scholarly journals Study on optimum technological conditions for producing androstenedione by microbial method

2019 ◽  
Vol 136 ◽  
pp. 06025
Author(s):  
Haishan SHI ◽  
Ying YANG ◽  
Weihua LI ◽  
Hui ZHANG ◽  
Xiaolei CHENG
Keyword(s):  
Substrate Concentration ◽  
Large Scale ◽  
Supply And Demand ◽  
Process Conditions ◽  
Phase System ◽  
Scale Production ◽  
Liquid Loading ◽  
Two Phase ◽  
Initial Ph ◽  
Promising Development

As an indispensable intermediate, androstenedione is widely used in drug manufacturing, especially steroidal drugs. However, the chemical manufacturing process of androstenedione is generally complicated and difficult, and it will cause serious environmental pollution in the production process. The biological method for the production of androstenedione has a very promising development prospect, because it is more economical and environmentally friendly than chemical methods. In order to better produce androstenedione on a large scale, the imbalance between supply and demand can be solved. In this study, the biaqueous phase system was used to increase the substrate concentration, and the method of transforming plant sterol by mycobacterium was used to produce androstenedione. The optimal conditions for the production of androstenedione by microbial assay were determined by orthogonal test: the aqueous two-phase system was water/ sunflower oil, the temperature was 30 °C, the initial pH was 6.5, the substrate concentration was 0.4 g/L, the rotation speed was 250 rpm, and the inoculation was carried out. The amount was 14.83%, the organic ratio was 20.65%, and the liquid loading was 150/500 mL. The preliminary production of androstenedione by microbial method has found suitable process conditions and provided data and theoretical support for its large-scale production.

Effect of Slag on Mixing Time in Gas-Stirred Ladles Assisted with a Physical Model

2012 ◽  
Vol 1485 ◽  
pp. 101-106 ◽  
Author(s):  
Adrián M. Amaro-Villeda ◽  
A. Conejo ◽  
Marco A. Ramírez-Argáez
Keyword(s):  
Physical Model ◽  
Mixing Time ◽  
Steel Slag ◽  
Slag Layer ◽  
Process Conditions ◽  
Steel Ladle ◽  
Phase System ◽  
Mixing Times ◽  
Two Phase ◽  
Energy Dissipated

ABSTRACTA 1/6th water physical model of a 140 tons gas-stirred steel ladle is used to evaluate mixing times (τm at 95% of chemical uniformity) in a two phase system without slag (air-water) and in a more realistic three phase system (air-water-oil) to simulate the argon-steel-slag system and quantify the effect of the slag layer on the mixing time. Slag layer is kept constant at 0.004 m. Mixing times are estimated through measured changes in pH due to the addition of a tracer (NaOH 1 M). The effect of the following variables on the mixing time is evaluated for a single injector: gas flow rate (7, 17 y 37 l/min) and the injector position (R/r= 0, 1/3, ½, 2/3 and 4/5). Experimental results obtained in this work show good agreement when compared against mixing time correlations reported by Mazumdar for the two phase air-water case (no slag considered). Another comparison is done using the new concept called “effective bath height” proposed by Barati, where the mixing time is a function of the size of the slag layer since this layer dissipates part of the total amount of stirring energy introduced into the ladle by the injection of gas. Agreement is not good in this case. Finally, an estimation of the percentage of the stirring energy dissipated by the slag is computed, including other factors that govern the dissipation of stirring energy. Percentage of energy dissipated by the slag is found to be between 2.7 to 12 % depending on the process conditions.

Study on the Role of Surfactants to Aqueous Two-Phase Synthesizing CPAM

2013 ◽  
Vol 781-784 ◽  
pp. 511-514
Author(s):  
Ya Feng Cao ◽  
Mei Jun Qu ◽  
Feng Zhi Tan ◽  
Zhao Li Liu ◽  
Yuan Li
Keyword(s):  
Monomer Conversion ◽  
Continuous Phase ◽  
Ionic Surfactants ◽  
Process Conditions ◽  
Phase System ◽  
Two Phase ◽  
Optimum Reaction ◽  
Optimum Reaction Condition ◽  
Better Than

In this paper,cationic polyacrylamide (CPAM) was synthesized by using aqueous two-phase polymerization. The Role of surfactants to aqueous two-phase synthesizing CPAM was studied, including the effect of the type,the composition and the concentration of the surfactants. The results showed that non-ionic surfactants had a better stabilizing impact on the polymer aqueous two-phase system. And the effect of the compound surfactant was better than that of a single surfactant. Take the chemical compound of Tween80 and OP10 as the polymerization auxiliaries, the optimum reaction condition of synthesis were as follows:wTween80:ѡOP10=1.5,w=1.6%, 50°C.In this process conditions, the distribution coefficient was the most appropriate in the continuous phase, the total monomer conversion rate and the intrinsic viscosity number of the product reached the maximum.

Large-scale room-temperature synthesis and optical properties of perovskite-related Cs4PbBr6 fluorophores

2016 ◽  
Vol 4 (45) ◽  
pp. 10646-10653 ◽  
Author(s):  
Daqin Chen ◽  
Zhongyi Wan ◽  
Xiao Chen ◽  
Yongjun Yuan ◽  
Jiasong Zhong
Keyword(s):  
Optical Properties ◽  
Large Scale ◽  
Room Temperature ◽  
Interface Reaction ◽  
Phase System ◽  
Temperature Synthesis ◽  
Two Phase ◽  
Room Temperature Synthesis

An inhomogeneous interface reaction in a liquid–liquid immiscible two-phase system is developed to realize the large-scale room-temperature synthesis of perovskite-related Cs4PbBr6 fluorophores.

scholarly journals A two-phase bromination process using tetraalkylammonium hydroxide for the practical synthesis of α-bromolactones from lactones

2021 ◽  
Vol 17 ◽  
pp. 2906-2914
Author(s):  
Yuki Yamamoto ◽  
Akihiro Tabuchi ◽  
Kazumi Hosono ◽  
Takanori Ochi ◽  
Kento Yamazaki ◽  
...  
Keyword(s):  
Large Scale ◽  
Phase System ◽  
Methyl Ethyl ◽  
Two Phase ◽  
One Pot ◽  
Mild Conditions ◽  
Substoichiometric Amount ◽  
Practical Synthesis ◽  
Industrial Use

A simple and efficient method for α-brominating lactones that affords α-bromolactones under mild conditions using tetraalkylammonium hydroxide (R4N+OH−) as a base was developed. Lactones are ring-opened with Br2 and a substoichiometric amount of PBr3, leading to good yields of the corresponding α-bromocarboxylic acids. Subsequent intramolecular cyclization over 1 h using a two-phase system (H2O/CHCl3) containing R4N+OH− afforded α-bromo lactones in good yields. This method can be applied at the 10 mmol scale using simple operations. α-Bromo-δ-valerolactone, which is extremely reactive and difficult to isolate, could be isolated and stored in a freezer for about one week using the developed method. Optimizing the solvent for environmentally friendly large-scale syntheses revealed that methyl ethyl ketone (MEK) was as effective. In addition, in situ-generated α-bromo-δ-valerolactone was directly converted into a sulfur-substituted functional lactone without difficulty by reacting it with a sulfur nucleophile in one pot without isolation. This new bromination system is expected to facilitate the industrial use of α-bromolactones as important intermediates.

Aqueous Two-Phase System in the Synthesis of Starch Graft Acrylamide Polymer

2014 ◽  
Vol 672-674 ◽  
pp. 734-736 ◽  
Author(s):  
Meng Zheng ◽  
Ling Xun Liang
Keyword(s):  
Base Material ◽  
Monomer Concentration ◽  
Monomer Conversion ◽  
Raw Material ◽  
Polymerization Reaction ◽  
Optimum Process ◽  
Process Conditions ◽  
Phase System ◽  
Two Phase ◽  
Aqueous Two Phase System

With starch as base material, acrylamide (AM) as raw material, polyethylene glycol (PEG20000) as dispersing medium, in aqueous two-phase system synthesized starch grafting acrylamide polymer. Through the indoor experiment, determine the optimum process conditions of polymerization reaction, the initial monomer concentration was 15%, PEG20000 concentration of 10%, m (ST) : m (AM) = 3:7, dosage of initiator is 0.1%, T = 50 °C, T = 6 h. Get monomer conversion was 98.5%, the characteristic viscosity.methods according to 761.5 mg/L of graft copolymerization. Of product have been characterized through infrared spectrum and analysis.

A Process for large-scale isolation of ?-galactosidase fromE. coli in an aqueous two-phase system

1983 ◽  
Vol 25 (7) ◽  
pp. 1789-1800 ◽  
Author(s):  
Andres Veide ◽  
Anna-Lisa Smeds ◽  
Sven-Olof Enfors
Keyword(s):  
Large Scale ◽  
Phase System ◽  
Two Phase ◽  
Aqueous Two Phase System

scholarly journals Process Evaluation of Recombinant Chitin Deacetylase Expression in E. Coli Rosetta pLysS Cells using Statistical Design of Experiments

2021 ◽  
Author(s):  
Goutam Mohan Pawaskar ◽  
Ritu Raval ◽  
Subbalaxmi S
Keyword(s):  
Large Scale ◽  
Statistical Design ◽  
Fold Increase ◽  
Process Conditions ◽  
Scale Production ◽  
Statistical Design Of Experiments ◽  
Chitin Deacetylase ◽  
E Coli ◽  
Nutritional Conditions ◽  
Wide Range

Abstract Chitin is a natural polymer with N-acetylglucosamine units, extracted from seafood waste as a major source. It remains an underexplored polymer due to its crystalline structure. The commercial applicability can be improved if we could make it soluble. One of the routes employed to decrease this crystallinity is the conversion of chitin to chitosan via deacetylation. The industrial production of chitosan uses chemical methods, which leaves the process footprint on the environment. The greener alternative approach to producing chitosan is using chitin deacetylases (CDA). The enzymatically converted chitosan with known characteristics has a wide range of applications, importantly in the biomedical field. In the present paper, we report heterologous expression of CDA from a marine moneran; Bacillus aryabhattai B8W22. The process and the nutritional conditions were optimized for the submerged fermentation condition of E. coli Rosetta pLysS expressing the recombinant CDA using the design of experiment tools. The employment of central composite design (CCD) resulted in a ~2.39 fold increase in the total activity of expressed CDA with the process conditions of induction temperature at 22 ºC, agitation at 120 rpm, and 30 h of fermentation. The nutritional conditions required for the optimized expression were 0.061% glucose concentration and 1% lactose in media. The employment of these optimal growth conditions could result in cost-effective large-scale production of the lesser-explored moneran deacetylase, embarking on the greener route to produce biomedical grade chitosan.

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