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Bioremediation of an agricultural saline soil contaminated with endosulfan and Escherichia coli by an active surface agent induced in a Penicillium crustosum culture.
Landa-Faz, A, Rodríguez-Vázquez, R, Roldán-Carrillo, TG, Hidalgo-Lara, ME, Aguilar-López, R, Cebrián-García, ME
Preparative biochemistry & biotechnology. 2022;(3):292-301
Abstract
This study evaluates the production of a biological active surface agent (BASA) through its surface tension (ST) and emulsifying activity (E24) for endosulfan degradation (ED) and Escherichia coli growth inhibition (EcGI) in an agricultural saline soil. The fungus, identified as Penicillium crustosum was isolated from the Citrus sinensis peel (CsP), then the surface properties were evaluated in 9 culture media through a Taguchi L9 experimental design. The culture conditions included: stirring speed, pH, carbon (C) and nitrogen (N) sources; being glucose, NH4N03, 120 rpm and pH of 5, the most significant parameters in the BASA production. The BASA identified as a lipopeptide type, showed a ST = 38 mN m-1 and E24=71%. Both properties were stable at 80 °C, while ST presented stability in the pH range of 2 - 12, and a saline concentration of 200 g L-1; E24 was also stable at a pH between 8-12. Further application of BASA and fungal inoculum to a contaminated agricultural saline soil presented an EcGI of 99.8% on the 8th day, and ED of 92.9 ± 4.7% in 30 days, respectively; being the first report that uses this fungus for pesticide and bacteria elimination from an agricultural saline soil.
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2.
General characteristics of the influence of surfactants on the bacteriolytic activity of lysozyme based on the example of enzymatic lysis of Lactobacillus plantarum cells in the presence of Tween 21 and SDS.
Lu, WJ, Smirnov, SA, Levashov, PA
Biochemical and biophysical research communications. 2021;:73-77
Abstract
The general characteristics of the effect of surfactants on the activity of lysozyme were demonstrated. The kinetics of bacterial cell lysis is consistent with the Michaelis-Menten equation and the presence of surfactants does not shift the pH-optimum of activity. Surfactants do not change the Km value but instead, affect the Vmax value. The experimental dependencies are well described by theoretical equations, which assume three surfactant binding sites on the lysozyme molecule. The dependencies of the activity of lysozyme on the surfactant concentration are either a step type (i.e., a higher plateau becomes a lower plateau), or a dependency with a maximum and continuation of the curve in the form of a plateau but with an increase in the surfactant concentration. It can be assumed that there is a mechanism for the regulation of lysozyme activity by an unknown natural factor that has a suitable hydrophobic radical capable of binding to the surface of lysozyme.
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3.
Bile acid sequestrants: a review of mechanism and design.
Feng, Y, Li, Q, Ou, G, Yang, M, Du, L
The Journal of pharmacy and pharmacology. 2021;(7):855-861
Abstract
OBJECTIVE Bile acid sequestrants (BAS) are used extensively in the treatment of hypercholesterolaemia. This brief review aimed to describe the design and evaluation of three types of BAS: amphiphilic copolymers, cyclodextrin/poly-cyclodextrin and molecular imprinted polymers. The mechanisms underlying the action of BAS are also discussed. KEY FINDINGS BAS could lower plasma cholesterol, improve glycemic control in patients with type 2 diabetes and regulate balance energy metabolism via receptors or receptor-independent mediated mechanisms. Different types of BAS have different levels of ability to bind to bile acids, different stability and different in-vivo activity. CONCLUSIONS A growing amount of evidence suggests that bile acids play important roles not only in lipid metabolism but also in glucose metabolism. The higher selectivity, specificity, stability and in-vivo activity of BAS show considerable potential for lipid-lowering therapy.
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4.
Intestinal permeation enhancers: Lessons learned from studies using an organ culture model.
Danielsen, EM
Biochimica et biophysica acta. Biomembranes. 2021;(1):183474
Abstract
Permeation enhancers (PEs) are compounds aimed to increase intestinal uptake of oral drugs with poor bioavailability. This mini-review focuses on results recently obtained with PEs using an intestinal organ culture model. The model predicts which paracellular/transcellular pathways across the epithelium are susceptible to different classes of PEs (mainly surfactants and cell penetrating peptides). PEs: 1) generate a transmembrane transcellular pathway, 2) block apical endocytosis (first step in apical-to-basolateral transcytosis), and 3) perturb normal cell membrane integrity. The results argue that surfactants and cell penetrating peptides are not suitable for use in formulations aimed to exploit transcytosis in oral drug delivery.
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5.
Whey Proteins as a Potential Co-Surfactant with Aesculus hippocastanum L. as a Stabilizer in Nanoemulsions Derived from Hempseed Oil.
Smułek, W, Siejak, P, Fathordoobady, F, Masewicz, Ł, Guo, Y, Jarzębska, M, Kitts, DD, Kowalczewski, PŁ, Baranowska, HM, Stangierski, J, et al
Molecules (Basel, Switzerland). 2021;(19)
Abstract
The use of natural surfactants including plant extracts, plant hydrocolloids and proteins in nanoemulsion systems has received commercial interest due to demonstrated safety of use and potential health benefits of plant products. In this study, a whey protein isolate (WPI) from a byproduct of cheese production was used to stabilize a nanoemulsion formulation that contained hempseed oil and the Aesculus hippocastanum L. extract (AHE). A Box-Behnken experimental design was used to set the formulation criteria and the optimal nanoemulsion conditions, used subsequently in follow-up experiments that measured specifically emulsion droplet size distribution, stability tests and visual quality. Regression analysis showed that the concentration of HSO and the interaction between HSO and the WPI were the most significant factors affecting the emulsion polydispersity index and droplet size (nm) (p < 0.05). Rheological tests, Fourier transform infrared spectroscopy (FTIR) analysis and L*a*b* color parameters were also taken to characterize the physicochemical properties of the emulsions. Emulsion systems with a higher concentration of the AHE had a potential metabolic activity up to 84% in a microbiological assay. It can be concluded from our results that the nanoemulsion system described herein is a safe and stable formulation with potential biological activity and health benefits that complement its use in the food industry.
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6.
Computational and Experimental Models of Type III Lipid-Based Formulations of Loratadine Containing Complex Nonionic Surfactants.
Guruge, AG, Warren, DB, Benameur, H, Ford, L, Williams, HD, Jannin, V, Pouton, CW, Chalmers, DK
Molecular pharmaceutics. 2021;(12):4354-4370
Abstract
Type III lipid-based formulations (LBFs) combine poorly water-soluble drugs with oils, surfactants, and cosolvents to deliver the drugs into the systemic circulation. However, the solubility of the drug can be influenced by the colloidal phases formed in the gastrointestinal tract as the formulation is dispersed and makes contact with bile and other materials present within the GI tract. Thus, an understanding of the phase behavior of LBFs in the gut is critical for designing efficient LBFs. Molecular dynamics (MD) simulation is a powerful tool for the study of colloidal systems. In this study, we modeled the internal structures of five type III LBFs of loratadine containing poly(ethylene oxide) nonionic surfactants polysorbate 80 and polyoxyl hydrogenated castor oil (Kolliphor RH40) using long-timescale MD simulations (0.4-1.7 μs). We also conducted experimental investigations (dilution of formulations with water) including commercial Claritin liquid softgel capsules. The simulations show that LBFs form continuous phase, water-swollen reverse micelles, and bicontinuous and phase-separated systems at different dilutions, which correlate with the experimental observations. This study supports the use of MD simulation as a predictive tool to determine the fate of LBFs composed of medium-chain lipids, polyethylene oxide surfactants, and polymers.
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7.
Emulsification of Surfactant on Oil Droplets by Molecular Dynamics Simulation.
Cheng, Y, Yuan, S
Molecules (Basel, Switzerland). 2020;(13)
Abstract
Heavy oil in crude oil flooding is extremely difficult to extract due to its high viscosity and poor fluidity. In this paper, molecular dynamics simulation was used to study the emulsification behavior of sodium dodecyl sulfonate (SDSn) micelles on heavy oil droplets composed of asphaltenes (ASP) at the molecular level. Some analyzed techniques were used including root mean square displacement, hydrophile-hydrophobic area of an oil droplet, potential of mean force, and the number of hydrogen bonds between oil droplet and water phase. The simulated results showed that the asphaltene with carboxylate groups significantly enhances the hydration layer on the surface of oil droplets, and SDSn molecules can change the strength of the hydration layer around the surface of the oil droplets. The water bridge structure between both polar heads of the surfactant was commonly formed around the hydration layer of the emulsified oil droplet. During the emulsification of heavy oil, the ratio of hydrophilic hydrophobic surface area around an oil droplet is essential. Molecular dynamics method can be considered as a helpful tool for experimental techniques at the molecular level.
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8.
Biotechnological Applications of Paenibacillus sp. D9 Lipopeptide Biosurfactant Produced in Low-cost Substrates.
Jimoh, AA, Lin, J
Applied biochemistry and biotechnology. 2020;(3):921-941
Abstract
The present study assesses the Paenibacillus sp. D9 lipopeptide biosurfactant synthesis in cheap substrates including functional properties and applicability for varying biotechnological processes. Different experimental setups were made for oil dispersion, heavy metals removals from contaminated environments, and washing performance. The study revealed surface tension activities of 31.7-32.7 mN/m, and maximum biosurfactant yield of more than 8 g/L. Removals of 85.90%, 98.68%, 99.97%, 63.28%, 99.93%, and 94.22% were obtained for Ca, Cu, Fe, Mg, Ni, and Zn, respectively from acid mine effluents. In comparison with chemical surfactants, there was pronounced removal of heavy metals from wastewater, contaminated sands, and vegetable matter, as well as improved oil dispersing activity. A comparative study revealed that biosurfactant was more efficient (> 60%) for removal of tomato sauce and coffee stains than chemical surfactants (< 50%). Thus, lipopeptide biosurfactants are green biomolecules reducing hazards and contaminations within the environment. The future use of this lipopeptide biosurfactant is greatly promising in biotechnology.
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9.
Gas Crosstalk between PFPE-PEG-PFPE Triblock Copolymer Surfactant-Based Microdroplets and Monitoring Bacterial Gas Metabolism with Droplet-Based Microfluidics.
Ki, S, Kang, DK
Biosensors. 2020;(11)
Abstract
The PFPE-PEG-PFPE (Perfluoropolyether-polyethylene glycol-perfluoropolyether) surfactant has been used in droplet-based microfluidics and is known to provide high droplet stability and biocompatibility. Since this surfactant ensures the stability of droplets, droplet-based microfluidic systems have been widely used to encapsulate and analyze various biological components at the single-molecule scale, including viruses, bacteria, nucleic acids and proteins. In this study, we experimentally confirmed that gas crosstalk occurred between droplets formed by fluorinated oil and the PFPE-PEG-PFPE surfactant. E. coli K-12 bacterial cells were encapsulated with Luria-Bertani broth within droplets for the cultivation, and gas crosstalk was identified with neighboring droplets that contain phenol red. Since bacteria produce ammonia gas during its metabolism, penetration of ammonia gas initiates a color change of phenol red-containing droplets. Ammonia gas exchange was also confirmed by reacting ammonium chloride and sodium hydroxide within droplets that encapsulated. Herein, we demonstrate the gas crosstalk issue between droplets when it is formed using the PFPE-PEG-PFPE surfactant and also confirm that the density of droplet barrier has effects on gas crosstalk. Our results also suggest that droplet-based microfluidics can be used for the monitoring of living bacteria by the determination of bacterial metabolites during cultivation.
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10.
Lipase Catalysis in Presence of Nonionic Surfactants.
Goswami, D
Applied biochemistry and biotechnology. 2020;(2):744-762
Abstract
Lipase can catalyze varieties of reactions at the interface of aqueous and organic phase. Among various alternatives to modify catalytic performance of lipase, the addition of surfactants, particularly nonionic surfactants, has been widely studied. Low concentrations of nonionic surfactants augment lipase catalysis; on increasing surfactant concentration, often the catalytic performance decreases. Mole ratio of water to (nonionic) surfactant also has a profound effect on lipase activity. Catalytic abilities of some lipases are either enhanced or reduced in the presence of all nonionic surfactants of the same type, whereas for some other lipases, nonionic surfactants of the same type have mixed effect. Nonionic surfactant even changes substrate specificity of lipase. Water-in-ionic liquid microemulsion involving nonionic surfactant often performs better than other systems in improving catalytic ability of lipase. Tween and Triton surfactants often enhance enantiomeric separation catalyzed by lipase. Nonionic surfactants significantly affect activities of immobilized lipase, being present either as a component during immobilization or as a component in reaction medium. Lipases coated with nonionic surfactants act better than reverse micelles and microemulsions containing lipase. Thus, nonionic surfactants help lipase catalyzed processes in various media to enhance production of useful compounds like flavor ester, structured lipids, optically pure compounds, and noncrystalline polymers.