scholarly journals Production, Purification, and Identification of Cholest-4-en-3-one Produced by Cholesterol Oxidase from Rhodococcus sp. in Aqueous/Organic Biphasic System

2015 ◽  
Vol 8s1 ◽  
pp. BCI.S21580 ◽  
Author(s):  
Ke Wu ◽  
Wei Li ◽  
Jianrui Song ◽  
Tao Li
Keyword(s):  
Cholesterol Oxidase ◽  
Enzymatic Reaction ◽  
Reaction System ◽  
Phase System ◽  
Separation And Purification ◽  
Two Phase ◽  
Whole Cells ◽  
Steroid Drugs ◽  
Set Up ◽  
The Cost

Cholest-4-en-3-one has positive uses against obesity, liver disease, and keratinization. It can be applied in the synthesis of steroid drugs as well. Most related studies are focused on preparation of cholest-4-en-3-one by using whole cells as catalysts, but production of high-quality cholest-4-en-3-one directly from cholesterol oxidase (COD) using an aqueous/organic two-phase system has been rarely explored. This study set up an enzymatic reaction system to produce cholest-4-en-3-one. We developed and optimized the enzymatic reaction system using COD from COX5-6 (a strain of Rhodococcus) instead of whole-cell biocatalyst. This not only simplifies and accelerates the production but also benefits the subsequent separation and purification process. Through extraction, washing, evaporation, column chromatography, and recrystallization, we got cholest-4-en-3-one with purity of 99.78%, which was identified by nuclear magnetic resonance, mass spectroscopy, and infrared spectroscopy. In addition, this optimized process of cholest-4-en-3-one production and purification can be easily scaled up for industrial production, which can largely decrease the cost and guarantee the purity of the product.

A two-phase system for the clean and high yield synthesis of furylmethane derivatives over –SO3H functionalized ionic liquids

2017 ◽  
Vol 19 (20) ◽  
pp. 4804-4810 ◽  
Author(s):  
S. H. Shinde ◽  
C. V. Rode
Keyword(s):  
Ionic Liquids ◽  
Reaction System ◽  
High Yield ◽  
Phase System ◽  
Phase Reaction ◽  
Two Phase ◽  
Yield Production ◽  
High Yield Production

A new and effective unique two-phase reaction system for the high yield production of tri(furyl)methane from furfural and furan.

Influence of Compressed Carbon Dioxide on the Oxidation of Cyclohexane with Hydrogen Peroxide in Acetic Acid

2006 ◽  
Vol 59 (3) ◽  
pp. 225 ◽  
Author(s):  
Liang Gao ◽  
Tao Jiang ◽  
Buxing Han ◽  
Baoning Zong ◽  
Xiaoxin Zhang ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Peroxide ◽  
Acetic Acid ◽  
Binary System ◽  
Reaction System ◽  
Phase Region ◽  
Phase Behaviour ◽  
Phase System ◽  
Two Phase ◽  
Three Phase

The oxidation of cyclohexane with H2O2 in a compressed CO2/acetic acid binary system was studied at 60.0 and 80.0°C, at pressures up to 18 MPa, and with the zeolite TS-1 as catalyst. The phase behaviour of the reaction system was also observed. There are three fluid phases in the reaction system at lower pressure but two at higher pressures. In the three-phase region the yields of the products, cyclohexanol and cyclohexanone, increase considerably with increasing pressure and reaches a maximum near the phase-separating pressure. CO2 can thus enhance the reaction effectively. However, the effect of pressure on the yield is very limited after the transition to a two-phase system.

Biogas production from cheese whey wastewater: laboratory- and full-scale studies

2014 ◽  
Vol 69 (6) ◽  
pp. 1320-1325 ◽  
Author(s):  
K. Stamatelatou ◽  
N. Giantsiou ◽  
V. Diamantis ◽  
C. Alexandridis ◽  
A. Alexandridis ◽  
...  
Keyword(s):  
High Efficiency ◽  
Cheese Whey ◽  
Biogas Production ◽  
Oxygen Demand ◽  
Full Scale ◽  
Laboratory Scale ◽  
Phase System ◽  
Two Phase ◽  
Set Up ◽  
Cheese Production

A two-phase system for biogas production from cheese whey wastewater (CWW) was designed, set up and operated at laboratory and full scale for a whole cheese production season (8–9 months). The high efficiency and stability of the laboratory-scale system was demonstrated under various organic loading rates (OLRs) reaching 13 g chemical oxygen demand (COD) L−1d−1 and producing up to 9 L L−1d−1 of biogas (approximately 55% in methane). The COD removal was above 95% and the pH was maintained above 6.3 without any chemical addition. The full-scale system was operated at lower OLRs than its normal capacity, following the good response and high stability in disturbances of the laboratory-scale unit.

scholarly journals Surveillance of Resistance to New Antibiotics in an Era of Limited Treatment Options

2021 ◽  
Vol 8 ◽  
Author(s):  
Chantal M. Morel ◽  
Marlieke E. A. de Kraker ◽  
Stephan Harbarth ◽  
Keyword(s):  
Antimicrobial Resistance ◽  
Treatment Options ◽  
National Level ◽  
Essential Elements ◽  
Phase System ◽  
Surveillance Systems ◽  
Two Phase ◽  
Modified Delphi ◽  
New Antibiotics ◽  
Set Up

As with any health threat, our ability to respond to the emergence and spread of antimicrobial resistance depends on our ability to understand the scale of the problem, magnitude, geographical spread, and trends over time. This is especially true for resistance emergence to newer antibiotics coming to the market as last-resort treatments. Yet current antibiotic surveillance systems are limited to monitoring resistance to commonly prescribed drugs that have been on the market for a long time. This qualitative study determined the essential elements and requirements of antimicrobial resistance surveillance for new antibiotics based on literature review, interviews and expert consensus. After an extensive mapping exercise, 10 experts participated in a modified Delphi consultation to identify consensus on all elements required for surveillance of resistance to novel antibiotics. The main findings indicate that there is a need for a two-phase system; an early alert system transitioning to routine surveillance, led by the public sector to gather and share essential data on resistance to newer antibiotics in a transparent manner. The system should be decentralized, run largely from national level, but be coordinated by an arm of an existing international public health institution. Priority should be given to monitoring emergence of resistance among already multi-drug resistant pathogens causing infections, over a broader selection of pathogens to maximize clinical impact. In conclusion, we cannot rely on current AMR surveillance systems to monitor resistance emergence to new antibiotics. A new, public system should be set-up, starting with a focus on detecting resistance emergence, but expanding to a more comprehensive surveillance as soon as there is regional spread of resistance to the new antibiotic. This article provides a framework based on expert agreement, which could guide future initiatives.

scholarly journals Production strategy influence on the economic viability of a family fish farm in Pará state, Amazon, Brazil

2021 ◽  
Vol 9 (1) ◽  
pp. 540-549
Author(s):  
Marcos Ferreira Brabo ◽  
Gerfeson Almeida da Silva ◽  
Daniel Abreu Vasconcelos Campelo ◽  
Galileu Crovatto Veras ◽  
Andréia Santana Bezerra ◽  
...  
Keyword(s):  
Single Phase ◽  
Net Present Value ◽  
Cost Benefit ◽  
Phase System ◽  
Operational Cost ◽  
Internal Rate Of Return ◽  
Two Phase ◽  
Cost Benefit Ratio ◽  
The Cost ◽  
Capital Return

The objective of this study was to analyze the influence of the adoption of single-phase and two-phase system on the economic feasibility of tambaqui (Colossoma macropomum) family production in the Tracuateua municipality, Pará state. The operational cost methodology and economic efficiency indicators were adopted to compare these rearing systems. The annual production was 4,200 kg and 5,826 kg. The operational costs were R$ 26,169.00 and R$ 34,365.00, the total operational cost was R$ 27,505 and R$ 35,701.00, and the total operational cost per kg was R$ 6.55 and R$ 6.13 for single-phase and two-phase systems, respectively. Regarding the indicators, the net present value was R$ 24,180.70, the internal rate of return was 24%, the cost-benefit ratio was 1.19, and the capital return period was four years in the single-phase system. In the two-phase period, the net present value was R$ 48,582.06, the internal rate of return was 29%, the cost-benefit ratio was 1.25, and the capital return period was 3.6 years. Despite the demand for greater investment, the two-phase system proved to be more profitable than the single-phase system, promoting even a reduction in unit production cost.

FEATURES OF MECHANISM OF GAS-LIQUID POLYAMIDATION IN FOAMY HYDRODYNAMIC MODE

2020 ◽  
Vol 63 (3) ◽  
pp. 67-74
Author(s):  
Vladimir A. Nikiforov ◽  
Elena I. Laguseva ◽  
Evgeny A. Pankratov ◽  
Ilya S. Zhokhov
Keyword(s):  
Liquid Phase ◽  
Dicarboxylic Acid ◽  
Gas Phase ◽  
Reaction System ◽  
Reaction Chamber ◽  
Phase System ◽  
Aromatic Diamines ◽  
Two Phase ◽  
Reactor Unit ◽  
Hydrodynamic Mode

The brief characteristics of the reaction system of pilot production of fatty-aromatic polyamides based on aliphatic diamines (acylated monomers) and dicarboxylic acid dichloroanhydrides (acylating monomers) by the method of gas-liquid polycondensation in a highly turbulized foamy hydrodynamic mode are described. Technological scheme and rational instrumentation of the technology of polyterephthalamides, the reactor unit (reactor-fibridator), which includes a two-stage reaction chamber and a gas phase generating chamber coaxially located under it, chemistry and operating principle of the facility are shown. The method combines the chemical processes of polyamidation with the physical processes of the reaction molding of polyamide fibrids or gas-structural elements used in the technology of gas-filled plastics. The reaction system of the method includes three structural units: a liquid phase (aqueous alkaline solution of aliphatic, cycloaliphatic and fatty-aromatic diamines), a gas phase (superheated vapours of aromatic and aliphatic dicarboxylic acid dichloroanhydrides, dispersed in a dynamic airflow or inert gas) and an interface (gas-liquid interface). Gas-liquid polyamidation is accompanied by phase formation: the reaction system during the process becomes three-phase system – the swollen polymer forms a solid mobile phase (target product), which acts as a foamy mode stabilizer, which allows technological process to proceed at optimal linear gas phase rates of 30–35 m/s (unlike classical two-phase foamy mode – 4 m/s). A polyamidation mechanism at the liquid-gas interface is proposed, which includes two versions of the process (adsorption and condensation) depending on the ratio of the temperature characteristics of the acylated monomer and the liquid phase carrying the acylating monomer. Analysis of the proposed versions of the mechanism allows you to make an engineering decision on the expediency of organizing a cycle in the liquid phase. Possible criteria for predicting the versions of the mechanism and examples of reaction systems with condensation and absorption versions of polyamidation are given.

Study on Separation and Purification of Resveratrol in Wine Grape Residue with Aqueous Two Phase Extraction Method

2012 ◽  
Vol 550-553 ◽  
pp. 1743-1746 ◽  
Author(s):  
Ying Zi He ◽  
Biao Wang ◽  
Yan Zhuang ◽  
Yu Ping Lu
Keyword(s):  
Extraction Method ◽  
Hplc Analysis ◽  
Phase System ◽  
Phase Extraction ◽  
Wine Grape ◽  
Separation And Purification ◽  
Two Phase ◽  
Organic Solvent Extraction ◽  
Primary Separation ◽  
Aqueous Two Phase Extraction

The separation and purification of resveratrol in wine grape residue with aqueous two phase extraction method were studied in this paper. Used identified ethanol - ammonium sulfate - water as the aqueous two-phase system, the wine grape residue extract substances separated well. By TLC and HPLC analysis, resveratrol content (13.3μg/ml) in aqueous two-phase extraction was higher than the results (2.342μg/ml) in organic solvent extraction. The results showed that the aqueous two phase extraction method could be used in primary separation and purification of resveratrol in wine grape residue.

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