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31.
Magdalena Kurdziel Elżbieta Szczepaniec-Cięciak Barbara Dąbrowska Wojciech Nitek Katarzyna Paliś Edyta Ślusarska 《Journal of solution chemistry》2003,32(7):601-615
The solubilities of solid 2,3-dimethylbutane and cyclopentene in liquid argon at a temperature of 87.3 K and in liquid nitrogen at 77.4 K have been measured by the filtration method. The hydrocarbon contents in solutions were determined using gas chromatography. GC–MS was used to identify impurities in solutes. The experimental value of the mole fraction solubility of solid 2,3-dimethyl-butane in liquid argon at 87.3 K is (8.26 ± 1.60) × 10–6 and (2.77 ± 0.94) × 10–8 in liquid nitrogen at 77.4 K. The experimental value of the mole fraction solubility of solid cyclopentene in liquid argon at 87.3 K is (5.11 ± 0.44) × 10–6 and (4.60 ± 0.76) × 10–8 in liquid nitrogen at 77.4 K. The Preston–Prausnitz method was used for calculation of the solubilities of solid hydrocarbons in liquid argon in the temperature range 84.0–110.0 K and in liquid nitrogen from 64.0 to 90.0 K. The solvent–solute interaction parameters l
12 were also calculated. At 90.0 K liquid argon is a better solvent for investigated solid hydrocarbons than is liquid nitrogen. 相似文献
32.
Miguel F. Braa Jos M. Castellano Maria L. Lpez Rodriguez Magdalena Glvez Manuel R. Amil Enrique Rubio 《Journal of heterocyclic chemistry》1987,24(2):369-371
Hydrolysis of N,N'-diacyl-1,2-di(4-pyridyl)ethylenediamines 1 in aqueous sulfuric acid gave the corresponding imidazolines 3. 1,2-Di-(4-pyridyl)ethylenediamine 2 was prepared in 61 % yield by treating N,N'-di-t-butyl-oxycarbonyl-1,2-di(4-pyridyl)ethylenediamine 4 with trifluoroacetic acid or in 94% yield by the hydrolysis under basic conditions of N,N'-diphthaloylglycyl-1,2-di(4-pyridy)ethylenediamine 13. 相似文献
33.
Reaction of 3-methoxycarbonyl-2-methyl- or 3-dimethoxyphosphoryl-2-methyl-substituted 4-oxo-4H-chromones 1 with N-methylhydrazine resulted in the formation of isomeric, highly substituted pyrazoles 4 (major products) and 5 (minor products). Intramolecular transesterification of 4 and 5 under basic conditions led, respectively, to tricyclic derivatives 7 and 8. The structures of pyrazoles 4a (dimethyl 2-methyl-4-oxo-4H-chromen-3-yl-phosphonate) and 4b (methyl 4-oxo-2-methyl-4H-chromene-3-carboxylate) were confirmed by X-ray crystallography. Pyrazoles 4a and 4b were used as ligands (L) in the formation of ML2Cl2 complexes with platinum(II) or palladium(II) metal ions (M). Potassium tetrachloroplatinate(II), used as the metal ion reagent, gave both trans-[Pt(4a)2Cl2] and cis-[Pt(4a)2Cl2], complexes with ligand 4a, and only cis-[Pt(4b)2Cl2] isomer with ligand 4b. Palladium complexes were obtained by the reaction of bis(benzonitrile)dichloropalladium(II) with the test ligands. trans-[Pd(4a)2Cl2] and trans-[Pd(4b)2Cl2] were the exclusive products of these reactions. The structures of all the complexes were confirmed by IR, 1H NMR and FAB MS spectral analysis, elemental analysis and Kurnakov tests. 相似文献
34.
Marcin Feldo Magdalena Wjciak Aleksandra Ziemlewska Sawomir Dresler Ireneusz Sowa 《Molecules (Basel, Switzerland)》2022,27(13)
Diosmin is widely used as a venoactive drug in the pharmacological treatment of chronic venous disorders. It exerts a strong protective effect on blood vessels via an increase in the elasticity of vessel walls and reduces the permeability of capillary walls, thereby producing an anti-edematous effect. In this paper, we investigated the effectiveness of diosmin and diosmetin in modulating the level of proinflammatory factors in human skin fibroblasts treated with lipopolysaccharide (LPS). Two variants of the experiments were performed: the flavonoid was added 2 h prior to or 24 h after LPS stimulation. Our study revealed that both flavonoids reduced the levels of IL-6 and Il-1β as well as COX-2 and PGE2 but had no impact on IL-10. However, the addition of the compounds prior to the LPS addition was more effective. Moreover, diosmetin modulated the proinflammatory factors more strongly than diosmin. Our investigations also showed that both flavonoids were potent inhibitors of elastase and collagenase activity, and no differences between the glycoside and aglycone forms were observed. 相似文献
35.
Magdalena
widro-Pito Alicja Chromiec Marcin Zawadzki Renata Wietecha-Posuszny 《Molecules (Basel, Switzerland)》2022,27(13)
The present investigation utilised the quick and easy SPME/LC-MS method to determine selected narcotic substances and their metabolites in whole blood. The study included qualitative analysis and validation of the method. Analytes were determined in the linearity range of 25–300 ng/mL. The precision during and between days (in general CV < 13.41%), and the LOD which results in between 0.36 and 11.08 ng/mL, and the LOQ between 1.20 and 36.90 ng/mL were investigated. The validation results obtained, as well as the results of subsequent in-laboratory tests, confirmed the applicability of the method in the analysis of blood samples. An attempt to apply the method to the analysis of bone marrow samples has yielded promising results; however, more detailed studies are needed in this area. 相似文献
36.
Karolina Syrek Monika Sotys-Mrz Kinga Pawlik Magdalena Gurgul Grzegorz D. Sulka 《Molecules (Basel, Switzerland)》2022,27(15)
In this work, we present a systematic study on the influence of Cu2+ ion concentration in the impregnation solution on the morphology, structure, optical, semiconducting, and photoelectrochemical properties of anodic CuOx-TiO2 materials. Studied materials were prepared by immersion in solutions with different concentrations of (CH3COO)2Cu and subjected to air-annealing at 400 °C, 500 °C, or 600 °C for 2 h. The complex characterization of all studied samples was performed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), reflectance measurements, Mott–Schottky analyses, and photocurrent measurements. It was found that band gap engineering based on coupling CuO with TiO2 (Eg~3.3 eV) is an effective strategy to increase the absorption in visible light due to band gap narrowing (CuOx-TiO2 materials had Eg~2.4 eV). Although the photoactivity of CuO-TiO2 materials decreased in the UV range due to the deposition of CuO on the TiO2 surface, in the Vis range increased up to 600 nm at the same time. 相似文献
37.
In this paper, the photochemistry of glyoxal–hydroxylamine (Gly–HA) complexes is studied using FTIR matrix isolation spectroscopy and ab initio calculations. The irradiation of the Gly–HA complexes with the filtered output of a mercury lamp (λ > 370 nm) leads to their photoconversion to hydroxyketene–hydroxylamine complexes and the formation of hydroxy(hydroxyamino)acetaldehyde with a hemiaminal structure. The first product is the result of a double hydrogen exchange reaction between the aldehyde group of Gly and the amino or hydroxyl group of HA. The second product is formed as a result of the addition of the nitrogen atom of HA to the carbon atom of one aldehyde group of Gly, followed by the migration of the hydrogen atom from the amino group of hydroxylamine to the oxygen atom of the carbonyl group of glyoxal. The identification of the products is confirmed by deuterium substitution and by MP2 calculations of the structures and vibrational spectra of the identified species. 相似文献
38.
Stefan Mommer Kamil Sokoowski Magdalena Olesiska Zehuan Huang Oren A. Scherman 《Chemical science》2022,13(30):8791
Extended polymeric structures based on redox-active species are of great interest in emerging technologies related to energy conversion and storage. However, redox-active monomers tend to inhibit radical polymerisation processes and hence, increase polydispersity and reduce the average molecular weight of the resultant polymers. Here, we demonstrate that styrenic viologens, which do not undergo radical polymerisation effectively on their own, can be readily copolymerised in the presence of cucurbit[n]uril (CB[n]) macrocycles. The presented strategy relies on pre-encapsulation of the viologen monomers within the molecular cavities of the CB[n] macrocycle. Upon polymerisation, the molecular weight of the resultant polymer was found to be an order of magnitude higher and the polydispersity reduced 5-fold. The mechanism responsible for this enhancement was unveiled through comprehensive spectroscopic and electrochemical studies. A combination of solubilisation/stabilisation of reduced viologen species as well as protection of the parent viologens against reduction gives rise to the higher molar masses and reduced polydispersities. The presented study highlights the potential of CB[n]-based host–guest chemistry to control both the redox behavior of monomers as well as the kinetics of their radical polymerisation, which will open up new opportunities across myriad fields.Extended polymeric structures based on redox-active species are of great interest in emerging technologies related to energy conversion and storage.Polyviologens are redox-active polymers based on N-substituted bipyridinium derivatives which have emerged as promising materials for energy conversion and storage.1–5 Their physicochemical properties can be adjusted through copolymerisation of the redox-active viologen monomers.6–8 The resultant materials are stable, water soluble and exhibit fast electron transfer kinetics. Polyviologens have been commonly fabricated through step-growth polymerisation in linear and dendritic architectures,9–13 as supramolecular polymers,14–16 networks,6,17,18 and covalent organic frameworks.19,20 Alternatively, anionic/cationic or metathesis-based polymerisations are used to avoid interference of radical-stabilising monomers with the radical initiators, however, these techniques are highly water- and/or oxygen-sensitive.21,22 When free-radical polymerisation (FRP) is conducted in the presence of viologen species, its reduction can cause a depletion of active radicals and thus disruption of the polymerisation process. Despite varying solvents, comonomers and initiator loadings, the direct FRP of viologen-containing monomers remains therefore limited to molar masses of 30 kDa.23–25 Accessing higher molar masses has been possible via post-polymerisation modification,26–28 which has impacted the electrochemical properties of the resultant materials.29,30 Alternative strategies to access higher molar masses of redox-active polymers and control their polymerisation are highly desirable.Incorporation of cucurbit[n]uril (CB[n]) macrocycles have lead to a variety of functional materials through host–guest chemistry.31–34 Moreover, the redox chemistry of viologens can be modulated through complexation with CB[n].35–38 Specifically, CB[n] (n = 7, 8) can tune the redox potential of pristine viologens and efficiently sequester monoreduced viologen radical cations, avoiding precipitation in aqueous environments. Further to this, we recently demonstrated that the viologen radical cation is stabilised by −20 kcal mol−1 when encapsulated in CB[7].39Consequently, we envisioned that incorporating CB[n]s as additives prior to polymerisation could (i) overcome current limits in accessible molar masses, (ii) increase control over FRP of viologen-based monomers through encapsulation and (iii) enable separation of radical species avoiding aggregation.Here, we demonstrate a new approach to control FRP of redox-active monomers leading to high molar masses and decreased dispersity of the resultant polymers. In absence of CB[n], co-polymerisation of the N-styryl-N′-phenyl viologen monomer 12+ and N,N-dimethylacrylamide (DMAAm) only occurs at high initiator loadings (>0.5 mol%, Fig. 1a), leading to low molecular weights and high polydispersity. Using our synthetic approach, 12+ is efficiently copolymerised with DMAAm in the presence of CB[n] (n = 7, 8) macrocycles resulting in control of the polymer molar mass across a broad range, 4–500 kDa (Fig. 1b). Finally, CB[n] are successfully removed from the polymer via competitive host–guest binding and dialysis. Spectroscopic and electrochemical studies revealed that solubilisation/stabilisation of the reduced species and/or shielding of the redox-active monomers from electron transfer processes was responsible for this enhancement.Open in a separate windowFig. 1Schematic representation of the investigated polymerisation. (a) Conventional free radical polymerisation either completely fails to copolymerise redox-active monomers (low initiator loading) or delivers copolymers with limited molar masses and high dispersities (high initiator loading). (b) CB[n]-mediated protection suppresses interference of viologen monomers with radicals formed through the initiation process facilitating copolymerisation. The molar mass of the resulting copolymers is readily tunable via the amount of present CB[n] macrocycles and the CB[n] is post-synthetically removed via competitive binding to yield the final copolymer with desired molar mass. Cl− counter-ions are omitted for clarity.Recent studies on symmetric aryl viologens demonstrated 2 : 2 binding modes with CB[8] and high binding constants (up to Ka ∼ 1011 M−2).40,41 Incorporation of polymerisable vinyl moieties, in combination with the relatively static structure of their CB[n] host–guest complexes, was postulated to allow polymerisation without unfavorable side reactions. The asymmetric N-styryl-N′-phenyl viologen monomer 12+ prepared for this study (Fig. S1a and S2–S13†) displays a linear geometry and was predicted to bind CB[n] (n = 7, 8) in a 2 : 1 and 2 : 2 binding fashion (Fig. S1b†).40,42 Binding modes between CB[n] (n = 7, 8) and 12+ were investigated through titration experiments (1H NMR and ITC) which confirmed the formation of 1·(CB[7])2 and (1)2·(CB[8])2 (see Fig. S25 and S26†). 1H NMR titration of CB[7] with 12+ demonstrates encapsulation of both aryl moieties (including the vinyl group) through upfield chemical shifts of the respective signals (Fig. 2a). Similar upfield shifts were observed for CB[8] (Fig. 2c). Different para-aryl substituents (vinyl vs. hydrogen) resulted in either head-to-tail or head-to-head (1)2·(CB[8])2 dimers (Fig. S1b and S26†), a previously reported phenomenon.43 Nonetheless, the reversible nature of the complex renders the vinyl group temporarily available for copolymerisation. In the presence of CB[8], 12+ yields polymer molar masses of up to 500 kDa as its complexation is more robust. ITC data confirmed binding stoichiometry, with binding constants of Ka = 2.64 × 106 M−1 for 1·(CB[7])2 and Ka = 9.02 × 1010 M−2 for (1)2·(CB[8])2 (Table S2, Fig. S29a and b†).Open in a separate windowFig. 2Supramolecular complexation of 12+ and CB[n]. 1H NMR spectra of 12+ at (a) χCB[7] = 2, (b) χCB[n] = 0 and (c) χCB[8] = 1 in D2O. Cl− counter-ions are omitted for clarity.The free radical copolymerisation of 12+ and DMAAm ([M] = 2 M), in the absence of CB[n], was based on optimised DMAAm homopolymerisations (Fig. S14 and S15†) and full conversion was confirmed by 1H NMR spectroscopy (Table S1 and Fig. S16†). 12+ was maintained at 1 mol% relative to DMAAm and by varying the radical initiator concentration molar masses of up to 30 kDa with broad dispersities (Đ = 11.4) were obtained (Fig. S17†). Lower initiator concentrations (<0.25 mol%) limited polymerisation (Mn = 3.7 kDa) and size exclusion chromatography elution peaks exhibited extensive tailing, suggesting that 12+ engages in radical transfer processes.To verify our hypothesis that CB[n] macrocycles can modulate the redox behavior of 12+, FRP of 12+ and DMAAm was conducted with varying amounts of CB[n] (n = 7, 8) (Fig. 3, S18 and S20†). Full conversion of all monomers including their successful incorporation into the polymer was verified via1H NMR spectroscopy and SEC (Fig. S18 and S21–S23†). Using CB[7], the molar mass of the copolymers was tunable between Mn = 3.7–160 kDa (Fig. 3b and S21a†). Importantly, in the presence of CB[8], a broad range of molar masses Mn = 3.7–500 kDa were accessible for 0 < χCB[8] < 1.2 (Fig. S20 and S21b†). Increasing the CB[n] (n = 7, 8) concentration caused dispersity values to converge to Đ = 2.2 (χCB[8] = 1.2, χ is the ratio of CB[n] to the redox-active monomer, Fig. S20†). The copolymers were purified by addition of adamantylamine (competitive binder) prior to dialysis to deliver CB[n]-free redox-active copolymers (Fig. S23†).Open in a separate windowFig. 3(a) In situ copolymerisation of DMAAm with 12+ and CB[7]. (b) Molar mass and dispersity vs. amount of CB[7] in the system. Fitted curve is drawn to guide the eye. Cl− counter-ions are omitted for clarity.The range of molar masses obtainable through addition of CB[n] (n = 7, 8) correlated with the measured Ka (Fig. 3b and S20†). Binding of 12+ to CB[8] was stronger and therefore lower concentrations of CB[8] were required to shift the binding equilibrium and mitigate disruption of the polymerisation. Dispersity values reached a maximum at χCB[7] = 0.6 or χCB[8] = 0.3, suggesting 1+˙ is only partially encapsulated. Consequently, higher CB[n] concentrations can enable FRP with lower initiator concentrations (0.10 mol%, Fig. S19†), which demonstrates the major role of complexation to modulate electron accepting properties of 12+.The redox-active monomer 12+ can engage with propagating primary radicals (Pm˙) to either be incorporated into the growing polymer chain (Pm–12+˙) or to abstract an electron deactivating it (Pm). This deactivation likely occurs through oxidative termination producing 1+˙ (energetic sink), inactive oligo- and/or polymer chains (Pm) and a proton H+, causing retardation of the overall polymerisation. Oxidative terminations have been previously observed in aqueous polymerisations of methyl methacrylate, styrenes and acrylonitriles that make use of redox initiator systems.44–47 Another example by Das et al. investigated the use of methylene blue as a retarder, with the primary radical being transferred to a methylene blue electron acceptor via oxidative termination, altogether supporting the outlined mechanism of our system (extended discussion see ESI, Section 1.4†).48The process of retardation can, however, be successfully suppressed, when monomer 12+ is encapsulated within CB[n] macrocycles. Herein the formation of 1·(CB[7])2 or (1)2·(CB[8])2 results in shielding of the redox-active component of 12+ from other radicals within the system, hampering other electron transfer reactions. This inhibits termination and results in extended polymerisation processes leading to higher molar mass polymers through mitigation of radical transfer reactions. Moreover, suppressing the formation of 1+˙ through supramolecular encapsulation minimises both π and σ dimerisation of the emerging viologen radical species,39 preventing any further reactions that could impact the molar mass or polydispersity of the resulting polymers.Cyclic voltammetry (CV) and UV-Vis titration experiments were conducted to provide insight into the impact of CB[n] on the redox behavior and control over FRP of 12+. Excess of CB[n] (n = 7, 8) towards 12+ resulted in a complete suppression of electron transfer processes (Fig. S31 and S32†). Initially, 12+ shows a quasi-reversible reduction wave at −0.44 V forming 1+˙ (Fig. 4a). Increasing χCB[7], this reduction peak decreases and shifts towards more negative potentials (−0.51 V, χCB[7] = 1) accompanied by the formation of 12+·(CB[7])1. A second cathodic peak emerges at −0.75 V due to the increased formation of 12+·(CB[7])2. At χCB[7] = 2, this peak shifts to −0.80 V, where it reaches maximum intensity, once 12+·(CB[7])2 is the dominating species in solution. When 2 < χCB[7] < 4, the intensity of the reduction peak decreases and the complexation equilibrium is shifted towards the bound state, complete suppression of the reduction peak occurs at χCB[7] = 4. Similarly, the oxidation wave intensity is reduced by 95% at χCB[7] = 4 causing suppression of potential oxidative radical transfer processes (Fig. 4c).Open in a separate windowFig. 4Mechanism of the CB[n]-mediated (n = 7, 8) strategy for the controlled copolymerisation of redox-active monomer 12+. (a) Cyclic voltammogram with varying amounts of CB[7]. (b) UV-Vis titration of 12+ with varying amounts of CB[7]. (c) Intensity decay of the oxidation peak at −0.27 V and change in absorption maximum of 1+˙ at 590 nm vs. χCB[7]. (d) Electron transfer processes of 12+ to generate 1+˙ and 10. (e) Reduction of 12+ resulting in precipitation of 10. (f) Stabilisation of 1+˙ through encapsulation with CB[7]. (g) Protection of 12+ from redox processes through CB[7]-mediated encapsulation.The concentration of 1+˙ can be monitored using UV-Vis (Fig. 4b and S34†).49 Absorbance at 590 nm (λmax) vs. χCB[7] was plotted and the concentration of 1+˙ increases, reaching a maximum at χCB[7] = 4 (Fig. 4c). When χCB[7] > 4, a decrease in concentration of 1+˙ was observed. We postulate the following mechanism: at χCB[7] = 0, 12+ is reduced to produce high concentrations of 1+˙ that partially disproportionates to form 10, which precipitates (Fig. 4e and S34†). When 0 < χCB[7] < 4, increasing amounts of green 1+˙ are stabilised through encapsulation within CB[7] suppressing disproportionation (Fig. 4c (cuvette pictures), Fig. 4f). For χCB[7] > 4, 12+ is protected from reduction through encapsulation (Fig. 4g).To further demonstrate applicability of this strategy, we chose another viologen-based monomer 22+ for copolymerisation (Fig. 5a). As opposed to 12+, CB binds predominantly to the styryl moiety of 22+ (Fig. S27 and S28†).50 ITC data showed that 22+ binds CB[7] in a 1 : 1 fashion with a binding affinity of Ka = 2.32 × 106 M−1 (Fig. S30 and Table S2†). Monomer 22+ was also analysed via CV and showed three reversible reduction waves at −0.91 V, −0.61 V (viologen) and 0.40 V (styrene). Similar to 12+, excess CB[7] selectively protects the molecule from redox processes, while the vinyl moiety remains accessible (Fig. 5a, S33c and d†). For CB[8], only partial suppression of electron transfer processes was observed (Fig. S33e and f†). We therefore chose CB[7] as an additive to increase control over FRP of 22+ (Fig. 5b). Copolymerisation of 22+ (1 mol%) and DMAAm ([M] = 2 M) at χCB[7] = 0 resulted in Mn = 28 kDa. When χCB[7] = 0.1, 0.2 or 0.3, Mn increased gradually from 124 to 230 and 313 kDa, respectively, demonstrating the potential of this strategy for FRP of redox-active monomers. Higher percentages of CB[7] led to copolymers with presumably higher molar masses causing a drastic decrease in solubility that prevented further analysis. Investigations on a broader spectrum of such copolymers, including those with higher contents of 22+ are currently ongoing.Open in a separate windowFig. 5(a) Cyclic voltammogram of viologen-containing monomer 22+ and its complexation with CB[n] (n = 7, 8) at a concentration of 1 mM using a scan rate of 10 mV s−1 in 0.1 mM NaCl solution. (b) Molar mass and dispersity of 22+-containing copolymers vs. equivalents of CB[7]. Cl− counter-ions are omitted for clarity.In conclusion, we report a supramolecular strategy to induce control over the free radical polymerisation of redox-active building blocks, unlocking high molar masses and reducing polydispersity of the resulting polymers. Through the use of CB[n] macrocycles (n = 7, 8) for the copolymerisation of styrenic viologen 12+, a broad range of molar masses between 3.7–500 kDa becomes accessible. Our mechanistic investigations elucidated that the redox behavior of monomer 12+ is dominated by either CB[n]-mediated stabilisation of monoradical cationic species or protection of the encapsulated pyridinium species from reduction. In the stabilisation regime (χCB[7] < 4), 12+ is reduced to form the radical cation 1+˙, which is subsequently stabilised through CB[7] encapsulation. Upon reaching a critical concentration of CB[7] (χCB[7] > 4), the system enters a protection-dominated regime, where reduction of 12+ is suppressed and the concentration of 1+˙ diminishes. The resulting copolymers can be purified by use of a competitive binder to remove CB[n] macrocycles from the product. This strategy was successfully translated to a structurally different redox-active monomer that suffered similar limitations. We believe that the reported strategy of copolymerisation of redox-active monomers will open new avenues in the synthesis of functional materials for energy conversion and storage as well as for applications in electrochromic devices and (nano)electronics. 相似文献
39.
Elena Sinkiewicz-Darol Iwona Adamczyk Katarzyna ubiech Gabriela Pilarska Magdalena Twaruek 《Molecules (Basel, Switzerland)》2022,27(11)
Breast milk is the optimal food for infants and toddlers, providing basic nutrients. It is also a source of many biologically active substances. Among them are hormones responsible for metabolic balance. One of the hormones taken in with breast milk by a breastfed baby is leptin. This hormone is involved in the regulation of appetite, informing the brain about the body’s energy resources. Having the correct mechanisms related to the action of leptin is a factor reducing the risk of obesity. The natural presence of leptin in the composition of breast milk suggests that it has a specific role in shaping the health of a breastfed child. Obesity as a disease of civilization affects more and more people, including children. The development of this disease is multifaceted and determined by many factors, including genetic and environmental factors such as eating habits and low physical activity. Behind obesity, there are complex mechanisms in which many elements of the human body are involved. Understanding the effects of breastfeeding as a natural source of leptin can help prevent childhood obesity and development of this disease in future life. 相似文献
40.
Anna Nowak Joanna Zielonka-Brzezicka Magdalena Peruyska Adam Klimowicz 《Molecules (Basel, Switzerland)》2022,27(11)
Epilobium angustifolium L. (EA) has been used as a topical agent since ancient times. There has been an increasing interest in applying EA as a raw material used topically in recent years. However, in the literature, there are not many reports on the comprehensive application of this plant to skin care and treatment. EA contains many valuable secondary metabolites, which determine antioxidant, anti-inflammatory, anti-aging, and antiproliferative activity effects. One of the most important active compounds found in EA is oenothein B (OeB), which increases the level of ROS and protects cells from oxidative damage. OeB also influences wound healing and reduces inflammation by strongly inhibiting hyaluronidase enzymes and inhibiting COX-1 and COX-2 cyclooxygenases. Other compounds that play a key role in the context of application to the skin are flavonoids, which inhibit collagenase and hyaluronidase enzymes, showing anti-aging and anti-inflammatory properties. While terpenes in EA play an important role in fighting bacterial skin infections, causing, among other things cell membrane, permeability increase as well as the modification of the lipid profiles and the alteration of the adhesion of the pathogen to the animal cells. The available scientific information on the biological potential of natural compounds can be the basis for the wider use of EA in skin care and treatment. The aim of the article is to review the existing literature on the dermocosmetic use of E. angustifolium. 相似文献