Judul: Aktivitas Antibakteri dan Sediaan Masker Peel Off Berbahan Spirulina platensis terhadap Bakteri Propionibacterium acne.
Abstrak: Spirulina platensis merupakan mikroalga kelompok cyanobacteria yang mengandung senyawa aktif dan berpotensi sebagai antibakteri. Tujuan penelitian ini yaitu menentukan aktivitas antibakteri terhadap P. acne dari ekstrak S. platensis kultur dan komersial, serta sediaan masker peel off yang mengandung ekstrak dan biomasa S. platensis. Tahapan penelitian meliputi kultivasi, pemanenan S. platensis, ekstraksi senyawa aktif, dan aplikasi S. platensis sebagai sediaan masker peel off berbahan polivinil alkohol, hydroxy propyl methyl cellulose, metil paraben, gliserin serta analisis aktivitas antibakteri. Kultivasi S. platensis menggunakan media organik. Biomasa S. platensis diekstraksi menggunakan etanol PA 96%, selanjutnya dianalisis fitokimia. Analisis aktivitas antibakteri dilakukan dengan ekstrak S. platensis dan sediaan masker peel off. Aktivitas antibakteri ekstrak S. platensis hasil kultur dengan konsentrasi 2 mg/mL, 4 mg/mL dan 8 mg/mL berturut-turut yakni 4.63±0.35 mm, 8.81±0.08 mm, 9.56±0.26 mm, sedangkan aktivitas antibakteri dalam sediaan masker peel off terhadap bakteri P. acne yakni 10±0.35 mm.
Keyword: antibakteri, organik, Propionibacterium acne, Spirulina platensis

Judul: Antioxidant Activity of Spirulina platensis During Fermentation Using Lactic Acid Bacteria From Bekasam
Abstrak: Spirulina platensis merupakan mikroalga hijau kebiruan jenis cyanobacteria yang memiliki aktivitas antioksidan. Lactobacillus plantarum SK(5) dan Pediococcus pentosaceus BP(20) bersifat sebagai probiotik dan dapat digunakan secara langsung dalam makanan fermentasi. Penelitian ini bertujuan menentukan karakteristik kimiawi, mikrobiologis, dan aktivitas antioksidan S. platensis selama fermentasi menggunakan bakteri asam laktat (BAL) L. plantarum SK(5) atau P. pentosaceus BP(20). Penelitian ini terdiri atas 3 tahap yaitu kultivasi dan pemanenan biomassa S. platensis, penyiapan kultur starter SK(5) dan BP(20), dan fermentasi spirulina menggunakan starter BAL asal bekasam selama 72 jam inkubasi. Spirulina hasil kultivasi dapat dipanen pada hari ke-14. Spirulina fermentasi mengalami penurunan pH selama 48 jam dan peningkatan pada jam ke-72, serta peningkatan total asam tertitrasi (TAT) dan total BAL selama 48 jam kemudian penurunan pada jam ke-72. Peningkatan total fenol dan aktivitas antioksidan pada spirulina fermentasi dengan kultur BP(20) mencapai 25,43% dan 56,77% selama 48 jam, sedangkan peningkatan total fenol dan aktivitas antioksidan dengan kultur SK(5) mencapai 117,73% dan 188,18% selama 72 jam., Spirulina platensis is cyanobacteria (blue-green algae) that has antioxidant activity. Lactobacillus plantarum SK(5) and Pediococcus pentosaceus BP(20) that as probiotics and can be used directly in fermented foods. This study aimed to determine the chemical, microbiological, and antioxidant activity of S. platensis during fermentation using LAB L. plantarum SK(5) and P. pentosaceus BP(20). The procedure of this study consist of 3 stages, namely culturing of S. platensis, the preparation culture starter of SK(5) and BP(20), and fermentation of spirulina using LAB from bekasam for 72 hours. The spirulina culture was harvested on the 14th day. Fermented spirulina decreased in pH for 48 hours and increased at 72 hours, and increased TAT and LAB for 48 hours then decreased at 72 hours. The increase in total phenol and antioxidant in fermented spirulina with BP(20) reached 25,43% and 56,77% for 48 hours, while the increase in total phenol and antioxidant with SK(5) reached 117,73% and 188,18% for 72 hours.
Keyword: antioxidant, fermented spirulina, lactic acid fermentation, Lactobacillus plantarum SK(5), Pediococcus pentosaceus BP(20)

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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