Judul: Formula Campuran 3 Daun Tanaman Obat sebagai Penghambat Tirosinase serta Sidik Jari Kromatogramnya
Abstrak: Potensi formula campuran 3 daun tanaman obat (A, B, dan C) dalam mengurangi hiperpigmentasi kulit ditetapkan berdasarkan aktivitas inhibitor tirosinase dan antioksidan. Daun diekstraksi dengan maserasi menggunakan etanol 50%. Ketiga ekstrak tanaman dikombinasikan berdasarkan bobot menggunakan simplex centroid design. Formula diuji kadar fenolik total, flavonoid, aktivitas inhibitor tirosinase, dan antioksidan 2,2-difenil-1-pikrilhidrazil (DPPH). Ekstrak tunggal daun A menunjukkan aktivitas terbaik sebagai inhibitor tirosinase (IC50 monofenolase 214.39 μg/mL; IC50 difenolase 274.40 μg/mL) dan antioksidan (IC50 56.94 μg/mL). Ada 4 noda aktif dengan substrat L-tirosina dan 3 noda aktif dengan substrat 3,4-dihidroksifenilalanina (L-DOPA) yang diperoleh dari pola sidik jari kromatografi lapis tipis ekstrak tunggal daun A. Sidik jari ekstrak tersebut dianalisis menggunakan etil asetat:kloroform sebagai fase gerak terbaik.
Keyword: antioksidan, hiperpigmentasi, inhibitor tirosinase, sidik jari

Judul: Formulasi Campuran Ekstrak Etanol Sirih Merah, Kayu Manis, dan Jahe Merah sebagai Antioksidan dengan Desain Simplex-Centroid
Abstrak: Tanaman herbal menjadi subjek yang terus diteliti di Indonesia mengingat signifikansi manfaat kesehatannya. Fokus penelitian ini bertujuan melakukan formulasi dari sirih merah, kayu manis, dan jahe merah menggunakan rancangan campuran simplex-centroid dengan optimasi rancangan campuran I-optimal untuk mengujikan respon kandungan total fenolik dan kapasitas antioksidannya. Simplisia dari ketiga sampel diekstraksi menggunakan metode maserasi dengan pelarut etanol 70% (v/v). Design-Expert 12 digunakan untuk formulasi dengan model simplex-centroid design dan optimasi rancangan I-optimal. Pengujian in-vitro berupa metode kolorimetri untuk uji total fenolik dan uji kapasitas antioksidan. Hasil pengujian terhadap ketujuh formula menunjukkan kandungan total fenolik tertinggi dimiliki oleh formula ekstrak tunggal kayu manis (F2) sebesar 506,67 ± 12,30 mg GAE/g bobot kering sedangkan kapasitas antioksidan tertinggi oleh campuran kayu manis dan jahe merah (F6) sebesar 391,21 ± 6,21 µmol TE/g bobot kering. Solusi optimasi dari model ini yaitu 99,25% proporsi kayu manis dan 0,75% untuk jahe merah dengan nilai desirability 0,87. Campuran terbaik yang dapat dirumuskan dari ketujuh formula berdasarkan metode penelitian ini yaitu campuran biner antara kayu manis dan jahe merah (F6)., Herbal plants are natural objects that have been researched in Indonesia due to their significant health benefits. This research aimed to formulate three herbal plants, namely red betel, cinnamon and red ginger using a simplex-centroid mixture design with I-optimal optimization design to measure the response of total phenolic content and antioxidant capacity. Maceration was applied with 70% (v/v) ethanol solvent, while the Folin-Ciocalteu method was carried out for total phenolic content assay and DPPH method for antioxidant activity assay. The formulation was defined using the Design-Expert 12 software with simplex-centroid design model and I-optimal design. The results from the seven formulas of the three herbal plants formulation showed that the highest total phenolic content was possessed by the formula with pure extract of cinnamon, amounting to 506.67 ± 12.30 mg GAE/g dry weight.Meanwhile, the highest antioxidant activity was obtained by mixture of cinnamon and red ginger, yielding 391.21 ± 6.21 µmol TE/g dry weight of extract.The optimization solution for this model was 99.25% proportion of cinnamon and0.75% of red ginger with a desirability value of 0.87. The best mixture overall amongst the formulas was the binary mixture of cinnamon and red ginger.
Keyword: Antioksidan, Fenolik, antioxidant, Formulasi, Optimasi, Simplex-centroid design, formulation, optimization, simplex-centroid design, phenolic compound

Judul: Pengukuran Kecepatan Gelombang Seismik Laut 2D menggunakan Prestack Time Migration dengan Metode Kirchhoff
Abstrak: Seismic method is a method used in geophysics to study the structure of earth surface and below using sounds. Seismic waves are emitted by the transmitter into the sea to the subsurface ocean floor. Reflected wave is returned subbottom to the hydrophone and contains information on the elastic parameters of the subbottom. The method used in this study is using the Prestack Time Migration (PSTM) with the Kirchhoff method has the advantage to increase the Signal/Noise data and be able to improve data quality including time, angles, and distances. This study was conducted to analyze the speed of default parameters and the root mean square (rms) using Prestack Kirchhoff Time Migration method. Cross-sectional results of the two treatments were applied in seismic data line 13-1 in the Gulf of Bone waters, South Sulawesi. In the seismic section are sequence boundaries of toplap, downlap, normal and reverse faults event. Based on the results obtained, cross prestack time migration using the rms velocity analysis (picking velocity) gives better results compare to the cross section of prestack time migration using default parameters.
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