Judul: Potensi ekstrak residu distilasi uap daun Zingiberaceae sebagai antibakteri Streptococcus mutans dan degradator biofilm pada gigi
Abstrak: Tanaman Zingiberaceae biasa digunakan untuk mengobati berbagai penyakit dan sebagai bumbu masakan. Genus yang umum digunakan sebagai obat tradisional ialah Curcuma dan Zingiber. Keduanya berpotensi sebagai antibakteri dan diduga mampu mendegradasi biofilm Streptococcus mutans. Penelitian ini bertujuan menentukan potensi residu distilasi daun Zingiberaceae sebagai antibakteri terhadap S.mutans dan degradator biofilm pada gigi. Daun yang digunakan hasil dari residu distilasi dan diekstraksi dengan sokletasi dan dilanjutkan dengan ekstraksi menggunakan 3 pelarut berbeda (n-heksana, etil asetat, dan metanol). Uji antibakteri dan degradasi biofilm dilakukan menggunakan teknik mikrodilusi dengan pelat 96-sumur steril. Ekstrak metanol temu putih memiliki aktivitas terbaik dengan nilai konsentrasi hambat minimum dan konsentrasi bunuh minimum sebesar 15.6 μg/mL dan aktivitas degradasi biofilm yang baik dengan IC50 15.3 μg/mL. Pada Kromatografi Lapis Tipis bioautografi terdapat 4 spot dan spot yang paling aktif pada Rf 0.90. Terpenoid diduga sebagai senyawa aktif antibakteri dan degradator biofilm.
Keyword: antibacterial, biofilm degradator, Streptococcus mutans, Zingiberaceae

Judul: Potensi minyak atsiri beberapa daun Zingiberaceae sebagai antibakteri Streptococcus mutans dan degradator biofilm pada gigi
Abstrak: Penelitian dilakukan untuk menentukan potensi minyak atsiri daun Zingiberaceae sebagai antibakteri terhadap Streptococcus mutans dan degradator biofilm pada gigi. Minyak atsiri yang digunakan, yaitu Zingiber officinale varietas rubrum, Curcuma domestica, Kaempferia galanga, C. zedoaria, C. aeruginosa, C. xanthorrhiza, Elettaria cardamomum, dan Z. purpureum. Uji antibakteri dan degradasi biofilm dilakukan melalui metode dilusi. Klorheksidin dan obat kumur komersial digunakan sebagai kontrol positif. Rendemen tertinggi dimiliki oleh E. cardamomum (2.43%). Minyak atsiri daun K. galanga, C. aeruginosa, C. domestica, E. cardamomum, dan Z. purpureum berhasil menghambat S. mutans dengan konsentrasi hambat minimum (KHM) 2000 μg/mL. Aktivitas antibakteri dan degradasi biofilm paling baik ditunjukkan oleh E. cardamomum sehingga minyak daun tersebut dianalisis lebih lanjut dengan kromatografi gasspektrofotometer massa dan diuji dengan kromatografi lapis tipis bioautografi. Hasilnya menunjukkan eukaliptol sebagai senyawa utama diduga memiliki aktivitas antibakteri dan aktivitas degradasi biofilm.
Keyword: antibacterial, biofilm degradation, essential oils, Zingiberaceae

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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