Curcumin, an active compounds found in Curcuma domestica Val, exhibits many pharmacological effects. Due to its numerous benefits, pressurized liquid water extraction is gaining many interests from researchers. Response Surface Methodology applied in the optimization study of the pressurized liquid water extraction of curcumin from Curcuma domestica Val. Central Composite Design was applied in the design of this research. The parameter process studied were temperature (130-150 0 C), time (20-40 minutes) and reaction volume (4-6.2 L). The solid-liquid ratio was fixed at a ratio of 1:10, ad the pressure was fixed of 2 bar. Response surface of the pressurized liquid water extraction of curcumin was expressed by a second-order polynomial. The research showed that the model we adequate to predict the pressurized liquid water extraction of curcumin in the range of variables studied in this research. The research showed that temperature was the most influencing variable for pressurized liquid water extraction of curcumin from Curcuma domestica Val. The optimal value of the pressurized liquid water extraction of curcumin was obtained by solving the second-order polynomial regression equation. The curcumin pressurized liquid water extraction was optimum at an extraction temperature of 156.81 0 , extraction time of 46.81 minutes and solvent volume of 6.95L.

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Jahe merupakan salah satu jenis komoditas rempah yang memiliki beragam manfaat dan kegunaan. Jahe dalam bentuk bubuk diminati masyarakat karena lebih praktis dan lebih tahan lama. Salah satu metode pengeringan serbuk jahe yang dipandang tepat untuk diaplikasikan dalam proses produksi serbuk jahe adalah metode pengeringan busa (foam mat drying). Penelitian ini bertujuan untuk mengkaji proses pengeringan busa terhadap jahe dengan menggunakan tween 80 (foam agent) dan maltodekstrin sebagai bahan pengisi untuk membantu mempertahankan konsistensi busa. Proses percobaan menggunakan pengeringan tanpa foam untuk dibandingkan dengan variabel komposisi tween 80 (4%,6%,8%) dan maltodekstrin (10%,15%,20%). Didapatkan hasil perbandingan terbaik pada sampel 4 dengan kadar air 0,07% pada menit ke 120. Hasil percobaan secara keseluruhan sudah memenuhi standar minimal produk makanan yaitu <5%. Kata kunci : Jahe, Foam mat drying, Tween 80, Maltodekstrin

The drugs traditionally used to treat uncomplicated malaria have become ineffective, due to the development of drug resistance. It has led to a widespread promotion of artemisinin-based combination therapy (ACT) as a strategy for effective management of Plasmodium falciparum malaria. The main drawback of the ACTs is their high cost. Hence, many phytoconstituents are currently investigated for their antimalarial activity. One of them is andrographolide of Andrographis paniculata (Burm.f.) Wall. A combination of microwave assisted-extraction and the utilization of hydrotrope as the extraction medium is already proved as a potential safe alternative for the separation of andrographolide. Mathematical models of extraction plays a crucial role in basic research of phytoconstituent separation; they are not yet available for hydrotropic-microwave assisted extraction of andrographolide. Therefore, there is a need to conduct a scientific study in this field. The mathematical model is a useful engineering tool for equipment optimization, simulation, design and control, allowing theoretical description of the process and evaluation of the kinetic constant. The aim of this work was to model the kinetics of hydrotropic-microwave assisted extraction of andrographolide. The kinetics of hydrotropic-microwave assisted extraction of andrographolide was studied for two different powers of the microwave extractor (10 % and 30 %). A second order kinetic model describes the solid liquid extraction process of andrographolide from Andrographis paniculata (Burm.f.) Wall.

The three major lignocellulose components can be transformed into various biomass-derived platform fuels, chemicals, and materials upon pretreatment and chemical upgrading. Lignocellulose pretreatment is an important step to obtain an eco-friendly, economical, and effective biomass utilization process. The combination of microwave heating and hydrotropic pretreatment is considered as a green method of lignocellulose pretreatment. Experimental data and two mechanistic kinetic models of microwave-assisted pretreatment of rice straw are presented. Here, the use of urea solution as the hydrotropic agent was examined to facilitate the degradation of three major lignocellulose components. The first kinetic model assumes that the soluble lignin does not undergo condensation, while the second one assumes that part of the soluble lignin condenses to a solid product. The mechanistic models were validated with a series of experimental data obtained from microwave-assisted hydrotropic pretreatment of rice straw. The results show that both models could generally describe the experimental data well. However, based on the evaluation of the results of the kinetic models, it turned out that the rate of lignin condensation was relatively slow compared to the rate of lignin degradation to soluble lignin (the value of k c is relatively small compared to the value of k l1 ). Hence, the kinetic model with exclusion of lignin condensation is suggested more since it is mathematically simpler. The proposed mechanistic model can also predict the cellulose and hemicellulose dissolution and thereby can be used as a process optimization tool. The microwave-assisted urea-based hydrotropic pretreatment conducted at a solid−liquid ratio of 1:35, a urea concentration of 36.8%, a reaction temperature of 90 °C, and a pretreatment duration of 73.6 min is predicted to give a solid residue with low lignin content and high cellulose content which resulted in a cellulose to lignin ratio of 5.53. Cellulosic biomass characterization revealed that microwave-assisted hydrotropic pretreatment was able to produce higher crystallinity and thermally stable cellulosic biomass.