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Zhang Y, Xiu J, Yi L, Liao G, Yu L, Huang L. Simulation Study on Molecular Behavior of Rhamnolipids and Biobased Zwitterionic Surfactants at the Oil/Water Interface: Effect of Rhamnose Moiety Structures. ACS OMEGA 2023; 8:36655-36661. [PMID: 37841126 PMCID: PMC10568577 DOI: 10.1021/acsomega.3c02253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 09/08/2023] [Indexed: 10/17/2023]
Abstract
Molecular behavior of rhamnolipid mixed with a biobased zwitterionic surfactant at an n-hexadecane/water interface has been studied, and the effects of a rhamnose moiety and composition are evaluated. Results showed that rhamnolipid abundantly interacts with biobased surfactant EAB by means of hydrophobic interactions between aliphatic tails and electrostatic interactions between headgroups, including the attractive interaction between COO- of rhamnolipids and N+ of biobased surfactants and the repulsive interaction between COO- of both surfactants. Dirhamnolipid has a larger number of bound Na+ and a more stable bound structure of COO- ∼ Na+, which screens the repulsive interaction between two kinds of surfactants and shows a more homogeneous distribution with biobased surfactants. The interfacial tension between n-hexadecane and water has been synergistically reduced by dirhamnolipids mixed with biobased surfactants at a higher molar ratio of biobased surfactants. Monorhamnolipids show a strengthened interaction with N+ of biobased surfactants and a more stable hydrogen bond with water relative to that of dirhamnolipids, and there is no synergistic effect in lowering the interfacial tension for the mixture of monorhamnolipids and biobased surfactants. The present work provides details of the molecular behavior of biosurfactant rhamnolipids mixed with biobased surfactants and obtains the key factor in affecting the interfacial properties of the binary system.
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Affiliation(s)
- Yamiao Zhang
- University
of Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- Institute
of Porous Flow and Fluid Mechanics, Chinese Academy of Sciences, Langfang 065007, Hebei Province, People’s
Republic of China
- PetroChina
Research Institute of Petroleum Exploration and Development, Beijing 100083, People’s Republic of China
| | - Jianlong Xiu
- PetroChina
Research Institute of Petroleum Exploration and Development, Beijing 100083, People’s Republic of China
| | - Lina Yi
- PetroChina
Research Institute of Petroleum Exploration and Development, Beijing 100083, People’s Republic of China
| | - Guangzhi Liao
- PetroChina
Exploration and Production Company, Beijing 100120, People’s Republic of China
| | - Li Yu
- PetroChina
Research Institute of Petroleum Exploration and Development, Beijing 100083, People’s Republic of China
| | - Lixin Huang
- PetroChina
Research Institute of Petroleum Exploration and Development, Beijing 100083, People’s Republic of China
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2
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Rhamnolipid Self-Aggregation in Aqueous Media: A Long Journey toward the Definition of Structure–Property Relationships. Int J Mol Sci 2023; 24:ijms24065395. [PMID: 36982468 PMCID: PMC10048978 DOI: 10.3390/ijms24065395] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 03/16/2023] Open
Abstract
The need to protect human and environmental health and avoid the widespread use of substances obtained from nonrenewable sources is steering research toward the discovery and development of new molecules characterized by high biocompatibility and biodegradability. Due to their very widespread use, a class of substances for which this need is particularly urgent is that of surfactants. In this respect, an attractive and promising alternative to commonly used synthetic surfactants is represented by so-called biosurfactants, amphiphiles naturally derived from microorganisms. One of the best-known families of biosurfactants is that of rhamnolipids, which are glycolipids with a headgroup formed by one or two rhamnose units. Great scientific and technological effort has been devoted to optimization of their production processes, as well as their physicochemical characterization. However, a conclusive structure–function relationship is far from being defined. In this review, we aim to move a step forward in this direction, by presenting a comprehensive and unified discussion of physicochemical properties of rhamnolipids as a function of solution conditions and rhamnolipid structure. We also discuss still unresolved issues that deserve further investigation in the future, to allow the replacement of conventional surfactants with rhamnolipids.
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3
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Rhamnolipid–SLES aqueous mixtures: From the molecular self-aggregation to the functional and ecotoxicological properties. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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4
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Rekiel E, Zdziennicka A, Szymczyk K, Jańczuk B. Wetting Properties of Rhamnolipid and Surfactin Mixtures with Triton X-165. Molecules 2022; 27:molecules27154706. [PMID: 35897880 PMCID: PMC9330438 DOI: 10.3390/molecules27154706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 12/10/2022] Open
Abstract
The wetting properties of the rhamnolipid and surfactin mixtures with Triton X-165 were considered based on the contact angle measurements of their aqueous solution on the polytetrafluoroethylene (PTFE), polymethyl methacrylate (PMMA) and quartz (Q) surfaces. The obtained contact angle isotherms were described by the exponential function of the second order as well as by Szyszkowski equation in some cases. Using the contact angle isotherms of individual biosurfactants and TX165 as well as the earlier obtained isotherms of their surface tension the contact angle isotherms of the biosurfactants mixtures with TX165 were deduced. As follows the presence of the maxima on the contact angle isotherms of the biosurfactants mixtures with TX165 is justified. They do not prove negative adsorption of the biosurfactant and TX165 at the interfaces. However, the mutual exchange of the biosurfactant and TX165 molecules is observed in the layers at the interfaces. The concentration of the studied mixtures at the PTFE-solution interface was established to be close to that at the solution-air one but that at the PTFE-air is equal to zero. However, the concentration of the studied mixtures at the PMMA-solution and quartz-solution is greater than zero. The concentration at the PMMA(quartz)-air and PMMA(quartz)-solution interfaces is smaller than that at the solution-air one.
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5
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Weng T, Wang L, Liu Y, Zhang X, Wu Y, Zhang Y, Han J, Liu M. Interaction of bisdemethoxycurcumin with sodium dodecyl sarcosine + Tween 20/Tween 60 mixed surfactants: Insights from multispectral analysis and solubilization effect. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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6
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Thermodynamic Analysis of the Adsorption and Micellization Activity of the Mixtures of Rhamnolipid and Surfactin with Triton X-165. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27113600. [PMID: 35684536 PMCID: PMC9182474 DOI: 10.3390/molecules27113600] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 05/30/2022] [Accepted: 05/31/2022] [Indexed: 11/17/2022]
Abstract
The surface tension of aqueous solutions of Triton X-165 with rhamnolipid or surfactin mixtures was measured. The obtained results were applied for the determination of the concentration and composition of the Triton X-165 and biosurfactants mixture at the water-air interface as well as the contribution of the particular component of the mixtures to water surface tension reduction and the mutual influence of these components on the critical micelle concentration. The determination of these quantities was based on both the commonly used concepts and a new one proposed by us, which assumes that the composition of the mixed monolayer at the water-air interface depends directly on the pressure of the monolayer of the single mixture component and allows us to determine the surface concentration of each mixture component independently of surface tension isotherms shape. Taking into account the composition of the mixed monolayer at the water-air interface, the standard Gibbs adsorption free energy was considered. The obtained results allow us to state that the concentration of both mixture components corresponding to their saturated monolayer and the surface tension of their aqueous solution can be predicted using the surfactants' single monolayer pressure and their mole fraction in the mixed monolayer determined in the proposed way.
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7
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Chen IC, Lee MT. Rhamnolipid Biosurfactants for Oil Recovery: Salt Effects on the Structural Properties Investigated by Mesoscale Simulations. ACS OMEGA 2022; 7:6223-6237. [PMID: 35224385 PMCID: PMC8867548 DOI: 10.1021/acsomega.1c06741] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
Rhamnolipids (RLs) are biosurfactants produced by Pseudomonas. The biodegradability and the variety of their functionality make them suitable for environmental remediation and oil recovery. We use dissipative particle dynamics simulations to investigate the aggregation behaviors of ionic RL congeners with nonane in various operating conditions. Under zero-salinity conditions, all RL congeners studied here form small ellipsoidal clusters with detectable free surfactants. When salt ions are present, the electrostatic repulsion between the ionized heads is overcome, resulting in the formation of larger aggregates of unique structures. RLs with C10-alkyl tails tend to form elongated wormlike micelles, while RLs with C16-alkyl tails tend to form clusters in spherical symmetry, including vesicles. Di-rhamnolipids (dRLs) require stronger solvation than monorhamnolipids (mRLs) to form clusters, and the resulting size of micelles is decreased. The morphology of the mixed dRL/mRL/oil systems is controlled based on the type of the congeners and the oil contents. In addition, the divalent calcium ions are found to be influential to the structure of the micelles through different mechanisms. For 5 wt % salinity, the ionic RLs can form oil-swollen micelles up to a 1:1 surfactant-to-oil ratio, suggesting that ionic RLs are superb to act as cleaning agents for petroleum hydrocarbons in the marine area. These key findings may guide the design for RL-based washing techniques in enhanced oil recovery.
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Affiliation(s)
- I-Chin Chen
- Department of Chemical Engineering
and Biotechnology, National Taipei University
of Technology, Taipei 10608, Taiwan
| | - Ming-Tsung Lee
- Department of Chemical Engineering
and Biotechnology, National Taipei University
of Technology, Taipei 10608, Taiwan
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8
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Allegrone G, Ceresa C, Rinaldi M, Fracchia L. Diverse Effects of Natural and Synthetic Surfactants on the Inhibition of Staphylococcus aureus Biofilm. Pharmaceutics 2021; 13:1172. [PMID: 34452132 PMCID: PMC8402037 DOI: 10.3390/pharmaceutics13081172] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 12/25/2022] Open
Abstract
A major challenge in the biomedical field is the creation of materials and coating strategies that effectively limit the onset of biofilm-associated infections on medical devices. Biosurfactants are well known and appreciated for their antimicrobial/anti-adhesive/anti-biofilm properties, low toxicity, and biocompatibility. In this study, the rhamnolipid produced by Pseudomonas aeruginosa 89 (R89BS) was characterized by HPLC-MS/MS and its ability to modify cell surface hydrophobicity and membrane permeability as well as its antimicrobial, anti-adhesive, and anti-biofilm activity against Staphylococcus aureus were compared to two commonly used surfactants of synthetic origin: Tween® 80 and TritonTM X-100. The R89BS crude extract showed a grade of purity of 91.4% and was composed by 70.6% of mono-rhamnolipids and 20.8% of di-rhamnolipids. The biological activities of R89BS towards S. aureus were higher than those of the two synthetic surfactants. In particular, the anti-adhesive and anti-biofilm properties of R89BS and of its purified mono- and di-congeners were similar. R89BS inhibition of S. aureus adhesion and biofilm formation was ~97% and 85%, respectively, and resulted in an increased inhibition of about 33% after 6 h and of about 39% after 72 h when compared to their chemical counterparts. These results suggest a possible applicability of R89BS as a protective coating agent to limit implant colonization.
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9
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Luengo GS, Fameau AL, Léonforte F, Greaves AJ. Surface science of cosmetic substrates, cleansing actives and formulations. Adv Colloid Interface Sci 2021; 290:102383. [PMID: 33690071 DOI: 10.1016/j.cis.2021.102383] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 02/04/2021] [Accepted: 02/06/2021] [Indexed: 12/22/2022]
Abstract
The development of shampoo and cleansing formulations in cosmetics is at a crossroads due to consumer demands for better performing, more natural products and also the strong commitment of cosmetic companies to improve the sustainability of cosmetic products. In order to go beyond traditional formulations, it is of great importance to clearly establish the science behind cleansing technologies and appreciate the specificity of cleansing biological surfaces such as hair and skin. In this review, we present recent advances in our knowledge of the physicochemical properties of the hair surface from both an experimental and a theoretical point of view. We discuss the opportunities and challenges that newer, sustainable formulations bring compared to petroleum-based ingredients. The inevitable evolution towards more bio-based, eco-friendly ingredients and sustainable formulations requires a complete rethink of many well-known physicochemical principles. The pivotal role of digital sciences and modelling in the understanding and conception of new ingredients and formulations is discussed. We describe recent numerical approaches that take into account the specificities of the hair surface in terms of structuration, different methods that study the adsorption of formulation ingredients and finally the success of new data-driven approaches. We conclude with practical examples on current formulation efforts incorporating bio-surfactants, controlling foaming and searching for new rheological properties.
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10
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Ceresa C, Fracchia L, Fedeli E, Porta C, Banat IM. Recent Advances in Biomedical, Therapeutic and Pharmaceutical Applications of Microbial Surfactants. Pharmaceutics 2021; 13:466. [PMID: 33808361 PMCID: PMC8067001 DOI: 10.3390/pharmaceutics13040466] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/18/2021] [Accepted: 03/23/2021] [Indexed: 12/19/2022] Open
Abstract
The spread of antimicrobial-resistant pathogens typically existing in biofilm formation and the recent COVID-19 pandemic, although unrelated phenomena, have demonstrated the urgent need for methods to combat such increasing threats. New avenues of research for natural molecules with desirable properties to alleviate this situation have, therefore, been expanding. Biosurfactants comprise a group of unique and varied amphiphilic molecules of microbial origin capable of interacting with lipidic membranes/components of microorganisms and altering their physicochemical properties. These features have encouraged closer investigations of these microbial metabolites as new pharmaceutics with potential applications in clinical, hygiene and therapeutic fields. Mounting evidence has indicated that biosurfactants have antimicrobial, antibiofilm, antiviral, immunomodulatory and antiproliferative activities that are exploitable in new anticancer treatments and wound healing applications. Some biosurfactants have already been approved for use in clinical, food and environmental fields, while others are currently under investigation and development as antimicrobials or adjuvants to antibiotics for microbial suppression and biofilm eradication strategies. Moreover, due to the COVID-19 pandemic, biosurfactants are now being explored as an alternative to current products or procedures for effective cleaning and handwash formulations, antiviral plastic and fabric surface coating agents for shields and masks. In addition, biosurfactants have shown promise as drug delivery systems and in the medicinal relief of symptoms associated with SARS-CoV-2 acute respiratory distress syndrome.
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Affiliation(s)
- Chiara Ceresa
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “A. Avogadro”, 28100 Novara, Italy; (C.C.); (E.F.); (C.P.)
| | - Letizia Fracchia
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “A. Avogadro”, 28100 Novara, Italy; (C.C.); (E.F.); (C.P.)
| | - Emanuele Fedeli
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “A. Avogadro”, 28100 Novara, Italy; (C.C.); (E.F.); (C.P.)
| | - Chiara Porta
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “A. Avogadro”, 28100 Novara, Italy; (C.C.); (E.F.); (C.P.)
- Center for Translational Research on Autoimmune & Allergic Diseases (CAAD), Università del Piemonte Orientale “A. Avogadro”, 28100 Novara, Italy
| | - Ibrahim M. Banat
- Pharmaceutical Science Research Group, Biomedical Science Research Institute, Ulster University, Coleraine, Northern Ireland BT52 1SA, UK;
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11
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Gang H, Bian P, He X, He X, Bao X, Mu B, Li Y, Yang S. Mixing of Surfactin, an Anionic Biosurfactant, with Alkylbenzene Sulfonate, a Chemically Synthesized Anionic Surfactant, at the
n
‐Decane
/Water Interface. J SURFACTANTS DETERG 2021. [DOI: 10.1002/jsde.12495] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Hong‐Ze Gang
- State Key Laboratory of Bioreactor Engineering and School of Chemistry and Molecular Engineering and Engineering Research Center of Microbial Enhanced Oil Recovery, MOE East China University of Science and Technology Shanghai 200237 China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology Shanghai 200237 China
| | - Peng‐Cheng Bian
- State Key Laboratory of Bioreactor Engineering and School of Chemistry and Molecular Engineering and Engineering Research Center of Microbial Enhanced Oil Recovery, MOE East China University of Science and Technology Shanghai 200237 China
| | - Xiuli He
- State Key Laboratory of Bioreactor Engineering and School of Chemistry and Molecular Engineering and Engineering Research Center of Microbial Enhanced Oil Recovery, MOE East China University of Science and Technology Shanghai 200237 China
| | - Xiujuan He
- Sinopec Key Lab of Surfactants for EOR Sinopec Shanghai Research Institute of Petrochemical Technology North Pudong 1658 Shanghai 201208 China
| | - Xinning Bao
- State Key Laboratory of Bioreactor Engineering and School of Chemistry and Molecular Engineering and Engineering Research Center of Microbial Enhanced Oil Recovery, MOE East China University of Science and Technology Shanghai 200237 China
- Sinopec Key Lab of Surfactants for EOR Sinopec Shanghai Research Institute of Petrochemical Technology North Pudong 1658 Shanghai 201208 China
| | - Bo‐Zhong Mu
- State Key Laboratory of Bioreactor Engineering and School of Chemistry and Molecular Engineering and Engineering Research Center of Microbial Enhanced Oil Recovery, MOE East China University of Science and Technology Shanghai 200237 China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology Shanghai 200237 China
| | - Yingcheng Li
- Sinopec Key Lab of Surfactants for EOR Sinopec Shanghai Research Institute of Petrochemical Technology North Pudong 1658 Shanghai 201208 China
| | - Shi‐Zhong Yang
- State Key Laboratory of Bioreactor Engineering and School of Chemistry and Molecular Engineering and Engineering Research Center of Microbial Enhanced Oil Recovery, MOE East China University of Science and Technology Shanghai 200237 China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology Shanghai 200237 China
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12
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Liu J, Wang Y, Li H. Synergistic Solubilization of Phenanthrene by Mixed Micelles Composed of Biosurfactants and a Conventional Non-Ionic Surfactant. Molecules 2020; 25:molecules25184327. [PMID: 32967248 PMCID: PMC7570535 DOI: 10.3390/molecules25184327] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/18/2020] [Accepted: 09/20/2020] [Indexed: 01/06/2023] Open
Abstract
This study investigated the solubilization capabilities of rhamnolipids biosurfactant and synthetic surfactant mixtures for the application of a mixed surfactant in surfactant-enhanced remediation. The mass ratios between Triton X-100 and rhamnolipids were set at 1:0, 9:1, 3:1, 1:1, 1:3, and 0:1. The ideal critical micelle concentration values of the Triton X-100/rhamnolipids mixture system were higher than that of the theoretical predicted value suggesting the existence of interactions between the two surfactants. Solubilization capabilities were quantified in term of weight solubilization ratio and micellar-water partition coefficient. The highest value of the weight solubilization ratio was detected in the treatment where only Triton X-100 was used. This ratio decreased with the increase in the mass of rhamnolipids in the mixed surfactant systems. The parameters of the interaction between surfactants and the micellar mole fraction in the mixed system have been determined. The factors that influence phenanthrene solubilization, such as pH, ionic strength, and acetic acid concentration have been discussed in the paper. The aqueous solubility of phenanthrene increased linearly with the total surfactant concentration in all treatments. The mixed rhamnolipids and synthetic surfactants showed synergistic behavior and enhanced the solubilization capabilities of the mixture, which would extend the rhamnolipids application.
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13
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Drakontis CE, Amin S. Biosurfactants: Formulations, properties, and applications. Curr Opin Colloid Interface Sci 2020. [DOI: 10.1016/j.cocis.2020.03.013] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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14
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Penfold J, Thomas R. Adsorption properties of plant based bio-surfactants: Insights from neutron scattering techniques. Adv Colloid Interface Sci 2019; 274:102041. [PMID: 31655367 DOI: 10.1016/j.cis.2019.102041] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 09/30/2019] [Accepted: 09/30/2019] [Indexed: 01/16/2023]
Abstract
There is an increasing interest in biosustainable surfactants and surface active proteins for a range of applications, in home and personal care products, cosmetics, pharmaceuticals, and food and drink formulations. This review focuses on two plant derived biosurfactants, the surface active glycoside, saponin, and the surface active globular protein, hydrophobin. A particular emphasis in the review is on the role of neutron reflectivity in probing the adsorption, structure of the adsorbed layer, and their mixing at the interface with a range of more conventional surfactants and proteins.
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15
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Smith C, Lu JR, Thomas RK, Tucker IM, Webster JRP, Campana M. Markov Chain Modeling of Surfactant Critical Micelle Concentration and Surface Composition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:561-569. [PMID: 30540480 DOI: 10.1021/acs.langmuir.8b03624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A Markov chain (MC) model has been used to model the following binary surfactant mixtures: linear alkylbenzenesulfonate (LAS4)/octaethylene glycol monododecyl ether (C12E8) at 10 and 25 °C, LAS6/acidic sophorolipid (AS), C12Betaine/C12Maltoside, sodium lauryl ether sulfate (SLES2)/C12E8, and rhamnolipid (R1)/LAS6. The critical micellar concentration and the composition of the adsorbed layer, for each system, can be modeled using the same monomer reactivity ratio values, g1 and g2. This implies that the interactions between the surfactants in the bulk solution and at the interface are the same, within error. For the LAS4/C12E8 system at 25 °C, the ranges of g1 and g2 values which can model both sets of data are within 0.03-0.05 and 1.55-2.10, respectively; g1 ≪ g2 implies that C12E8 is significantly more surface active than LAS4. The MC model indicates a negative change in the free energy upon mixing for all of the surfactant systems, consistent with the literature. The interfacial mixing behavior of LAS4/SLES2 is inferred from the results of the MC analysis of the LAS4/C12E8 and SLES2/C12E8 systems, which share a common surfactant partner in C12E8, and the prediction is in line with the published data.
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Affiliation(s)
- Charles Smith
- Biological Physics Laboratory, School of Physics and Astronomy , University of Manchester , Schuster Building, Oxford Road , Manchester M13 9PL , U.K
| | - Jian Ren Lu
- Biological Physics Laboratory, School of Physics and Astronomy , University of Manchester , Schuster Building, Oxford Road , Manchester M13 9PL , U.K
| | - Robert K Thomas
- Physical and Theoretical Chemistry Laboratory , University of Oxford , South Parks Road , Oxford OX1 3QZ , U.K
| | - Ian M Tucker
- Unilever Research and Development Port Sunlight Laboratory, Quarry Road East , Bebington , Wirral CH63 3JW , U.K
| | - John R P Webster
- STFC , Rutherford Appleton Laboratory , Chilton, Didcot , Oxfordshire OX11 0QX , U.K
| | - Mario Campana
- STFC , Rutherford Appleton Laboratory , Chilton, Didcot , Oxfordshire OX11 0QX , U.K
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16
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Liley J, Penfold J, Thomas R, Tucker I, Petkov J, Stevenson P, Banat I, Marchant R, Rudden M, Webster J. The performance of surfactant mixtures at low temperatures. J Colloid Interface Sci 2019; 534:64-71. [DOI: 10.1016/j.jcis.2018.08.099] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/24/2018] [Accepted: 08/27/2018] [Indexed: 11/17/2022]
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17
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Mortensen HG, Madsen JK, Andersen KK, Vosegaard T, Deen GR, Otzen DE, Pedersen JS. Myoglobin and α-Lactalbumin Form Smaller Complexes with the Biosurfactant Rhamnolipid Than with SDS. Biophys J 2018; 113:2621-2633. [PMID: 29262357 DOI: 10.1016/j.bpj.2017.10.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 09/18/2017] [Accepted: 10/10/2017] [Indexed: 11/16/2022] Open
Abstract
Biosurfactants (BSs) attract increasing attention as sustainable alternatives to petroleum-derived surfactants. This necessitates structural insight into how BSs interact with proteins encountered by current chemical surfactants. Thus, small-angle x-ray scattering (SAXS) has been used for studying the structures of complexes made of the proteins α-Lactalbumin (αLA) and myoglobin (Mb) with the biosurfactant rhamnolipid (RL). For comparison, complexes between αLA and the chemical surfactant sodium dodecyl sulfate (SDS) were also investigated. The SAXS data for pure RL micelles can be described by prolate core-shell structures with a core radius of 7.7 Å and a shell thickness of 12 Å, giving an aggregation number of 11. The small core radius is attributed to RL's complex hydrophobic tail. Data for the αLA-RL complex agree with a 12-molecule micelle with a single protein molecule in the shell. For Mb-RL, the analysis gives complexes of two connected micelles, each containing 10 RL and one protein in the shells. αLA-RL and Mb-RL form surfactant-saturated complexes above 5.6 and 4.7 mM RL, respectively, leaving the remaining RL in free micelles. The SAXS data for SDS agree with oblate-shaped micelles with a core of 20 Å, core eccentricity 0.7, and shell thickness of 5.45 Å, with an aggregation number of 74. The αLA-SDS complexes contain a prolate micelle with a core radius of 11-14 Å and a shell of 8-12 Å with up to 3 αLA per particle and up to 43 SDS per αLA, both considerably larger than for RL. Unlike the RL-protein complexes, the number of surfactant molecules in αLA-SDS complexes increases with surfactant concentration, and saturate at higher surfactant concentrations than αLA-RL complexes. The results highlight how RL and SDS follow similar overall rules of self-assembly and interactions with proteins, but that differences in the strength of protein-surfactant interactions affect the formed structures.
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Affiliation(s)
- Henriette Gavlshøj Mortensen
- Interdisciplinary Nanoscience Center iNANO, Aarhus University, Aarhus C, Denmark; Department of Chemistry, Aarhus University, Aarhus C, Denmark
| | - Jens Kvist Madsen
- Interdisciplinary Nanoscience Center iNANO, Aarhus University, Aarhus C, Denmark
| | - Kell K Andersen
- Interdisciplinary Nanoscience Center iNANO, Aarhus University, Aarhus C, Denmark
| | - Thomas Vosegaard
- Interdisciplinary Nanoscience Center iNANO, Aarhus University, Aarhus C, Denmark; Department of Chemistry, Aarhus University, Aarhus C, Denmark
| | - G Roshan Deen
- Natural Sciences and Science Education, Nanyang Technological University, Singapore, Singapore
| | - Daniel E Otzen
- Interdisciplinary Nanoscience Center iNANO, Aarhus University, Aarhus C, Denmark; Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark.
| | - Jan Skov Pedersen
- Interdisciplinary Nanoscience Center iNANO, Aarhus University, Aarhus C, Denmark; Department of Chemistry, Aarhus University, Aarhus C, Denmark.
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18
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Liley JR, Thomas RK, Penfold J, Tucker IM, Petkov JT, Stevenson PS, Banat IM, Marchant R, Rudden M, Webster JRP. Adsorption at the Air-Water Interface in Biosurfactant-Surfactant Mixtures: Quantitative Analysis of Adsorption in a Five-Component Mixture. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:13027-13039. [PMID: 29043809 DOI: 10.1021/acs.langmuir.7b03187] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The composition of the air-water adsorbed layer of a quinary mixture consisting of three conventional surfactants, octaethylene glycol monododecyl ether (C12E8), dodecane-6-p-sodium benzene sulfonate (LAS6), and diethylene glycol monododecyl ether sodium sulfate (SLE2S), mixed with two biosurfactants, the rhamnolipids l-rhamnosyl-l-rhamnosyl-β-hydroxydecanoyl-β-hydroxydecanoyl, R2, and l-rhamnosyl-β-hydroxydecanoyl-β-hydroxydecanoyl, R1, has been measured over a range of compositions above the mixed critical micelle concentration. Additional measurements on some of the subsets of ternary and binary mixtures have also been measured by NR. The results have been analyzed using the pseudophase approximation (PPA) in conjunction with an excess free energy, GE, that depends on the quadratic and cubic terms in the composition. The compositions of the binary, ternary, and quinary mixtures could all be fitted to two sets of interaction parameters between the pairs of surfactants, one for micelles and one for adsorption. No ternary interactions or ternary corrections were required. Because the system contains two strongly anionic surfactants, the PPA can be extended, in practice, to ionic surfactants, contrary to the prevailing view. The values of the interaction parameters show that the quinary mixture, SLE2S-LAS6-C12E8-R1-R2, which is known to be a highly effective surfactant system, is characterized by a sequence of strong surface but weak micellar interactions. About half of the minima in GE for the strong surface interactions occur well away from the regular solution value of 0.5.
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Affiliation(s)
- Jessica R Liley
- Physical and Theoretical Chemistry Laboratory , South Parks Road, Oxford OX1 3QZ, U.K
| | - Robert K Thomas
- Physical and Theoretical Chemistry Laboratory , South Parks Road, Oxford OX1 3QZ, U.K
| | - Jeffrey Penfold
- STFC, Rutherford-Appleton Laboratory , Chilton, Didcot, Oxfordshire OX11 0QX, U.K
- Physical and Theoretical Chemistry Laboratory , South Parks Road, Oxford OX1 3QZ, U.K
| | - Ian M Tucker
- Unilever Research and Development Laboratory , Port Sunlight, Quarry Road East, Bebington, Wirral CH63 3JW, U.K
| | - Jordan T Petkov
- Unilever Research and Development Laboratory , Port Sunlight, Quarry Road East, Bebington, Wirral CH63 3JW, U.K
| | - Paul S Stevenson
- Unilever Research and Development Laboratory , Port Sunlight, Quarry Road East, Bebington, Wirral CH63 3JW, U.K
| | - Ibrahim M Banat
- School of Biomedical Sciences, University of Ulster , Coleraine BT52 1SA, Northern Ireland
| | - Roger Marchant
- School of Biomedical Sciences, University of Ulster , Coleraine BT52 1SA, Northern Ireland
| | - M Rudden
- School of Biomedical Sciences, University of Ulster , Coleraine BT52 1SA, Northern Ireland
| | - John R P Webster
- STFC, Rutherford-Appleton Laboratory , Chilton, Didcot, Oxfordshire OX11 0QX, U.K
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19
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Xu J, Wang Z, Gao J, Li C, Sun S, Hu S. Dissipative particle dynamics simulations reveal the pH-driven micellar transition pathway of monorhamnolipids. J Colloid Interface Sci 2017; 506:493-503. [DOI: 10.1016/j.jcis.2017.07.083] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Revised: 07/19/2017] [Accepted: 07/21/2017] [Indexed: 11/30/2022]
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20
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Eismin RJ, Munusamy E, Kegel LL, Hogan DE, Maier RM, Schwartz SD, Pemberton JE. Evolution of Aggregate Structure in Solutions of Anionic Monorhamnolipids: Experimental and Computational Results. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:7412-7424. [PMID: 28737038 PMCID: PMC5767468 DOI: 10.1021/acs.langmuir.7b00078] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The evolution of solution aggregates of the anionic form of the native monorhamnolipid (mRL) mixture produced by Pseudomonas aeruginosa ATCC 9027 is explored at pH 8.0 using both experimental and computational approaches. Experiments utilizing surface tension measurements, dynamic light scattering, and both steady-state and time-resolved fluorescence spectroscopy reveal solution aggregation properties. All-atom molecular dynamics simulations on self-assemblies of the most abundant monorhamnolipid molecule, l-rhamnosyl-β-hydroxydecanoyl-β-hydroxydecanoate (Rha-C10-C10), in its anionic state explore the formation of aggregates and the role of hydrogen bonding, substantiating the experimental results. At pH 8.0, at concentrations above the critical aggregation concentration of 201 μM but below ∼7.5 mM, small premicelles exist in solution; above ∼7.5 mM, micelles with hydrodynamic radii of ∼2.5 nm dominate, although two discrete populations of larger lamellar aggregates (hydrodynamic radii of ∼10 and 90 nm) are also present in solution in much smaller number densities. The critical aggregation number for the micelles is determined to be ∼26 monomers/micelle using fluorescence quenching measurements, with micelles gradually increasing in size with monorhamnolipid concentration. Molecular dynamics simulations on systems with between 10 and 100 molecules of Rha-C10-C10 indicate the presence of stable premicelles of seven monomers with the most prevalent micelle being ∼25 monomers and relatively spherical. A range of slightly larger micelles of comparable stability can also exist that become increasing elliptical with increasing monomer number. Intermolecular hydrogen bonding is shown to play a significant role in stabilization of these aggregates. In total, the computational results are in excellent agreement with the experimental results.
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Affiliation(s)
- Ryan J. Eismin
- Department of Chemistry and Biochemistry, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Elango Munusamy
- Department of Chemistry and Biochemistry, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Laurel L. Kegel
- Department of Chemistry and Biochemistry, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721, United States
| | - David E. Hogan
- Department of Soil, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Raina M. Maier
- Department of Soil, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Steven D. Schwartz
- Department of Chemistry and Biochemistry, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Jeanne E. Pemberton
- Department of Chemistry and Biochemistry, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721, United States
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21
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Composition of Surface Layer at the Water-Air Interface and Micelles of Triton X-100 + Rhamnolipid Mixtures. J SOLUTION CHEM 2017; 46:1251-1271. [PMID: 28680187 PMCID: PMC5488207 DOI: 10.1007/s10953-017-0642-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 03/29/2017] [Indexed: 11/13/2022]
Abstract
Measurements of the surface tensions, densities and viscosities of aqueous solutions of Triton X-100 (TX-100) and rhamnolipid (RL) mixtures, at constant concentration of RL or TX-100, were carried out. The measured values of the surface tension were compared to those determined using different theoretical models and on the basis of the surface tension of aqueous solutions of individual surfactants. From the surface tension isotherms, the Gibbs surface excess concentration of TX-100 and RL, the composition of surface layer and the standard Gibbs free energy of adsorption at the water–air interface were determined. Moreover, on the basis of surface tension, density and viscosity isotherms, the CMC of surfactants mixtures were evaluated. From the density isotherms, apparent and partial molar volumes of TX-100 and RL were also determined. These volumes were compared to those calculated from the sizes of TX-100 and RL molecules. There was observed a synergetic effect in the reduction of water surface tension and micelle formation, which was confirmed by the intermolecular interactions parameter. In the case of micelle formation, this effect was discussed based on the standard Gibbs free energy of micellization as well as of TX-100 and RL mixing in the micelles. The synergism of TX-100 and RL mixtures in the reduction of water surface tension and micelle formation was explained on the basis of electrostatic interactions between the hydrophilic part of TX-100 and RL molecules; this was supported by pH measurements.
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Naeem AH, Mumtaz S, Haleem A, Qazi MA, Malik ZA, Dasti JI, Ahmed S. Isolation and Molecular Characterization of Biosurfactant-Producing Bacterial Diversity of Fimkassar Oil Field, Pakistan. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2017. [DOI: 10.1007/s13369-017-2527-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Palos Pacheco R, Eismin RJ, Coss CS, Wang H, Maier RM, Polt R, Pemberton JE. Synthesis and Characterization of Four Diastereomers of Monorhamnolipids. J Am Chem Soc 2017; 139:5125-5132. [DOI: 10.1021/jacs.7b00427] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Ricardo Palos Pacheco
- Department
of Chemistry and Biochemistry and ‡Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Ryan J. Eismin
- Department
of Chemistry and Biochemistry and ‡Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Clifford S. Coss
- Department
of Chemistry and Biochemistry and ‡Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Hui Wang
- Department
of Chemistry and Biochemistry and ‡Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Raina M. Maier
- Department
of Chemistry and Biochemistry and ‡Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Robin Polt
- Department
of Chemistry and Biochemistry and ‡Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Jeanne E. Pemberton
- Department
of Chemistry and Biochemistry and ‡Department of Soil, Water and Environmental
Science, University of Arizona, Tucson, Arizona 85721, United States
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24
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Euston SR. Molecular simulation of biosurfactants with relevance to food systems. Curr Opin Colloid Interface Sci 2017. [DOI: 10.1016/j.cocis.2017.04.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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25
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Self-assembly in dilute mixtures of non-ionic and anionic surfactants and rhamnolipd biosurfactants. J Colloid Interface Sci 2017; 487:493-503. [DOI: 10.1016/j.jcis.2016.10.071] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 10/24/2016] [Accepted: 10/25/2016] [Indexed: 11/21/2022]
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26
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Li P, Ma K, Thomas RK, Penfold J. Analysis of the Asymmetric Synergy in the Adsorption of Zwitterionic–Ionic Surfactant Mixtures at the Air–Water Interface below and above the Critical Micelle Concentration. J Phys Chem B 2016; 120:3677-91. [DOI: 10.1021/acs.jpcb.6b00762] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Peixun Li
- Physical
and Theoretical Chemistry Laboratory, University of Oxford, South Parks
Road, Oxford, OX1 3QZ, U.K
| | - Kun Ma
- Physical
and Theoretical Chemistry Laboratory, University of Oxford, South Parks
Road, Oxford, OX1 3QZ, U.K
| | - Robert K. Thomas
- Physical
and Theoretical Chemistry Laboratory, University of Oxford, South Parks
Road, Oxford, OX1 3QZ, U.K
| | - Jeffrey Penfold
- Physical
and Theoretical Chemistry Laboratory, University of Oxford, South Parks
Road, Oxford, OX1 3QZ, U.K
- Rutherford-Appleton Laboratory, Science & Technology Facilities Council, Chilton, Didcot, OX11 0QX, U.K
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27
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Díaz De Rienzo MA, Stevenson P, Marchant R, Banat IM. Antibacterial properties of biosurfactants against selected Gram-positive and -negative bacteria. FEMS Microbiol Lett 2015; 363:fnv224. [PMID: 26598715 DOI: 10.1093/femsle/fnv224] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2015] [Indexed: 11/13/2022] Open
Abstract
The antibacterial properties and ability to disrupt biofilms of biosurfactants (rhamnolipids, sophorolipids) and sodium dodecyl sulphate (SDS) in the presence and absence of selected organic acids were investigated. Pseudomonas aeruginosa PAO1 was inhibited by sophorolipids and SDS at concentrations >5% v/v, and the growth of Escherichia coli NCTC 10418 was also inhibited by sophorolipids and SDS at concentrations >5% and 0.1% v/v, respectively. Bacillus subtilis NCTC 10400 was inhibited by rhamnolipids, sophorolipids and SDS at concentrations >0.5% v/v of all three; the same effect was observed with Staphylococcus aureus ATCC 9144. The ability to attach to surfaces and biofilm formation of P. aeruginosa PAO1, E. coli NCTC 10418 and B. subtilis NCTC 10400 was inhibited by sophorolipids (1% v/v) in the presence of caprylic acid (0.8% v/v). In the case of S. aureus ATCC 9144, the best results were obtained using caprylic acid on its own. It was concluded that sophorolipids are promising compounds for the inhibition/disruption of biofilms formed by Gram-positive and Gram-negative microorganisms and this activity can be enhanced by the presence of booster compounds such as caprylic acid.
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Affiliation(s)
- Mayri A Díaz De Rienzo
- School of Chemical Engineering and Analytical Science, University of Manchester, Manchester, M13 9PL, UK
| | - Paul Stevenson
- Unilever Research and Development Laboratory, Port Sunlight, Wirral, CH62 4ZD, UK
| | - Roger Marchant
- School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA, Northern Ireland, UK
| | - Ibrahim M Banat
- School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA, Northern Ireland, UK
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28
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Synthesis and Properties of N-Alkyl–N,N-Dimethyl-N-(o-Hydroxymethyl)Benzylammonium Chlorides. J SURFACTANTS DETERG 2015. [DOI: 10.1007/s11743-015-1706-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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29
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Ismail W, Shammary SA, El-Sayed WS, Obuekwe C, El Nayal AM, Abdul Raheem AS, Al-Humam A. Stimulation of rhamnolipid biosurfactants production in Pseudomonas aeruginosa AK6U by organosulfur compounds provided as sulfur sources. ACTA ACUST UNITED AC 2015. [PMID: 28626715 PMCID: PMC5466058 DOI: 10.1016/j.btre.2015.03.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Organosulfur compounds promote biosurfactants production when provided as sulfur sources. Quantitative and qualitative changes in biosurfactants production depending on the sulfur source. Simultaneous production of biosurfactants and biodesulfurization.
A Pseudomonas aeruginosa AK6U strain produced rhamnolipid biosurfactants to variable extents when grown on MgSO4 or organosulfur compounds as sulfur sources and glucose as a carbon source. Organosulfur cultures produced much higher biosurfactants amounts compared to the MgSO4 cultures. The surface tension of the growth medium was reduced from 72 mN/m to 54 and 30 mN/m in cultures containing MgSO4 and 4,6-dimethyldibenzothiophene (4,6-DM-DBT), respectively. AK6U cultures produced different rhamnolipid congener profiles depending on the provided sulfur source. The dibenzothiophene (DBT) culture produced more diverse and a higher number of rhamnolipid congeners as compared to the DBT-sulfone and MgSO4 cultures. The number of mono-rhamnolipid congeners in the DBT culture was also higher than that detected in the DBT-sulfone and MgSO4 cultures. Di-rhamnolipids dominated the congener profiles in all the analyzed cultures. The sulfur source can have a profound impact on the quality and quantity of the produced biosurfactants.
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Affiliation(s)
- Wael Ismail
- Life Sciences Department, Biotechnology Program, College of Graduate Studies, Arabian Gulf University, Manama, Bahrain
| | - Sultanah Al Shammary
- Life Sciences Department, Biotechnology Program, College of Graduate Studies, Arabian Gulf University, Manama, Bahrain
| | - Wael S El-Sayed
- Taibah University, Faculty of Science, Biology Department, Al-Madinah Al-Munawarah, 344, Saudi Arabia
| | - Christian Obuekwe
- Department of Biological Sciences, College of Science, Kuwait University, Kuwait
| | - Ashraf M El Nayal
- Life Sciences Department, Biotechnology Program, College of Graduate Studies, Arabian Gulf University, Manama, Bahrain
| | - Abdul Salam Abdul Raheem
- Life Sciences Department, Biotechnology Program, College of Graduate Studies, Arabian Gulf University, Manama, Bahrain
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Madsen JK, Pihl R, Møller AH, Madsen AT, Otzen DE, Andersen KK. The anionic biosurfactant rhamnolipid does not denature industrial enzymes. Front Microbiol 2015; 6:292. [PMID: 25941516 PMCID: PMC4400916 DOI: 10.3389/fmicb.2015.00292] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 03/24/2015] [Indexed: 11/13/2022] Open
Abstract
Biosurfactants (BS) are surface-active molecules produced by microorganisms. Their combination of useful properties and sustainable production make them promising industrial alternatives to petrochemical and oleochemical surfactants. Here we compare the impact of the anionic BS rhamnolipid (RL) and the conventional/synthetic anionic surfactant sodium dodecyl sulfate (SDS) on the structure and stability of three different commercially used enzymes, namely the cellulase Carezyme® (CZ), the phospholipase Lecitase Ultra® (LT) and the α-amylase Stainzyme® (SZ). Our data reveal a fundamental difference in their mode of interaction. SDS shows great diversity of interaction toward the different enzymes. It efficiently unfolds both LT and CZ, but LT is unfolded by SDS through formation of SDS clusters on the enzyme well below the cmc, while CZ is only unfolded by bulk micelles and on average binds significantly less SDS than LT. SDS binds with even lower stoichiometry to SZ and leads to an increase in thermal stability. In contrast, RL does not affect the tertiary or secondary structure of any enzyme at room temperature, has little impact on thermal stability and only binds detectably (but at low stoichiometries) to SZ. Furthermore, all enzymes maintain activity at both monomeric and micellar concentrations of RL. We conclude that RL, despite its anionic charge, is a surfactant that does not compromise the structural integrity of industrially relevant enzymes. This makes RL a promising alternative to current synthetic anionic surfactants in a wide range of commercial applications.
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Affiliation(s)
| | | | | | | | - Daniel E. Otzen
- Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology and Genetics, Aarhus UniversityAarhus, Denmark
| | - Kell K. Andersen
- Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology and Genetics, Aarhus UniversityAarhus, Denmark
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Díaz De Rienzo MA, Banat IM, Dolman B, Winterburn J, Martin PJ. Sophorolipid biosurfactants: Possible uses as antibacterial and antibiofilm agent. N Biotechnol 2015; 32:720-6. [PMID: 25738966 DOI: 10.1016/j.nbt.2015.02.009] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 02/06/2015] [Accepted: 02/14/2015] [Indexed: 11/19/2022]
Abstract
Biosurfactants are amphipathic, surface-active molecules of microbial origin which accumulate at interfaces reducing interfacial tension and leading to the formation of aggregated micellular structures in solution. Some biosurfactants have been reported to have antimicrobial properties, the ability to prevent adhesion and to disrupt biofilm formation. We investigated antimicrobial properties and biofilm disruption using sophorolipids at different concentrations. Growth of Gram negative Cupriavidus necator ATCC 17699 and Gram positive Bacillus subtilis BBK006 were inhibited by sophorolipids at concentrations of 5% v/v with a bactericidal effect. Sophorolipids (5% v/v) were also able to disrupt biofilms formed by single and mixed cultures of B. subtilis BBK006 and Staphylococcus aureus ATCC 9144 under static and flow conditions, as was observed by scanning electron microscopy. The results indicated that sophorolipids may be promising compounds for use in biomedical application as adjuvants to other antimicrobial against some pathogens through inhibition of growth and/or biofilm disruption.
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Affiliation(s)
- Mayri A Díaz De Rienzo
- School of Chemical Engineering and Analytical Science, The University of Manchester, Manchester M13 9PL, UK.
| | - Ibrahim M Banat
- School of Biomedical Sciences, University of Ulster, Coleraine BT52 1SA, Northern Ireland, UK
| | - Ben Dolman
- School of Chemical Engineering and Analytical Science, The University of Manchester, Manchester M13 9PL, UK
| | - James Winterburn
- School of Chemical Engineering and Analytical Science, The University of Manchester, Manchester M13 9PL, UK
| | - Peter J Martin
- School of Chemical Engineering and Analytical Science, The University of Manchester, Manchester M13 9PL, UK
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32
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Dirhamnose-lipid production by recombinant nonpathogenic bacterium Pseudomonas chlororaphis. Appl Microbiol Biotechnol 2015; 99:4333-42. [PMID: 25661819 DOI: 10.1007/s00253-015-6433-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 01/21/2015] [Accepted: 01/23/2015] [Indexed: 10/24/2022]
Abstract
We previously discovered that Pseudomonas chlororaphis NRRL B-30761 produces monorhamnolipids (R1Ls) with predominantly 3-hydroxydodecenoyl-3-hydroxydecanoate (C12:1-C10) or 3-hydroxydodecanoyl-3-hydroxydecanoate (C12-C10) as the lipid moiety under static growth conditions only. We have now cloned, sequenced, and analyzed in silico the gene locus of NRRL B-30761 containing the putative coding sequences of rhamnosyltransferase chain A (rhlA Pch , 894 bps), rhamnosyltransferase chain B (rhlB Pch , 1272 bps), and N-acyl-homoserine lactone-dependent transcriptional regulatory protein (rhlR Pch , 726 bps). The putative gene products RhlAPch (297 amino acid residues or a.a.), RhlBPch (423 a.a.), and RhlRPch (241 a.a.) only have between 60 and 65% a.a. identities to their respective closest matched homologs in P. aeruginosa. Polymerase chain reaction (PCR)-based assay did not detect the presence of rhamnosyltransferase C gene (rhlC) in P. chlororaphis, suggesting a genetic basis for the lack of dirhamnose-lipid (R2L) synthesis in this organism. We thus genetically constructed an R2L-synthesizing P. chlororaphis by expressing a rhamnosyltransferase C (rhlC) gene of P. aeruginosa using an expression vector (pBS29-P2-gfp) containing a Pseudomonas syringae promoter. The R2L/R1L ratio is 2.4 in the rhamnolipid (RL) sample isolated from the genetically engineered (GE) P. chlororaphis [pBS29-P2-rhlC], in contrast to undetectable R2L in the GE P. chlororaphis [pBS29-P2-gfp] control cells based on LC-MS analysis. The critical micelle concentrations of the R2L and R1L samples from GE P. chlororaphis [pBS29-P2-rhlC] and the control [pBS29-P2-gfp] cells were ca. 0.1 mM, and their minimum surface tensions were ca. 26 mN/m with no significant difference.
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Fracchia L, J. Banat J, Cavallo M, Ceresa C, M. Banat I. Potential therapeutic applications of microbial surface-active compounds. AIMS BIOENGINEERING 2015. [DOI: 10.3934/bioeng.2015.3.144] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Andersen KK, Otzen DE. Denaturation of α-lactalbumin and myoglobin by the anionic biosurfactant rhamnolipid. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:2338-45. [DOI: 10.1016/j.bbapap.2014.10.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 09/30/2014] [Accepted: 10/07/2014] [Indexed: 11/26/2022]
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35
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Penfold J, Thomas RK. Neutron reflectivity and small angle neutron scattering: An introduction and perspective on recent progress. Curr Opin Colloid Interface Sci 2014. [DOI: 10.1016/j.cocis.2014.01.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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36
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37
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Micelle behaviors of sophorolipid/rhamnolipid binary mixed biosurfactant systems. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.06.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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38
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Hu D, Guo X, Jia L. Synthesis, Surface Active Properties of Novel Gemini Surfactants with Amide Groups and Rigid Spacers. J SURFACTANTS DETERG 2013. [DOI: 10.1007/s11743-013-1502-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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A comparison of effects of broad-spectrum antibiotics and biosurfactants on established bacterial biofilms. Curr Microbiol 2013; 67:614-23. [PMID: 23783562 DOI: 10.1007/s00284-013-0412-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 05/26/2013] [Indexed: 10/26/2022]
Abstract
Current antibiofilm solutions based on planktonic bacterial physiology have limited efficacy in clinical and occasionally environmental settings. This has prompted a search for suitable alternatives to conventional therapies. This study compares the inhibitory properties of two biological surfactants (rhamnolipids and a plant-derived surfactant) against a selection of broad-spectrum antibiotics (ampicillin, chloramphenicol and kanamycin). Testing was carried out on a range of bacterial physiologies from planktonic and mixed bacterial biofilms. Rhamnolipids (Rhs) have been extensively characterised for their role in the development of biofilms and inhibition of planktonic bacteria. However, there are limited direct comparisons with antimicrobial substances on established biofilms comprising single or mixed bacterial strains. Baseline measurements of inhibitory activity using planktonic bacterial assays established that broad-spectrum antibiotics were 500 times more effective at inhibiting bacterial growth than either Rhs or plant surfactants. Conversely, Rhs and plant biosurfactants reduced biofilm biomass of established single bacterial biofilms by 74-88 and 74-98 %, respectively. Only kanamycin showed activity against biofilms of Bacillus subtilis and Staphylococcus aureus. Broad-spectrum antibiotics were also ineffective against a complex biofilm of marine bacteria; however, Rhs and plant biosurfactants reduced biofilm biomass by 69 and 42 %, respectively. These data suggest that Rhs and plant-derived surfactants may have an important role in the inhibition of complex biofilms.
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Perfumo A, Rudden M, Smyth TJP, Marchant R, Stevenson PS, Parry NJ, Banat IM. Rhamnolipids are conserved biosurfactants molecules: implications for their biotechnological potential. Appl Microbiol Biotechnol 2013; 97:7297-306. [PMID: 23563913 DOI: 10.1007/s00253-013-4876-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 03/20/2013] [Accepted: 03/21/2013] [Indexed: 10/27/2022]
Abstract
A range of isolates of Pseudomonas aeruginosa from widely different environmental sources were examined for their ability to synthesise rhamnolipid biosurfactants. No significant differences in the quantity or composition of the rhamnolipid congeners could be produced by manipulating the growth conditions. Sequences for the rhamnolipid genes indicated low levels of strain variation, and the majority of polymorphisms did lead to amino acid sequence changes that had no evident phenotypic effect. Expression of the rhlB and rhlC rhamnosyltransferase genes showed a fixed sequential expression pattern during growth, and no significant up-regulation could be induced by varying producer strains or growth media. The results indicated that rhamnolipids are highly conserved molecules and that their gene expression has a rather stringent control. This leaves little opportunity to manipulate and greatly increase the yield of rhamnolipids from strains of P. aeruginosa for biotechnological applications.
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Affiliation(s)
- Amedea Perfumo
- School of Biomedical Sciences, University of Ulster, Coleraine BT52 1SA, UK
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Chen M, Dong C, Penfold J, Thomas RK, Smyth TJP, Perfumo A, Marchant R, Banat IM, Stevenson P, Parry A, Tucker I, Grillo I. Influence of calcium ions on rhamnolipid and rhamnolipid/anionic surfactant adsorption and self-assembly. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:3912-3923. [PMID: 23445348 DOI: 10.1021/la400432v] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The impact of Ca(2+) counterions on the adsorption at the air-water interface and self-assembly in aqueous solution of the rhamnolipid biosurfactant and its mixture with the anionic surfactant sodium dodecylbenzenesulfonate, LAS, has been studied using neutron reflectometry and small-angle neutron scattering. The results illustrate how rhamnolipids are calcium tolerant and how their blending with conventional anionic surfactants improves the calcium tolerance of the anionic surfactant. Ca(2+) has relatively little effect upon the adsorption and self-assembly of the monorhamnose, R1, and dirhamnose, R2, rhamnolipids, even at high pH, due to their predominantly nonionic nature. For R1/R2 mixtures the addition of Ca(2+) has little impact upon the adsorbed amount or the surface composition. For R2/LAS mixtures the addition of Ca(2+) results in an increased adsorption and a surface slightly richer in R2. The weak binding of Ca(2+) to R1 and R2 does result in a change to the degree of ionization of the micelles and especially for mixed R1/R2 micelles at R1-rich solution compositions. The stronger binding of Ca(2+) to LAS results in the addition of Ca(2+) having a much greater impact on the self-assembly of R1/LAS and R2/LAS mixtures. For R1/LAS mixtures the addition of Ca(2+) promotes the formation of more planar structures, even at low surfactant concentrations where in the absence of Ca(2+) mixed globular micelle formation dominates. In R2/LAS mixtures, where there is a greater contrast between the high and low preferred curvatures associated with R2 and LAS, the addition of Ca(2+) results in a more complex evolution in micellar aggregation and the degree of ionization of the micelles. This results in variations in Ca(2+) binding that promotes micellar structures in which a spatial segregation of the two surfactant components within the micelle occurs.
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Affiliation(s)
- Minglei Chen
- Physical and Theoretical Chemistry Laboratory, Oxford University, Oxford, UK
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Penfold J, Thomas RK. The limitations of models of surfactant mixing at interfaces as revealed by neutron scattering. Phys Chem Chem Phys 2013; 15:7017-27. [DOI: 10.1039/c3cp00104k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Marchant R, Banat IM. Microbial biosurfactants: challenges and opportunities for future exploitation. Trends Biotechnol 2012; 30:558-65. [DOI: 10.1016/j.tibtech.2012.07.003] [Citation(s) in RCA: 338] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 07/10/2012] [Accepted: 07/16/2012] [Indexed: 11/29/2022]
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Marchant R, Banat IM. Biosurfactants: a sustainable replacement for chemical surfactants? Biotechnol Lett 2012; 34:1597-605. [DOI: 10.1007/s10529-012-0956-x] [Citation(s) in RCA: 297] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 05/04/2012] [Indexed: 11/30/2022]
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Chen M, Dong C, Penfold J, Thomas RK, Smyth TJP, Perfumo A, Marchant R, Banat IM, Stevenson P, Parry A, Tucker I, Campbell RA. Adsorption of sophorolipid biosurfactants on their own and mixed with sodium dodecyl benzene sulfonate, at the air/water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:8854-8866. [PMID: 21657229 DOI: 10.1021/la201660n] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The adsorption of the lactonic (LS) and acidic (AS) forms of sophorolipid and their mixtures with the anionic surfactant sodium dodecyl benzene sulfonate (LAS) has been measured at the air/water interface by neutron reflectivity, NR. The AS and LS sophorolipids adsorb with Langmuir-like adsorption isotherms. The more hydrophobic LS is more surface active than the AS, with a lower critical micellar concentration, CMC, and stronger surface adsorption, with an area/molecule ∼70 Å(2) compared with 85 Å(2) for the AS. The acidic sophorolipid shows a maximum in its adsorption at the CMC which appears to be associated with a mixture of different isomeric forms. The binary LS/AS and LS/LAS mixtures show a strong surface partitioning in favor of the more surface active and hydrophobic LS component but are nevertheless consistent with ideal mixing at the interface. In contrast, the surface composition of the AS/LAS mixture is much closer to the solution composition, but the surface mixing is nonideal and can be accounted for by regular solution theory, RST. In the AS/LS/LAS ternary mixtures, the surface adsorption is dominated by the sophorolipid, and especially the LS component, in a way that is not consistent with the observations for the binary mixtures. The extreme partitioning in favor of the sophorolipid for the LAS/LS/AS (1:2) mixtures is attributed to a reduction in the packing constraints at the surface due to the AS component. Measurements of the surface structure reveal a compact monolayer for LS and a narrow solvent region for LS, LS/AS, and LS/LAS mixtures, consistent with the more hydrophobic nature of the LS component. The results highlight the importance of the relative packing constraints on the adsorption of multicomponent mixtures, and the impact of the lactonic form of the sophorolipid on the adsorption of the sophorolipid/LAS mixtures.
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Affiliation(s)
- Minglei Chen
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, United Kingdom
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Penfold J, Chen M, Thomas RK, Dong C, Smyth TJP, Perfumo A, Marchant R, Banat IM, Stevenson P, Parry A, Tucker I, Grillo I. Solution self-assembly of the sophorolipid biosurfactant and its mixture with anionic surfactant sodium dodecyl benzene sulfonate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:8867-8877. [PMID: 21644533 DOI: 10.1021/la201661y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The self-assembly in aqueous solution of the acidic (AS) and lactonic (LS) forms of the sophorolipid biosurfactant, their mixtures, and their mixtures with anionic surfactant sodium dodecyl benzene sulfonate, LAS, has been studied using predominantly small-angle neutron scattering, SANS, at relatively low surfactant concentrations of <30 mM. The more hydrophobic lactonic sophorolipid forms small unilamellar vesicles at low surfactant concentrations, in the concentration range of 0.2 to 3 mM, and transforms via a larger unilamellar vesicle structure at 7 mM to a disordered dilute phase of tubules at higher concentrations, 10 to 30 mM. In marked contrast, the acidic sophorolipid is predominantly in the form of small globular micelles in the concentration range of 0.5 to 30 mM, with a lower concentration of larger, more planar aggregates (lamellar or vesicular) in coexistence. In mixtures of AS and LS, over the same concentration range, the micellar structure associated with the AS sophorolipid dominates the mixed-phase behavior. In mixtures of anionic surfactant LAS with the AS sophorolipid, the globular micellar structure dominates over the entire composition and concentration range studied. In contrast, mixtures of LAS with the LS sophorolipid exhibit a rich evolution in phase behavior with solution composition and concentration. At low surfactant concentrations, the small unilamellar vesicle structure present for LS-rich solution compositions evolves into a globular micelle structure as the solution becomes richer in LAS. At higher surfactant concentrations, the disordered lamellar structure present for LS-rich compositions transforms to small vesicle/lamellar coexistence, to lamellar/micellar coexistence, to micellar/lamellar coexistence, and ultimately to a pure micellar phase as the solution becomes richer in LAS. The AS sophorolipid surfactant exhibits self-assembly properties similar to those of most other weakly ionic or nonionic surfactants that have relatively large headgroups. However, the more hydrophobic nature of the lactonic sophorolipid results in a more complex and unusual evolution in phase behavior with concentration and with concentration and composition when mixed with anionic surfactant LAS.
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Affiliation(s)
- Jeff Penfold
- Physical and Theoretical Chemistry Department, University of Oxford, Oxford, UK.
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