Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
1.
World J Microbiol Biotechnol ; 40(5): 152, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38553646

RESUMO

Saponins are a large group of compounds, produced mostly by plants as a side product of their metabolic activity. These compounds have attracted much attention over the years mostly because of their surface activity and antibacterial, anti-inflammatory and antifungal properties. On the other hand, most of the hitherto research has concerned the action of saponins against microbial cells as a whole. Therefore, knowing the possible interaction of saponins with biomembrane, we decided to check in-vitro the influence of saponin-rich extract of Saponaria officinalis on spheroplasts of two Candida sp. The obtained results show that 10 mg L- 1 of extract increased the permeability of spheroplasts up to 21.76% relative to that of the control sample. Moreover, the evaluation of surface potential has revealed a decrease by almost 10 mV relative to that of the untreated samples. Such results suggest its direct correlation to integration of saponins into the biomembrane structure. The obtained results have proved the antifungal potential of saponins and their ability of permeabilization of cells. This proves the high potential of saponins use as additives to antifungal pharmaceutics, which is expected to lead to improvement of their action or reduction of required dosage.


Assuntos
Saponaria , Saponinas , Antifúngicos/farmacologia , Antifúngicos/química , Saponaria/química , Saponinas/farmacologia , Saponinas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Candida , Permeabilidade
2.
Molecules ; 28(4)2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36838953

RESUMO

The aim of this study was to determine the effect of saponins-rich plant extract on two model biological membranes: phospholipid monolayers and liposomes. The Langmuir monolayer technique was used to study the interactions of model phospholipid membranes with saponins. The π-A isotherms were determined for DPPE (1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine) monolayer with the addition of various concentrations of licorice saponins extracts and subjected to qualitative as well as quantitative analysis. Additionally, relaxation studies of the obtained monolayers were carried out and morphological changes were examined using Brewster angle microscopy. Moreover, changes in the structure of phospholipid vesicles treated with solutions of saponins-rich plant extracts were assessed using the FTIR technique. The size and zeta potential of the liposomes were estimated based on DLS methods. The obtained results indicated that the saponins interact with the phospholipid membrane formed by DPPE molecules and that the stability of the mixed DPPE/saponins monolayer strongly depends on the presence of impurities in saponins. Furthermore, it was found that the plant extract rich in saponins biosurfactant interacts mainly with the hydrophilic part of liposomes.


Assuntos
Fosfolipídeos , Saponinas , Fosfolipídeos/química , Lipossomos , Saponinas/química , Extratos Vegetais , Propriedades de Superfície
3.
Molecules ; 28(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37446605

RESUMO

The aim of this research was to elucidate the surface active properties of Saponaria officinalis (soapwort) extract containing the plant surfactants saponins. To this end, the advancing contact angle (θ) of water, formamide and diiodomethane on the glass, as well as θ of the aqueous solution of S. officinalis extract fractions on PTFE, PMMA and glass, were studied. Based on the obtained results, the wetting behaviour of saponins was considered with regard to the surface tension components and parameters of the solutions and solids. The investigations also involved the description of the θ isotherms, the dependences between the cosine of contact angle and/or the adhesion of the solution to the solid surfaces and solution surface tension, as well as the critical surface tension of PTFE, PMMA and glass wetting. These dependences were studied based on the saponin adsorption at the different interfaces, which was deduced from the dependence between the adhesion and surface tension of the solution, as well as using the Gibbs and Frumkin isotherm equations. This proved that the saponins are poor wetting agents and that the contact angle isotherm can be described by the exponential function of the second order as well as the Szyszkowski equation, but only for PTFE.


Assuntos
Polimetil Metacrilato , Saponinas , Propriedades de Superfície , Termodinâmica , Água , Politetrafluoretileno
4.
Molecules ; 28(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37298844

RESUMO

Nowadays, due to a higher resistance to drugs, antibiotics, and antiviral medicaments, new ways of fighting pathogens are intensively studied. The alternatives for synthesized compositions are natural products, most of which have been known in natural medicine for a long time. One of the best-known and intensively investigated groups are essential oils (EOs) and their compositions. However, it is worth noting that the method of application can play a second crucial part in the effectiveness of the antimicrobial activity. EOs possess various natural compounds which exhibit antimicrobial activity. One of the compositions which is based on the five main ingredients of eucalyptus, cinnamon, clove, rosemary, and lemon is named "five thieves' oil" (Polish name: olejek pieciu zlodziei) (5TO) and is used in natural medicine. In this study, we focused on the droplet size distribution of 5TO during the nebulization process, evaluated by the microscopic droplet size analysis (MDSA) method. Furthermore, viscosity studies, as well as UV-Vis of the 5TO suspensions in medical solvents such as physiological salt and hyaluronic acid, were presented, along with measurements of refractive index, turbidity, pH, contact angle, and surface tension. Additional studies on the biological activity of 5TO solutions were made on the P. aeruginosa strain NFT3. This study opens a way for the possible use of 5TO solutions or emulsion systems for active antimicrobial applications, i.e., for surface spraying.


Assuntos
Anti-Infecciosos , Eucalyptus , Óleos Voláteis , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antivirais , Pseudomonas aeruginosa
5.
World J Microbiol Biotechnol ; 39(8): 221, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37273071

RESUMO

Large-scale use of nitrofurans is associated with a number of risks related to a growing resistance to these compounds and the toxic effects following from their increasing presence in wastewater and the environment. The aim of the study was to investigate an impact of natural surfactant, saponins from Sapindus mukorossi, on antimicrobial properties of nitrofuran antibiotics. Measurements of bacterial metabolic activity indicated a synergistic bactericidal effect in samples with nitrofurantoin or furazolidone, to which saponins were added. Their addition led to more than 50% greater reduction in viable cells than in the samples without saponins. On the other hand, no toxic effect against human colon epithelial cell was observed. It was found that exposure to antibiotics and surfactants caused the cell membranes to be dominated by branched fatty acids. Moreover, the presence of saponins reduced the hydrophobicity of the cell surface making them almost completely hydrophilic. The results have confirmed a high affinity of saponins to the cells of Pseudomonas strains. Their beneficial synergistic effect on the action of antibiotics from the nitrofuran group was also demonstrated. This result opens promising prospects for the use of saponins from S. mukorossi as an adjuvant to reduce the emission of antibiotics into the environment.


Assuntos
Nitrofuranos , Saponinas , Humanos , Antibacterianos/farmacologia , Saponinas/farmacologia , Nitrofuranos/farmacologia , Pseudomonas , Tensoativos , Células Epiteliais , Colo
6.
Molecules ; 27(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36235114

RESUMO

The bioavailability of organic compounds to bacterial cells is crucial for their vital activities. This includes both compounds that are desirable to the cells (e.g., sources of energy, carbon, nitrogen, and other nutrients) and undesirable compounds that are toxic to the cells. For this reason, bioavailability is an issue of great importance in many areas of human activity that are related to bacteria, e.g., biotechnological production, bioremediation of organic pollutants, and the use of antibiotics. This article proposes a classification of factors determining bioavailability, dividing them into factors at the physicochemical level (i.e., those related to the solubility of a chemical compound and its transport in aqueous solution) and factors at the microbiological level (i.e., those related to adsorption on the cell surface and those related to transport into the cell). Awareness of the importance of and the mechanisms governing each of the factors described allows their use to change bioavailability in the desired direction.


Assuntos
Carbono , Poluentes Ambientais , Antibacterianos/farmacologia , Disponibilidade Biológica , Carbono/química , Humanos , Nitrogênio
7.
Molecules ; 27(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209143

RESUMO

The occurrence of 17α-ethinylestradiol (EE2) in the environment and its removal have drawn special attention from the scientific community in recent years, due to its hazardous effects on human and wildlife around the world. Therefore, the aim of this study was to produce an efficient enzymatic system for the removal of EE2 from aqueous solutions. For the first time, commercial silica nanopowder and 3D fibrous chitinous scaffolds from Aplysina fistularis marine sponge were used as supports for horseradish peroxidase (HRP) immobilization. The effect of several process parameters onto the removal mechanism of EE2 by enzymatic conversion and adsorption of EE2 were investigated here, including system type, pH, temperature and concentrations of H2O2 and EE2. It was possible to fully remove EE2 from aqueous solutions using system SiO2(HRP)-chitin(HRP) over a wide investigated pH range (5-9) and temperature ranges (4-45 °C). Moreover, the most suitable process conditions have been determined at pH 7, temperature 25 °C and H2O2 and EE2 concentrations equaling 2 mM and 1 mg/L, respectively. As determined, it was possible to reuse the nanoSiO2(HRP)-chitin(HRP) system to obtain even 55% EE2 degradation efficiency after five consecutive catalytic cycles.


Assuntos
Quitina/química , Etinilestradiol/química , Peroxidase do Rábano Silvestre/química , Nanopartículas/química , Dióxido de Silício/química , Poluentes Químicos da Água/química , Adsorção , Biocatálise , Fenômenos Químicos , Enzimas Imobilizadas , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura , Análise Espectral , Temperatura
8.
Microb Cell Fact ; 20(1): 40, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33557838

RESUMO

BACKGROUND: Microbial surfactants called biosurfactants, thanks to their high biodegradability, low toxicity and stability can be used not only in bioremediation and oil processing, but also in the food and cosmetic industries, and even in medicine. However, the high production costs of microbial surfactants and low efficiency limit their large-scale production. This requires optimization of management conditions, including the possibility of using waste as a carbon source, such as food processing by-products. This papers describes the production and characterization of the biosurfactant obtained from the endophytic bacterial strain Bacillus pumilus 2A grown on various by-products of food processing and its potential applications in supporting plant growth. Four different carbon and nitrogen sources, pH, inoculum concentration and temperature were optimized within Taguchi method. RESULTS: Optimization of bioprocess within Taguchi method and experimental analysis revealed that the optimal conditions for biosurfactant production were brewer's spent grain (5% w/v), ammonium nitrate (1% w/v), pH of 6, 5% of inoculum, and temperature at 30 °C, leading to 6.8 g/L of biosurfactant. Based on gas chromatography-mass spectrometry and Fourier transform infrared spectroscopy analysis produced biosurfactant was determined as glycolipid. Obtained biosurfactant has shown high and long term thermostability, surface tension of 47.7 mN/m, oil displacement of 8 cm and the emulsion index of 69.11%. The examined glycolipid, used in a concentration of 0.2% significantly enhanced growth of Phaseolus vulgaris L. (bean), Raphanus L. (radish), Beta vulgaris L. (beetroot). CONCLUSIONS: The endophytic Bacillus pumilus 2A produce glycolipid biosurfactant with high and long tem thermostability, what makes it useful for many purposes including food processing. The use of brewer's spent grain as the sole carbon source makes the production of biosurfactants profitable, and from an environmental point of view, it is an environmentally friendly way to remove food processing by products. Glycolipid produced by endophytic Bacillus pumilus 2A significantly improve growth of Phaseolus vulgaris L. (bean), Raphanus L. (radish), Beta vulgaris L. (beetroot). Obtained results provide new insight to the possible use of glycolipids as plant growth promoting agents.


Assuntos
Bacillus pumilus , Beta vulgaris/crescimento & desenvolvimento , Endófitos , Phaseolus/crescimento & desenvolvimento , Raphanus/crescimento & desenvolvimento , Tensoativos , Bacillus pumilus/química , Bacillus pumilus/metabolismo , Endófitos/química , Endófitos/metabolismo , Tensoativos/isolamento & purificação , Tensoativos/metabolismo , Tensoativos/farmacologia
9.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199407

RESUMO

The dentin-enamel junction (DEJ) is known for its special role in teeth. Several techniques were applied for the investigation of the DEJ in human sound molar teeth. The electron (EPMA) and proton (PIXE) microprobes gave consistent indications about the variability of elemental concentrations on this boundary. The locally increased and oscillating concentrations of Mg and Na were observed in the junction, in the layer adhering to the enamel and covering roughly half of the DEJ width. The chemical results were compared with the optical profiles of the junction. Our chemical and optical results were next compared with the micromechanical results (hardness, elastic modulus, friction coefficient) available in the world literature. A strong correlation of both result sets was proven, which testifies to the self-affinity of the junction structures for different locations and even for different kinds of teeth and techniques applied for studies. Energetic changes in tooth strictly connected with crystallographic transformations were calculated, and the minimum energetic status was discovered for DEJ zone. Modeling of both walls of the DEJ from optical data was demonstrated. Comparing the DEJ in human teeth with the same structure found in dinosaur, shark, and alligator teeth evidences the universality of dentin enamel junction in animal world. The paper makes a contribution to better understanding the joining of the different hard tissues.


Assuntos
Evolução Biológica , Esmalte Dentário/química , Dentina/química , Dente/química , Jacarés e Crocodilos/genética , Animais , Fenômenos Biomecânicos , Esmalte Dentário/ultraestrutura , Dentina/enzimologia , Dinossauros/genética , Módulo de Elasticidade , Dureza , Humanos , Dente Molar/química , Tubarões/genética , Dente/ultraestrutura
10.
Int J Mol Sci ; 22(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671749

RESUMO

(1) Background: Environmental contamination with antibiotics is particularly serious because the usual methods used in wastewater treatment plants turn out to be insufficient or ineffective. An interesting idea is to support natural biodegradation processes with physicochemical methods as well as with bioaugmentation with efficient microbial degraders. Hence, the aim of our study is evaluation of the effectiveness of different methods of nitrofurazone (NFZ) degradation: photolysis and photodegradation in the presence of two photocatalysts, the commercial TiO2-P25 and a self-obtained Fe3O4@SiO2/TiO2 magnetic photocatalyst. (2) Methods: The chemical nature of the photocatalysis products was investigated using a spectrometric method, and then, they were subjected to biodegradation using the strain Achromobacter xylosoxidans NFZ2. Additionally, the effects of the photodegradation products on bacterial cell surface properties and membranes were studied. (3) Results: Photocatalysis with TiO2-P25 allowed reduction of NFZ by over 90%, demonstrating that this method is twice as effective as photolysis alone. Moreover, the bacterial strain used proved to be effective in the removal of NFZ, as well as its intermediates. (4) Conclusions: The results indicated that photocatalysis alone or coupled with biodegradation with the strain A. xylosoxidans NFZ2 leads to efficient degradation and almost complete mineralization of NFZ.


Assuntos
Achromobacter denitrificans/metabolismo , Nitrofurazona/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Achromobacter denitrificans/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Biodegradação Ambiental , Catálise , Nitrofurazona/química , Nitrofurazona/toxicidade , Processos Fotoquímicos , Fotólise , Dióxido de Silício/química , Espectrofotometria Infravermelho , Titânio/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
11.
Int J Mol Sci ; 22(2)2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33477381

RESUMO

Nanoemulsion systems receive a significant amount of interest nowadays due to their promising potential in biomedicine and food technology. Using a two-step process, we produced a series of nanoemulsion systems with different concentrations of hemp seed oil (HSO) stabilized with Aesculus hippocastanum L. extract (AHE). Water and commercially-available low-concentrated hyaluronic acid (HA) were used as the liquid phase. Stability tests, including an emulsifying index (EI), and droplet size distribution tests performed by dynamic light scattering (DLS) proved the beneficial impact of AHE on the emulsion's stability. After 7 days of storage, the EI for the water-based system was found to be around 100%, unlike the HA systems. The highest stability was achieved by an emulsion containing 5% HSO and 2 g/L AHE in water, as well as the HA solution. In order to obtain the detailed characteristics of the emulsions, UV-Vis and FTIR spectra were recorded, and the viscosity of the samples was determined. Finally, a visible microscopic analysis was used for the homogeneity evaluation of the samples, and was compared with the DLS results of the water system emulsion, which showed a desirable stability. The presented results demonstrate the possible use of oil emulsions based on a plant extract rich in saponins, such as AHE. Furthermore, it was found that the anti-inflammatory properties of AHE provide opportunities for the development of new emulsion formulations with health benefits.


Assuntos
Aesculus/metabolismo , Cannabis/metabolismo , Emulsificantes/química , Difusão Dinâmica da Luz , Emulsões/química , Nanopartículas/química , Tamanho da Partícula , Óleos de Plantas/química , Sementes/metabolismo , Tensoativos , Temperatura , Viscosidade , Água
12.
Molecules ; 26(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34641403

RESUMO

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.


Assuntos
Aesculus/química , Cannabis/química , Emulsões , Nanoestruturas/química , Extratos Vegetais/química , Tensoativos/química , Proteínas do Soro do Leite/química , Reologia , Água/química
13.
Molecules ; 26(10)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069178

RESUMO

To meet the growing interest in natural antibacterial agents, we evaluated the physicochemical and biological properties of the folk medicine known as "five thieves' oil" (Polish name: olejek pieciu zlodziei). Five thieves' oil consists of a mixture of five oils: rosemary, lemon, clove, eucalyptus, and cinnamon. In this study, we performed gas chromatography, FTIR, and UV-vis spectroscopic analysis, as well as L-a-b color tests, contact angle determination, and surface tension determination. To verify its antibacterial activity, the metabolic activity and changes in cell membrane permeability of bacteria of the genus Pseudomonas were studied. As a result, it was found that among the constituent oils, the oils of clove and cinnamon were the least volatile and, at the same time, had the strongest antibacterial activity. However, a mix of all the oils also showed comparable activity, which was even more pronounced for the oils after 4 weeks of aging. This effect can be linked to the high content of terpene derivatives such as eugenol and cinnamaldehyde, which can cause changes in bacterial membrane permeability, affecting cell activity and survival. This study is the first to characterize the constituents of the popular folk medicine five thieves' oil, confirming and explaining its strong antibacterial activity, thus constituting a significant contribution to contemporary health education.


Assuntos
Medicina Tradicional , Óleos de Plantas/química , Anti-Infecciosos/farmacologia , Bactérias/citologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Refratometria , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Compostos Orgânicos Voláteis/análise
14.
Int J Mol Sci ; 21(18)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32947916

RESUMO

Diclofenac (DCF) constitutes one of the most significant ecopollutants detected in various environmental matrices. Biological clean-up technologies that rely on xenobiotics-degrading microorganisms are considered as a valuable alternative for chemical oxidation methods. Up to now, the knowledge about DCF multi-level influence on bacterial cells is fragmentary. In this study, we evaluate the degradation potential and impact of DCF on Pseudomonas moorei KB4 strain. In mono-substrate culture KB4 metabolized 0.5 mg L-1 of DCF, but supplementation with glucose (Glc) and sodium acetate (SA) increased degraded doses up to 1 mg L-1 within 12 days. For all established conditions, 4'-OH-DCF and DCF-lactam were identified. Gene expression analysis revealed the up-regulation of selected genes encoding biotransformation enzymes in the presence of DCF, in both mono-substrate and co-metabolic conditions. The multifactorial analysis of KB4 cell exposure to DCF showed a decrease in the zeta-potential with a simultaneous increase in the cell wall hydrophobicity. Magnified membrane permeability was coupled with the significant increase in the branched (19:0 anteiso) and cyclopropane (17:0 cyclo) fatty acid accompanied with reduced amounts of unsaturated ones. DCF injures the cells which is expressed by raised activities of acid and alkaline phosphatases as well as formation of lipids peroxidation products (LPX). The elevated activity of superoxide dismutase (SOD) and catalase (CAT) testified that DCF induced oxidative stress.


Assuntos
Anti-Inflamatórios não Esteroides/metabolismo , Proteínas de Bactérias/metabolismo , Diclofenaco/metabolismo , Pseudomonas/metabolismo , Poluentes Químicos da Água/metabolismo , Anti-Inflamatórios não Esteroides/farmacologia , Proteínas de Bactérias/genética , Biodegradação Ambiental , Biotransformação/genética , Catalase/genética , Catalase/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Meios de Cultura/farmacologia , Diclofenaco/farmacologia , Dioxigenases/genética , Dioxigenases/metabolismo , Indução Enzimática/efeitos dos fármacos , Ácidos Graxos/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos de Membrana/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pseudomonas/efeitos dos fármacos , Acetato de Sódio/farmacologia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/farmacologia
15.
Int J Mol Sci ; 22(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383975

RESUMO

A series of linear profiles of the elements of the enamel in human molar teeth were made with the use of an electron microprobe and a Raman microscope. It is postulated that the enamel can be treated as the superposition of variable "overbuilt" enamel on the stable "core" enamel at the macro-, micro- and nanoscale level. The excessive values characterize the "overbuilt enamel". All the profiles of excessive parameters along the enamel thickness from the enamel surface to the dentin enamel junction (DEJ) can be approximated very precisely with the use of exponential functions, where Ca, P, Cl and F spatial profiles are decaying while Mg, Na, K and CO32- ones are growing distributions. The "overbuilt" apatite formed on the boundary with DEJ, enriched in Na, Mg, OH and carbonates, reacts continuously with Ca, Cl and F, passing into an acid-resistant form of the "overbuilt" enamel. The apparent phases arriving in boundary regions of the "overbuilt enamel" were proposed. Microdiffraction measurements reveal relative variation of energy levels during enamel transformations. Our investigations are the milestones for a further new class of biomaterial and nanomaterial development for biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Esmalte Dentário/química , Nanoestruturas/química , Dente/química , Fenômenos Químicos , Esmalte Dentário/ultraestrutura , Humanos , Fenômenos Mecânicos , Modelos Químicos , Dente/ultraestrutura , Difração de Raios X
16.
Molecules ; 25(11)2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32481761

RESUMO

Due to the increasing use of antibiotics, measures are being taken to improve their removal from the natural environment. The support of biodegradation with natural surfactants that increase the bioavailability of impurities for microorganisms that degrade them, raises questions about their effect on bacterial cells. In this paper we present analysis of the interaction of nitrofurantoin (NFT) and saponins from the Saponaria officinalis on the environmental bacteria membrane and the model phospholipid membrane mimicking it. A wide perspective of the process is provided with the Langmuir monolayer technique and membrane permeability test with bacteria. The obtained results showed that above critical micelle concentration (CMC), saponin molecules are incorporated into the POPE monolayer, but the NFT impact was ambiguous. What is more, differences in membrane permeability between the cells exposed to NFT in comparison to that of the non-exposed cells were observed above 1.0 CMC for Achromobacter sp. KW1 or above 0.5 CMC for Pseudomonas sp. MChB. In both cases, NFT presence lowered the membrane permeability. Moreover, the Congo red adhesion to the cell membrane also decreased in the presence of a high concentration of surfactants and NFT. The results suggest that saponins are incorporated into the bacteria membrane, but their sugar hydrophilic part remains outside, which modifies the adsorption properties of the cell surface as well as the membrane permeability.


Assuntos
Membrana Celular/metabolismo , Nitrofurantoína/química , Fosfolipídeos/química , Tensoativos/química , Biodegradação Ambiental , Membrana Celular/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Nitrofurantoína/farmacologia , Tensoativos/farmacologia
17.
Molecules ; 25(11)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32532010

RESUMO

In this study, two saponins-rich plant extracts, viz. Saponaria officinalis and Quillaja saponaria, were used as surfactants in an oil-in-water (O/W) emulsion based on hempseed oil (HSO). This study focused on a low oil phase content of 2% v/v HSO to investigate stable emulsion systems under minimum oil phase conditions. Emulsion stability was characterized by the emulsification index (EI), centrifugation tests, droplet size distribution as well as microscopic imaging. The smallest droplets recorded by dynamic light scattering (droplets size v. number), one day after the preparation of the emulsion, were around 50-120 nm depending the on use of Saponaria and Quillaja as a surfactant and corresponding to critical micelle concentration (CMC) in the range 0-2 g/L. The surface and interfacial tension of the emulsion components were studied as well. The effect of emulsions on environmental bacteria strains was also investigated. It was observed that emulsions with Saponaria officinalis extract exhibited slight toxic activity (the cell metabolic activity reduced to 80%), in contrast to Quillaja emulsion, which induced Pseudomonas fluorescens ATCC 17400 growth. The highest-stability samples were those with doubled CMC concentration. The presented results demonstrate a possible use of oil emulsions based on plant extract rich in saponins for the food industry, biomedical and cosmetics applications, and nanoemulsion preparations.


Assuntos
Cannabis/química , Emulsões , Extratos Vegetais/farmacologia , Óleos de Plantas/química , Pseudomonas fluorescens/crescimento & desenvolvimento , Rosaceae/química , Saponinas/farmacologia , Pseudomonas fluorescens/efeitos dos fármacos
18.
Ecotoxicol Environ Saf ; 185: 109707, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31561078

RESUMO

Effective biodegradation of hydrophobic pollutants, such as 1-chloronaphthalene, is strictly associated with the adaptation of environmental bacteria to their assimilation. This study explores the relation between the modifications of cell properties of bacteria belonging to Pseudomonas and Serratia genera resulting from a 12-month exposure to 1-chloronaphthalene, and their biodegradation efficiency. In the presented study, both bacterial strains exhibited higher (70%) degradation of this compound after exposure compared to unexposed (55%) systems. This adaptation can be associated with increased ratio of polysaccharides in the outer layers of bacterial cells, which was confirmed using infrared spectroscopy analysis. Additionally, the analysis of Raman spectra indicated conformational changes of extracellular carbohydrates from α- to ß-anomeric structure. Moreover, the changes in the cell surface hydrophobicity and cell membrane permeability differed between the strains and the Pseudomonas strain exhibited more significant modifications of these parameters. The results suggest that adaptation strategies of both tested strains are different and involve diverse reconstructions of the cell wall and membranes. The results provide a novel and deep insight into the interactions between environmental bacterial strains and chloroaromatic compounds, which opens new perspectives for applying spectrometric methods in investigation of cell adaptation strategies as a result of long-term contact with toxic pollutants.


Assuntos
Aclimatação/efeitos dos fármacos , Poluentes Ambientais/análise , Naftalenos/análise , Pseudomonas/efeitos dos fármacos , Serratia/efeitos dos fármacos , Biodegradação Ambiental , Poluentes Ambientais/toxicidade , Interações Hidrofóbicas e Hidrofílicas , Naftalenos/toxicidade , Polissacarídeos Bacterianos/metabolismo , Pseudomonas/metabolismo , Serratia/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-30614383

RESUMO

Increasing use of biosurfactants has stimulated the search for new and efficient biosurfactant-producing bacterial strains, preferably nonpathogenic ones. The aim of the present study was to characterize a new isolated Pseudomonas sp. KZ1 strain and its exocellular surface active compounds. After examining several mineral media of different compositions, the bioreactor-scale production of biosurfactants under optimum conditions was tested. Then, the composition of the isolated biosurfactants was investigated by Fourier-transform infrared spectroscopy and gas chromatography-mass spectrometry analysis and their surface active properties were characterized by adsorption parameters. The results indicated that the Pseudomonas sp. KZ1 biosurfactant had the critical micelle concentration of 0.12 g L-1 and decreased the surface tension decreased to 31.7 mN m-1. Moreover, the biosurfactant increased the rate of biodegradation of diesel oil by the strains: Pseudomonas sp. KZ1, Pseudomonas sp. OS4 and Achromobacter sp. KW1. The obtained biosurfactant showing attractive properties is a promising and much 'greener' alternative in the application for surfactant-enhanced biodegradation of hydrocarbons.


Assuntos
Biodegradação Ambiental , Pseudomonas/metabolismo , Tensoativos/química , Achromobacter/metabolismo , Reatores Biológicos , Cromatografia Gasosa-Espectrometria de Massas , Gasolina , Hidrocarbonetos/metabolismo , Micelas , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Molecules ; 22(10)2017 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-28991215

RESUMO

Ibuprofen is one of the most often detected pollutants in the environment, particularly at landfill sites and in wastewaters. Contamination with pharmaceuticals is often accompanied by the presence of other compounds which may influence their degradation. This work describes the new degradation pathway of ibuprofen by Bacillus thuringiensis B1(2015b), focusing on enzymes engaged in this process. It is known that the key intermediate which transformation limits the velocity of the degradation process is hydroxyibuprofen. As the degradation rate also depends on various factors, the influence of selected heavy metals and aromatic compounds on ibuprofen degradation by the B1(2015b) strain was examined. Based on the values of non-observed effect concentration (NOEC) it was found that the toxicity of tested metals increases from Hg(II) < Cu(II) < Cd(II) < Co(II) < Cr(VI). Despite the toxic effect of metals, the biodegradation of ibuprofen was observed. The addition of Co2+ ions into the medium significantly extended the time necessary for the complete removal of ibuprofen. It was shown that Bacillus thuringiensis B1(2015b) was able to degrade ibuprofen in the presence of phenol, benzoate, and 2-chlorophenol. Moreover, along with the removal of ibuprofen, degradation of phenol and benzoate was observed. Introduction of 4-chlorophenol into the culture completely inhibits degradation of ibuprofen.


Assuntos
Anti-Inflamatórios não Esteroides/metabolismo , Bacillus thuringiensis/metabolismo , Ibuprofeno/metabolismo , Poluentes Químicos da Água/metabolismo , Anti-Inflamatórios não Esteroides/química , Biodegradação Ambiental , Ibuprofeno/análogos & derivados , Ibuprofeno/química , Cinética , Metais Pesados/metabolismo , Águas Residuárias/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA