Judul: Antioxidant Analysis of Endophytic Fungus Extract of Soursop Leaf Phomopsis sp. on Liver Function of DMBA-Induced Sprague-Dawley Rats.
Abstrak: Penelitian ini bertujuan untuk menentukan efek senyawa 7,12-dimetilbenz(a)antrasena (DMBA) pada tikus betina galur Sprague-Dawley dan efektivitas Phomopsis sp. sebagai antioksidan. Metode penelitian melibatkan pengukuran kadar malondialdehida (MDA), dan aktivitas enzim hati (ALT dan AST). Hasil penelitian menunjukkan bahwa DMBA meningkatkan kadar radikal bebas yang ditandai dengan meningkatnya kadar MDA secara signifikan menjadi 27,25 ± 6,11 nm/g hati (Kontrol negatif), dan terbukti bahwa Phomopsis sp. mampu menurunkan kadar MDA sampai 11,71 ± 1,42 nm/g hati dengan dosis 40mg/kg bb. Aktivitas enzim ALT dan AST juga meningkat walau tidak signifikan pada kelompok yang diinduksi DMBA sebesar 38,89 ± 7,66 U/L dibandingkan Kelompok Normal sebesar 34.97 ± 3.35 U/L . Sementara itu, Phomopsis sp. dosis 40mg/kg bb berbeda signifikan dengan nilai ALT mencapai 67,97 ± 11,79 U/L dan AST mencapai 75,66 ± 1,53 U/L. Namun, pemberian Phomopsis sp. dosis 10mg/kg bb dan 20mg/kg bb dapat menurunkan aktivitas enzim ini. Simpulan penelitian ini menunjukkan bahwa Phomopsis sp. memiliki potensi sebagai antioksidan yang efektif dalam mengurangi stres oksidatif akibat paparan DMBA., This study aimed to determine the effects of 7,12-dimethylbenz(a)anthracene (DMBA) compound on female Sprague-Dawley rats and the effectiveness of Phomopsis sp. as an antioxidant. The research methods involved the measurement of malondialdehyde (MDA) levels, and liver enzyme activities (ALT and AST). The results showed that DMBA increased the levels of free radicals characterized by increasing MDA levels significantly to 27,25 ± 6,11 nm/g liver from the Negative Control, and it was proven that Phomopsis sp. was able to reduce MDA levels to 11,71 ± 1,42 nm/g liver at a dose of 40mg/kg bw. ALT and AST enzyme activities also increased although not significantly in the DMBA-induced group at 38,896 ± 7,661 U/L compared to the Normal Group at 34,96 ± 3,35 U/L . Meanwhile, Phomopsis sp. with 40mg/kg bw dosage was significantly different with values reaching 67,97 ± 11,79 U/L and AST reaching 75,66 ± 1,53 U/L. However, the administration of Phomopsis sp. 10mg/kg bw and 20mg/kg bw can reduce the activity of these enzymes. The conclusion of this study shows that Phomopsis sp. has the potential as an effective antioxidant in reducing oxidative stress due to DMBA exposure.
Keyword: MDA, ALT, AST, DMBA, Phomopsis sp.

Judul: Analysis of the Antioxidant Potential of Phomopsis sp. on Kidney Function in Sprague-Dawley Rats Induced with 7,12- Dimethylbenz(a)anthracene
Abstrak: Phomopsis sp. diketahui memiliki aktivitas antioksidan yang kuat dalam melindungi sel dari kerusakan yang disebabkan oleh radikal bebas. Namun, kajian terkait potensi antioksidan Phomopsis sp. terhadap kadar ureum, kreatinin, dan MDA (Malondialdehid) ginjal secara in vivo pada tikus Sprague-Dawley betina yang diinduksi kanker payudara belum dilakukan. Penelitian ini bertujuan menganalisis potensi antioksidan ekstrak Phomopsis sp. terhadap fungsi ginjal dengan parameter kadar ureum, kreatinin, dan MDA ginjal secara in vivo pada tikus Sprague-Dawley betina yang diinduksi kanker payudara. Metode penelitian meliputi ekstraksi senyawa bioaktif Phomopsis sp., pengkondisian hewan coba, induksi DMBA pada tikus, pembuatan serum darah untuk uji kreatinin dan urea, nekropsi dan pengambilan organ ginjal untuk uji MDA ginjal, serta analisis data menggunakan one-way ANOVA. Hasil penelitian menunjukkan ekstrak Phomopsis sp. dosis 20 mg/Kg BB merupakan dosis terbaik dengan nilai konsentrasi MDA (2.974 ± 0.820 nmol/gr), kadar kreatinin (0.417 ± 0.144 mg/dL), serta kadar urea (18.750 ± 1.250 mg/dL). Ekstrak Phomopsis sp. dosis 20 mg/Kg BB memiliki potensi antioksidan yang kuat dengan menurunkan nilai MDA, kreatinin, dan urea secara signifikan. Kadar MDA, kreatinin, dan urea pada ginjal menunjukkan perubahan yang signifikan (p<0.05), Phomopsis sp. is known to have strong antioxidant activity in protecting cells from damage caused by free radicals. However, studies related to the antioxidant potential of Phomopsis sp. on urea, creatinine, and kidney MDA (Malondialdehyde) levels in vivo in female Sprague-Dawley rats induced with breast cancer have not been conducted. This study aimed to analyze the antioxidant potential of Phomopsis sp. extract on kidney function with parameters of urea, creatinine, and kidney MDA levels in vivo in female Sprague-Dawley rats induced with breast cancer. The research methods include the extraction of bioactive compounds from Phomopsis sp., conditioning of experimental animals, induction of DMBA in rats, preparation of blood serum for creatinine and urea tests, necropsy and kidney organ collection for kidney MDA tests, and data analysis using one-way ANOVA. The results of the study showed that Phomopsis sp. extract at a dose of 20 mg/kg BW was the best dose with MDA concentration values (2.974 ± 0.820 nmol/g), creatinine levels (0.417 ± 0.144 mg/dL), and urea levels (18.750 ± 1.250 mg/dL). Phomopsis sp. extract at a dose of 20 mg/kg BW had strong antioxidant potential by significantly lowering MDA, creatinine, and urea values. Kidney MDA, creatinine, and urea levels showed significant changes (p<0.05).
Keyword: Antioksidan, in vivo, kreatinin, MDA, Phomopsis sp, urea

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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