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11.
Ashwin Gaikwad 《Chemical Engineering Communications》2018,205(1):47-81
As the biofuel industry is heavily depend on technological advancement to remain competent, creation of new process techniques becomes inevitable to replace the existing under-performed operations. Mixing in the reactor requires enormous amount of energy to achieve required homogeneity. Reduction in the energy consumption and ultimately the cost of the product is possible by devising smart mixing strategies. In this review, interactions of mixing and reaction kinetics of enzymatic hydrolysis, fermentation, and cellulosic depolymerization in ionic solvents are discussed. When the processes are operated under various mixing conditions, changes in the reaction kinetics and dynamics of the processes occur. Therefore, analyzing the mixing effects at various levels (micro to macro) is crucial to decide best operating mixing conditions that drive the reaction kinetics toward the increased product yield. The review is helpful to identify a suitable mixing strategy that maximizes the production of biofuels—ethanol, 5-hydroxymethylfurfural, etc. 相似文献
12.
At the focus of abiotic chemical reactions is the synthesis of ribose. No satisfactory explanation was provided as to the missing link between the prebiotic synthesis of ribose and prebiotic RNA (preRNA). Hydrogen cyanide (HCN) is assumed to have been the principal precursor in the prebiotic formation of aldopentoses in the formose reaction and in the synthesis of ribose. Ribose as the best fitting aldopentose became the exclusive sugar component of RNA. The elevated yield of ribose synthesis at higher temperatures and its protection from decomposition could have driven the polymerization of the ribose-phosphate backbone and the coupling of nucleobases to the backbone. RNA could have come into being without the involvement of nucleotide precursors. The first nucleoside monophosphate is likely to have appeared upon the hydrolysis of preRNA contributed by the presence of reactive 2′-OH moieties in the preRNA chain. As a result of phosphorylation, nucleoside monophosphates became nucleoside triphosphates, substrates for the selective synthesis of genRNA. 相似文献
13.
Ileana de los A. Gremasqui Maria A. Giménez Manuel O. Lobo Norma C. Sammán 《International Journal of Food Science & Technology》2021,56(12):6507-6514
The objective was to study the nutritional and functional properties of hydrolysates from quinoa (Chenopodium quinoa) obtained by enzymatic hydrolysis of defatted quinoa flour (DQF). The commercial enzymes alcalase and flavourzyme were used to obtain the hydrolysates defatted quinoa flour hydrolysate with alcalase (DQFA) and defatted quinoa flour hydrolysate with flavourzyme (DQFF), respectively, after 3 h of digestion at 50°C and pH 8. The degree of hydrolysis (47.32%), yield (31.05%) and protein recovery (88.80%) values were higher in DQFA; however, its protein content (48.34%) was lower compared to that of DQFF (55.06%). Also, DQFA had a solubility greater than 57% over a wide pH range (2–10) and good foam stability (70–90%). On the other hand, DQFF presented adequate emulsifying activity (61.30 m2/g), emulsifying stability (158.62 min) and foaming capacity (131%). Due to the high content of macro- and micronutrients and adequate emulsifying and foaming properties, DQFA and DQFF could be used as ingredients in various processed food products and protein supplements. 相似文献
14.
Sibel Duman Bülent Kaya Fatma Caf Barış Enez Sema Aguloğlu Fincan 《International Journal of Hydrogen Energy》2021,46(29):15410-15430
For the first time in this innovative study, microorganisms such as Bacillus simplex bacteria, mostly used in biological activity studies, are used as a bio-supporter agent of iron to release hydrogen from sodium borohydride hydrolysis at 25.0 ± 0.1 °C. The goal is to investigate thoroughly sodium borohydride hydrolysis catalyzed by Fe2O3 nanoparticles impregnated on microorganism such as Bacillus simplex (BS) bacteria (Fe2O3@BS NPs) known with strong antibacterial properties, which makes innovative them a candidate for hydrolysis reaction. This study was focused on the preparation, identification, and catalytic use of biocatalyst-like Fe2O3@BS NPs for hydrogen release from the sodium borohydride hydrolysis at 25.0 ± 0.1 °C. The characterization results made after and before hydrolysis reaction using by SEM/SEM-EDX, FT-IR, XRD, UV–vis, XPS, DLS, ELS Zeta potential, ESR, and TEM techniques reveal the formation of highly active, stable, durable, and long-lived biocatalysts-like Fe2O3@BS NPs. 相似文献
15.
Anne Stöbener Mario Fabuel Ortega Christoph J. Bolten Edwin Ananta Shantha Nalur Andreas Liese 《International Journal of Food Science & Technology》2020,55(3):1265-1271
Partial glycerides are widely used ingredients in confectionery products that can be produced from natural fats. In a biocatalytic partial hydrolysis of cocoa butter and palm oil fractions, a product mixture containing 1.5% monoglycerides and 5.5% diglycerides intended for the use in confectionery products was created. This study is a proof of principle that shows the feasibility of monitoring the biocatalytic partial hydrolysis of these two natural fats in situ with ATR-FTIR spectroscopy. An economic approach was utilised for calibration since partial glyceride calibration standards are costly and poorly available. The released compounds were quantified by means of chemometric modelling, and the model was validated with gas chromatography. Resulting root mean square errors were in the low per cent range. Additionally, the results indicate that distinction of the released free fatty acids is possible with ATR-FTIR spectroscopy. 相似文献
16.
Prediction of overall glucose yield in hydrolysis of pretreated sugarcane bagasse using a single artificial neural network: good insight for process development 下载免费PDF全文
17.
Jianming Guo Kaixuan Huang Shizhong Zhang Yong Xu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(3):694-701
The cover image is based on the Original Article Optimization of selective acidolysis pretreatment for the valorization of wheat straw by a combined chemical and enzymatic process by Yong Xu, Jianming Guo, Shizhong Zhang et al., https://doi.org/10.1002/jctb.6251 .
18.
Corn stover was pretreated with dilute sulfuric acid to test the interaction effects of pH, cellulase loading and β-glucosidase loadings on biomass hydrolysis rates. A response surface model was developed showing that β-glucosidase supplementation had limited practical impact on hydrolysis between 0.5 and 2 CBU FPU−1. The only significant interaction in the model was between pH and β-glucosidase loading but it also had little practical significance. Corn stover and corn cob were used to test the effects of further β-glucosidase reduction. Significant hydrolysis improvements were seen when 0.2 CBU FPU−1 were added but very little improvement was seen for higher loadings. Residual cellobiose concentrations confirmed these findings but suggest that further reductions would have more noticeable negative effects on hydrolysis rates. Results show that β-glucosidase supplementation during biomass hydrolysis can be reduced to between 10% and 20% of typical loadings. 相似文献
19.
20.
Functional expression and synergistic cooperation of xylan‐degrading enzymes from Hypocrea orientalis and Aspergillus niger 下载免费PDF全文