Judul: Pembuatan bioetanol dari bagas batang sorgum manis melalui proses delignifikasi oleh NaOH
Abstrak: Sweet sorghum bagasse rod including lignocellulosic materials containing lignin, cellulose and hemicellulose that can be used in the manufacture of ethanol. This study aims to stem the production of ethanol from sweet sorghum bagasse. Stages of research consists of preparation of sweet sorghum bagasse rod, pretreatment using NaOCl, delignification with NaOH, saccharification with xylanase and cellulase enzymes and fermentation by Saccharomyces cerevisiae. The parameters in the analysis include the levels of lignin, cellulose and hemicellulose before and after delignification, reduction sugar and ethanol. The results showed that sweet sorghum bagasse rod can be used as raw material in the manufacture of bioethanol, because it is based on data obtained cellulose content before delignification at 23.45% while after delignification, cellulose optimum levels obtained with 8% NaOH concentration is 18.38%. Highest glucose levels obtained from the saccharification at a concentration of 1% cellulase and xylanase 1% at 177%. Highest levels of ethanol during fermentation by S. cerevisiae with a concentration of 2% inoculum were incubated for 6 days is 19.34 %
Keyword: Bogor Agricultural University, Saccharomyces cerevisiae, saccharification, fermentation, ethanol, delignification, cellulose, Bioethanol

Judul: Produksi Bioetanol dari Limbah Biomassa Lignoselulosa Sorgum (Sorghum bicolor L.) melalui Fermentasi Saccharomyces cerevisiae.
Abstrak: Batang sorgum manis termasuk bahan lignoselulosa yang mengandung lignin, selulosa dan hemiselulosa sehingga dapat dimanfaatkan dalam pembuatan etanol. Penelitian ini bertujuan untuk produksi etanol dari limbah lignoselulosa batang sorgum manis. Tahapan penelitian terdiri atas persiapan limbah batang sorgum manis, pengeringan dan pencacahan, hidrolisis dengan asam-basa kuat encer (H2SO4 0.5 % dan NaOH 1%) serta fermentasi oleh S. cerevisiae. Parameter yang dianalisis meliputi kadar glukosa dan xilosa hasil hidrolisis lignoselulosa, kadar etanol dan kadar produk samping berupa asam asetat, asam laktat, dan gliserol. Berdasarkan data yang diperoleh kadar glukosa dari hasil hidrolisis asam lebih besar daripada hidrolisis basa yaitu 5,39 g/L dan xilosa sebesar 12,05 g/L. Kadar etanol paling tinggi selama fermentasi oleh Saccharomyces cerevisiae TKPK 10.5.1 yang diinkubasi selama 2 hari adalah 2,76 g/L. Hasil penelitian menunjukan bahwa limbah lignoselulosa batang sorgum manis dapat dijadikan sebagai bahan baku dalam pembuatan bioetanol.
Keyword: Bioetanol, fermentasi, hidrolisis, lignoselulosa, Saccharomyces cerevisiae

Judul: Exchange Market Pressure and Central Bank Intervention for Three ASEAN Countries
Abstrak: Two of the exchange rate systems which are adopted by many countries are the floating and the fixed exchange rate system. Both the exchange rate systems have different characteristics. Countries that implement fixed exchange rates system tend to set their domestic currency exchange rate at a certain point. On the contrary, countries which implement floating exchange rate system tend to let their domestic currency exchange rate to move flexibly and thus their value will always change according to the demand and supply of the currency in the foreign exchange market. Countries which implement floating exchange rate system are facing the risk of fluctuation in the exchange rate of their domestic currency against foreign currencies. The currency exchange rate fluctuation may be caused by economic problems such as a financial crisis. A country can also be potentially affected by other countries’ earlier financial crisis. This effect could potentially happen if these countries are in the same region, such as ASEAN. The 1997 ASEAN economic crisis was an example of a country’s financial crisis could affect other countries. At that time, some countries such as Indonesia, Malaysia and Thailand had to change their currency exchange rate system from the fixed exchange rate system to the floating exchange rate system due to the high costs which has to be incurred if they were to enforce the fixed exchange rate system. During 2002 until 2012, the domestic exchange rate of Indonesia, Malaysia and Thailand against the U.S. dollar had tended to fluctuate. If the domestic currency exchange rate fluctuated excessively then the central bank would intervene to stabilize the exchange rate in the foreign exchange market. The pressure on domestic currency exchange rate pressures has forced the central bank to intervene. The amount of those pressures can be analyzed by calculating the Exchange Market Pressure (EMP) index. Apart from that, the time when interventions are done by the central bank can be known based on EMP by calculating the Exchange Market Intervention (EMI) index. The purposes of this study were to determine the level of international pressure on the currency exchange market and monetary authorities intervene in three ASEAN countries, as well as to determine the effect of the monetary authorities intervene on the exchange rate of the domestic currency against the U.S. dollar in those three ASEAN countries. Based on the EMP index calculation results which are obtained during 2002 to 2012 period, the exchange rate of Indonesia, Malaysia and Thailand’s domestic currency had always fluctuated and the results of the EMP index indicated that each country were under diverse level of currency exchange rate appreciation and depreciation pressures. Thailand was the country with the highest currency exchange rate pressure compared to Indonesia and Malaysia. The results on the intervention index calculation showed that Indonesia, Malaysia and Thailand have intervention index between zero and one and more than one. We can also see from the intervention index that Indonesia and Thailand implement the controlled floating currency exchange rate instead of the freely floating one. Based on the calculation of the currency exchange rate by comparing
Keyword: exchange rate, exchange market pressure, intervention