedangkan pada perlakuan kontrol ditunjukkan oleh isolat P.ostreatus pada media bagas tebu dengan aktivitas rata-rata sebesar 0,643 U/mL.. Aktivitas rata-rata enzim ligninolitik optimum pada pH 5.
Keyword: 

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.
Keyword: