Judul: α-Glukosidase Inhibitory Activity of Methanol Extract and Fractionation of Aspergillus oryzae-fermented Gandarusa (Justicia gendarussa Burm. f)
Abstrak: Gandarusa dilaporkan mengandung senyawa metabolit sekunder yang dapat menghambat aktivitas α-glukosidase pada penderita diabetes melitus. Salah satu cara untuk meningkatkan produksi metabolit sekunder dengan metode Solid State Fermentation (SSF) menggunakan Aspergillus oryzae. Penelitian ini bertujuan menentukan aktivitas inhibisi α-glukosidase dari fraksi kromatografi kolom hasil fermentasi gandarusa oleh A. oryzae. Penelitian ini terdiri dari preparasi inokulum A. oryzae, fermentasi gandarusa metode SSF, optimasi pelarut purifikasi, pemisahan ekstrak metanol fermentasi gandarusa metode kromatografi kolom, dan pengujian aktivitas inhibisi α-glukosidase. Hasil penelitian didapatkan kombinasi pelarut etil asetat:n-heksana (4:6) sebagai pelarut optimum. Adapun purifikasi gandarusa memperoleh hasil pemurnian yang terbaik, dengan nilai aktivitas inhibisi α-glukosidase fermentasi gandarusa yang dipurifikasi memiliki nilai persentase lebih tinggi (fraksi 2: 54,91%) dibandingkan dengan tanpa purifikasi (ekstrak kasar: −26,36%). Sementara itu, nilai aktivitas α-glukosidase terhadap kontrol positif (akarbosa) sebesar 48,09%., Gandarusa has been reported to contain secondary metabolite compounds that can inhibit α-glukosidase activity in patients with diabetes mellitus. One way to increase the production of secondary metabolite compounds is the Solid State Fermentation (SSF) method using Aspergillus oryzae. This study aimed to determine the α-glukosidase inhibition activity of the column chromatography fraction of fermented gandarusa by A. oryzae. This research consisted of inoculum preparation of A. oryzae, fermentation of gandarusa using SSF method, purification solvent optimization, separation of methanol extract of gandarusa fermentation using column chromatography method, and α-glucosidase inhibition activity testing. The results showed that ethyl acetate:n-hexane (4:6) solvent combination was the optimum solvent. The purification of gandarusa obtained the best purification results, with the value of α-glukosidase inhibition activity of purified gandarusa fermentation having a higher percentage value (fraction 2: 54,91%) compared to without purification (crude extract: −26,36%). Meanwhile, the α-glukosidase activity value against the positive control (akarbosa) was 48,09%.
Keyword: α-glukosidase, Aspergillus oryzae, fermentation, gandarusa, column chromatography

Judul: Aktivitas Inhibisi α-Glukosidase Hasil Purifikasi Gandarusa dengan Kromatografi Kolom
Abstrak: Gandarusa (Justicia gendarussa Burm. f.) merupakan herbal sumber daya lokal Indonesia yang berpotensi sebagai obat herbal antidiabetes. Penelitian ini bertujuan menentukan aktivitas inhibisi α-glukosidase dari senyawa yang terkandung pada fraksi hasil purifikasi ekstrak metanol gandarusa menggunakan kromatografi kolom. Simplisia gandarusa dimaserasi bertingkat dengan n-heksana, etil asetat, dan metanol. Ekstrak gandarusa difraksinasi dengan kromatografi kolom menggunakan pelarut optimal (etil asetat:n-heksana 4:6 v/v). Ekstrak kasar dan 8 fraksi hasil purifikasi dipekatkan kemudian ditentukan aktivitas antioksidannya dengan menggunakan KLT bioautografi dan aktivitas inhibisi α-glukosidasenya secara in vitro. Hasil penelitian menunjukkan bahwa purifikasi gandarusa menghasilkan fraksi kolom yang memiliki aktivitas antioksidan dan dapat menghambat α-glukosidase lebih baik dibandingkan ekstrak kasar tanamannya. Aktivitas inhibisi α-glukosidase tertinggi dimiliki oleh F2 (IC50 99,34 ppm), lebih tinggi dibandingkan dengan obat komersial akarbosa. Secara keseluruhan, fraksi gandarusa berpotensi untuk dikembangkan lebih lanjut sebagai obat herbal antidiabetes.
Keyword: α-glucosidase, antidiabetic, column chromatography, Justicia gendarussa

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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