scholarly journals Batch and continuous extraction of bromelain enzyme by reversed micelles

2009 ◽  
Vol 52 (5) ◽  
pp. 1225-1234 ◽  
Author(s):  
Ana Maria Frattini Fileti ◽  
Gilvan Anderson Fischer ◽  
José Carlos Curvelo Santana ◽  
Elias Basile Tambourgi
Keyword(s):  
Flow Rate ◽  
Batch Process ◽  
Reversed Micelles ◽  
Ananas Comosus ◽  
Time Interval ◽  
Light Phase ◽  
Continuous Extraction ◽  
Optimal Point ◽  
Pineapple Juice ◽  
Purification Factor

The main aim of this study was to optimize the conditions for bromelain extraction by reversed micelles from pineapple juice (Ananas comosus). The purification was carried out in batch extraction and a micro-column with pulsed caps for continuous extraction. The cationic micellar solution was made of BDBAC as a surfactant, isooctane as a solvent and hexanol as a co-solvent. For the batch process, a purification factor of 3 times at the best values of surfactant agent, co-solvent and salt concentrations, pH of the back and forward extractions were, 100 mM, 10% v/v, 1 M, 3.5 and 8, respectively. For the continuous operation, independent variables optimal point was determined: ratio between light phase flow rate and total flow rate equal to 0.67 and 1 second for the time interval between the pulses. This optimal point led to a productivity of 1.29 mL/min and a purification factor of 4.96.

scholarly journals Neural modeling of bromelain extraction by reversed micelles

2010 ◽  
Vol 53 (2) ◽  
pp. 455-463 ◽  
Author(s):  
Ana Maria Frattini Fileti ◽  
Gilvan Anderson Fischer ◽  
Elias Basile Tambourgi
Keyword(s):  
Flow Rate ◽  
Total Protein ◽  
Neural Model ◽  
Reversed Micelles ◽  
Operating Conditions ◽  
Protein Yield ◽  
Time Interval ◽  
Pineapple Juice ◽  
Purification Factor ◽  
Central Composite

A pulsed-cap microcolumn was used for bromelain extraction from pineapple juice by reversed micelles. The cationic micellar solution used BDBAC as the surfactant, isooctane as the solvent and hexanol as the co-solvent. In order to capture the dynamic behavior and the nonlinearities of the column, the operating conditions were modified in accordance with the central composite design for the experiment, using the ratio between the light phase flow rate and the total flow rate, and the time interval between pulses. The effects on the purification factor and on total protein yield were modeled via neural networks. The best topology was defined as 16-9-2, and the input layer was a moving window of the independent variables. The neural model successfully predicted both the purification factor and the total protein yield from historical data. At the optimal operating point, a purification factor of 4.96 and a productivity of 1.29 mL/min were obtained.

Production of Rhamnolipid Biosurfactant from Fed Batch Culture by Pseudomonas aeruginosa using Multiple Substrates

2020 ◽  
Vol 16 (6) ◽  
pp. 928-933
Author(s):  
Jujjavarapu S. Eswari
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Batch Process ◽  
Time Interval ◽  
Fed Batch ◽  
Multiple Substrates ◽  
Surface Active Agents ◽  
Limiting Nutrients ◽  
Limiting Nutrient ◽  
Surface Active ◽  
Rhamnolipid Biosurfactant

Objective: Biosurfactants are the surface active agents which are used for the reduction of surface and interfacial tensions of liquids. Rhamnolipids are the surfactants produced by Pseudomonas aeruginosa. It requires minimum nutrition for its growth as it can also grow in distilled water. The rhamnolipids produced by Pseudomonas aeruginosa are extra-cellular glycolipids consisting of L-rhamnose and 3-hydroxyalkanoic acid. Methods: The fed-batch method for the rhamnolipid production is considered in this study to know the influence of the carbon, nitrogen, phosphorous substrates as growth-limiting nutrients. Pulse feeding is employed for limiting nutrient addition at particular time interval to obtain maximum rhamnolipid formation from Pseudomonas aeruginosa compared with the batch process. Results: Out of 3 fed batch strategies constant glucose fed batch strategy shows best and gave maximum rhamnolipid concentration of 0.134 g/l.

The Effect of Boundary Layer Separation on Accuracy of Flow Measurement Using the Gibson Method

2007 ◽  
Author(s):  
F. Z. Sierra ◽  
A. Adamkowski ◽  
G. Urquiza ◽  
J. Kubiak ◽  
H. Lara ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Cross Section ◽  
Flow Rate ◽  
Pressure Difference ◽  
Proper Time ◽  
Effective Cross Section ◽  
Boundary Layer Separation ◽  
Water Hammer ◽  
Time Interval ◽  
Geometry Factor

The Gibson method utilizes the effect of water hammer phenomenon (hydraulic transients) in a pipeline for flow rate determination. The method consists in measuring a static pressure difference, which occurs between two cross-sections of the pipeline as a result of a temporal change of momentum from t0 to t1. This condition is induced when the water flow in the pipeline is stopped suddenly using a cut-off device. The flow rate is determined by integrating, within a proper time interval, the measured pressure difference change caused by the water hammer (inertia effect). However, several observations demonstrate that changes of pipeline geometry like diameter change, bifurcations, or direction shift by elbows may produce an effect on the computation of the flow rate. The paper focuses on this effect. Computational simulations have shown that the boundary layer separates when the flow faces sudden changes like these mentioned to above. The separation may reduce the effective cross section area of flow modifying a geometry factor involved into the computation of the flow rate. The remainder is directed to quantify the magnitude of such a factor under the influence of pipeline geometry changes. Results of numerical computations are discussed on the basis of how cross section reductions impact on the geometry factor magnitude and consequently on the mass flow rate.

scholarly journals Formulation and Sensory Analysis of Cocktails Based on Ginger Oleoresin (Zingiber officinale Roscoe), Pineapple Juice (Ananas comosus L. MERR) and Bissap Concentrate (Hibiscus sabdariffa)

2021 ◽  
pp. 36-47
Author(s):  
Adama Coulibaly ◽  
Pierre Ezoua ◽  
Ysidor N’guessan Konan ◽  
Souleymane Doukoure ◽  
Daouda Sidibe ◽  
...  
Keyword(s):  
Descriptive Analysis ◽  
Principal Component ◽  
Zingiber Officinale ◽  
Agricultural Products ◽  
Ananas Comosus ◽  
Hibiscus Sabdariffa ◽  
Pineapple Juice ◽  
Natural Substances ◽  
Zingiber Officinale Roscoe ◽  
Central Plan

Aims: The aim of this study is to formulate cocktails based on ginger oleoresin, pineapple juice and bissap concentrate in order to contribute to the development of these agricultural products and improve the income of producers. Study Design: The biological material consists of pineapple juice, ginger oleoresin and bissap concentrate. The oleoresin and the bissap concentrate were supplied respectively by Gazignaire (France) and the Water Chemistry and Natural Substances Laboratory. Place and Duration of Study: The cocktails were formulated and then subjected to sensory analyzes, from July to October 2018, at the Biochemistry and Food Sciences laboratory at Félix Houphouët-Boigny University. Methodology: The cocktails were formulated through a composite central plan having as variables the proportions of the pineapple juice, the bissap concentrate and the ethanol composing the cocktail. Thus 15 cocktail formulations were developed, the sensory characteristics of which were estimated. Results: Hedonic analysis of the formulations indicates acceptance of 12 of them by more than 50% of tasters.In addition, 5 formulations F4; F6; F12; F13 and F15 are preferred in proportions varying between 62% and 77%.The descriptive analysis of these 5 formulations indicates that only the pineapple flavor makes it possible to distinguish them and the F13 formulation is less provided with them.However, these formulations according to their flavor, aroma and texture are classified into 3 groups according to a principal component analysis.Which could offer consumers more choice. Conclusion: Commercial production of these cocktails could improve the availability of ginger, bissap and pineapple year-round and help improve the income of producers.

The Theory and the Practical Validation of the Fluid Level Position in the Annulus During Lost Circulation

2021 ◽  
Author(s):  
Alexey Ruzhnikov ◽  
Edgar Echevarria
Keyword(s):  
Flow Rate ◽  
Drilling Fluid ◽  
Time Interval ◽  
Fluid Level ◽  
Drilling Tool ◽  
Lost Circulation ◽  
Hole Pressure ◽  
Bottom Hole Pressure ◽  
Bottom Hole ◽  
Carbonate Formations

Abstract Carbonate formations around the world and specifically in a Middle East are prone to have total losses while drilling. And the nature of the losses often related to the highly fractured formations of the pay zone. When such fracture(s) is crossed by the wellbore the lost circulation initiated and led to a drilling without a return to a surface. To avoid undesired well control event or wellbore instability and to maintain the constant bottom hole pressure the mud cap drilling strategy often used as a preventative measure. The mud cap can be either the continuous or based on some volume or time interval, depends on the local practices or the policy of an operator. The mud cap flow rate as well as mud cap mud weight are often based on the best practices, not supported by an engineering study. To understand the behavior of the drilling fluid level in the annulus while drilling with total losses the drilling bottom hole assembly equipped with annular pressure while drilling tool was used. As the drilling required to use the continuous mud cap, then the specific guideline was developed on measurement of the bottom hole pressure and further conversion of it to the fluid level. The study was performed across pay zone with one or several loss circulation zones identified. As the result it was confirmed that the used mud cap flow rate had minor to none effect on the fluid level position in the annulus and that the bottom hole pressure remained the same. It showed as well that different loss zones are behaving in a different way, what can be considered as a factor affecting their ability to be sealed. The obtained knowledge and the information should help to understand better the loss circulation behavior as well be an important step toward development of the product which may cure the losses in high fractured carbonate formations. The results of the study can be implemented in any other project or a field.

Dehumidification and Simultaneous Removal of Selected Pollutants from Indoor Air by a Desiccant Wheel Using a 1M Type Desiccant

1999 ◽  
Vol 121 (1) ◽  
pp. 1-13 ◽  
Author(s):  
M. Popescu ◽  
T. K. Ghosh
Keyword(s):  
Silica Gel ◽  
Flow Rate ◽  
Molecular Sieve ◽  
Fixed Bed ◽  
Aluminum Foil ◽  
Time Interval ◽  
Simultaneous Removal ◽  
Desiccant Wheel ◽  
Face Velocity ◽  
Adsorption Cycle

Solid-desiccant dehumidifiers are increasingly becoming an integral part of desiccant based air-conditioning systems because of their effective handling of latent heat loads compared to conventional vapor compression units. In these units, either a silica gel or a molecular sieve is used for dehumidification of air. Both of them have the capability to co-adsorb various chemical pollutants during dehumidification of air. However, the shape of the isotherm for water vapor on these materials is not favorable for desiccant cooling applications. A mixture (IM desiccant) containing a silica gel, a molecular sieve, and a hydrophobic molecular sieve that was coated on an aluminum foil was studied for its capability for simultaneous removal of moisture and some selected pollutants from air. Experimental data were obtained in a fixed bed adsorber that simulated the operation of a rotary desiccant wheel. Air to be dehumidified and cleaned and the hot regeneration air were cycled in a specific time interval through this bed. The shape of the water isotherm on IM desiccant was found to be in between that of silica gel and molecular sieve 13×, but its uptake capacity was significantly lower than that of either silica gel or molecular sieve. A flow rate of about 100 L/min that provided a face velocity of about 132 cm/s was used in the adsorption step. The flow rate during regeneration was about 50 L/min. The temperature of the inlet air was about 23°C and its relative humidity was varied between 20 percent and 80 percent. The concentrations of pollutants were as follows; carbon dioxide: 1050 and 2300 ppm; toluene: 32 ppm; 1,1,1-trichloroethane: 172 ppm, and formaldehyde: 0.35 ppm. A complete breakthrough of all the pollutants was observed during an adsorption cycle. However, a removal efficiency greater than 50 percent for these pollutants was observed if the adsorption cycle time was about 1 minute.

Effects of gas adsorbed on solid surface during gas breakdown in electron cyclotron resonance discharge

2021 ◽  
Author(s):  
Sheng Hui Fu ◽  
Zhen- Feng Ding
Keyword(s):  
Flow Rate ◽  
Gas Flow ◽  
Electron Cyclotron Resonance ◽  
Vertical Component ◽  
Plasma Source ◽  
Time Interval ◽  
Short Time Interval ◽  
Gas Flow Rate ◽  
Ecr Plasma ◽  
Long Time

Abstract The microwave breakdown power (Pwb) in an ECR plasma source was not merely determined by pressure (gas flow rate), but found to vary with the time interval between two successive breakdowns. The measured Pwb dropped rapidly from a high value at a short time interval to a low level at a long time interval. The obtained dependence of Pwb on pressure (gas flow rate) exhibited distinct features: the normal monotonicity and abnormal non-monotonicity at the short and long time intervals, respectively. The effective zone in the antenna’s surface bombarded by hot electrons heated in the ECR layer was validated by (1) masking the antenna with a film having a variable radius; (2) calculating the distribution of the vertical component of the microwave electric field with respect to the static magnetic field; (3) imaging glows of transient breakdown discharges with a fast camera. The reduction in Pwb was mainly attributed to the enhanced emission of δ-electrons from the gas-adsorbed antenna under the bombardment of energetic electrons coming from the ECR layer.. The correlation between the dynamic gas coverage and the coefficient emission of δ-electrons was established to understand the abnormal ECR breakdown features.

Optimization of the process of reproducing units of mass and volume of liquid in a stream, mass and volumetric flow rates of liquid for calibration units with weighing devices

2020 ◽  
pp. 60-64
Author(s):  
R. A. Korneev ◽  
A. R. Tukhvatullin ◽  
V. A. Fafurin ◽  
R. R. Nigmatullin ◽  
A. V. Shchelchkov
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Storage Tank ◽  
Experimental Studies ◽  
Working Fluid ◽  
Time Interval ◽  
Flow Rates ◽  
Wide Range ◽  
Flow Switch

The publication presents an experimental method for estimating the minimum time interval for filling a storage tank with a working fluid with a fixed geometry of the nozzle of the flow switch of the calibration plant when playing units of mass and volume of fluid in the flow, mass and volumetric flow rates of the fluid. Experimental studies were performed in a wide range of mass flow rate 11,10–83,26 kg/s (40–300 t/h) with repeated static weighing of the working fluid. The flow switch is made with a fixed geometry of the flow part of the nozzle exit, which is typical for a large number of calibration units in use in our country with weighing devices. The graphical dependences of the mass flow rate on the time of filling the storage capacity obtained from the research results are the basis for optimizing the process of reproducing units of mass and volume of liquid in the flow, mass and volumetric flow rates of the liquid for calibration plants with weighing devices. These graphical dependencies made it possible to formulate recommendations on the reasonable choice of the minimum interval for filling the storage tank with working fluid in the studied range of mass flow rate. Optimization has been tested and can be extended to calibration units with weighing devices from various manufacturers with individual design and operating parameters.

scholarly journals Concentration by membrane separation processes of a medicinal product obtained from pineapple pulp

2009 ◽  
Vol 52 (2) ◽  
pp. 457-464 ◽  
Author(s):  
Francisco Luiz Gumes Lopes ◽  
João Baptista Severo Júnior ◽  
Roberto Rodrigues de Souza ◽  
Daniela Diniz Ehrhardt ◽  
José Carlos Curvelo Santana ◽  
...  
Keyword(s):  
Proteolytic Activity ◽  
Membrane Separation ◽  
Ananas Comosus ◽  
Transmembrane Pressure ◽  
Operation Condition ◽  
Separation Processes ◽  
Pineapple Juice ◽  
Experimental Planning ◽  
Ultra Filtration ◽  
Pineapple Pulp

The concentration of pineapple juice is needed to retain the bromelain activity and to standardize the composition and proteolytic activity. Thus, this work aimed to obtain a pure bromelain extract from the Ananas comosus L. Merril juice by membrane separation process. A 2² experimental planning was used to study the influence of pH and transmembrane pressure on the activity recovery by micro-filtration using a plain membrane. In second step, this enzyme was purified by the ultra-filtration using a 10 kDa millipore kit. The best operation condition to bromelain concentration using the plain membrane was at pH 7.5 and transmembrane pressure of 0.05 bar, while 85% of bromelain activity was recovered. Ultra-filtration retained 100% of proteolytic activity and concentrated in 10 fold the bromelain extract. SDS-PAGE electrophoresis showed that the ultra-filtrated had high purity and the bromelain from A. comosus pulp had a molecular weight of 24.5 kDa.

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