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1.
Int J Mol Sci ; 24(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36674526

RESUMO

This paper discusses the state of advancement in the development of spectroscopic methods based on the use of mid (proper) infrared radiation in the context of applications in various fields of science and technology. The authors drew attention to the most important solutions specific to both spectroscopy itself (ATR technique) and chemometric data processing tools (PCA and PLS models). The objective of the current paper is to collect and consistently present information on various aspects of FT-IR spectroscopy, which is not only a well-known and well-established method but is also continuously developing. The innovative aspect of the current review is to show FT-IR's great versatility that allows its applications to solve and explain issues from both the scientific domain (e.g., hydrogen bonds) and practical ones (e.g., technological processes, medicine, environmental protection, and food analysis). Particular attention was paid to the issue of hydrogen bonds as key non-covalent interactions, conditioning the existence of living matter and determining the number of physicochemical properties of various materials. Since the role of FT-IR spectroscopy in the field of hydrogen bond research has great significance, a historical outline of the most important qualitative and quantitative hydrogen bond theories is provided. In addition, research on selected unconventional spectral effects resulting from the substitution of protons with deuterons in hydrogen bridges is presented. The state-of-the-art and originality of the current review are that it presents a combination of uses of FT-IR spectroscopy to explain the way molecules vibrate and the effects of those vibrations on macroscopic properties, hence practical applications of given substances.


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
2.
BMC Vet Res ; 18(1): 298, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35922808

RESUMO

High stocking densities, closed animal houses, and elevated concentrations of bacteria, fungi, and the products of their activity, including ammonia and hydrogen sulphide, have adverse health effects. Active techniques used to reduce unfavourable environmental conditions, such as ventilation, sprinkling, bedding sorbents, and nutritional treatments, are not always sufficient to improve the animals' living environment. The current paper aims to evaluate the effect of radiant catalytic ionization (RCI) on airborne microorganisms, cage microbiological status, gaseous ammonia concentrations, and the haematological status of mice in animal houses. After one week of operation of an RCI system, the number of airborne bacteria and fungi in the experimental room decreased in comparison to the first day of the experiment (p < 0.05 and p < 0.05 respectively), as did the concentrations of ammonia (p < 0.01) and dust. At the same time, the basic health parameters of the mice, determined in the blood, were very similar between the control and experimental room. RCI seems to be an ideal solution to ensure high hygiene standards in animal rooms and houses with limited use of disinfectants or antibiotic treatment of sick animals. An additional, environmental benefit is the limited amount of nitrogen released.


Assuntos
Amônia , Roedores , Alérgenos , Amônia/análise , Animais , Bactérias , Poeira/análise , Fungos , Abrigo para Animais , Camundongos , Ventilação
3.
Molecules ; 25(8)2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32340398

RESUMO

Finding an effective muscle regeneration technique is a priority for regenerative medicine. It is known that the key factors determining tissue formation include cells, capable of proliferating and/or differentiating, a niche (surface) allowing their colonization and growth factors. The interaction between these factors, especially between the surface of the artificial niche and growth factors, is not entirely clear. Moreover, it seems that the use of a complex of complementary growth factors instead of a few strictly defined ones could increase the effectiveness of tissue maturation, including muscle tissue. In this study, we evaluated whether graphene oxide (GO) nanofilm, chicken embryo muscle extract (CEME), and GO combined with CEME would affect the differentiation and functional maturation of muscle precursor cells, as well as the ability to spontaneously contract a pseudo-tissue muscle. CEME was extracted on day 18 of embryogenesis. Muscle cells obtained from an 8-day-old chicken embryo limb bud were treated with GO and CEME. Cell morphology and differentiation were observed using different microscopy methods. Cytotoxicity and viability of cells were measured by lactate dehydrogenase and Vybrant Cell Proliferation assays. Gene expression of myogenic regulatory genes was measured by Real-Time PCR. Our results demonstrate that CEME, independent of the culture surface, was the main factor influencing the intense differentiation of muscle progenitor cells. The present results, for the first time, clearly demonstrated that the cultured tissue-like structure was capable of inducing contractions without externally applied impulses. It has been indicated that a small amount of CEME in media (about 1%) allows the culture of pseudo-tissue muscle capable of spontaneous contraction. The study showed that the graphene oxide may be used as a niche for differentiating muscle cells, but the decisive influence on the maturation of muscle tissue, especially muscle contractions, depends on the complexity of the applied growth factors.


Assuntos
Produtos Biológicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Grafite/química , Contração Muscular/efeitos dos fármacos , Mioblastos/efeitos dos fármacos , Nanoestruturas/química , Animais , Embrião de Galinha , Expressão Gênica , Grafite/farmacologia , Microscopia de Força Atômica , Nanoestruturas/ultraestrutura
4.
Foods ; 13(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731741

RESUMO

The current investigations were aimed at the determination of the hydrolytic and oxidative stability of commercial pomegranate seed oils provided by four different producers, and to assess the oils' primary quality parameters. During storage, many changes occur in oils that can significantly affect their quality. The oils were tested for acid and peroxide values, fatty acid profile, and their distribution between the sn-1,3 and sn-2 positions of triacylglycerols. The oxidative stability was also determined, and melting curves were plotted for the oils. The analyzed oils were stored for one month in a dark place at refrigerator temperature. Based on the obtained results, it was found that the acid values for most oils did not exceed the permissible level determined by the Codex Alimentarius. However, in all oils, the peroxide value exceeded the permissible level set by the standard EN ISO 3960:2017-03 and the Codex Alimentarius after the one-month storage period. The examined pomegranate seed oils were found to be valuable sources of polyunsaturated fatty acids, especially punicic acid, which was the most abundant fatty acid present in these oils. In all analyzed oils, linoleic acid predominated in the sn-2 position of the triacylglycerols. Pomegranate seed oils did not exhibit good oxidative stability, as the oxidation induction times for all tested oils were very short. The storage period significantly affected the content of the primary oxidation products and oxidative stability of the oils.

5.
J Inflamm Res ; 16: 3739-3761, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663761

RESUMO

Background: The various growth factors change the phenotype of neoplastic cells from sedentary (epithelial) to invasive (mesenchymal), which weaken intercellular connections and promote chemotaxis. It can be assumed that the use of anti-inflammatory polyhydroxyfull nanofilms will restore the sedentary phenotype of neoplastic cells in the primary site of the tumor and, consequently, increase the effectiveness of the therapy. Methods: The studies were carried out on liver cancer cells HepG2, C3A and SNU-449, and non-cancer hepatic cell line THLE-3. Transforming growth factor (TGF), epidermal growth factor and tumor necrosis factor were used to induce the epithelial-mesenchymal transition. C60(OH)40 nanofilm was used to induce the mesenchymal-epithelial transition. Obtaining an invasive phenotype was confirmed on the basis of changes in the morphology using inverted light microscopy. RT-PCR was used to confirm mesenchymal or epithelial phenotype based on e-cadherin, snail, vimentin expression or others. Water colloids at a concentration of 100 mg/L were used to create nanofilms of fullerene, fullerenol, diamond and graphene oxide. The ELISA test for the determination of TGF expression and growth factor antibody array were used to select the most anti-inflammatory carbon nanofilm. Mitochondrial activity and proliferation of cells were measured by XTT and BrdU tests. Results: Cells lost their natural morphology of cells growing in clusters and resembled fibroblast cells after adding a cocktail of factors. Among the four allotropic forms of carbon tested, only the C60(OH)40 nanofilm inhibited the secretion of TGF in all the cell lines used and inhibited the secretion of other factors, including insulin-like growth factor system. Nanofilm C60(OH)40 was non-toxic to liver cells and inhibited the TGF-ß1/Smad pathway of invasive cells treated with the growth factor cocktail. Conclusion: The introduction of an anti-inflammatory, nontoxic component that can induce the mesenchymal-epithelial transition of cancer cells may represent a future adjuvant therapy after tumor resection.

6.
Plants (Basel) ; 12(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36771545

RESUMO

Pollution with microplastics (MPs), nanoplastics (NPs) and trace elements (TEs) remains a considerable threat for mangrove biomes due to their capability to capture pollutants suspended in the water. This study investigated the abundance and composition of plastics and TEs contained in the soil and pneumatophores of Avicennia alba sampled in experimental areas (hotel, market, river mouth, port, and rural areas) differentiated in anthropopressure, located in Bima Bay, Indonesia. Polymers were extracted and analyzed with the use of a modified sediment isolation method and Fourier transform infrared spectroscopy. Trace elements were detected by inductively coupled plasma optical emission spectrometry. The lowest and highest quantities of MPs in soil were recorded in rural and hotel areas, respectively. The rural site was characterized by distinct MP composition. The amounts of sediment-trapped MPs in the tested localities should be considered as high, and the recognized polymers partly corresponded with local human activity. Concentrations of seven plastic types found in plant tissues did not entirely reflect sediment pollution with nine types, suggesting a selective accumulation (particularly of polyamides and vinylidene chloride) and substance migration from other areas. Very low concentrations of non-biogenic TEs were observed, both in sediments and pneumatophores. The results highlight the relevance of environmental contamination with plastics.

7.
Nanotechnol Sci Appl ; 16: 1-18, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36699443

RESUMO

Aim: The experiments aimed to document the presence of the ACE2 receptor on human muscle cells and the effects of the interaction of these cells with the spike protein of the SARS-CoV-2 virus in terms of induction of pro-inflammatory proteins, as well as to assess the possibility of reducing the pool of these proteins with the use of graphene oxide (GO) flakes. Methods: Human Skeletal Myoblast (HSkM), purchased from Gibco were maintained in standard condition according to the manufacturer's instruction. The cells were divided into 4 groups; 1. C-control, 2. S-with addition of spike protein, 3. GO-with the addition of graphene oxide, 4. GO-S-with addition of GO followed by the addition of S protein. Protein S (PX-COV-P049) was purchased from ProteoGenix (France). GO was obtained from Advanced Graphene Products (Zielona Gora, Poland). The influence of all the factors on the morphology of cells was investigated using light and confocal microscopy. ACE2 protein expression on muscle cells was visualized and 40 pro-inflammatory cytokines were investigated using the membrane antibody array method. The protein profile of the lysate of cells from individual groups was also analyzed by mass spectrometry. Conclusion: The experiments confirmed the presence of the ACE2 receptor in human skeletal muscle cells. It has also been documented that the SARS-CoV-2 virus spike protein influences the activation of selected pro-inflammatory proteins that promote cytokine storm and oxidative stress in muscle cells. The use of low levels of graphene oxide does not adversely affect muscle cells, reducing the levels of most proteins, including pro-inflammatory proteins. It can be assumed that GO may support anti-inflammatory therapy in muscles by scavenging proteins that activate cytokine storm.

8.
Nanoscale ; 15(46): 18639-18659, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37975795

RESUMO

Nanostructuring is a process involving surface manipulation at the nanometric level, which improves the mechanical and biological properties of biomaterials. Specifically, it affects the mechanotransductive perception of the microenvironment of cells. Mechanical force conversion into an electrical or chemical signal contributes to the induction of a specific cellular response. The relationship between the cells and growth surface induces a biointerface-modifying cytophysiology and consequently a therapeutic effect. In this study, we present the fabrication of graphene oxide (GO)-based nanofilms decorated with metallic nanoparticles (NPs) as potential coatings for biomaterials. Our investigation showed the effect of decorating GO with metallic NPs for the modification of the physicochemical properties of nanostructures in the form of nanoflakes and nanofilms. A comprehensive biocompatibility screening panel revealed no disturbance in the metabolic activity of human fibroblasts (HFFF2) and bone marrow stroma cells (HS-5) cultivated on the GO nanofilms decorated with gold and copper NPs, whereas a significant cytotoxic effect of the GO nanocomplex decorated with silver NPs was demonstrated. The GO nanofilm decorated with gold NPs beneficially managed early cell adhesion as a result of the transient upregulation of α1ß5 integrin expression, acceleration of cellspreading, and formation of elongated filopodia. Additionally, the cells, sensing the substrate derived from the nanocomplex enriched with gold NPs, showed reduced elasticity and altered levels of vimentin expression. In the future, GO nanocomplexes decorated with gold NPs can be incorporated in the structure of architecturally designed biomimetic biomaterials as biocompatible nanostructuring agents with proadhesive properties.


Assuntos
Grafite , Nanopartículas Metálicas , Nanoestruturas , Humanos , Adesão Celular , Nanoestruturas/química , Nanopartículas Metálicas/química , Grafite/farmacologia , Grafite/química , Ouro/farmacologia , Ouro/química , Materiais Biocompatíveis/farmacologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-37824053

RESUMO

The increasing emergence of antibiotic-resistant bacteria and the need to reduce the use of antibiotics call for the development of safe alternatives, such as silver nanoparticles. However, their potential cytotoxic effect needs to be addressed. Graphene oxide provides a large platform that can increase the effectiveness and safety of silver nanoparticles. Graphene oxide and silver nanoparticles complex applied as a part of an innovative material might have direct contact with human tissues, such as skin, or might be inhaled from aerosol or exfoliated pieces of the complex. Thereby, the safety of the prepared complex has to be evaluated carefully, employing a range of methods. We demonstrated the high cytocompatibility of graphene oxide and the graphene oxide-silver nanoparticles complex toward human cell lines, fetal foreskin fibroblasts (HFFF2), and lung epithelial cells (A549). The supporting platform of graphene oxide also neutralized the slight toxicity of bare silver nanoparticles. Finally, in studies on Staphylococcus aureus and Pseudomonas aeruginosa, the number of bacteria reduction was observed after incubation with silver nanoparticles and the graphene oxide-silver nanoparticles complex. Our findings confirm the possibility of employing a graphene oxide-silver nanoparticles complex as a safe agent with reduced silver nanoparticles' cytotoxicity and antibacterial properties.

10.
Materials (Basel) ; 16(22)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38005058

RESUMO

The properties of silk make it a promising material for medical applications, both in human and veterinary medicine. Its predominant amino acids, glycine and alanine, exhibit low chemical reactivity, reducing the risk of graft rejection, a notable advantage over most synthetic polymers. Hence, silk is increasingly used as a material for 3D printing in biomedicine. It can be used to build cell scaffolding with the desired cytocompatibility and biodegradability. In combination with gelatine, silk can be used in the treatment of arthritis, and as a hydrogel, to regenerate chondrocytes and mesenchymal cells. When combined with gelatine and collagen, it can also make skin grafts and regenerate the integumentary system. In the treatment of bone tissue, it can be used in combination with polylactic acid and hydroxyapatite to produce bone clips having good mechanical properties and high immunological tolerance. Furthermore, silk can provide a good microenvironment for the proliferation of bone marrow stem cells. Moreover, research is underway to produce artificial blood vessels using silk in combination with glycidyl methacrylate. Silk vascular grafts have demonstrated a high degree of patency and a satisfactory degree of endothelial cells coverage.

11.
Int J Food Sci Nutr ; 63(3): 296-302, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21999600

RESUMO

The aim of this research was to analyse the quality of the lipid fraction extracted from commercially available cookies intended for infants. The composition, fatty acid distribution and oxidative stability of fats, interpreted as the resistance of fats against autooxidation, were studied. In addition, the kinetic parameters of the oxidation process, such as activation energies (E(a)), pre-exponential factors (Z) and reaction rate constants (k) for fat oxidation under the differential scanning calorimetry tests conditions were calculated using the Ozawa-Flynn-Wall method and the Arrhenius equation. The distribution of fatty acids in the tested cookies is similar to that present in most of infant formulas, but differs significantly from that in human milk. Based on the results obtained, high oxidative stability of tested fats can be observed. The E(a) values ranged from 86.22 to 116.13 kJ/mol; Z from 1.95 × 10(9) to 1.05 × 10(13); and k values ranged from 5.70 × 10(- 4) min(- 1) at 100°C to 2.12 × 10(- 1) min(- 1) at 170°C.


Assuntos
Alimentos Infantis/análise , Lipídeos/química , Triglicerídeos/química , Varredura Diferencial de Calorimetria , Humanos , Lactente , Cinética , Oxirredução
12.
Polymers (Basel) ; 14(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35631843

RESUMO

Every application of a substance results from the macroscopic property of the substance that is related to the substance's microscopic structure. For example, the forged park gate in your city was produced thanks to the malleability and ductility of metals, which are related to the ability of shifting of layers of metal cations, while fire extinguishing powders use the high boiling point of compounds related to their regular ionic and covalent structures. This also applies to polymers. The purpose of this review is to summarise and present information on selected food-related biopolymers, with special attention on their respective structures, related properties, and resultant applications. Moreover, this paper also highlights how the treatment method used affects the structure, properties, and, hence, applications of some polysaccharides. Despite a strong focus on food-related biopolymers, this review is addressed to a broad community of both material engineers and food researchers.

13.
Lab Anim ; 56(3): 225-234, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34565205

RESUMO

The main microbial contaminants of rooms in which laboratory rodents are housed are bacteria and fungi. Restriction of microbial growth to below threshold levels requires the application of various sophisticated antimicrobial techniques that must be effective and safe for the animals. Some of the most commonly used techniques, including chemical disinfection, ventilation, filtration, sterilization and radiation, are not always sufficiently effective. The aim of the current study was to evaluate the efficacy of a modern technique (i.e. radiant catalytic ionization (RCI)) on the microbiological status of an animal care facility, and the health of the mice housed therein. The experiment, conducted over seven days, compared an experimental room with an RCI system permanently turned on with a negative control room. At the completion of the experiment, the number of bacteria in the RCI room air and on its walls was lower than that in the control room (p < 0.01 in both cases). Values of the basic prooxidative parameter, thiobarbituric acid reactive substances concentration, in tissues of mice from the RCI room were within allowed boundaries. Hence, application of an RCI system proved to be an ideal technique to ensure high hygienic standards in animal rooms without any adverse effects on the animals housed therein.


Assuntos
Fungos , Roedores , Animais , Bactérias , Desinfecção/métodos , Camundongos , Ventilação
14.
Polymers (Basel) ; 14(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36559918

RESUMO

The growing perspective of running out of crude oil followed by increasing prices for all crude oil-based materials, e.g., crude oil-based polymers, which have a huge number of practical applications but are usually neither biodegradable nor environmentally friendly, has resulted in searching for their substitutes-namely, bio-based polymers. Currently, both these types of polymers are used in practice worldwide. Owing to the advantages and disadvantages occurring among plastics with different origin, in this current review data on selected popular crude oil-based and bio-based polymers has been collected in order to compare their practical applications resulting from their composition, chemical structure, and related physical and chemical properties. The main goal is to compare polymers in pairs, which have the same or similar practical applications, regardless of different origin and composition. It has been proven that many crude oil-based polymers can be effectively replaced by bio-based polymers without significant loss of properties that ensure practical applications. Additionally, biopolymers have higher potential than crude oil-based polymers in many modern applications. It is concluded that the future of polymers will belong to bio-based rather than crude oil-based polymers.

15.
Nanotechnol Sci Appl ; 14: 115-137, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511890

RESUMO

PURPOSE: Surgical resection of hepatocellular carcinoma can be associated with recurrence resulting from the degeneration of residual volume of the liver. The objective was to assess the possibility of using a biocompatible nanofilm, made of a colloid of diamond nanoparticles (nfND), to fill the side after tumour resection and optimize its contact with proliferating liver cells, minimizing their cancerous transformation. METHODS: HepG2 and C3A liver cancer cells and HS-5 non-cancer cells were used. An aqueous colloid of diamond nanoparticles, which covered the cell culture plate, was used to create the nanofilm. The roughness of the resulting nanofilm was measured by atomic force microscopy. Mitochondrial activity and cell proliferation were measured by XTT and BrdU assays. Cell morphology and a scratch test were used to evaluate the invasiveness of cells. Flow cytometry determined the number of cells within the cell cycle. Protein expression in was measured by mass spectrometry. RESULTS: The nfND created a surface with increased roughness and exposed oxygen groups compared with a standard plate. All cell lines were prone to settling on the nanofilm, but cancer cells formed more relaxed clusters. The surface compatibility was dependent on the cell type and decreased in the order C3A >HepG2 >HS-5. The invasion was reduced in cancer lines with the greatest effect on the C3A line, reducing proliferation and increasing the G2/M cell population. Among the proteins with altered expression, membrane and nuclear proteins dominated. CONCLUSION: In vitro studies demonstrated the antiproliferative properties of nfND against C3A liver cancer cells. At the same time, the need to personalize potential therapy was indicated due to the differential protein synthetic responses in C3A vs HepG2 cells. We documented that nfND is a source of signals capable of normalizing the expression of many intracellular proteins involved in the transformation to non-cancerous cells.

16.
PeerJ ; 9: e10760, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33552740

RESUMO

BACKGROUND: Elaeagnus umbellata is a plant commonly used in traditional Asian medicine for its many health benefits and strong antioxidative activity. Its therapeutic potential is believed to be connected to its effect on fibroblasts. This study aimed to investigate E. umbellata methanol-acetone extract's (EUE) defense against hydrogen peroxide (H2O2)-induced fibroblast damage. METHODS: Because the main biologically active compounds of E. umbellata are water-insoluble, we evaluated the effects of methanol-acetone fruit extracts using liquid chromatography (for ascorbic acid and beta-carotene) and spectrophotometry (for lycopene and total phenolics). The extract's antioxidative activity was measured using DPPH radical inhibition, and EUE's effect on human fibroblasts was also evaluated. We assessed the metabolic activity and apoptosis of HFFF-2 fibroblasts exposed to EUE and/or H2O2using the XTT test and flow cytometry, respectively. Superoxide dismutase activity and reactive oxygen species (ROS) production were evaluated using colorimetric and fluorometric assays, respectively. We measured pro-inflammatory cytokine (MIF, fractalkine, MCP-4, BLC, GCP-2, NAP-2, Eotaxin-2, and Eotaxin-3) expression in HFFF-2 cells using immunocytochemistry. RESULT: The extract increased HFFF-2 cell proliferation and reduced cell death caused by H2O2-induced stress. H2O2-treated fibroblasts had greater ROS production than cells treated with both H2O2 and EUE. Additionally, the group treated with H2O2 alone showed higher pro-inflammatory cytokine (MIF, MCP-4, NAP-2, Eotaxin-2, and Eotaxin-3) expression. CONCLUSION: EUE protected human fibroblasts from H2O2-induced oxidative stress and reduced the fibroblast-mediated inflammatory response triggered by ROS.

17.
Materials (Basel) ; 13(15)2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32756412

RESUMO

The interest around the graphene family of materials is constantly growing due to their potential application in biomedical fields. The effect of graphene and its derivatives on cells varies amongst studies depending on the cell and tissue type. Since the toxicity against non-adherent cell lines has barely been studied, we investigated the effect of graphene and two different graphene oxides against four multiple myeloma cell lines, namely KMS-12-BM, H929, U226, and MM.1S, as well as two non-Hodgkin lymphoma cells lines, namely KARPAS299 and DOHH-2. We performed two types of viability assays, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide conversion) and ATP (adenosine triphosphate detection), flow cytometry analysis of apoptosis induction and cell cycle, cell morphology, and direct interaction analysis using two approaches-visualization of living cells by two different systems, and visualization of fixed and dyed cells. Our results revealed that graphene and graphene oxides exhibit low to moderate cytotoxicity against cells, despite visible interaction between the cells and graphene oxide. This creates possibilities for the application of the selected graphene materials for drug delivery systems or theragnostics in hematological malignancies; however, further detailed studies are necessary to explain the nature of interactions between the cells and the materials.

18.
Food Chem ; 295: 172-179, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174747

RESUMO

The effects of 10 and 20 days of fermentation followed by freeze-drying on the vitamin C and fatty acids contents, chemical conversions and overall chemical composition of Jerusalem artichoke were studied. Fermentation between the 10th and 20th days increased content of all saturated fatty acids and two of the four unsaturated fatty acids. The only fatty acid content that decreased was that of C18:1 cis 9 acid, which was suggested to be converted to other fatty acids. The experimental data, which were supported by energetical feasibility, suggested the reaction pathways of the mutual conversions of fatty acids and confirmed the decreased vitamin C content during fermentation. Discriminant modelling of the spectral data successfully distinguished the fresh, 10 days and 20 days fermented samples. The correlation of the spectral and reference data allowed to construct reference models for predicting the content of vitamin C and C18:1 cis 9 fatty acid.


Assuntos
Ácido Ascórbico/metabolismo , Ácidos Graxos/metabolismo , Helianthus/química , Silagem , Ácido Ascórbico/análise , Ácidos Graxos/análise , Fermentação , Análise de Alimentos/estatística & dados numéricos , Liofilização , Helianthus/metabolismo , Modelos Estatísticos , Silagem/análise , Espectrofotometria Infravermelho/estatística & dados numéricos
19.
Int J Anal Chem ; 2019: 5417962, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31186645

RESUMO

The central point of current investigations was the first time ever synthesis of modern substitutes of human milk fat followed by versatile evaluation of their oxidative properties. The enzymatic interesterification conducted at 70°C for 2, 4, and 6 hours, respectively, with milk thistle oil and lard blend as starting reactants was catalyzed by 1,3-specific lipase Lipozyme RM IM, obtained from Rhizomucor miehei. Pressure Differential Scanning Calorimetry (PDSC) and Fourier Transform Infrared Spectroscopy (FT-IR) were applied to evaluate quality of products formed. Although PDSC curves showed lower oxidative stability of newly synthesized fats as compared to both starting materials separately, they can be considered adequate substitutes of human fat milk fat, as distribution of fatty acids in triacylglycerol molecules of substitutes obtained is much alike human milk fat itself, as resulted from analysis of GC data collected. Obvious changes in chemical structure of fats occurring during interesterification resulted in specific alterations in IR spectra of processed materials. Spectral data accompanied by PLS technique were successfully used for accurate determination of oxidative stability of new fats through indirect procedure, i.e., IR-PDSC-reference analysis of induction time. Additionally IR data exclusively, i.e., without any reference data, occurred powerfully in discrimination of human fat milk substitutes obtained.

20.
J Anal Methods Chem ; 2017: 4315678, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28243483

RESUMO

Samples of wheat, spelt, rye, and triticale flours produced by different Polish mills were studied by both classic chemical methods and FT-IR MIR spectroscopy. An attempt was made to statistically correlate FT-IR spectral data with reference data with regard to content of various components, for example, proteins, fats, ash, and fatty acids as well as properties such as moisture, falling number, and energetic value. This correlation resulted in calibrated and validated statistical models for versatile evaluation of unknown flour samples. The calibration data set was used to construct calibration models with use of the CSR and the PLS with the leave one-out, cross-validation techniques. The calibrated models were validated with a validation data set. The results obtained confirmed that application of statistical models based on MIR spectral data is a robust, accurate, precise, rapid, inexpensive, and convenient methodology for determination of flour characteristics, as well as for detection of content of selected flour ingredients. The obtained models' characteristics were as follows: R2 = 0.97, PRESS = 2.14; R2 = 0.96, PRESS = 0.69; R2 = 0.95, PRESS = 1.27; R2 = 0.94, PRESS = 0.76, for content of proteins, lipids, ash, and moisture level, respectively. Best results of CSR models were obtained for protein, ash, and crude fat (R2 = 0.86; 0.82; and 0.78, resp.).

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