scholarly journals Characterization of a New Rhamnolipid Biosurfactant Complex from Pseudomonas Isolate DYNA270

Biomolecules ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 885 ◽  
Author(s):  
Gina S. Shreve ◽  
Ronald Makula
Keyword(s):  
Critical Micelle Concentration ◽  
Interfacial Tension ◽  
Physical Properties ◽  
Carbon Number ◽  
Culture Broth ◽  
Stoichiometric Ratio ◽  
Interface Tension ◽  
Ph Optimum ◽  
Rhodococcus Species ◽  
Pseudomonas Species

The chemical and physical properties of extracellular rhamnolipid synthesized by a nonfluorescent Pseudomonas species soil isolate, identified as DYNA270, is described, along with characteristics of rhamnolipid production under varying growth conditions and substrates. The biosurfactant is determined to be an anionic, extracellular glycolipid consisting of two major components, the rhamnopyranoside β-1-3-hydroxydecanoyl-3-hydroxydecanoic acid (GU-6) and rhamnopyranosyl β→β2-rhamnopyranoside-β1-3-hydroxydecanoyl-3-hydroxydecanoic acid (GL-2), of molecular weight 504 and 649 daltons, respectively. These glycolipids are produced in a stoichiometric ratio of 1:3, respectively. The purified rhamnolipid mixture exhibits a critical micelle concentration of 20 mg/L, minimum surface (air/water interface) tension of 22 mN/m, and minimum interfacial tension values of 0.005 mN/m (against hexane). The pH optimum, critical micelle concentration, and effective alkane carbon number were established for Pseudomonas species DYNA270 and compared to those of rhamnolipid produced by Pseudomonas aeruginosa PG201. Significant differences are documented in the physical properties of extracellular rhamnolipids derived from these two microorganisms. The surface properties of this rhamnolipid are unique in that ultra-low surface and interfacial tension values are present in both purified rhamnolipid and culture broth containing the rhamnolipid complex (GU6 and GL2). We are not aware of prior studies reporting surface activity values this low for rhamnolipids. An exception is noted for an extracellular trehalose glycolipid produced by Rhodococcus species H13-A, which measured 0.00005 mN/m in the presence of the co-agent pentanol (Singer et al. 1990). Similar CMC values of 20 mg/L have been reported for rhamnolipids, a few being recorded as 5–10 mg/L for Pseudomonas species DSM2874 (Lang et al. 1984).

Solution Properties and Phase Behavior of Ammonium Hexylene Octyl Succinate in Water and Water-Oil System

1970 ◽  
Vol 3 (1) ◽  
Author(s):  
Md. Hamidul Kabir ◽  
Ravshan Makhkamov ◽  
Shaila Kabir
Keyword(s):  
Critical Micelle Concentration ◽  
Phase Behavior ◽  
Liquid Crystalline ◽  
Carbon Number ◽  
Phase Region ◽  
Solution Properties ◽  
Middle Phase ◽  
Two Phase ◽  
Lamellar Liquid Crystal ◽  
Drug Ingredient

The solution properties and phase behavior of ammonium hexylene octyl succinate (HOS) was investigated in water and water-oil system. The critical micelle concentration (CMC) of HOS is lower than that of anionic surfactants having same carbon number in the lipophilic part. The phase diagrams of a water/ HOS system and water/ HOS/ C10EO8/ dodecane system were also constructed. Above critical micelle concentration, the surfactant forms a normal micellar solution (Wm) at a low surfactant concentration whereas a lamellar liquid crystalline phase (La) dominates over a wide region through the formation of a two-phase region (La+W) in the binary system. The lamellar phase is arranged in the form of a biocompatible vesicle which is very significant for the drug delivery system. The surfactant tends to be hydrophilic when it is mixed with C10EO8 and a middle-phase microemulsion (D) is appeared in the water-surfactant-dodecane system where both the water and oil soluble drug ingredient can be incorporated in the form of a dispersion. Hence, mixing can tune the hydrophile-lipophile properties of the surfactant. Key words: Ammonium hexylene octyl succinate, mixed surfactant, lamellar liquid crystal, middle-phase microemulsion. Dhaka Univ. J. Pharm. Sci. Vol.3(1-2) 2004 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website

scholarly journals The Importance of Microemulsion for the Surfactant Injection Process in Enhanced Oil Recovery

2021 ◽  
Author(s):  
Rini Setiati ◽  
Muhammad Taufiq Fathaddin ◽  
Aqlyna Fatahanissa
Keyword(s):  
Interfacial Tension ◽  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Recovery Process ◽  
Injection System ◽  
Type I ◽  
Middle Phase ◽  
Interface Tension ◽  
Lower Phase ◽  
Injection Process

Microemulsion is the main parameter that determines the performance of a surfactant injection system. According to Myers, there are four main mechanisms in the enhanced oil recovery (EOR) surfactant injection process, namely interface tension between oil and surfactant, emulsification, decreased interfacial tension and wettability. In the EOR process, the three-phase regions can be classified as type I, upper-phase emulsion, type II, lower-phase emulsion and type III, middle-phase microemulsion. In the middle-phase emulsion, some of the surfactant grains blend with part of the oil phase so that the interfacial tension in the area is reduced. The decrease in interface tension results in the oil being more mobile to produce. Thus, microemulsion is an important parameter in the enhanced oil recovery process.

scholarly journals Synthesis of Guerbet Amine-Oxide for Enhanced Oil Recovery

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Changxin Shi ◽  
Zhiping Li ◽  
Hong Zhang ◽  
Yajuan Chen ◽  
Minglong Zhang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Binary System ◽  
Critical Micelle Concentration ◽  
Interfacial Tension ◽  
Oil Recovery ◽  
Mass Spectra ◽  
Amine Oxide ◽  
The Core ◽  
Ft Ir ◽  
Core Flood

Guerbet amine-oxide was synthesized by using Guerbet acid, N,N′-diethyl-1,3-propanediamine and hydrogen peroxide. Its structure was confirmed by FT-IR spectra and mass spectra. The critical micelle concentration (CMC) and the interfacial tension between the crude oil and water were measured. The results showed that the CMC of the Guerbet amine-oxide is 2.14 × 10−5 mol/L and the interfacial tension could be lowered to ultralow levels. The core flood test showed that the surfactant and polymer binary system could increase oil recovery by 24.7% above the water flood.

scholarly journals The influence of the solveny medium on the aggregation of asphaltene macromolecules and determination of their molar mass

2008 ◽  
Vol 2 (2) ◽  
pp. 91-97
Author(s):  
Antonieta Middea ◽  
◽  
Marisa Bezerra de Mello Monte ◽  
Elizabete Fernandes Lucas ◽  
◽  
...  
Keyword(s):  
Critical Micelle Concentration ◽  
Interfacial Tension ◽  
Crude Oil ◽  
Kinematic Viscosity ◽  
Molar Mass ◽  
Solubility Parameters ◽  
Organic Solutions

The formation of aggregates of a fraction of asphaltenes extracted from Brazilian crude oil was investigated by measuring the interfacial tension and kinematic viscosity of their solutions prepared in different solvents. The interfacial tension results indicate the existence of critical micelle concentration (CMC) levels of the asphaltenes in solvents with solubility parameters sufficiently different from those of the asphaltene tested. The kinematic viscosity measures revealed the formation of aggregates at concentrations above the CMC. The interfacial tension measures of asphaltenes in organic solutions, although infrequently mentioned in the literature, were used to calculate the molar mass, permitting the comparison of various molar masses attributed to the asphaltenes in the form of aggregates.

Parametric Study of Droplet Formation and Characteristics Within Microfluidic Devices — A Case Study

2020 ◽  
Vol 12 (07) ◽  
pp. 2050077
Author(s):  
Seyedeh Sarah Salehi ◽  
Amir Shamloo ◽  
Siamak Kazemzadeh Hannani
Keyword(s):  
Interfacial Tension ◽  
Physical Properties ◽  
Flow Rate ◽  
Viscosity Ratio ◽  
Droplet Formation ◽  
Continuous Phase ◽  
Phase Flow ◽  
Phase Density ◽  
Size And Shape ◽  
The Impact

Droplet-based microfluidics technologies hold great attention in a wide range of applications, including chemical analysis, drug screening, and food industries. This work aimed to describe the effects of different physical properties of the two immiscible phases on droplet formation in a flow-focusing microfluidic device and determining proper flow rates to form a droplet within the desired size range. A numerical model was developed to solve the governing equations of two-phase flow and the results were validated with previous experimental results. The results demonstrate different types of droplet formation regimes from dripping to jetting and different production rates of droplets as a consequence of the impact of each property on fluid flow, including the viscosity ratio, density, interfacial tension, and the flow rate ratio. Based on the results, flow rate, viscosity, and interfacial tension strongly affect the droplet formation regime as well as its size and shape. Droplet diameter increases by increasing the dispersed to continuous phase flow rate as well as the interfacial tension while it decreases by increasing the viscosity ratio and the continuous phase density. Moreover, the formation of satellite droplets was modeled, and the effect of interfacial tension, the viscosity of the dispersed phase and the continuous phase density were found to be important on the conditions that the satellite droplets are suppressed. Since the formation of the satellite droplets induces polydispersity in droplet size, this phenomenon is avoided. Collectively, choosing appropriate aqueous and oil phases with proper physical properties is crucial in forming monodisperse droplets with defined size and shape.

scholarly journals Effect of Surface and Interfacial Tension on the Resonance Frequency of Microfluidic Channel Cantilever

Sensors ◽  
2020 ◽  
Vol 20 (22) ◽  
pp. 6459
Author(s):  
Rosmi Abraham ◽  
Faheem Khan ◽  
Syed A. Bukhari ◽  
Qingxia Liu ◽  
Thomas Thundat ◽  
...  
Keyword(s):  
Interfacial Tension ◽  
Resonance Frequency ◽  
Laser Doppler Vibrometer ◽  
Microfluidic Channel ◽  
Interface Tension ◽  
Near Surface ◽  
Surface And Interface ◽  
Interface Layers ◽  
Extra Stress ◽  
Effect Of Surface

The bending resonance of micro-sized resonators has been utilized to study adsorption of analyte molecules in complex fluids of picogram quantity. Traditionally, the analysis to characterize the resonance frequency has focused solely on the mass change, whereas the effect of interfacial tension of the fluid has been largely neglected. By observing forced vibrations of a microfluidic cantilever filled with a series of alkanes using a laser Doppler vibrometer (LDV), we studied the effect of surface and interfacial tension on the resonance frequency. Here, we incorporated the Young–Laplace equation into the Euler–Bernoulli beam theory to consider extra stress that surface and interface tension exerts on the vibration of the cantilever. Based on the hypothesis that the near-surface region of a continuum is subject to the extra stress, thin surface and interface layers are introduced to our model. The thin layer is subject to an axial force exerted by the extra stress, which in turn affects the transverse vibration of the cantilever. We tested the analytical model by varying the interfacial tension between the silicon nitride microchannel cantilever and the filled alkanes, whose interfacial tension varies with chain length. Compared with the conventional Euler–Bernoulli model, our enhanced model provides a better agreement to the experimental results, shedding light on precision measurements using micro-sized cantilever resonators.

Effect of Nanocellulose on Water-Oil Interfacial Tension

2021 ◽  
Vol 874 ◽  
pp. 13-19
Author(s):  
Mia Ledyastuti ◽  
Joseph Jason ◽  
Reza Aditama
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Interfacial Tension ◽  
Density Profile ◽  
Oil Recovery ◽  
Pure Water ◽  
Dynamics Simulation ◽  
Interface Tension ◽  
Determinant Factor ◽  
Natural Emulsifier

Interfacial tension is an important parameter in enhanced oil recovery (EOR). The interaction between water and oil phase is a determinant factor of the interfacial tension. The interfacial tension changes if another component is added to the water-oil system. This study investigates the effect of adding nanocellulose to the water-oil system. To determine the molecular interactions that occur, a molecular dynamics simulation was carried out using the GROMACS-2018 software. The simulation shows that addition of nanocellulose slightly decreases the water-oil interface tension. Further, based on the density profile, nanocellulose may act as an emulsifier due to its geometric position in the water-oil interface. This is similar to asphaltene, which is a natural emulsifier in crude oil. The nanocellulose performs better in the presence of 1% NaCl as compared to pure water.

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