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1.
Chemistry ; 29(29): e202300214, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-36872887

RESUMO

The C-H functionalization of indole heterocycles constitutes a key strategy to leverage the synthesis of endogenous signaling molecules such as tryptamine or tryptophol. Herein, we report on the photocatalytic reaction of ethyl diazoacetate with indole, which shows an unusual solvent dependency. While C2-functionalization occurs under protic conditions, the use of aprotic solvents leads to a complete reversal of selectivity and exclusive C3-functionalization occurs. To rationalize for this unexpected reactivity switch, we have conducted detailed theoretical and experimental studies, which suggest the participation of a triplet carbene intermediate that undergoes initial C2-functionalization. A distinct cationic [1,2]-alkyl radical migration then leads to formation of C3-functionalized indole. We conclude with the application of this photocatalytic reaction to access oxidized tryptophol derivatives including gram-scale synthesis and derivatization reactions.

2.
Int J Mol Sci ; 24(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36834968

RESUMO

In this article, we present research on the influence of erbium ions on the structure and magneto-optical properties of 70TeO2-5XO-10P2O5-10ZnO-5PbF2 (X = Pb, Bi, Ti) tellurite glass systems. Structural changes occurring in the glasses during doping with erbium ions were investigated using positron annihilation lifetime spectroscopy (PALS) and Raman spectroscopy. The X-ray diffraction (XRD) method was used to confirm the amorphous structure of the investigated samples. Based on the Faraday effect measurements and calculated values of Verdet constant, the magneto-optical properties of the glasses were determined.


Assuntos
Érbio , Chumbo , Érbio/química , Titânio , Análise Espectral Raman , Íons
3.
Int J Mol Sci ; 24(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36613931

RESUMO

The aim of this work has been to study the possible degradation path of BPA under the Fenton reaction, namely to determine the energetically favorable intermediate products and to compare the cytotoxicity of BPA and its intermediate products of degradation. The DFT calculations of the Gibbs free energy at M06-2X/6-311G(d,p) level of theory showed that the formation of hydroquinone was the most energetically favorable path in a water environment. To explore the cytotoxicity the erythrocytes were incubated with BPA and three intermediate products of its degradation, i.e., phenol, hydroquinone and 4-isopropylphenol, in the concentrations 5-200 µg/mL, for 1, 4 and 24 h. BPA induced the strongest hemolytic changes in erythrocytes, followed by hydroquinone, phenol and 4-isopropylphenol. In the presence of hydroquinone, the highest level of RONS was observed, whereas BPA had the weakest effect on RONS generation. In addition, hydroquinone decreased the level of GSH the most. Generally, our results suggest that a preferable BPA degradation path under a Fenton reaction should be controlled in order to avoid the formation of hydroquinone. This is applicable to the degradation of BPA during waste water treatment and during chemical degradation in sea water.


Assuntos
Hidroquinonas , Poluentes Químicos da Água , Humanos , Hidroquinonas/toxicidade , Fenóis/farmacologia , Eritrócitos/metabolismo , Compostos Benzidrílicos/farmacologia , Fenol/metabolismo , Poluentes Químicos da Água/metabolismo
4.
Molecules ; 28(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36615453

RESUMO

Lavender is a valuable medicinal plant belonging to the Lamiaceae family. Currently 39 species are known, but only Lavandula angustifolia is a pharmacopoeial raw material. Lavender has a long history of medicinal use and mainly exhibits antioxidant, anti-inflammatory, sedative, antidepressant, spasmolytic, anticholinesterases, antifungal and antibacterial properties. Used internally, it relieves symptoms of mental stress and insomnia and supports digestion. Topical use of lavender in aromatherapy, neuralgia and antiseptics is also known. The constant interest in lavender, and in particular in Lavandula angustifolia, in the field of medicine and pharmacy is evidenced by the growing number of publications. In view of so many studies, it seems important to review traditional and modern extraction techniques that determine the chemical composition responsible for the antioxidant and anti-inflammatory effects of various extracts from the species of the Lavandula genus.


Assuntos
Lavandula , Óleos Voláteis , Lavandula/química , Antioxidantes/farmacologia , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Compostos Fitoquímicos/farmacologia , Anti-Inflamatórios/farmacologia , Óleos de Plantas
5.
Int J Mol Sci ; 22(8)2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33919556

RESUMO

Mechanochemical and in-solution synthesis of caffeine complexes with α-, ß-, and γ-cyclodextrins was optimized. It was found that short-duration, low-energy cogrinding, and evaporation (instead of freeze-drying) are effective methods for the formation and isolation of these complexes. The products obtained, their pure components, and their mixtures were examined by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), FT-IR and Raman spectroscopy. Moreover, molecular modeling provided an improved understanding of the association process between the guest and host molecules in these complexes. The complexes were found to exhibit high toxicity in zebrafish (Danio rerio) embryos, in contrast to pure caffeine and cyclodextrins at the same molar concentrations. HPLC measurements of the caffeine levels in zebrafish embryos showed that the observed cytotoxicity is not caused by an increased caffeine concentration in the body of the organism, as the concentrations are similar regardless of the administered caffeine form. Therefore, the observed high toxicity could be the result of the synergistic effect of caffeine and cyclodextrins.


Assuntos
Cafeína/química , Ciclodextrinas/química , Animais , Cafeína/farmacologia , Varredura Diferencial de Calorimetria , Ciclodextrinas/farmacologia , Sinergismo Farmacológico , Embrião não Mamífero/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Difração de Raios X , Peixe-Zebra
6.
Molecules ; 26(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806878

RESUMO

High-pressure homogenization (HPH) is one of the food-processing methods being tested for use in food preservation as an alternative to pasteurization. The effects of the HPH process on food can vary depending on the process parameters used and product characteristics. The study aimed to investigate the effect of pressure, the number of passes, and the inlet temperature of HPH processing on the quality of cloudy blackcurrant juice as an example of food rich in bioactive compounds. For this purpose, the HPH treatment (pressure of 50, 150, and 220 MPa; one, three, and five passes; inlet temperature at 4 and 20 °C) and the pasteurization of the juice were performed. Titratable acidity, pH, turbidity, anthocyanin, vitamin C, and total phenolics content, as well as colour, and antioxidant activity were measured. Heat treatment significantly decreased the quality of the juice. For processing of the juice, the best were the combinations of the following: one pass, the inlet temperature of 4 °C, any of the used pressures (50, 150, and 220 MPa); and one pass, the inlet temperature of 20 °C, and the pressure of 150 MPa. Vitamin C and anthocyanin degradation have been reported during the HPH. The multiple passes of the juice through the machine were only beneficial in increasing the antioxidant capacity but negatively affected the colour stability.


Assuntos
Antioxidantes/química , Manipulação de Alimentos , Sucos de Frutas e Vegetais , Frutas/química , Compostos Fitoquímicos/química , Ribes/química , Pressão
7.
Molecules ; 25(18)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899830

RESUMO

Aronia fruits contain many valuable components that are beneficial to human health. However, fruits are characterized by significant variations in chemical composition dependent on the growing conditions and harvesting period. Therefore, there is a need to formulate the extracts with a precisely defined content of health-promoting substances. Aronia dry extracts (ADE) were prepared from frozen pomace applying water extraction, followed by purification and spray-drying. Subsequently, the content of anthocyanins, phenolic acids, and polyphenols was determined. The high-quality chokeberry pomace enabled obtaining extracts with anthocyanin content much higher than the typical market standards. Moreover, it was found that the antioxidant capacity of aronia extracts exceeded those found in other fruit preparations. Antioxidant and free-radical scavenging properties were evaluated using a 2,2'-diphenyl-1-picrylhydrazyl using Electron Paramagnetic Resonance (EPR) spectroscopy (DPPH-EPR) test and Oxygen Radical Absorbance Capacity (ORAC) assay. The inhibition of lipid peroxidation and the level of inflammatory markers have been also investigated using lipopolysaccharide (LPS)-stimulated RAW 264 cells. It was revealed that ADE standardized to 25% of anthocyanins depresses the level of markers of inflammation and lipid peroxidation (Interleukin 1 beta (IL-1ß), tumor necrosis factor alpha (TNF-α), and malondialdehyde (MDA)) in in vitro conditions. Additionally, it was confirmed that ADE at all analyzed concentrations did not show any cytotoxic effect as demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.


Assuntos
Antocianinas/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Photinia/química , Extratos Vegetais/farmacologia , Água/química , Animais , Morte Celular/efeitos dos fármacos , Interleucina-1beta/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Malondialdeído/metabolismo , Camundongos , Células RAW 264.7 , Solubilidade , Fator de Necrose Tumoral alfa/metabolismo
8.
Anal Chem ; 91(17): 11306-11315, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31387347

RESUMO

Nuclear magnetic resonance spectroscopy (NMR) is a versatile tool of chemical analysis allowing one to determine structures of molecules with atomic resolution. Particularly informative are two-dimensional (2D) experiments that directly identify atoms coupled by chemical bonds or a through-space interaction. Thus, NMR could potentially be powerful tool to study reactions in situ and explain their mechanisms. Unfortunately, 2D NMR is very time-consuming and thus often cannot serve as a "snapshot" technique for in situ reaction monitoring. Particularly difficult is the case of spectra, in which resonance frequencies vary in the course of reaction. This leads to resolution and sensitivity loss, often hindering the detection of transient products. In this paper we introduce a novel approach to correct such nonstationary 2D NMR signals and raise the detection limits over 10 times. We demonstrate success of its application for studying the mechanism of the reaction of AgSO4-induced synthesis of diphenylmethane-type compounds. Several reactions occur in the studied mixture of benzene and toluene, all with rather low yield and leading to compounds with similar chemical shifts. Nevertheless, with the use of a proposed 2D NMR approach we were able to describe complex mechanisms of diphenylmethane formation involving AgSO4-induced toluene deprotonation and formation of benzyl carbocation, followed by nucleophilic attacks.


Assuntos
Benzeno/química , Compostos Benzidrílicos/síntese química , Espectroscopia de Ressonância Magnética , Prata/química , Sulfatos/química , Tolueno/química , Compostos Benzidrílicos/química
9.
J Am Chem Soc ; 138(47): 15451-15458, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27933929

RESUMO

Metalloporphyrins not only are vital in biological systems but also are valuable catalysts in organic synthesis. On the other hand, catalytic properties of free base porphyrins have been less explored. They are mostly known as efficient photosensitizers for the generation of singlet oxygen via photoinduced energy transfer processes, but under light irradiation, they can also participate in electron transfer processes. Indeed, we have found that free base tetraphenylporphyrin (H2TPP) is an efficient photoredox catalyst for the reaction of aldehydes with diazo compounds leading to α-alkylated derivatives. The performance of a porphyrin catalyst can be optimized by tailoring various substituents at the periphery of the macrocycle at both the ß and meso positions. This allows for the fine tuning of their optical and electrochemical properties and hence their catalytic activity.

10.
J Oral Pathol Med ; 45(10): 753-757, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26876359

RESUMO

BACKGROUND: Oxidative DNA damage leads to abnormalities in endogenous cellular processes and constitutes a direct link between free radicals, antioxidants and squamous cell carcinoma (SCC). Oxygen radical absorbance capacity (ORAC) method is used to measure antioxidant capacity versus oxygen free radicals. There is no report on the application of ORAC to evaluate salivary antioxidant capacity in patients with head and neck SCC. This study investigated the relation between total antioxidant capacity of saliva, measured with ORAC method, and the incidence, location, size and histopathological grading of SCC. METHODS: Salivary antioxidant capacity was assessed in 30 male and female patients with histopathologically confirmed oral and laryngeal SCC. Histopathological grading of SCC was based on WHO classification. RESULTS: Mean ORAC in patients with SCC was higher than the mean value in the control group. Statistically significant difference was observed in the study group versus the control group. No significant differences were observed for ORAC values in relation to histopathological grading, tumour size and spread to lymph nodes. CONCLUSIONS: The obtained results can advocate local compensatory mechanism in saliva in response to increased oxidative stress associated with primary tumour. ORAC can become an additional factor in head and neck SCC prognosis, but further investigation is required.


Assuntos
Antioxidantes/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Saliva/metabolismo , Idoso , Antioxidantes/química , Carcinoma de Células Escamosas/genética , Dano ao DNA , Feminino , Radicais Livres/química , Radicais Livres/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Humanos , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Oxirredução , Capacidade de Absorbância de Radicais de Oxigênio , Saliva/química , Carcinoma de Células Escamosas de Cabeça e Pescoço
11.
Biophys J ; 109(9): 1917-24, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26536268

RESUMO

Influenza virus delivers its genome to the host cytoplasm via a process of membrane fusion mediated by the viral hemagglutinin protein. Optimal fusion likely requires multiple hemagglutinin trimers, so the spatial distribution of hemagglutinin on the viral envelope may influence fusion mechanism. We have previously shown that moderate depletion of cholesterol from the influenza viral envelope accelerates fusion kinetics even though it decreases fusion efficiency, both in a reversible manner. Here, we use electron cryo-microscopy to measure how the hemagglutinin lateral density in the viral envelope changes with cholesterol extraction. We extract this information by measuring the radial distribution function of electron density in >4000 viral images per sample, assigning hemagglutinin density by comparing images with and without anti-HA Fab bound. On average, hemagglutinin trimers move closer together: we estimate that the typical trimer-trimer spacing reduces from 94 to 84 Å when ∼90% of cholesterol is removed from the viral membrane. Upon restoration of viral envelope cholesterol, this spacing once again expands. This finding can qualitatively explain the observed changes to fusion kinetics: contemporary models from single-virus microscopy are that fusion requires the engagement of several hemagglutinin trimers in close proximity. If removing cholesterol increases the lateral density of hemagglutinin, this should result in an increase in the rate of fusion.


Assuntos
Colesterol/metabolismo , Hemaglutininas/metabolismo , Orthomyxoviridae/metabolismo , Proteínas do Envelope Viral/metabolismo , Vírion/metabolismo , Animais , Microscopia Crioeletrônica , Cães , Células Madin Darby de Rim Canino , Orthomyxoviridae/ultraestrutura , Multimerização Proteica , Vírion/ultraestrutura
12.
Acta Pol Pharm ; 72(5): 877-87, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26665393

RESUMO

Oxidative stress (OS), defined as a disturbance in the balance between the production of reactive oxygen species (ROS) and antioxidant defenses, can result in the development of many serious diseases like diabetes or cancer. Moreover, the role of oxidative stress in the acceleration of the aging process is also confirmed. ROS are constantly produced in the natural biochemical processes, mainly during cellular respiration. Their enhanced production may be the result of e.g., an inappropriate diet high in saturated fats, low in fiber, fruits and vegetables, insufficient physical activity or smoking. To prevent oxidative stress, besides changes in life style, the additional supplementation of antioxidants is proposed. On the Polish market, the number of food supplements with declared antioxidant activity is still increasing. However, their antioxidant properties are rarely confirmed experimentally. The aim of our study was to determine the antioxidant potential of selected dietary supplements available on the market and recommended in chronic fatigue syndrome. The antioxidant potential was measured using four methods: FRAP, ORAC, HORAC, EPR/DPPH. Moreover, the content of polyphenols in the dietary supplements was also determined.


Assuntos
Antioxidantes/farmacologia , Suplementos Nutricionais/análise , Polifenóis/análise , Polifenóis/farmacologia
13.
J Sci Food Agric ; 94(2): 246-55, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23712445

RESUMO

BACKGROUND: Herbhoneys, relatively new bee products, are expected to have interesting medicinal properties. However, there is still a lack of data concerning their composition and antioxidant properties. ¹H and ¹³C NMR spectroscopy coupled with chemometric analysis (PCA and PLS-DA) and antioxidant assays (DPPH-ESR and ORAC-FL) were used to study 25 samples of Polish herbhoneys and honeys. RESULTS: Antioxidant activity varied among the samples. The best properties were exhibited by cocoa and instant coffee herbhoneys. The contents of total polyphenols and total carotenoids in the studied samples were found to be 70-1340 mg GAE kg⁻¹ and 0-28.05 mg kg⁻¹ respectively. No significant differences between herbhoney and honey samples were found in their sugar profiles. The PCA of ¹³C NMR spectra of the samples in DMSO-d6 resulted in sample clustering due to sucrose content. CONCLUSION: Herbhoneys have similar antioxidant properties to traditional honeys, being therefore of equal nutritional value. There was a noticeable influence of the extract concentration on the observed antioxidant effect. For samples with high antioxidant activity, polyphenols were responsible for the observed effect. Sample clustering due to sucrose content in the NMR-PCA study allowed effortless detection of adulteration.


Assuntos
Antioxidantes/farmacologia , Carotenoides/farmacologia , Mel/análise , Valor Nutritivo , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Sacarose/análise , Animais , Abelhas , Compostos de Bifenilo/metabolismo , Carotenoides/análise , Dieta , Humanos , Espectroscopia de Ressonância Magnética/métodos , Picratos/metabolismo , Polifenóis/análise
14.
Antioxidants (Basel) ; 13(4)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38671910

RESUMO

Aronia (chokeberry, Aronia melanocarpa) is a valuable fruit that combines the health benefits of green tea and red wine and is gaining popularity worldwide. Aronia has a unique chemical composition with strong antioxidant properties, including anthocyanins and chlorogenic acids (CGAs). However, it remains unclear which specific compounds or groups are primarily responsible for the antioxidant properties of chokeberry. Therefore, an analysis of the antioxidant properties of aronia berries based on geographical region and their variability during ripening (from green to frostbitten fruit) was conducted. The fruits were collected from three locations for two years. The aim of our work was to identify the compounds responsible for the antioxidant properties of aronia berry extracts by using chemometric methods. The analyses of anthocyanins and CGAs were performed using HPLC-DAD, and the antioxidant capacity was assessed by FRAP and DPPH methods. The PCA analysis also considered variations in temperature and precipitation. The chemometric analysis revealed a strong correlation between radical-scavenging properties and the content levels of chlorogenic acids. The results obtained in this study show that unripe green chokeberry fruits exhibit the highest antioxidant properties, which can be attributed to the high content of CGAs at this stage.

15.
JPEN J Parenter Enteral Nutr ; 47(5): 646-653, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37154582

RESUMO

BACKGROUND AND AIM: Lipid peroxidation in parenteral nutrition mixtures is still a challenge. We aimed to evaluate the effect of two different amino acid solutions used in different clinical situations on lipid peroxidation of three different lipid emulsions (Intralipid, ClinOleic, and SMOFlipid) in all-in-one admixtures during 24 h of simulated infusion. The selected amino acid solutions included one used in stable patients and one used in renal insufficiency (Aminomel10E and Nephrotect, respectively). METHODS: Eighteen all-in-one admixtures were prepared. The simulated infusion with light protection was conducted straight after the preparation for 24 h at room temperature. The lipid peroxidation process was evaluated in all-in-one admixtures and the original lipid emulsion by determining the malondialdehyde levels (high-performance liquid chromatography) and conjugated dienes and trienes (ultraviolet-visible spectrophotometry). RESULTS: Malondialdehyde in the original packaging was lower in SMOFlipid (9 µM) compared with Intralipid (27 µM, P = 0.0003) and ClinOleic (25 µM, P = 0.0001). During simulated infusion, ClinOleic showed a significantly lower rate of lipid peroxidation (26% decrease in aldehyde levels) in comparison with Intralipid and SMOFlipid (up to 39% and 31% increase in aldehyde levels, respectively) when the admixture was based on Aminomel10E. In admixtures based on Nephrotect, ClinOleic, and SMOFlipid showed better oxidative stability in comparison with Intralipid. Admixtures based on Nephrotect and Intralipid had higher levels of primary lipid peroxidation products than those based on ClinOleic (P = 0.030) or SMOFlipid (P = 0.071, not significant). CONCLUSIONS: Amino acid solutions influence the rate of lipid peroxidation. The observation should be confirmed in larger studies with different amino acid solutions.


Assuntos
Aminoácidos , Emulsões Gordurosas Intravenosas , Humanos , Emulsões , Emulsões Gordurosas Intravenosas/química , Aminoácidos/metabolismo , Estresse Oxidativo , Malondialdeído , Aldeídos
16.
Antioxidants (Basel) ; 11(4)2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35453396

RESUMO

Lavender is a valuable perennial plant from the Lamiaceae family. It is grown mainly for its essential oil, but it also contains polar bioactive compounds such as polyphenols and coumarins. Their level depends on the species, cultivars, geographical origin, climatic conditions, harvest time and extraction method. The authors investigated the effect of several extraction procedures (maceration, decoction and ultrasound-assisted extraction) applied to three cultivars of Lavandula angustifolia (Betty's Blue, Elizabeth, Hidcote) and two cultivars of Lavandula x intermedia (Grosso, Gros Bleu) on the yield of the polyphenolic compounds and antioxidant activity. HPLC analysis showed the presence of rosmarinic acid (2.52-10.82 mg/g), ferulic acid glucoside (2.94-8.67 mg/g), caffeic acid (1.70-3.10 mg/g), morin (1.02-13.63 mg/g), coumarin (1.01-5.97 mg/g) and herniarin (1.05-8.02 mg/g). The content of phenolic acids and flavonoids was higher in lavender, while the content of coumarins was higher in lavandin in all types of extracts. The antioxidant activity was determined by DPPH-EPR assay for antiradical properties (104.58-206.77 µmol Trolox/g) and FRAP assay for reducing properties (79.21-203.06 µmol Trolox/g). The obtained results showed that the cultivar is the dominant factor differentiating the samples. Still, the extraction method plays an important role in the final bioactive substances content and antioxidant properties of obtained extracts.

17.
Free Radic Biol Med ; 183: 69-74, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35314357

RESUMO

EPR spectroscopy is a technique that provides direct information about free radicals in biological systems. So far, X-band EPR was seldomly used for in vivo studies as the small resonator size and high power used to detect EPR signals were unsuitable for living organisms. Here, we report new solutions which lift some limitations and make X-band EPR suitable for an in vivo detection of free radicals in zebrafish - a small laboratory animal that is often used as a model for various studies related to free radicals. We designed specially-shaped glass and quartz capillaries to ensure the zebrafish's safety during the experiments. The optimal EPR spectrometer parameters, safe for zebrafish embryos and sufficient to obtain EPR spectrum, were 4 scans by 20s, 100G sweep, and 0.8 mW power. Combining the specially-shaped capillary with a multi-harmonic analyzer for the EPR spectrometer allowed increasing the time up to 16 scans by 11s and lowering the power to 0.25 mW. As a proof of principle, we demonstrate the detection of melanin radicals and the 5-DSA spin probe in zebrafish larvae. As fish survive the EPR scans, the possibility of performing multiple measurements of free radicals in living zebrafish offers new tools for studies aiming to understand redox biology and membrane-dependent functions in both health and disease.


Assuntos
Melaninas , Peixe-Zebra , Animais , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Radicais Livres/química , Melaninas/química , Óxidos de Nitrogênio
18.
Int J Stem Cells ; 14(1): 33-46, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33122467

RESUMO

BACKGROUND AND OBJECTIVES: Despite significant improvement in the treatment of tendon injuries, the full tissue recovery is often not possible because of its limited ability to auto-repair. The transplantation of mesenchymal stromal cells (MSCs) is considered as a novel approach in the treatment of tendinopathies. The question about the optimal culture conditions remains open. In this study we aimed to investigate if serum reduction, L-ascorbic acid supplementation or a combination of both factors can induce tenogenic differentiation of human adipose-derived MSCs (ASCs). METHODS AND RESULTS: Human ASCs from 3 healthy donors were used in the study. The tested conditions were: 0.5 mM of ascorbic acid 2-phosphate (AA-2P), reduced serum content (2% FBS) or combination of these two factors. The combination of AA-2P and 2% FBS was the only experimental condition that caused a significant increase of the expression of all analyzed genes related to tenogenesis (SCLERAXIS, MOHAWK, COLLAGEN_1, COLLAGEN_3, DECORIN) in comparison to the untreated control (evaluated by RT-PCR, 5th day of experiment). Moreover, this treatment significantly increased the synthesis of SCLERAXIS, MOHAWK, COLLAGEN_1, COLLAGEN_3 proteins at the same time point (evaluated by Western blot method). Double immunocytochemical staining revealed that AA-2P significantly increased the extracellular deposition of both types of collagens. Semi-quantitative Electron Spin Resonance analysis of ascorbyl free radical revealed that AA-2P do not induce harmful transition metals-driven redox reactions in cell culture media. CONCLUSIONS: Obtained results justify the use of reduced content of serum with the addition of 0.5 mM of AA-2P in tenogenic inducing media.

19.
Sci Rep ; 11(1): 3989, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597594

RESUMO

The polyphenol content and antioxidant capacity of hyperforin and hypericin-standardized H. perforatum L. extracts may vary due to the harvest time. In this work, ethanol and ethanol-water extracts of air-dried and lyophilized flowers of H. perforatum L., collected throughout a vegetation season in central Poland, were studied. Air-dried flowers extracts had higher polyphenol (371 mg GAE/g) and flavonoid (160 mg CAE/g) content, DPPH radical scavenging (1672 mg DPPH/g), ORAC (5214 µmol TE/g) and FRAP (2.54 mmol Fe2+/g) than lyophilized flowers extracts (238 mg GAE/g, 107 mg CAE/g, 1287 mg DPPH/g, 3313 µmol TE/g and 0.31 mmol Fe2+/g, respectively). Principal component analysis showed that the collection date influenced the flavonoid and polyphenol contents and FRAP of ethanol extracts, and DPPH and ORAC values of ethanol-water extracts. The ethanol extracts with the highest polyphenol and flavonoid content protected human erythrocytes against bisphenol A-induced damage. Both high field and benchtop NMR spectra of selected extracts, revealed differences in composition caused by extraction solvent and raw material collection date. Moreover, we have shown that benchtop NMR can be used to detect the compositional variation of extracts if the assignment of signals is done previously.


Assuntos
Antioxidantes/química , Flavonoides/química , Flores/química , Hypericum/química , Extratos Vegetais/química , Polifenóis/química , Antracenos/química , Antioxidantes/farmacologia , Compostos Benzidrílicos/química , Etanol/química , Humanos , Perileno/análogos & derivados , Perileno/química , Fenóis/química , Floroglucinol/análogos & derivados , Floroglucinol/química , Extratos Vegetais/farmacologia , Polônia , Polifenóis/farmacologia , Análise de Componente Principal , Terpenos/química
20.
Foods ; 9(12)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302360

RESUMO

The development of functional beverages often requires a compromise between the palatability and high content of bio-active compounds. The purpose of this study was to elaborate on the fruit-herbal beverages with defined pro-health functions and evaluate their consumer acceptance. The beverages contained 80% of juices obtained from the fruits of aronia, rugosa rose, acerola, sea buckthorn, and cranberry. Each beverage was supplemented with different plant extracts which enhanced the designed functions of the beverage. The beverages were sweetened with sugar or with steviol glycosides, and were preserved by thermal pasteurization. The main groups of bio-active compounds and antioxidant capacity using ABTS, DPPH, and ORAC methods were analysed before and after pasteurization. The sensory acceptance was tested by 60 adult consumers who assessed the desirability of taste, odour, colour, and overall quality. Each beverage contained substantial amounts of polyphenols, including anthocyanins; rosehip-acerola and sea buckthorn beverages were also sources of vitamin C and carotenoids. All these components were stable under thermal treatment. Rosehip-acerola beverages had the highest antioxidant capacity, which was measured using all three methods exhibited. The highest level of consumer acceptance and willingness to purchase went to aronia beverages, while the sea buckthorn gained the lowest. There was no significant difference between the acceptance of beverages sweetened with sugar and stevia. Women and the 25- to 34-year-old consumer group rated the overall acceptability of the beverages slightly higher, although this was not reflected in their inclination to buy them. Attitude toward proper body mass and health had no influence on overall acceptance and willingness to complete the purchases. The main motivation for purchasing the functional beverages was their sensory acceptance, even if the consumers were informed of their potential health benefits.

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