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New Frontiers Regarding Surfactants and Biosurfactants: Production, Characterization and Application

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Green Chemistry".

Deadline for manuscript submissions: closed (31 August 2021) | Viewed by 35834

Special Issue Editors


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Guest Editor
Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland
Interests: environmental microbiology; biodegradation of hydrocarbons, (bio)surfactants, herbicides and pharmaceuticals in aqueous and terrestrial environments; mechanisms of microbial adaptation to xenobiotics; environmental impact of ionic liquids
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Guest Editor
Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland
Interests: environmental impact of organic compounds; biodegradation of emulsified systems; treatment of industrial pollutants; production and application of biosurfactants
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Regional University Center of Excellence in Environmental Industry, Szent István University, Páter K. u. 1., 2100 Gödöllö, Hungary
Interests: microbial degradation of petroleum hydrocarbons; microbial ecology of microaerobic BTEX-degradation; taxonomy of xenobiotic-degrading bacteria; stable isotope probing and “omics” technologies

Special Issue Information

Dear Colleagues,

Surfactants are among the most commonly used groups of chemicals. Their applications range elements used in everyday life to specific applications in various industrial sectors. Since numerous representatives of surfactants exhibit potent biological activity, their presence in the environment is associated with notable hazards. As a result, an increasing interest in surface active compounds of biological origin has been observed over the last three decades. Biosurfactants have gained significant popularity as an environmentally friendly alternative to their synthetic counterparts in fields such as medicine, pharmaceutical production, oil recovery enhancement, and bioremediation. Consequently, the number of reports dedicated to the identification of biosurfactants originating from plants and microorganisms is steadily increasing. However, despite much promise, this approach has numerous limitations, most notably in terms of efficient production and purification. Considering the potential “pros” and “cons” of recent advances in the field of surface active compounds, the discussion regarding the displacement of synthetic surfactants with biosurfactants remains open.

This Special Issue of Molecules will focus on novel trends associated with the production, characterization, and application of synthetic and biological surfactants. We aim to provide a solid foundation for evaluating the feasibility of replacing conventional surfactants with biosurfactants.

Dr. Łukasz Chrzanowski
Dr. Łukasz Ławniczak
Dr. András Táncsics
Guest Editors

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Keywords

  • bioconversion of waste
  • bioremediation
  • biosurfactants
  • emulsification
  • MEOR
  • solubilization
  • surfactants
  • toxicity

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Published Papers (9 papers)

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Research

13 pages, 2083 KiB  
Article
Green Fabrication of Zinc Oxide Nanoparticles Using Phlomis Leaf Extract: Characterization and In Vitro Evaluation of Cytotoxicity and Antibacterial Properties
by Amal A. Alyamani, Salim Albukhaty, Salman Aloufi, Faizah A. AlMalki, Hassan Al-Karagoly and Ghassan M. Sulaiman
Molecules 2021, 26(20), 6140; https://doi.org/10.3390/molecules26206140 - 11 Oct 2021
Cited by 86 | Viewed by 5469
Abstract
Green nanoparticle synthesis is an environmentally friendly approach that uses natural solvents. It is preferred over chemical and physical techniques due to the time and energy savings. This study aimed to synthesize zinc oxide nanoparticles (ZnO NPs) through a green method that used [...] Read more.
Green nanoparticle synthesis is an environmentally friendly approach that uses natural solvents. It is preferred over chemical and physical techniques due to the time and energy savings. This study aimed to synthesize zinc oxide nanoparticles (ZnO NPs) through a green method that used Phlomis leaf extract as an effective reducing agent. The synthesis and characterization of ZnO NPs were confirmed by UV-Vis spectrophotometry, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic light scattering (DLS), Zeta potential, and Field Emission Scanning Electron Microscope (FESEM) techniques. In vitro cytotoxicity was determined in L929 normal fibroblast cells using MTT assay. The antibacterial activity of ZnO nanoparticles was investigated using a disk-diffusion method against S. aureus and E. coli, as well as minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) content concentrations. XRD results confirmed the nanoparticles’ crystalline structure. Nanoparticle sizes were found to be around 79 nm by FESEM, whereas the hydrodynamic radius of nanoparticles was estimated to be around 165 ± 3 nm by DLS. FTIR spectra revealed the formation of ZnO bonding and surfactant molecule adsorption on the surface of ZnO NPs. It is interesting to observe that aqueous extracts of Phlomis leave plant are efficient reducing agents for green synthesis of ZnO NPs in vitro, with no cytotoxic effect on L929 normal cells and a significant impact on the bacteria tested. Full article
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18 pages, 2552 KiB  
Article
Transformation of Iodosulfuron-Methyl into Ionic Liquids Enables Elimination of Additional Surfactants in Commercial Formulations of Sulfonylureas
by Witold Stachowiak, Radosław Szumski, Jan Homa, Marta Woźniak-Karczewska, Anna Parus, Beata Strzemiecka, Łukasz Chrzanowski and Michał Niemczak
Molecules 2021, 26(15), 4396; https://doi.org/10.3390/molecules26154396 - 21 Jul 2021
Cited by 13 | Viewed by 2757
Abstract
Efficient use of herbicides for plant protection requires the application of auxiliary substances such as surfactants, stabilizers, wetting or anti-foaming agents, and absorption enhancers, which can be more problematic for environment than the herbicides themselves. We hypothesized that the combination of sulfonylurea (iodosulfuron-methyl) [...] Read more.
Efficient use of herbicides for plant protection requires the application of auxiliary substances such as surfactants, stabilizers, wetting or anti-foaming agents, and absorption enhancers, which can be more problematic for environment than the herbicides themselves. We hypothesized that the combination of sulfonylurea (iodosulfuron-methyl) anion with inexpensive, commercially available quaternary tetraalkylammonium cations could lead to biologically active ionic liquids (ILs) that could become a convenient and environment-friendly alternative to adjuvants. A simple one-step synthesis allowed for synthesizing iodosulfuron-methyl based ILs with high yields ranging from 88 to 96% as confirmed by UV, FTIR, and NMR. The obtained ILs were found to possess several favorable properties compared to the currently used sodium salt iodosulfuron-methyl, such as adjustable hydrophobicity (octanol-water partition coefficient) and enhanced stability in aqueous solutions, which was supported by molecular calculations showing cation–anion interaction energies. In addition, soil mobility and volatility of ILs were more beneficial compared to the parental herbicide. Herbicidal activity tests toward oil-seed rape and cornflower revealed that ILs comprising at least one alkyl chain in the decyl to octadecyl range had similar or better efficacy compared to the commercial preparation without addition of any adjuvant. Furthermore, results of antimicrobial activity indicated that they were practically harmless or slightly toxic toward model soil microorganisms such as Pseudomonas putida and Bacillus cereus. Full article
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17 pages, 4179 KiB  
Article
Influence of the Medium Composition and the Culture Conditions on Surfactin Biosynthesis by a Native Bacillus subtilis natto BS19 Strain
by Beata Koim-Puchowska, Grzegorz Kłosowski, Joanna Maria Dróżdż-Afelt, Dawid Mikulski and Alicja Zielińska
Molecules 2021, 26(10), 2985; https://doi.org/10.3390/molecules26102985 - 18 May 2021
Cited by 11 | Viewed by 4649
Abstract
An effective microbial synthesis of surfactin depends on the composition of the culture medium, the culture conditions and the genetic potential of the producer strain. The aim of this study was to evaluate the suitability of various medium components for the surfactin producing [...] Read more.
An effective microbial synthesis of surfactin depends on the composition of the culture medium, the culture conditions and the genetic potential of the producer strain. The aim of this study was to evaluate the suitability of various medium components for the surfactin producing strain and to determine the impact of the culture conditions on the biosynthesis of surfactin isoforms by the newly isolated native strain Bacillus subtilis natto BS19. The efficiency of surfactin biosynthesis was determined by measuring the surface tension of the medium before and after submerged culture (SmF) and by qualitative and quantitative analysis of the obtained compound by high performance liquid chromatography. The highest efficiency of surfactin biosynthesis was achieved using starch as the carbon source and yeast extract as the nitrogen source at pH 7.0 and 37 °C. Potato peelings were selected as an effective waste substrate. It was shown that the increase in the percentage of peel extract in the culture medium enhanced the biosynthesis of surfactin (mg/L) (2–30.9%; 4–46.0% and 6–58.2%), while reducing surface tension of the medium by about 50%. The obtained results constitute a promising basis for further research on biosynthesis of surfactin using potato peelings as a cheap alternative to synthetic medium components. Full article
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16 pages, 1366 KiB  
Article
Microwave-Assisted One-Pot Lipid Extraction and Glycolipid Production from Oleaginous Yeast Saitozyma podzolica in Sugar Alcohol-Based Media
by André Delavault, Katarina Ochs, Olga Gorte, Christoph Syldatk, Erwann Durand and Katrin Ochsenreither
Molecules 2021, 26(2), 470; https://doi.org/10.3390/molecules26020470 - 18 Jan 2021
Cited by 14 | Viewed by 4551
Abstract
Glycolipids are non-ionic surfactants occurring in numerous products of daily life. Due to their surface-activity, emulsifying properties, and foaming abilities, they can be applied in food, cosmetics, and pharmaceuticals. Enzymatic synthesis of glycolipids based on carbohydrates and free fatty acids or esters is [...] Read more.
Glycolipids are non-ionic surfactants occurring in numerous products of daily life. Due to their surface-activity, emulsifying properties, and foaming abilities, they can be applied in food, cosmetics, and pharmaceuticals. Enzymatic synthesis of glycolipids based on carbohydrates and free fatty acids or esters is often catalyzed using certain acyltransferases in reaction media of low water activity, e.g., organic solvents or notably Deep Eutectic Systems (DESs). Existing reports describing integrated processes for glycolipid production from renewables use many reaction steps, therefore this study aims at simplifying the procedure. By using microwave dielectric heating, DESs preparation was first accelerated considerably. A comparative study revealed a preparation time on average 16-fold faster than the conventional heating method in an incubator. Furthermore, lipids from robust oleaginous yeast biomass were successfully extracted up to 70% without using the pre-treatment method for cell disruption, limiting logically the energy input necessary for such process. Acidified DESs consisting of either xylitol or sorbitol and choline chloride mediated the one-pot process, allowing subsequent conversion of the lipids into mono-acylated palmitate, oleate, linoleate, and stearate sugar alcohol esters. Thus, we show strong evidence that addition of immobilized Candida antarctica Lipase B (Novozym 435®), in acidified DES mixture, enables a simplified and fast glycolipid synthesis using directly oleaginous yeast biomass. Full article
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20 pages, 3091 KiB  
Article
Evaluation of Clay Hydration and Swelling Inhibition Using Quaternary Ammonium Dicationic Surfactant with Phenyl Linker
by Mobeen Murtaza, Hafiz Mudaser Ahmad, Muhammad Shahzad Kamal, Syed Muhammad Shakil Hussain, Mohamed Mahmoud and Shirish Patil
Molecules 2020, 25(18), 4333; https://doi.org/10.3390/molecules25184333 - 22 Sep 2020
Cited by 27 | Viewed by 4500
Abstract
Water-based drilling fluids are extensively used for drilling oil and gas wells. However, water-based muds cause clay swelling, which severely affects the stability of wellbore. Due to two adsorption positions, it is expected that cationic gemini surfactants can reduce the clay swelling. In [...] Read more.
Water-based drilling fluids are extensively used for drilling oil and gas wells. However, water-based muds cause clay swelling, which severely affects the stability of wellbore. Due to two adsorption positions, it is expected that cationic gemini surfactants can reduce the clay swelling. In this work, quaternary ammonium dicationic gemini surfactants containing phenyl linkers and different counterions (Cl and Br) were synthesized, and the effect of variation in counterions on swelling and hydration properties of shales was studied. Numerous water-based drilling fluid formulations were prepared with different concentrations of surfactants to study the swelling inhibition capacity of surfactants. The performance of surfactant-containing drilling muds was evaluated by comparing them with base drilling mud, and sodium silicate drilling mud. Various experimental techniques were employed to study drilling mud characteristics such as rheology and filtration. The inhibition properties of drilling mud formulations were determined by linear swelling experiment, capillary suction time test, particle size distribution measurement, wettability measurements, and X-ray Diffraction (XRD). Experimental results showed that surfactant-based formulation containing bromide counterion exhibited superior rheological properties as compared to other investigated formulations. The filtration test showed that the gemini surfactant with chloride counterion had higher filtrate loss compared to all other formulations. The bentonite swelling was significantly reduced with increasing the concentration of dicationic surfactants as inhibitors, and maximum reduction in the linear swelling rate was observed by using a formulation containing surfactant with chloride counterion. The lowest capillary suction timer (CST) was obtained in the formulation containing surfactant with chloride counterion as less CST indicated the enhanced inhibition capacity. The particle size measurement showed that average bentonite particle size increased upon the addition of surfactants depicting the inhibition capacity. The increase in basal spacing obtained from XRD analysis showed the intercalation of gemini surfactants in interlayers of bentonite. The contact angle measurements were performed to study the wettability of the bentonite film surface, and the results showed that hydrophobicity increased by incorporating the surfactants to the drilling fluid. Full article
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15 pages, 2061 KiB  
Article
Synergistic Solubilization of Phenanthrene by Mixed Micelles Composed of Biosurfactants and a Conventional Non-Ionic Surfactant
by Jianfei Liu, Yuru Wang and Huifang Li
Molecules 2020, 25(18), 4327; https://doi.org/10.3390/molecules25184327 - 21 Sep 2020
Cited by 19 | Viewed by 3021
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 [...] Read more.
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. Full article
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20 pages, 6918 KiB  
Article
Interfacial and Foaming Properties of Tailor-Made Glycolipids—Influence of the Hydrophilic Head Group and Functional Groups in the Hydrophobic Tail
by Rebecca Hollenbach, Annika Ricarda Völp, Ludwig Höfert, Jens Rudat, Katrin Ochsenreither, Norbert Willenbacher and Christoph Syldatk
Molecules 2020, 25(17), 3797; https://doi.org/10.3390/molecules25173797 - 20 Aug 2020
Cited by 12 | Viewed by 3709
Abstract
Glycolipids are a class of biodegradable surfactants less harmful to the environment than petrochemically derived surfactants. Here we discuss interfacial properties, foam stability, characterized in terms of transient foam height, gas volume fraction and bubble diameter as well as texture of seven enzymatically [...] Read more.
Glycolipids are a class of biodegradable surfactants less harmful to the environment than petrochemically derived surfactants. Here we discuss interfacial properties, foam stability, characterized in terms of transient foam height, gas volume fraction and bubble diameter as well as texture of seven enzymatically synthesized surfactants for the first time. Glycolipids consisting of different head groups, namely glucose, sorbitol, glucuronic acid and sorbose, combined with different C10 acyl chains, namely decanoate, dec-9-enoate and 4-methyl-nonanoate are compared. Equilibrium interfacial tension values vary between 24.3 and 29.6 mN/m, critical micelle concentration varies between 0.7 and 3.0 mM. In both cases highest values were found for the surfactants with unsaturated or branched tail groups. Interfacial elasticity and viscosity, however, were significantly reduced in these cases. Head and tail group both affect foam stability. Foams from glycolipids with sorbose and glucuronic acid derived head groups showed higher stability than those from surfactants with glucose head group, sorbitol provided lowest foam stability. We attribute this to different head group hydration also showing up in the time to reach equilibrium interfacial adsorption. Unsaturated tail groups reduced whereas branching enhanced foam stability compared to the systems with linear, saturated tail. Moreover, the tail group strongly influences foam texture. Glycolipids with unsaturated tail groups produced foams quickly collapsing even at smallest shear loads, whereas the branched tail group yielded a higher modulus than the linear tails. Normalized shear moduli for the systems with different head groups varied in a narrow range, with the highest value found for decylglucuronate. Full article
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14 pages, 2236 KiB  
Article
Novel Treatment for Mitigating Condensate Bank Using a Newly Synthesized Gemini Surfactant
by Amjed Hassan, Mohamed Mahmoud, Muhammad Shahzad Kamal, Syed Muhammad Shakil Hussain and Shirish Patil
Molecules 2020, 25(13), 3030; https://doi.org/10.3390/molecules25133030 - 2 Jul 2020
Cited by 7 | Viewed by 2646
Abstract
Condensate accumulation in the vicinity of the gas well is known to curtail hydrocarbon production by up to 80%. Numerous approaches are being employed to mitigate condensate damage and improve gas productivity. Chemical treatment, gas recycling, and hydraulic fracturing are the most effective [...] Read more.
Condensate accumulation in the vicinity of the gas well is known to curtail hydrocarbon production by up to 80%. Numerous approaches are being employed to mitigate condensate damage and improve gas productivity. Chemical treatment, gas recycling, and hydraulic fracturing are the most effective techniques for combatting the condensate bank. However, the gas injection technique showed temporary condensate recovery and limited improvement in gas productivity. Hydraulic fracturing is considered to be an expensive approach for treating condensate banking problems. In this study, a newly synthesized gemini surfactant (GS) was developed to prevent the formation of condensate blockage in the gas condensate reservoirs. Flushing the near-wellbore area with GS will change the rock wettability and thereby reduce the capillary forces holding the condensate due to the strong adsorption capacity of GS on the rock surface. In this study, several measurements were conducted to assess the performance of GS in mitigating the condensate bank including coreflood, relative permeability, phase behavior, and nuclear magnetic resonance (NMR) measurements. The results show that GS can reduce the capillary pressure by as much as 40%, increase the condensate mobility by more than 80%, and thereby mitigate the condensate bank by up to 84%. Phase behavior measurements indicate that adding GS to the oil–brine system could not induce any emulsions at different salinity levels. Moreover, NMR and permeability measurements reveal that the gemini surfactant has no effect on the pore system and no changes were observed in the T2 relaxation profiles with and without the GS injection. Ultimately, this work introduces a novel and effective treatment for mitigating the condensate bank. The new treatment showed an attractive performance in reducing liquid saturation and increasing the condensate relative permeability. Full article
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19 pages, 3404 KiB  
Article
Enhancement of A Cationic Surfactant by Capping Nanoparticles: Synthesis, Characterization and Multiple Applications
by A. Labena, M. A. Hegazy, W. M. Kamel, Amr Elkelish and Wael N. Hozzein
Molecules 2020, 25(9), 2007; https://doi.org/10.3390/molecules25092007 - 25 Apr 2020
Cited by 15 | Viewed by 3363
Abstract
There is scarce information on cationic surfactants’ biocidal and corrosion inhbibition effects on Slime-Forming Bacteria (SFB) isolated from oil field formation water. Therefore, this work focused on the the synthesis of a cationic surfactant (CS) to increase its features by capping different metal [...] Read more.
There is scarce information on cationic surfactants’ biocidal and corrosion inhbibition effects on Slime-Forming Bacteria (SFB) isolated from oil field formation water. Therefore, this work focused on the the synthesis of a cationic surfactant (CS) to increase its features by capping different metal nanoparticles (zinc, ZnNPs-C-CS; manganese, MnNPs-C-CS and tin, SnNPs-C-CS) and used them as biocides and corrosion inhibitors. The cationic surfactant was synthesized and characterized by Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. Afterwards, different nanoparticles were synthesized, characterized, and exploited to cap by the CS. The CS and the different nanoparticles capped by the CS were tested for their antimicrobial susceptibility against standard bacterial and yeast strains. The synthesized compounds were further evaluated as anti-biofilms agents against positively-developed bacterial biofilms. Moreover, the CS and the ZnNPs-C-CS, MnNPs-C-CS, and SnNPs-C-CS were assessed as potential biocides against SFB, particularly Pseudomonas sp. (isolated from contaminated formation water), and as corrosion inhibitors against cultivated salinity. The results revealed the great effect of the different CS-capped NPs as broad-spectrum antimicrobial and anti-biofilm agents at lower Minimum Inhibitory Concentrations (MICs), Minimum Bactericidal Concentrations (MBCs), Minimum Fungicidal Concentrations (MFCs) and Minimum Biofilm Inhibitory Concentrations (MBICs), and the activities were reported in order of SnNPs-C-CS > MnNPs-C-CS > ZnNPs-C-CS > CS. Furthermore, the ZnNPs-C-CS, MnNPs-C-CS, and SnNPs-C-CS demonstrated biocidal and corrosion inhibition effects against Pseudomonas sp. at a salinity of 3.5% NaCl, with metal corrosion inhibition efficiencies of 88.6, 94.0 and 96.9%, in comparison to a CS efficiency of 85.7%. In conclusion, the present work provides a newly synthesized cationic surfactant and has enhanced its antimicrobial and its metal corrosion inhibition effects by capping different nanoparticles, and it has been successfully applied against slime-forming bacteria at a salinity of 3.5% NaCl. Full article
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