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1.
Int J Mol Sci ; 24(14)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37511085

RESUMEN

The introduction of the notion of energy change resulting from the ion exchange in apatites leads to the question: how can some simple isomorphic series be described using the mentioned idea? We concentrated on the simple isomorphic series of compounds: apatite, bioapatite, calcite, aragonite, celestine, K-, Zn- and Cu-Tutton's salts. It was demonstrated in all the series, except Tutton's salts, that the change in energy and the change in the crystal cell volume are, in a simple way, dependent on the change in the ionic radii of the introduced ions. The linear relationships between the variations in energy and in the universal crystallographic dimension d were derived from the earlier equations and proven based on available data. In many cases, except the Tutton's salts, linear dependence was discovered between the change in energy and the sinus of universal angle Θ, corresponding to the change in momentum transfer. In the same cases, linear dependencies were observed between the energy changes and the changes in the volumes of crystallographic cells, and mutually between changes in the crystallographic cell volume V, crystallographic dimension d, and diffraction angle Θ.


Asunto(s)
Carbonato de Calcio , Sales (Química) , Cristalografía , Iones , Apatitas/química , Difracción de Rayos X
2.
Int J Mol Sci ; 24(9)2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37176062

RESUMEN

The chemical composition and structure of bamboo octocoral Keratoisis spp. skeletons were investigated by using: Scanning Electron Microscopy SEM, Raman Microscopy, X-ray Diffraction XRD, Laser Ablation-Inductively Coupled Plasma LA-ICP, and amino acid analyzers. Elements discovered in the nodes (mainly organic parts of the skeleton) of bamboo corals showed a very interesting arrangement in the growth ring areas, most probably enabling the application of bamboo corals as palaeochronometers and palaeothermometers. LA-ICP results showed that these gorgonian corals had an unusually large content of bromine, larger than any other organism yet studied. The local concentration of bromine in the organic part of the growth rings of one of the studied corals grew up to 29,000 ppm of bromine. That is over 440 times more than is contained in marine water and 35 times more than Murex contains, the species which was used to make Tyrian purple in ancient times. The organic matter of corals is called gorgonin, the specific substance that both from the XRD and Raman studies seem to be very similar to the reptile and bird keratins and less similar to the mammalian keratins. The missing cross-linking by S-S bridges, absence of aromatic rings, and significant participation of ß-turn organization of peptides differs gorgonin from keratins. Perhaps, the gorgonin belongs to the affined but still different substances concerning reptile and bird keratin and in relation to the more advanced version-the mammalian one. Chemical components of bamboo corals seem to have great medical potential, with the internodes as material substituting the hard tissues and the nodes as the components of medicines.


Asunto(s)
Antozoos , Animales , Antozoos/química , Bromo , Mamíferos , Microscopía Electrónica de Rastreo , Agua , Espectrometría de Masas , Difracción de Rayos X , Microscopía
3.
Int J Mol Sci ; 24(21)2023 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-37958956

RESUMEN

The matter constituting the enamels of four types of organisms was studied. The variability of the ions was presented in molar units. It was proven that the changes in water contents of the enamel are significantly positively related to changes in Mg; inversely, there is also a strong connection with changes in Ca and P, the main components of bioapatite. The variability in the organic matter has the same strong and positive characteristics and is also coupled with changes in Mg contents. Amelogenins in organic matter, which synthesize enamel rods, likely have a role in adjusting the amount of Mg, thus establishing the amount of organic matter and water in the whole enamel; this adjustment occurs through an unknown mechanism. Ca, P, Mg, and Cl ions, as well as organic matter and water, participate in the main circulation cycle of bioapatites. The selection of variations in the composition of bioapatite occurs only along particular trajectories, where the energy of transformation linearly depends on the following factors: changes in the crystallographic d parameter; the increase in the volume, V, of the crystallographic cell; the momentum transfer, which is indirectly expressed by ΔsinΘ value. To our knowledge, these findings are novel in the literature. The obtained results indicate the different chemical and crystallographic affinities of the enamels of selected animals to the human ones. This is essential when animal bioapatites are transformed into dentistic or medical substitutes for the hard tissues. Moreover, the role of Mg is shown to control the amount of water in the apatite and in detecting organic matter in the enamels.


Asunto(s)
Apatitas , Diente Molar , Humanos , Animales , Apatitas/química , Esmalte Dental , Cristalografía , Iones
4.
Molecules ; 28(11)2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37298844

RESUMEN

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.


Asunto(s)
Antiinfecciosos , Eucalyptus , Aceites Volátiles , Aceites Volátiles/farmacología , Aceites Volátiles/química , Antiinfecciosos/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antivirales , Pseudomonas aeruginosa
5.
Int J Mol Sci ; 23(17)2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-36076932

RESUMEN

Apatites are one of the most intensively studied materials for possible biomedical applications. New perspectives of possible application of apatites correspond with the development of nanomaterials and nanocompounds. Here, an effort to systematize different kinds of human bioapatites forming bones, dentin, and enamel was undertaken. The precursors of bioapatites and hydroxyapatite were also considered. The rigorous consideration of compositions and stoichiometry of bioapatites allowed us to establish an order in their mutual sequence. The chemical reactions describing potential transformations of biomaterials from octacalcium phosphate into hydroxyapatite via all intermediate stages were postulated. Regardless of whether the reactions occur in reality, all apatite biomaterials behave as if they participate in them. To conserve the charge, additional free charges were introduced, with an assumed meaning to be joined with the defects. The distribution of defects was coupled with the values of crystallographic parameters "a" and "c". The energetic balances of bioapatite transformations were calculated. The apatite biomaterials are surprisingly regular structures with non-integer stoichiometric coefficients. The results presented here will be helpful for the further design and development of nanomaterials.


Asunto(s)
Apatitas , Durapatita , Apatitas/química , Materiales Biocompatibles/química , Huesos , Cristalografía , Humanos
6.
Molecules ; 27(10)2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35630828

RESUMEN

This study aimed to determine the use of selected vegetables (pumpkin, cauliflower, broccoli, carrot) as carriers of potassium iodide (KI) and potassium iodate (KIO3) by determining changes in iodine content under various conditions of impregnation as the degree of hydration, impregnated sample temperature, and impregnation time. The influence of these conditions on iodine contents in vegetables after their fortification and storage (21 °C/230 days) was analyzed. The results showed that all selected vegetables could be efficient iodine carriers. However, the conditions of the impregnation process are crucial for fortification efficiency, particularly the degree of hydration and the temperature of the impregnated samples before drying. The results showed that the lowest iodine content was in samples fortified at 4 °C and 1:4 hydration. On the other hand, the highest reproducibility of iodine was for the following fortification conditions: temperature of -76 °C and hydration of 1:1. The studies confirmed the higher stability of iodine in KIO3 form compared to KI. To increase recovery of the introduced iodine in the product after drying, using the conditioning step at 4 °C is not recommended. We recommend freezing vegetables immediately after the impregnation process.


Asunto(s)
Yodo , Yoduro de Potasio , Reproducibilidad de los Resultados , Verduras
7.
Molecules ; 27(24)2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36558043

RESUMEN

Developments in the field of nanostructures open new ways for designing and manufacturing innovative materials. Here, we focused on new original ways of calculating energy changes during the substitution of foreign ions into the structure of apatites and bioapatites. Using these tools, the energetic costs of ion exchanges were calculated for the exemplary cases known from the literature. It was established that the most costly were ion exchanges of some cations inside apatites and of anions, and the least costly exchanges in tetrad channel positions. Real energy expenses for bioapatites are much smaller in comparison to mineral apatites due to the limited involvement of magnesium and carbonates in the structure of hard tissues. They are of the order of several electron volts per ion. The rigorous dependences of the energy changes and crystallographic cell volumes on the ionic radii of introduced cations were proved. The differentiation of the positioning of foreign ions in locations of Ca(I) and Ca(II) could be calculated in the case of a Ca-Pb reaction in hydroxyapatite. The energetic effects of tooth aging were indicated. The ability of energy change calculation during the ion exchange for isomorphic substances widens the advantages resulting from X-ray diffraction measurements.


Asunto(s)
Apatitas , Durapatita , Apatitas/química , Intercambio Iónico , Difracción de Rayos X , Cationes
8.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34199407

RESUMEN

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.


Asunto(s)
Evolución Biológica , Esmalte Dental/química , Dentina/química , Diente/química , Caimanes y Cocodrilos/genética , Animales , Fenómenos Biomecánicos , Esmalte Dental/ultraestructura , Dentina/enzimología , Dinosaurios/genética , Módulo de Elasticidad , Dureza , Humanos , Diente Molar/química , Tiburones/genética , Diente/ultraestructura
9.
Int J Mol Sci ; 22(20)2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34681625

RESUMEN

Chitosan is one of the emerging materials for various applications. The most intensive studies have focused on its use as a biomaterial and for biomedical, cosmetic, and packaging systems. The research on biodegradable food packaging systems over conventional non-biodegradable packaging systems has gained much importance in the last decade. The deacetylation of chitin, a polysaccharide mainly obtained from crustaceans and shrimp shells, yields chitosan. The deacetylation process of chitin leads to the generation of primary amino groups. The functional activity of chitosan is generally owed to this amino group, which imparts inherent antioxidant and antimicrobial activity to the chitosan. Further, since chitosan is a naturally derived polymer, it is biodegradable and safe for human consumption. Food-focused researchers are exploiting the properties of chitosan to develop biodegradable food packaging systems. However, the properties of packaging systems using chitosan can be improved by adding different additives or blending chitosan with other polymers. In this review, we report on the different properties of chitosan that make it suitable for food packaging applications, various methods to develop chitosan-based packaging films, and finally, the applications of chitosan in developing multifunctional food packaging materials. Here we present a short overview of the chitosan-based nanocomposites, beginning with principal properties, selected preparation techniques, and finally, selected current research.


Asunto(s)
Quitosano/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Quitosano/farmacología , Embalaje de Alimentos/métodos , Hongos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos
10.
Int J Mol Sci ; 22(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670768

RESUMEN

Lower levels of calcium in adults increase the risk for osteoporosis, and in children, low calcium levels can impact their potential adult height. The study objective was to analyze the bioavailability and physicochemical properties of a calcium preparation based on chicken eggs. The base calcium preparation was enriched with one of a variety of biologically active substances, inter alia, vitamin D3, vitamin K, lysine, lactose, magnesium chloride and inulin. The newly developed calcium preparations were subjected to structural analysis using X-ray diffraction and scanning electron microscopy, and the hydrodynamic diameter for the molecules was determined using the dynamic light scattering method and their zeta potential. To determine the optimum storage conditions of calcium preparations, their hygroscopicity and bulk density were determined. The calcium preparations were also added to selected food products, such as apple juice with mango, fruit dessert (jelly) and beef meatballs. The enriched food products were subjected to sensory analysis. The study demonstrated the significant influence of additives to calcium preparation in terms of its hygroscopicity and morphology. It was found that all products with the addition of analyzed preparations were characterized by high sensory desirability. The results presented in the study comprise the basis for the development of new food products, enriched with calcium.


Asunto(s)
Cloruro de Calcio/farmacología , Cáscara de Huevo/microbiología , Modelos Biológicos , Sensación , Animales , Cáscara de Huevo/efectos de los fármacos , Hidrodinámica , Tamaño de la Partícula , Sensación/efectos de los fármacos , Electricidad Estática , Difracción de Rayos X
11.
Int J Mol Sci ; 22(2)2021 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-33477381

RESUMEN

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.


Asunto(s)
Aesculus/metabolismo , Cannabis/metabolismo , Emulsionantes/química , Dispersión Dinámica de Luz , Emulsiones/química , Nanopartículas/química , Tamaño de la Partícula , Aceites de Plantas/química , Semillas/metabolismo , Tensoactivos , Temperatura , Viscosidad , Agua
12.
Molecules ; 26(13)2021 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-34279444

RESUMEN

Plant-based protein sources have a characteristic aroma that limits their usage in various meat-alternative formulations. Despite being the most popular plant-based protein, the allergenicity of soy protein severely restricts the potential adoption of soy protein as an animal substitute. Thereby, allergen-free plant-protein sources need to be characterized. Herein, we demonstrate a rapid solid-phase-microextraction gas-chromatography/mass-spectrometry (SPME-GC/MS) technique for comparing the volatile aroma profile concentration of two different allergen-free plant-protein sources (brown rice and pea) and comparing them with soy protein. The extraction procedure consisted of making a 1:7 w/v aqueous plant protein slurry, and then absorbing the volatile compounds on an SPME fibre under agitation for 10 min at 40 °C, which was subsequently injected onto a GC column coupled to an MS system. Observed volatile concentrations were used in conjunction with odour threshold values to generate a Total Volatile Aroma Score for each protein sample. A total of 76 volatile compounds were identified. Aldehydes and furans were determined to be the most dominant volatiles present in the plant proteins. Both brown rice protein and pea protein contained 64% aldehydes and 18% furans, with minor contents of alcohols, ketones and other compounds. On the other hand, soy protein consisted of fewer aldehydes (46%), but a more significant proportion of furans (42%). However, in terms of total concentration, brown rice protein contained the highest intensity and number of volatile compounds. Based on the calculated odour activity values of the detected compounds, our study concludes that pea proteins could be used as a suitable alternative to soy proteins in applications for allergen-free vegan protein products without interfering with the taste or flavour of the product.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Glycine max/química , Odorantes/análisis , Oryza/química , Pisum sativum/química , Proteínas de Plantas/análisis , Compuestos Orgánicos Volátiles/análisis , Alérgenos/química , Microextracción en Fase Sólida
13.
Molecules ; 26(19)2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34641403

RESUMEN

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.


Asunto(s)
Aesculus/química , Cannabis/química , Emulsiones , Nanoestructuras/química , Extractos Vegetales/química , Tensoactivos/química , Proteína de Suero de Leche/química , Reología , Agua/química
14.
Molecules ; 26(24)2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34946779

RESUMEN

Hemp (Cannabis sativa L.) is a herbaceous anemophilous plant that belongs to the Cannabinaceae family. The cannabis seed (hemp) has long been utilized as a food source and is commercially important as an edible oil source. In this review, the positive and negative health effects of cannabis, the relationship between cannabis and various diseases, and the use of cannabis in various food products have been discussed. In addition, the scientific literature on the potential use of cannabis and its derivatives as a dietary supplement for the prevention and treatment of inflammatory and chronic degenerative diseases in animals and humans has been reviewed. Cannabis is being developed as a key ingredient in a variety of food items, including bakery, confectionery, beverages, dairy, fruits, vegetables, and meat. Hemp seeds are high in readily digestible proteins, lipids, polyunsaturated fatty acids (PUFA), insoluble fiber, carbs, and favorable omega-6 PUFA acid to omega-3 PUFA ratio and have high nutritional value. The antioxidants of cannabis, such as polyphenols, help with anxiety, oxidative stress, and the risk of chronic illnesses, including cancer, neurological disorders, digestive problems, and skin diseases. Cannabis has been shown to have negative health impacts on the respiratory system, driving, and psychomotor functions, and the reproductive system. Overall, the purpose of this research is to stimulate more in-depth research on cannabis's adaptation in various foods and for the treatment of chronic illnesses.


Asunto(s)
Cannabis/química , Suplementos Dietéticos , Aditivos Alimentarios , Valor Nutritivo , Semillas/química , Animales , Antioxidantes/química , Humanos , Aceites de Plantas/química , Polifenoles/química
15.
Molecules ; 26(10)2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-34069178

RESUMEN

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.


Asunto(s)
Medicina Tradicional , Aceites de Plantas/química , Antiinfecciosos/farmacología , Bacterias/citología , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Refractometría , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Compuestos Orgánicos Volátiles/análisis
16.
J Dairy Sci ; 103(8): 6918-6929, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32505401

RESUMEN

Hen eggshells are a rich and natural source of calcium and can serve as a biofunctional food ingredient. Enriching the traditional Polish bread spread (sersmazony) with micronized eggshell is an attractive proposition for consumers who require easily available calcium. The present study aimed to evaluate the use of micronized eggshells as a source of bioavailable calcium in bread spread. The study evaluated the effect of selected biocomponents on calcium bioavailability by using an in vitro digestion model. The enrichment of bread spread with eggshell, lysine, vitamin D3, and vitamin K enhanced all examined physicochemical variables except water activity. Enrichment with eggshells increased calcium levels >2.5-fold compared with the control sample. As an ingredient of bread spread, lysine is an important rheological factor. The bioavailability of calcium was higher in samples with lysine and vitamin K compared with samples that contained eggshell alone.


Asunto(s)
Pan , Calcio de la Dieta/administración & dosificación , Calcio/administración & dosificación , Calcio/química , Cáscara de Huevo/química , Alimentos Fortificados , Animales , Disponibilidad Biológica , Pollos , Colecalciferol , Femenino , Polonia
17.
Int J Mol Sci ; 22(1)2020 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-33383975

RESUMEN

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.


Asunto(s)
Materiales Biocompatibles/química , Esmalte Dental/química , Nanoestructuras/química , Diente/química , Fenómenos Químicos , Esmalte Dental/ultraestructura , Humanos , Fenómenos Mecánicos , Modelos Químicos , Diente/ultraestructura , Difracción de Rayos X
18.
Molecules ; 25(9)2020 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-32344920

RESUMEN

Fluorescent submicron particles of fluorinated methacrylate (HFMBA) with long-term stability have been synthesized and characterized with regard to their potential applications. Rhodamine B (RBITC) isothiocyanate was used as the fluorescent component. The core-shell structure of the particles effectively protected the dye against bleaching. HFBMA nanoparticle (NP) stability was confirmed after seven years of storage. Only slight differences were found in the polydispersity index (pdi) from 0.002 to 0.010. Particle size measurements were carried out using dynamic light scattering (DLS), nanoparticle tracking (NTA), and fluorescence correlation spectroscopy (FCS). The hydrodynamic diameter evaluated by different methods were in good agreement, respectively: 184-550 nm, 218-579 nm, and 236-508 nm. Particle and core morphology was estimated by using scanning and transmission electron microscopy (SEM and TEM). The ability to recognize particles in 3D as a reference sample in biological media has been confirmed by epifluorescence optical microscopy, confocal laser scanning microscopy, and super-resolution confocal microscopy (STED).


Asunto(s)
Fluorocarburos/química , Metacrilatos/química , Nanopartículas/química , Colorantes Fluorescentes/química , Microscopía Confocal , Estructura Molecular , Nanopartículas/ultraestructura , Tamaño de la Partícula , Rodaminas/química , Espectrometría de Fluorescencia
19.
Molecules ; 25(11)2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32532010

RESUMEN

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.


Asunto(s)
Cannabis/química , Emulsiones , Extractos Vegetales/farmacología , Aceites de Plantas/química , Pseudomonas fluorescens/crecimiento & desarrollo , Rosaceae/química , Saponinas/farmacología , Pseudomonas fluorescens/efectos de los fármacos
20.
Molecules ; 24(23)2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31775277

RESUMEN

In this paper, we present the possibility of using pea protein isolates as a stabilizer for hempseed oil (HSO)-based water/oil emulsions in conjunction with lecithin as a co-surfactant. A Box-Behnken design was employed to build polynomial models for optimization of the ultrasonication process to prepare the emulsions. The stability of the system was verified by droplet size measurements using dynamic light scattering (DLS) as well as centrifugation and thermal challenge tests. The z-ave droplet diameters of optimized emulsion were 209 and 207 nm after preparation and 1 week storage, respectively. The concentration of free Linoleic acid (C18:2; n-6) was used for calculation of entrapment efficiency in prepared nanoemulsions. At optimum conditions of the process, up to 98.63% ± 1.95 of entrapment was achieved. FTIR analysis and rheological tests were also performed to evaluate the quality of oil and emulsion, and to verify the close-to-water like behavior of the prepared samples compared to the viscous nature of the original oil. Obtained results confirmed the high impact of lecithin and pea protein concentrations on the emulsion droplet size and homogeneity confirmed by microscopic imaging. The presented results are the first steps towards using hempseed oil-based emulsions as a potential food additive carrier, such as flavor. Furthermore, the good stability of the prepared nanoemulsion gives opportunities for potential use in biomedical and cosmetic applications.


Asunto(s)
Emulsiones/química , Aditivos Alimentarios/química , Proteínas de Guisantes/química , Tensoactivos/química , Dispersión Dinámica de Luz , Lecitinas/química , Nanoestructuras/química , Tamaño de la Partícula , Reología , Tensoactivos/farmacología , Viscosidad , Agua/química
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