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"In this volume, Prof. Ye and his coworkers propose and review the concept of nano-bio probe design for biochemical analysis. A unique biochemical analysis technology based on fluorescence polarization enhanced by nanoparticles is described here with successful applications in environmental monitoring, rapid and sensitive sensing protease activity and high-throughput screening of inhibitors. Furthermore, they introduce a versatile molecular beacon (MB)-like probe for the multiplex sensing of targets such as sequence-specific DNA, protein, metal ions and small molecule compounds based on the self-assembled biomolecule-graphene conjugates. Besides, some colorimetric and luminescence probes utilizing metal nanoparticles for biochemical applications are also presented, such as chiral enantiomer discrimination and separation, environmental monitoring, clinic diagnosis and etc."

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Penelitian ini menawarkan pengujian dan evaluasi dari pengaplikasian pengendali nonlinear model predictive control (NMPC) konvensional dan economic NMPC (E-NMPC) pada sistem reaktor biokimia dengan laju pertumbuhan monod dan penghambat substrat. Tujuan utama pengendalian dengan NMPC adalah optimisasi teknis yaitu dengan meminimalisir deviasi dari nilai konsentrasi biomassa dalam reaktor dengan nilai yang diinginkan. Selain itu, tujuan utama pengendalian dengan E-NMPC adalah optimisasi ekonomi dengan mengoptimisasi produksi biomassa yang dihasilkan reaktor. Variabel yang dikendalikan (CV) adalah konsentrasi biomassa dalam reaktor, sedangkan variabel yang dimanipulasi (MV) yang juga menjadi variabel keputusan pada komponen optimisasi pengendali adalah laju dilusi. Dilakukan identifikasi sistem serta formulasi algoritma dan optimisasi pengendali E-NMPC. Penyetelan pengendali NMPC dan E-NMPC dilakukan dengan fine tuning terhadap parameter-parameter tuning pengendali. Pengendali yang telah disetel disimulasikan pada perangkat lunak optimisasi paralel dengan fine tuning dari pengendali E-NMPC. Untuk menguji performa pengendali, diberikan gangguan step pada konsentrasi substrat umpan untuk mengamati respon pengendali terhadap gangguan tersebut. Parameter utama yang akan dievaluasi untuk meninjau kinerja pengendali adalah besar fungsi objektif ekonomi. Disamping itu, ditinjau juga profil MV, ISE dari CV, serta waktu komputasi pengendali. Hasil simulasi menunjukkan bahwa skema pengendalian dengan NMPC konvensional mampu menjaga dan mengubah CV ke nilai yang diinginkan. Selain itu, skema pengendalian dengan E-NMPC memiliki produktivitas berupa produksi kumulatif biomassa yang lebih tinggi daripada skema pengendalian dengan NMPC konvensional, namun memiliki waktu komputasi yang jauh lebih lama.

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This research proposes an examination and evaluation on the application of conventional nonlinear model predictive control (NMPC) and economic NMPC on biochemical reactor system with monod and substrate inhibition growth kinetics. The NMPC controller’s main objective is technical optimization which minimizes the controlled variable deviation from a desired set point, whereas the E-NMPC controller’s main objective is economical optimization which maximizes the cumulative biomass production of the reactor. The controlled variable for this research is the biomass concentration insisde the reactor, whereas the manipulated variable, which also acts as a decision variable for controller optimization, is the dilution rate. Identification of the system is initially done along with formulation of the control algorithm and optimization problem statement for the E-NMPC controller. Tuning of the conventional NMPC and E-NMPC controller is done by fine tuning of the tuning parameters. A step disturbance of feed substrate concentration is used to test the controllers‘ performance. Main evaluation of the controllers‘ performance will be based on economic cost function. Other parameters that will be evaluated are the MV profile, ISE of the CV, and controllers‘ computation time. Result shows that the conventional NMPC schemes are able to bring or maintain the controlled variable to a desired set point. However, the ENMPC scheme outperform the conventional NMPC in cumulative biomass production along the simulation period at the cost of higher computational time.

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"Thionic Fluvisols soil in Southern Vietnam is like typical acid sulfate soil in the tropics and is severely polluted due to human activities. Salinity intrusion and industrial wastewater contamination are the main cause of environmental degradation in soil ecosystem. This research was aimed to determine a link between biochemical soil properties and land use types to provide suitable solutions for afforestation and soil restoration. Soil sampling was conducted in five different land use types at four soil layers (O, AB, Bj and Cp). The five land use types were sugarcane crop; Melaleuca plantation; 2-year Acacia plantation; 5-year Acacia plantation; and control (grass-covered land). The results showed that soil in those five land use types were very acidic (pH ≤ 4) having poor-nutrient condition with  range of  orthophosphate  content of 378 - 640 mg/kg, N-NH4  of 586 - 999 mg/kg and N-NO3 of 830 - 1,112 mg/kg. Concentration of toxic ions was very high with large variation among land use types and soil depths i.e. 1,799 – 12,403 mg SO42-/kg; 22 - 1,645 mg exchangeable Fe/kg and 34 - 88 mg Al3+/kg soil. The lowest concentration of exchangeable Fe3+ and SO42- ions were found in sugarcane and Melaleuca plantations, respectively. Twenty-three sulfur-oxidizing bacteria and two iron-oxidizing bacteria were identified. All these bacteria were initially identified as Thiobacillus sp. Sugarcane and Melaleuca plantations exhibited the most diverse Thiobacillus species which linked to reduction of exchangeable Fe and SO42- concentrations in these two land use types. This study indicated that Thiobacillus sp. could grow well in the Thionic Fluvisols. It is proposed that Melaleuca and sugarcane species could reduce iron and sulfur contents in Thionic Fluvisols in the tropics"

"Senyawa tanin merupakan salah satu jenis senyawa polifenol yang memiliki aktivitas inhibisi terhadap enzim xanthine oxidase. Enzim ini merupakan senyawa yang berperan dalam pembentukan asam urat dalam tubuh. Adanya overproduction atau underexcretion dari asam urat dapat menyebabkan timbulnya keadaan hiperurisemia yang mengakibatkan penyakit pirai atau encok. Penelitian ini bertujuan untuk mengkaji pengaruh variasi pelarut (aseton 70%, etanol 70%, dan akuades) terhadap ekstraksi senyawa tanin dengan metode sonikasi, serta aktivitas inhibisi ekstrak tanin terhadap enzim xanthine oxidase. Proses ekstraksi yang dilakukan terhadap daun putri malu menghasilkan ekstrak kasar terbanyak dengan pelarut akuades, yaitu sebesar 3,9% massa. Aktivitas inhibisi tertinggi juga dihasilkan oleh ekstrak kasar akuades, yaitu sebesar 24,6% yang berkorelasi dengan konsentrasi senyawa tanin sebesar 2,07 mg/g.

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Tannin is one of the polyphenolic compound that exhibits inhibitory activity to xanthine oxidase enzyme. This enzyme plays an important role in the formation of uric acid in the body. Any overproduction or underexcretion of uric acid may lead to hyperuricemic condition that will results in gout.

This study is aimed to assess the effect of solvent variation (70% acetone, 70% ethanol, and water) on tannin extraction with sonication method, as well as the extract's inhibitory activity against xanthine oxidase enzyme.

The extraction process performed on the leaves of Mimosa pudica results in the highest yield extract from water solvent, which is 3.9% weight percentage. The highest inhibitory activity is also generated by the crude water extract, which is 24.6%, correlating with a tannin concentration of 2.07 mg/g."

"ABSTRAKPerkembangan industri dan perekonomian, khususnya di Indonesia, memerlukan sebuah sumber energi yang aman dan dapat berlangsung terus menerus. Renewable diesel, generasi kedua dari perkembangan teknologi biodiesel, menggunakan bahan dasar berupa minyak nabati yang mudah didapat dan dapat dihasilkan terus menerus serta ramah lingkungan. Proses pembuatan Renewable diesel ini menggunakan metode hydroprocessing. Dengan menggunakan program simulasi, penelitian ini menghasilkan profil yield, kandungan yang ada pada renewable diesel, konsumsi hidrogen, dan juga selektivitas reaksi. Simulasi berdasarkan data sekunder dan menggunakan katalis Co-Mo/Al2O3. Hasil simulasi menunjukkan bahwa produksi renewable diesel dari minyak jarak pagar pada suhu 350oC-360oC, LHSV 4/jam, rasio hidrogen dengan umpan sebesar 5;1,dan tanpa menggunakan proses hidroisomerisasi berlangsung menghasilkan yield yang optimal pada tekanan 50 bar, sementara untuk produksi renewable diesel dari minyak kelapa sawit dengan kondisi operasi yang sama menghasilkan yield yang optimal pada tekanan 40 bar. Komponen yang terkandung pada renewable diesel yang dihasilkan adalah komponen linear parafinik C15 – C18, dengan mayoritas komponen yang terkandung adalah C17. Pada simulasi ini, jalur reaksi yang lebih banyak dilalui adalah jalur reaksi dekarboksilasi dan dekarbonilasi dibandingkan dengan jalur reaksi hidrodeoksigenasi.

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ABSTRACTIndustrial development nowadays, especially in Indonesia, needs a new energy source that safe, clean, and sustainable. Renewable diesel, second generation of biodiesel technology development, is based on vegetable oil that can be easily obtained, sustainable, and environmentally safe. Production process of renewable diesel is using the hydroprocessing method, in which triglyceride from vegetable oil is contacted and reacted with hydrogen to produce hydrocarbons. With simulation program, this research results in renewable diesel yield profile, renewable diesel yield components, hydrogen consumptions, side products, and reaction selectivity. Simulation is based on secondary data that has been authented in laboratory, using the Co-Mo/Al2O3 catalyst. This simulation result that with jatropha curcas oil, in temperature range of 350oC-360oC, LHSV 4/h, hydrogen ratio of 5;1, and without hydroisomerization process, the yield is optimum in pressure of 50 bar, meanwhile with the same operation conditions, the yield of renewable diesel from palm oil is optimum in 40 bar. The component that the renewable diesel contains ranged from n-C15 to n-C18, with the most component available is C17.. In this simulation, the most reaction pathway passed is decarboxylation and decarbonylation reaction, instead of hydrodeoxygenation reaction."

"This book aims to disseminate the most current advances in the biotechnological production of D-xylitol and its applications in medical and health care. This book also provides essential information on hemicellulose hydrolysis to recover D-xylose, detoxification of hemicellulose hydrolysates, and improved fermentation methods for increased D-xylitol production. The highlights of strain improvement to increase the D-xylitol titers and downstream recovery of D-xylitol are also discussed in several sections. The current applications of D-xylitol in medical and health care have been used to justify the cost incurred for setting up the demonstration plant for D-xylitol production in the market. "