Judul: Identifikasi Metabolit Akar Sidaguri (Sida rhombhifolia L.) Berdasarkan Waktu Tanam Berbeda Menggunakan LC-MS/MS
Abstrak: Sidaguri (Sida rhombifolia L.) merupakan salah satu jenis tanaman yang telah digunakan sebagai obat tradisional dengan berbagai khasiat untuk mengobati banyak penyakit karena adanya kandungan metabolit bioaktif di dalamnya. Kandungan metabolit di dalam akar tanaman sidaguri dipengaruhi oleh beberapa faktor, salah satunya adalah usia tanam. Penelitian ini bertujuan mengidentifikasi senyawa dan mengelompokkan ekstrak akar sidaguri berdasarkan waktu tanam berbeda menggunakan data hasil ekstraksi yang diperoleh dari LC-MS/MS yang dikombinasikan dengan kemometrik. Sebanyak 19 senyawa teridentifikasi dan terkonfirmasi pada ekstrak akar tanaman sidaguri dengan usia tanam 3, 4, dan 5 bulan. Senyawa-senyawa tersebut termasuk ke dalam golongan fenolik, alkaloid, steroid, flavonoid, kumarin, asam benzoat dan asam lemak. Berdasarkan hasil pengelompokkan dengan PCA menggunakan variabel luas puncak 19 senyawa metabolit yang teridentifikasi, ekstrak sidaguri mengelompok sesuai usia tanam masing-masing dengan total plot skor sebesar 68%., Sidaguri (Sida rhombifolia L.) is a type of plant that has been used as a traditional medicine with various properties for treating many diseases because of the bioactive metabolites it contains. The metabolites content in the roots of the sidaguri were affected by some factors, such as cultivation age. This research aims to identify compounds and classify sidaguri root extracts based on different planting times using extraction data obtained from LC-MS/MS combined with chemometrics.. A total of 19 compounds were identified and confirmed in the root extract of the sidaguri plant with a planting age of 3, 4 and 5 months. These compounds belong to the phenolic, alkaloids, steroids, flavonoids, coumarins, benzoic acid and fatty acids groups. Based on the results of grouping using PCA using the peak area variable of 19 identified metabolite compounds, sidaguri extracts were grouped according to their respective planting ages with a total score plot of 68%.
Keyword: metabolit, metabolit sekunder

Judul: Metabolite Profiling of Leaves Extracts of Sida rhombifolia L. with Different Planting Age Using Liquid Chromatography-Mass Spectrometry
Abstrak: Sidaguri (Sida rhombifolia L.) adalah tanaman obat yang diyakini khasiatnya oleh masyarakat sebagai obat asam urat, antihipertensi, dan lain sebagainya. Penelitian ini bertujuan mengidentifikasi komposisi metabolit bioaktif daun sidaguri. Analisis ekstrak daun sidaguri diklasifikasikan berdasarkan umur tanam tiga, empat, dan lima bulan menggunakan kromatografi cair-spektrometri massa (LC-MS/MS) dan dikelompokan menggunakan analisis komponen utama (PCA). Kromatogram LC-MS/MS diolah menggunakan perangkat lunak Thermo Scientific Xcalibur 4.2 dan Compound Discoverer 3.2. Analisis multivariat menggunakan perangkat lunak The Unscrambler X 10.4. Sebanyak 36 metabolit berhasil teridentifikasi dalam ekstrak. Metabolit tersebut termasuk dalam golongan alkaloid, asam fenolat, flavonoid, kumarin, steroid, dan golongan lain. Ekstrak daun sidaguri terkelompok ke dalam kelasnya masing-masing, yaitu umur tanam 3, 4, dan 5 bulan dengan total varians 77%., Sida rhombifolia L. (sidaguri) is a medicinal plant that is believed to be useful by the community as a gout drug, antihypertensive, and so on. This study aims to identify the composition of bioactive metabolites of sidaguri leaves. Analysis of sidaguri leaf extract was classified based on the planting age of three, four, and five months using liquid chromatography-mass spectrometry (LC-MS/MS) and grouped using principal component analysis (PCA). The LC-MS/MS chromatograms were processed using Thermo Scientific Xcalibur 4.2 and Compound Discoverer 3.2 software. Multivariate analysis using The Unscrambler X 10.4 software. A total of 36 metabolites were identified in the extract. These metabolites are included in the group of alkaloids, phenolic acids, flavonoids, coumarins, steroids, and other groups. Sidaguri leaf extracts were grouped into their respective classes, namely 3, 4, and 5 months of planting age with a total variance of 77%.
Keyword: LC-MS/MS, metabolit sekunder, PCA, Sida rhombifolia L., LC-MS/MS, PCA, Sida rhombifolia L., secondary metabolites

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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