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"Focused manuscript on the potential use/role of miRNAs in bioprocessing, specifically the production of complex proteins in mammalian cells. With that in mind I propose a draft list of topics/chapters along the following lines, intro on CHO/bioprocessing/engineering challenges to set scene, genomic organization, biogenesis and mode of action, Identifying miRNA targets, computational prediction, transcriptomics, proteomices, UTR analysis, etc., miRNA expression in Chinese hamster ovary cells, miRNAs as engineering targets: pathway manipulation to impact bioprocess phenotypes, miRNAs as biomarkers, detection methods : northern, PCR, hybridization arrays, next gen seq, manipulation of expression in cultured cells : transient/stable disregulation, knockout."

"Xylitol is a sugar alcohol used as a sweetener in the food industry. Xylitol can be produced from D-xylose using a fermentation process, but it then needs to be separated from the other components of the fermentation broth (e.g., metabolic products, residual substances, biomass cells, and mineral salts), before being purified as xylitol crystals. Therefore, to obtain high purity xylitol, various separation processes are required. One very promising downstream processing method is membrane separation. This study evaluated membrane-based processes for the separation of biomass cells and other impurities, determined the concentration of xylitol produced from Debaryomyces hansenii yeast fermentation broth, and proposed a polysulfone ultrafiltration (UF) membrane for biomass-cell separation followed by polyamide nanofiltration (NF) to remove low-molecular-weight compounds (e.g., acetic acids) from sugars. The effects of operating pressure were examined using a fermentation broth model solution. The results showed that a higher pressure caused a higher permeate flux; however, the permeate flux’s rate flow decreased over time due to concentration polarization, and fouling in the UF and NF membranes. Nevertheless, at all pressures, UF achieved a 99% rejection of biomass cells. In addition, microscope analysis showed that no biomass cells were detected in the permeates of UF. The resulting NF concentrates revealed high xylitol retention and a beneficially lower concentration of acetic acids. The operating pressures of the UF test conditions were 1 barg and 1.5 barg, illustrating that, at a pressure of 5.5 barg, the experiments achieved reasonably high xylitol retention (above 90%) indicating negligible losses of sugar in the permeate port. Moreover, this was proven to be a feasible way to concentrate xylitol up to three times from the initial concentration of the model fermentation broth (MFB). Therefore, the results demonstrated that a two-stage combination of UF and NF is a promising system for the downstream processing of microbial xylitol production."

"Cyclodekstrin glucanotranferase (CGTase) merupakan enzim yang mengkatalis produksi cyclodekstrin (CD). Penelitian ini menggunakan satu enzim CGTase komersial (Toruzyme M) yang dihasilkan secara rekayasa genetika menggunakan bakteri Bacillus yang telah disisipkan gen GTase dari bakteri termofilik Thermoanaerobbacter. Walaupun enzim in dapat menghasilkan alpa, beta, dan gamma siklodekstrin (a-CD, 0-CD, ^-CD), namun beta siklodekstrin merupakan produk terbesar. Hasil penelitian memperlihatkan bahwa reaksin enzim CGTase ini dengan pati sagu mentah sangat berbeda jika menggunakan pati sagu tergelatinkan. Temperatur anneling dan temperatur reaksi enzimatik dhetepkan pada 65°C. Kondisi optimum diperoleh pada pH 9 (bufer glisin-NaOH 0.05M), 15% (b/v) pati sagu dan 0.5% konsentrasi enzim. Total siklodekstrin maksimum (13.17 g/L) diperoleh selama 4 jam pada kelajuan agitasi 200 rpm.dengan perbandingan produk adalah 28%: 64%: 8% masing-masing untuk or-CD: /?-CD: y-CD. Adanya CuSO4, FeSO4 and Co(N03)2 didalam substrat mampu menghambat aktivitas enzim secara keseluruhan sedangan pemberian n-pentene dan etanol akan menghasilkan a-CD sebagai produk utama. Nilai Kmax dan Km CGTase Toruzyme?adalah 0.09 s /?-CD/min and 16.695 %(w/v), secara berurutan.

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Cyclodextrin glucanotransferase (CGTase) is (he enzyme catalyzing the production of cyclodextrin (CD). This study was conducted using a commercial CGTase enzyme (ToruzymeT ) produced from genetically modified strain of Bacillus carrying the CGTase gene of Thermoanaerobbacter. Although this enzyme catalyses the formation of alpha, beta and gamma cyclodextrin from starch but beta-cyclodextrin is the major product. The result showed that the reaction behavior of the enzyme on ungelatinized sago starch was markedly different when compared with its reaction to gelatinized starch. Ungelatinised sago starch was annealed and reacted at 6S°C. The optimum condition for the reaction occurred at pH 9 (0.05M Glycine-NaOH buffer) with concentration enzyme and sago starch was 0.5%(v/v)and 15 %(w/v), respectively. The highest amount of total cyclodextrin (13.17 g/L) was produced when the reaction mixture was agitated at 200 rpm for 4 hours consisting of a-CD: /J-CD: y-CD at ratios of 28: 64: 8. The CGTase lost almost all its dextrinizing activity in the presence CuSO4, FeSO4 and Co(NO3)2 in substrate. Addition of n-pentane and ethanol to the reaction mixture, shifted the reaction toward an increased of yield of a-cyclodextrin and eventually becoming the main product of the reaction. The Kmax and Km value of CGTase Toruzyme? were 0.09 g /?-CD/min and 16.695 %(w/v), respectively."

"Clean, safe and sustainable energy sources must be found to minimize all side-effects of fossil fuel consumption. Second generation bioethanol possesses a great potential as an alternative energy source especially in the transportation sector. In this study, rice straw was selected to be studied as a conversion of potential lignocellulosic biomass into bioethanol. Firstly, rice straw was processed with mechanical pretreatment using a home blender, followed by acid pretreatment using 2.0 M sulphuric acid (H2SO4) at 90oC for 60 minutes. The glucose yield was found to be 9.71 g/L. Then, rice straw pretreated with acid was hydrolyzed using 24 mg of cellulase from Tichoderma Ressei ATCC 26921 over a 72-hour duration, which yielded a total glucose count of 11.466 g/L. After fermentation with Saccharomyces cerevisiae, it was found that by combining enzymatic hydrolysis with acid pretreatment yielded a higher ethanol content after fermentation (0.1503% or 52.75% of theoretical value) compared to acidic pretreatment alone (0.013% or 11.26% of theoretical value)."

"Understanding the sustainable use of energy in various processes is an integral part of engineering and scientific studies, which rely on a sound knowledge of energy systems. Whilst many institutions now offer degrees in energy-related programs, a comprehensive textbook, which introduces and explains sustainable energy systems and can be used across engineering and scientific fields, has been lacking. Energy : production, conversion, storage, conservation, and coupling provides the reader with a practical understanding of these five main topic areas of energy including 130 examples and over 600 practice problems."

"Concerns over dwindling fossil fuel reserves and impending climate changes have focused attention worldwide on the need to discover alternative, sustainable energy sources and fuels. Biofuels, already produced on a massive industrial scale, are seen as one answer to these problems. However, very real concerns over the effects of biofuel production on food supplies, with some of the recent increases in worldwide food costs attributable to biofuel production, have lead to the realization that new, non-food substrates for biofuel production must be bought online. This book is an authoritative, comprehensive, up-to-date review of the various options under development for the production of advanced biofuels as alternative energy carriers. "

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Masalah lingkungan seperti polusi sistem perairan telah mendorong urgensi penyusunan teknologi pengolahan limbah yang lebih baik. Nitrat adalah salah satu target pencemar yang digunakan dalam asesmen kualitas air. Saat ini, proses biologis untuk eliminasi nitrat dari sistem perairan sedang dikembangkan sebagai alternatif untuk proses-proses fisika-kimia yang sering digunakan. Microbial electrolysis cell (MEC) adalah teknologi baru yang diajukan untuk tujuan tersebut. Penelitian ini bertujuan memasangkan proses eliminasi nitrat dengan produksi biohidrogen (bio-H₂) di sistem MEC. Cakupan studi ini adalah dua sistem yang disebut mini-MEC dan MEC. Kedua sistem tersebut dibedakan berdasarkan volumenya. Parameter optimum operasi (V_ext dan sumber karbon) ditetapkan pada sistem mini-MEC sebelum beralih ke sistem MEC. Kondisi optimum ditentukan pada V_ext 0,7 V dengan asetat sebagai sumber karbon terbaik. Sistem dievaluasi berdasarkan performa luaran elektrikal (I_d, P_d), eliminasi nitrat (RE%, R_NO3-), dan produksi bio-H₂ (H_max, R_H2, dan Y_H2). Konsorsium desain (kode konsorsium: IS dan IW) disusun berdasarkan hasil penelitian sebelumnya dengan kinerja eliminasi nitrat dan lokasi isolasi sebagai kriteria desain. Konsorsium desain dibandingkan dengan konsorsium alam (S) di MEC skala 100 mL untuk proses simultan eliminasi nitrat dan produksi biohidrogen. Konsorsium IS memberikan hasil terbaik dari segi profil produksi biohidrogen dengan H_max 10,6515 mg L^-1, Y_H2 6,491 mg g^-1, dan R_max 0,0867 mg L^-1 jam^-1. Konsorsium alam S memberikan performa terendah dari ketiga konsorsium yang diuji. Data dari konsorsium IS dievaluasi terhadap model untuk pertumbuhan dan produksi biohidrogen. Model Gompertz dan logistik termodifikasi dapat mendeskripsikan data dengan baik berdasarkan parameter fit R². Estimasi parameter model dilakukan melalui metode non-linear least square. Hasil estimasi parameter model Gompertz yang telah dioptimasi adalah 0,1659 untuk R_max, 10,2495 untuk H_max, dan 30,0607 untuk l. Selanjutnya, studi ini dapat dikembangkan ke arah penyusunan model prediktif profil bio-H₂ pada sistem MEC berdasarkan hubungan linear antara profil bio-H₂ dan pertumbuhan sel.

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Environmental problems, especially pollution to water systems have urged research into cleaner wastewater treatment strategies. Nitrate is one of the main targets for water quality control. The use of biological processes to remove nitrate from water systems is being studied as alternatives to current physico-chemical practices. Microbial electrolysis cell (MEC) emerged as a new technology that is appropriate for this purpose. This research aim to pair nitrate elimination with biohydrogen production in MEC. The study worked on two scales of MECs, referred to as mini-MEC (20 mL) and MEC (100 mL). Operating parameters (V_ext and carbon source) was determined on mini-MEC using axenic cultures of known denitrifying bacteria. V_ext was set at 0.70 V and CH₃COONa was selected as carbon source for subsequent experiments. System was evaluated based on electrical outputs (I_d, P_d), nitrate elimination (RE%, R_NO3-), and biohydrogen production (H_max, R_H2, and yield). Synthetic microbial consortia were designed based on isolates obtained in a previous research using nitrate elimination and site characteristics as design criteria. Designed consortia (IS and IW) was compared against naturally occurring soil microbial consortium (S) in 100 mL MEC for simultaneous biohydrogen production and nitrate elimination. Consortium IS yield better biohydrogen production profile with H_max of 10.6515 mg L^-1, Y_H2 at 6.491 mg g^-1, and R_max 0.0867 mg L^-1 h^-1. Consortium S performed the worst out of three with declining H₂ concentration curves at later operation period. The data from consortium IS was evaluated against models for bio-H₂ production. Modified Gompertz model could describe the data well based on comparison of fit parameter R² against modified logistic model. Model optimization was carried out by non-linear least square methodology. Optimized parameter values were 0.1659 for R_max, 10.2495 for H_max, and 30.0607 for l. Future studies should explore the design of a predictive model for H₂ production based on microbial growth in MEC inoculated with microbes with similar profile to IS consortium.

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"Material lignoselulosa adalah salah satu sumber energi terbarukan yang menjanjikan untuk energi dan produk kimia Bioetanol adalah termasuk biofuel yang memiliki keunggulan lebih ramah lingkungan dan menjaga ketersediaan minyak bumi Penelitian ini melakukan studi penggunaan model prediktif Analytical Semi Empirical Model ASEM dalam merepresentasikan tahapan biokonversi dari biomass lignoselulosa menjadi produk glukosa monosakarida yakni reaksi hidrolisis kimiawi yang diproses lebih lanjut akan menjadi bioetanol Penelitian ini bertujuan menentukan kondisi suhu optimum dalam aspek ekonomis dan kualitas melalui simulasi model ASEM Data eksperimen sekunder dari bahan mentah yang mengandung material lignoselulosa disimulasikan dengan perangkat lunak komputasi numerik menggunakan metode curve fitting Hasil dari simulasi untuk suhu optimum memproduksi produk dominan glukosa monosakarida berkisar antara 433 ndash 488 K Dengan akurasi nilai R2 yang mendekati 1 berkisar antara 0 8729 ndash 0 9978 dan SSE yang mendekati 0 berkisar antara 7 577 ndash 0 5574 bergantung pada bahan mentah yang digunakan dan jenis produk dominan yang diinginkan.

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Lignocellulosic materials are among the most promising renewable feedstocks for the production of energy and chemicals. Bioethanol is a major biofuelcan be produced from lignocellulosic materials and also advantages are environmental friendly and maintain availability of petroleoum. This researchstudy implementation the predictive Analytical Semi Empirical Model(ASEM) in representingglucose/monosaccharide whicha bioconversion stage from lignocellulosic materials to bioethanol, chemical hydrolysis/acid hydrolysis. This research aims optimum temperature condition each products through simulation producing glucose in higher economical and quality aspect by ASEM model simulation. Experimental secondary data of raw materials which contain lignoselluosic are simulated using Numerical Computation Software with curve fitting method. The result of the simulation, optimum temperature condition to produce glucose/monosaccharide is 433-488 K.With accuracy R2 value is 0,8729-0,9978 and SSE value is 7,577-0,5574 depend on raw material and desirable product."

"Tandan kosong kelapa sawit (TKKS) merupakan salah satu jenis limbah lignoselulosa primer dari industri kelapa sawit. TKKS merupakan bahan baku yang menjanjikan untuk dikonversi menjadi produk bernilai tambah seperti bioetanol. Namun, pemanfaatan TKKS untuk menghasilkan bioetanol masih menjadi tantangan dalam skala industri. Oleh karena itu, penelitian ini melakukan analisis risiko tekno-ekonomi akan pabrik bioetanol dengan bahan baku TKKS. Proses produksi bioetanol terdiri dari tiga tahap: pretreatment, sakarifikasi dan fermentasi serentak (SSF), dan pemurnian. Model simulasi dilakukan dengan menggunakan perangkat lunak Aspen Plus, dan evaluasi kelayakan ekonomi menggunakan metode real option yang dilakukan dengan menggunakan perangkat lunak Microsoft Office Excel. Data untuk membuat simulasi proses produksi semi-kontinyu skala industri diperoleh dari penelitian-penelitian sebelumnya. Penelitian ini menghasilkan bioetanol dengan yield sebesar 399 L/ton untuk kapasitas produksi sebesar 6.000 kL/tahun dengan biaya produksi sebesar 0,59 USD/L. Analisis profitabilitas menghasilkan nilai NPV, IRR, PBP, dan PI berturut-turut sebesar 3.097.581 USD, 16%, 6,16 tahun, dan 3,44. Analisis risiko dengan metode real option dengan nilai volatility (σ) sebesar 9% menghasilkan keputusan yang dapat diambil yaitu: (1) Proyek berjalan pada awal tahun; (2) Pada akhir tahun ke-1 bisa mulai dilakukan ekspansi; (3) Pabrik berhenti beroperasi pada tahun ke-20 dengan memperoleh salvage value sebesar 619.516 USD.

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Oil palm empty fruit bunch (EFB) is a type of primary lignocellulosic residue from the palm oil industry. They are promising feedstocks for bioconversion into value-added products such as bioethanol. However, using empty fruit to produce bioethanol remains a challenge on an industrial scale. As a result, this study conducted a techno-economic and risk analysis of an EFB bioethanol plant. The bioethanol production process consists of three stages: pretreatment, simultaneous saccharification and fermentation (SSF), and purification. The simulation model carried out using Aspen Plus, and the economic feasibility assessed using the real option method, which carried out using Microsoft Office Excel. The data from the previous experiment was used to create a simulation of an industrial-scale semi-continuous production process. With a yield of 399 L/ton and a production capacity of 6,000 kL/year, this study produced bioethanol at a cost of 0.59 USD/L. NPV, IRR, PBP, and PI values from the profitability analysis were 3,097,581 USD, 16%, 6.16 years, and 3.44, respectively. The following decisions can be made as a result of risk analysis using the real option method with a volatility value of 42 percent: (1) The project is open at the start of the year; (2) Expansion can start at the end of the first year; and (3) The plant will be abandoned at the end of the 20th year by obtaining a salvage value of 619,516 USD."