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1.
J Food Sci Technol ; 61(6): 1201-1213, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38562598

RESUMEN

Vitamin A, also known as retinol, is a fat-soluble vitamin that plays crucial role in various physiological functions In vivo. However, factors such as light, oxygen, and others may impact the stability of VA. To enhance its stability. This study microencapsulated VA, Gelatin, carboxymethyl cellulose, and salt were mixed in a ratio of 5:1:0.1 as the shell material. Additionally, 12% TG and 3.5% sucrose ester were added with core-shell ratio of 1:8. The experimental results indicated that VA microcapsules exhibited an encapsulation efficiency of 81.12%, after 9 weeks of storage this rate decreased to 75.38%, and the encapsulated VA oil did not exhibit extravasation. The addition of an appropriate amount of salt to the shell material enhanced the mechanical properties of the shell material, compared to the shell material without added salt, the leakage of VA in the salt-added sample decreased by 5.8% for 30 min and 14.5% for 60 min. In vitro release experiments showed that after 3 h of incubation in simulated gastric fluid, the microcapsules had an 18.52% release rate. In simulated intestinal fluid, this increased to 66.58%, indicating strong enteric solubility. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05962-w.

2.
Appl Microbiol Biotechnol ; 107(24): 7581-7599, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37801099

RESUMEN

Resveratrol (RES) is a secondary metabolite synthesized by plants in response to environmental stress and pathogen infection, which is of great significance for the industrial production of RES by fermentation culture. In this study, we aimed to explore the biosynthesis pathway of RES and its key enzymes in the Priestia megaterium PH3, which was isolated and screened from peanut fruit. Through Liquid Chromatography-Mass Spectrometry (LC-MS) analysis, we quantified the RES content and distribution in the culture medium and determined that Priestia megaterium PH3 mainly secreted RES extracellularly. Furthermore, the highest production of RES was observed in YPD, yielding an impressive 127.46 ± 6.11 µg/L. By optimizing the fermentation conditions, we achieved a remarkable RES yield of 946.82 ± 24.74 µg/L within just 2 days, which represents the highest reported yield for a natural isolate produced in such a short time frame. Our investigation revealed that the phenylpropane pathway is responsible for RES synthesis in this bacterium, with cinnamate 4-hydroxylase (C4H) identified as the main rate-limiting enzyme. Overall, our findings highlight the robust RES production capabilities of Priestia megaterium PH3, offering novel insights and potential applications for bacterial fermentation in RES production. KEY POINTS: • RES synthesized by the bacterium was confirmed through the phenylpropane pathway. • The key rate-limiting enzyme for biosynthesis-RES is C4H. • RES reached 946.82 ± 24.74 µg/L after fermentation for 2 days.


Asunto(s)
Bacillus megaterium , Resveratrol/metabolismo , Fermentación , Espectrometría de Masas , Bacillus megaterium/metabolismo , Metabolismo Secundario
3.
J Basic Microbiol ; 63(1): 26-38, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36316240

RESUMEN

This study identified the antifungal metabolites produced by Bacillus altitudinis Q7 against Alternaria alternata and investigated the antifungal activity and antifungal action. Lipopeptide, the important secondary metabolites were identified by Fourier transform infrared (FTIR) and liquid chromatography-mass spectrometry as lichenysin. The antifungal activity of lipopeptide on A. alternata was determined by microdilution technique, and its minimum inhibitory concentration was 1.2 mg/ml. Stability test showed that lipopeptide had excellent temperature and pH resistance. To investigate whether lichenysin acted on the cell membrane and changed its permeability, the ultra-violet absorption of protein and nucleic acid were measured using a colorimetric method. The antifungal metabolites produced by B. altitudinis Q7 was lichenysin, which showed stable antifungal activity in the extreme environments. Lichenysin could inhibit A. alternata by altering the permeability of cell membrane, leading to the outflow of proteins and nucleic acids from the cytoplasm. This research suggests the lipopeptide from B. altitudinis Q7 is a potential biological control agent against A. alternata.


Asunto(s)
Antifúngicos , Bacillus , Antifúngicos/química , Lipopéptidos/farmacología , Lipopéptidos/química , Lipopéptidos/metabolismo , Bacillus/metabolismo , Alternaria
5.
Heliyon ; 10(8): e29653, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38660289

RESUMEN

Vitamin degradation may be affected differently by various food matrices. In this study, the kinetics of vitamin A, B1, and C degradation were directly compared in two types of enteral feeding formulas (EFFs) with different energy densities over a nine-month storage period at 4, 25, and 30 °C. The content of vitamins A, B1, and C was measured in the initial and stored formulas. The results justified the finding that the content of these vitamins was gradually decreased with storage time or temperature increases during the period. At each temperature during storage, the degradation of vitamins A, B1, and C followed first-order kinetics, and the rate constants calculated indicated the degradation of vitamins was temperature-dependent. The EFF-B exhibited a higher activation energy for vitamin degradation than that in the EFF-A, and the activation energy indicated an inverse relationship with the fat content of EFFs. The outcomes might provide a reference for the development and application of EEFs.

6.
Adv Biol (Weinh) ; 8(3): e2300541, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38134388

RESUMEN

Seaweeds are a treasure trove of natural secondary metabolites. Terpenoids extracted from seaweeds are shown to possess a variety of antitumor cellular activities. However, due to the complex and diverse structures of terpenoids, their therapeutic targets and complex mechanisms of action have not been clarified. The present study summarises the research on terpenoids from seaweeds in oncological diseases over the last 20 years. Terpenoids show different degrees of inhibitory effects on different types of tumor cells, suggesting that terpenoids in seaweeds may have potential antitumor disease potential. Terpenoids with potential antitumor activity and their mechanism of action are investigated using network pharmacology. A total of 125 terpenoids and 286 targets are obtained. Proto-oncogene tyrosine-protein kinase Src(SRC), Signal transducer and activator of transcription 3 (STAT3), Mitogen-activated protein kinase (MAPK3, MAPK1), Heat shock protein HSP 90-alpha (HSP90AA1), Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), and RAC-alpha serine/threonine-protein kinase (AKT1) are defined as core targets. According to GO function and Kyoto encyclopedia of genes and genomes(KEGG) enrichment analysis, terpenoids may affect the Phoshatidylinositol 3'-kinase (PI3K)-Akt signaling pathway, Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor resistance, Prostate cancer, MAPK signaling pathway, and Proteoglycans in cancer. In addition, the molecular docking results show that the selected terpenoids are all able to bind strongly to the active protein. Terpenoids may slow down the progression of cancer by controlling apoptosis, proliferation, and protein and enzyme binding.


Asunto(s)
Neoplasias de la Próstata , Algas Marinas , Masculino , Humanos , Farmacología en Red , Simulación del Acoplamiento Molecular , Transducción de Señal
7.
Artículo en Inglés | MEDLINE | ID: mdl-38648105

RESUMEN

Sprouts of black beans (Phaseolus vulgaris L.), soybeans (Glycine max L.) and mung beans (Vigna radiata L.) are widely consumed foods containing abundant nutrients with biological activities. They are commonly treated with sulphites for the preservation and extension of shelf-life. However, our previous investigation found that immersing the bean sprouts in sulphite might convert the active components into sulphur-containing derivatives, which can affect both the quality and safety of the sprouts. This study explores the use of FTIR in conjunction with chemometric techniques to differentiate between non-immersed (NI) and sodium sulphite immersed (SI) black bean, soybean and mung bean sprouts. A total of 168 batches of raw spectra were obtained from NI and SI-bean sprouts using FTIR spectroscopy. Four pre-processing techniques, three modelling assessment techniques and four model evaluation indices were examined for differences in performance. The results show that the multiplicative scatter correction is the most effective pre-processing method. Among the models, the accuracy rate of the three models was as follows: radial basis function neural network (95%) > convolutional neural network (91%) > random forest (82%). The overall findings indicate that FTIR spectroscopy, in conjunction with appropriate chemometric approaches, has a high potential for rapidly determining the difference between NI and SI-bean sprouts.


Asunto(s)
Phaseolus , Sulfitos , Espectroscopía Infrarroja por Transformada de Fourier , Sulfitos/análisis , Sulfitos/química , Phaseolus/química , Quimiometría , Glycine max/química , Vigna/química , Fabaceae/química
8.
J Food Sci ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38922905

RESUMEN

Mung bean sprouts are widely consumed as a seasonal fresh vegetable, renowned for their affordability and richness in antioxidants and bioactive compounds. This study employed ultra-high-performance liquid chromatogram-Q-Exactive HF mass spectrometry (UHPLC-QE-MS) and multivariate statistical analysis to comprehensively evaluate the chemical profile of mung bean sprouts following sulfite immersion. The findings revealed a significant alteration in the overall chemical composition of mung bean sprouts following sodium sulfite immersion. Eleven components, including four sulfur-containing compounds, were identified as characteristic markers distinguishing between non-immersed and sodium sulfite-immersed mung bean sprouts. Esterification and addition reactions were inferred to occur during sodium sulfite immersion, leading to the transformation of flavonoid and saponin sulfates. Commercial samples analysis indicated that sulfur-containing compounds were detectable in 9 of 11 commercial mung bean sprouts. Meanwhile, when sodium sulfite concentration exceeded 3.00 mg/mL and immersion time exceeded 360 min, the contents of total polyphenol and flavonoid were significantly reduced and the antioxidant activity was adversely influenced.

9.
J Cosmet Dermatol ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38712728

RESUMEN

BACKGROUND: Papulopustular rosacea (PPR) is a chronic inflammatory disease with a significant impact on facial aesthetics. An impaired skin barrier is an important factor in the development and exacerbation of PPR. Tranexamic acid (TXA) has immune regulatory and anti-inflammatory effects, inhibits angiogenesis and endothelial hyperplasia, and promotes skin barrier repair. AIMS: We investigated the efficacy and safety of oral TXA for PPR treatment. PATIENTS/METHODS: In total, 70 patients were randomly assigned to receive traditional therapy plus oral TXA or traditional therapy alone for 8 weeks, with a 4-week follow-up period. The subjective improvement in rosacea was assessed using the clinical erythema assessment (CEA), investigator's global assessment (IGA), patient self-assessment (PSA) score, rosacea-specific quality of life (RQoL) score, and global aesthetic improvement score (GAIS). An objective improvement in rosacea was assessed using skin hydration, trans-epidermal water loss (TEWL), clinical photography, and an eight spectrum facial imager. RESULTS: CEA/IGA/PSA, dryness, and RQoL scores were significantly lower and GAIS was higher in the TXA group than in the traditional therapy group. Furthermore, oral TXA significantly improved skin barrier function, increased skin hydration, and decreased TEWL, with no significant side effects. Notably, we observed better outcomes and a greater improvement in skin barrier function with TXA treatment in patients with dry-type rosacea than in patients with oily skin. CONCLUSIONS: The addition of oral TXA to traditional therapy can lead to rapid and effective improvements in PPR, which may be attributed to improvements in skin barrier function.

10.
Immun Inflamm Dis ; 11(7): e938, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37506146

RESUMEN

BACKGROUND: Vaccination is an important method for the prevention of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission. There is currently a lack of real-world clinical data regarding the safety and efficacy of coronavirus disease 2019 (COVID-19) vaccines with respect to plaque psoriasis treatment involving tumor necrosis factor-α (TNF-α) and interleukin-17A (IL-17A) inhibitors. METHODS: We longitudinally analyzed 152 patients with plaque psoriasis, 86 of whom received two doses of inactivated COVID-19 vaccine (either BBIBP-CorV or CoronaVac). Comparisons were made between patients undergoing treatment with biologics (TNF- α inhibitors or IL-17A inhibitors) or acitretin. Routine blood tests were used to assess safety; the psoriasis area and severity index (PASI) and dermatology life quality index (DLQI) were used to assess efficacy. RESULTS: After inactivated COVID-19 vaccination, biologics retained considerable advantages in terms of improving skin lesions (measured by PASI) and quality of life (measured by DLQI), compared with conventional treatment (p < 0.05 and p < 0.01, respectively). Routine blood tests and hepatorenal function analyses suggested that inactivated SARS-CoV-2 vaccines did not alter the safety of biologics treatment (p > 0.05). CONCLUSIONS: Inactivated SARS-CoV-2 vaccines do not have significant impacts on the safety and efficacy of biologics (TNF-α inhibitors or IL-17A inhibitors) in patients with moderate to severe plaque psoriasis.


Asunto(s)
Productos Biológicos , COVID-19 , Psoriasis , Humanos , Vacunas contra la COVID-19/efectos adversos , Factor de Necrosis Tumoral alfa , Interleucina-17 , Inhibidores de Interleucina , Productos Biológicos/uso terapéutico , Calidad de Vida , COVID-19/prevención & control , SARS-CoV-2 , Resultado del Tratamiento , Psoriasis/tratamiento farmacológico
11.
Artículo en Inglés | MEDLINE | ID: mdl-37801273

RESUMEN

Biofilm bacteria have stronger resistance to the adverse external environment compared to planktonic bacteria, and biofilms of non-pathogenic bacteria have strong potential for applications in food. In this experiment, Halomonas sp. H09 and Lactobacillus rhamnosus GG, which have film-forming ability in monoculture and better film-forming ability in mixed culture than the two strains alone, were selected as the target strains for mixed culture. According to SEM observation and bacterial dry weight measurement, the target strain formed a dense biofilm on a 0.1 g/L chitosan-modified cellulose III carrier. Furthermore, the presence of extracellular polymeric substances in biofilms was verified by EDS and FTIR. The results showed that 0.1 g/L chitosan-modified cellulose III was an ideal carrier material for immobilization of Halomonas sp. H09 with Lactobacillus rhamnosus GG biofilm. This research provided a basis for the selection of non-pathogenic mixed-bacteria biofilm carriers.

12.
Z Naturforsch C J Biosci ; 78(1-2): 73-81, 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36351234

RESUMEN

An efficient and rapid preparative method for the separation and purification of flavonoid glycosides from the Ginkgo biloba extract (GBE) was developed by sephadex LH-20 and preparative high-performance liquid chromatography (HPLC). 40 g GBE of 24% flavonoids were loaded onto the sephadex LH-20 column and five fractions (1.15, 2.57, 1.32, 4.45, and 3.31 g) at flavonoid content of 72.3, 54.2, 63.5, 51.2, and 59.2% were produced. Ultimately, 12 flavonoid glycosides that are at least purities of 97.7% were obtained from 100 mg of each fraction by preparative HPLC. The fraction A, B, and D each contained two flavonoids, yielded 35, 30, 23, 20, 25, and 25 mg, respectively. The fraction C and E each contained three flavonoids, produced 20, 13, 15, 18, 15, and 20 mg, respectively. The chemical structures of the purified compounds were identified by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI/MS).


Asunto(s)
Flavonoides , Glicósidos , Flavonoides/química , Glicósidos/química , Cromatografía Líquida de Alta Presión/métodos , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray/métodos
13.
Foods ; 12(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37627999

RESUMEN

Type 2 diabetes mellitus (T2DM) has developed into an important health concern worldwide. The discovery of phlorotannins and their efficacy in the treatment of T2DM has become a hotspot for research in various fields. In this study, the potential phlorotannins and mechanism of six brown algae against T2DM were in-depth investigated using biological activity assays, LC-MS, and network pharmacology. First, the ethyl acetate fraction (EA frac.) showed high polyphenolic content and possessed significantly antioxidant and enzyme inhibitory abilities. Further, a total of fifty-nine peaks were obtained from six EA fracs. via UPLC-QE-MS/MS analysis, and fifteen of them were identified as phlorotannins and their isomers or derivatives. In detail, the chemical structures of six phlorotannins were inferred as dibenzodioxine-1,3,6,8-tetraol, bifuhalol, dioxinodehydroeckol, eckol, fucofurodiphlorethol, and fucotriphlorethol; three phlorotannin isomers were deduced to be fucophlorethol, trifucol, triphlorethol A, or triphlorethol B; and the phlorotannin derivative of m/z 263 was determined to be dibenzodioxine-1,2,3,6,8-pentanol or dibenzodioxine-1,2,4,5,7-pentanol. Moreover, 43 T2DM-related targets acted on by these chemicals were identified, and the function of phlorotannin to prevent and treat T2DM was elucidated in a holistic way based on the established compound-target-disease network, and GO function and KEGG pathway enrichment analysis.

14.
Front Med (Lausanne) ; 10: 1239869, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37724178

RESUMEN

Background: Steroid-induced rosacea is a severe withdrawal reaction which can occur after the frequent and excessive topical use of steroids on the face. The Janus kinase (JAK)-signal transducers and activators of transcription signaling pathway is involved in many biological processes and may play a role in the development of steroid-induced rosacea. Objective: To observe the efficacy and safety of the JAK1 inhibitor abrocitinib in the treatment of steroid-induced rosacea. Methods: Four Chinese female patients were treated with orally-administered abrocitinib, a selective JAK1 inhibitor with a good safety profile, for steroid-induced rosacea. Results: Abrocitinib treatment resulted in improved skin condition and lowered Dermatology Life Quality Index scores in each of the four patients. No discomfort was reported and no adverse effects were observed. Conclusion: The JAK1 inhibitor abrocitinib is a promising potential treatment for steroid-induced rosacea.

15.
Int J Biol Macromol ; 253(Pt 4): 127063, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37748587

RESUMEN

Ginkgo seed protein (GSP) has excellent processing characteristics and antioxidant properties. In this study, Gingko endophytic protein (GEP) was synthesized by Ginkgo endophytic Pseudomonas R6. SDS-PAGE analysis indicated that the molecular weights of GSP and GEP were mainly distributed at 17 KDa and 48 KDa, respectively. FTIR showed that GEP and GSP exhibited characteristic absorption in the amide I, II, and III bands, and absorption in amide A and B indicated the presence of hydrogen bonding. HPLC analysis showed that both proteins had 17 amino acids, but their relative abundance was different, with GSP having the highest Ser content (74.713 mg/g) and GEP having the highest Val content (35.905 mg/g). Stomata were observed on the surface of both proteins by SEM, and there were lamellar and some spherical structures on GEP, while the opposite was observed on GSP. GEP had superior solubility, OHC, FC and EC, while GSP showed good WHC. Both proteins exhibited antioxidant activities, with GSP exhibiting stronger hydroxyl radical scavenging ability than GEP, with IC50 of 0.46 mg/mL and 1.54 mg/mL, respectively. This work demonstrates the antioxidant potential of GEP as an alternative to GSP in the food industry.


Asunto(s)
Antioxidantes , Ginkgo biloba , Antioxidantes/química , Ginkgo biloba/química , Semillas/química , Amidas/análisis
16.
Prostaglandins Other Lipid Mediat ; 99(1-2): 1-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22609276

RESUMEN

Beta-eleostearic acid (ß-ESA, 9E11E13E-18:3), a linolenic acid isomer with a conjugated triene system, is a natural and biologically active compound. Herein, we investigated effects of ß-eleostearic acid on T24 human bladder cancer cells. In this study, results showed that ß-eleostearic acid had strong cytotoxicity to induce cell apoptosis, which was mediated by reactive oxygen species (ROS) in T24 cells. The cell viability assay results showed that incubation with ß-eleostearic acid concentrations of 10-80µmol/L caused a dose- and time-dependent decrease of T24 cell viability, and the IC(50) value was 21.2µmol/L at 24h and 13.1µmol/L at 48h. Annexin V/PI double staining was used to assess apoptosis with flow cytometry. Treatment with ß-eleostearic acid caused massive ROS accumulation and GSH decrease, which lead to activation of caspase-3 and down-regulation of Bcl-2 indicating induction of apoptosis. Subsequently, N-acetyl-l-cysteine (NAC) and PEG-catalase effectively blocked the ROS elevated effect of ß-eleostearic acid, which suggested that ß-eleostearic acid-induced apoptosis involved ROS generated. Additionally, we found that treating T24 cells with ß-eleostearic acid induced activation of PPARγ. A PPARγ-activated protein kinase inhibitor was able to partially abrogate the effects of ß-eleostearic acid. These results suggested that ß-eleostearic acid can induce T24 cells apoptosis via a ROS-mediated pathway which may be involved PPARγ activation.


Asunto(s)
Ácidos Linolénicos/farmacología , Acetilcisteína/farmacología , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Inhibidores de Caspasas/farmacología , Catalasa/farmacología , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Glutatión/metabolismo , Humanos , PPAR gamma/antagonistas & inhibidores , Polietilenglicoles/farmacología , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/metabolismo
17.
Phys Chem Chem Phys ; 14(47): 16258-66, 2012 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-23114618

RESUMEN

Water-soluble fluorescent quantum dots (QDs) have been widely used in biological and biomedical fields, and the interaction between QDs and proteins and the conformational structure of the protein in the bioconjugate has attracted increasing attention. In this study, UV-Vis spectroscopy, fluorescence quenching, CD spectra, gel electrophoresis and Fourier transform infrared (FTIR) spectroscopic techniques were used to systematically investigate the interaction between type II restriction endonuclease (EcoRI) and CdS QDs and the conformational structure of EcoRI in the EcoRI-CdS QDs bioconjugates. The results indicated that electrostatic interactions played a major role in the binding reaction at pH 6.0, and the nature of quenching was static, resulting in forming CdS QDs-EcoRI bioconjugates. FTIR and CD spectra studies indicated a decrease of α-helical and turn structures accompanied by the increase of ß-sheet structures of EcoRI in the bioconjugates. This study showed that the interaction between EcoRI and CdS QDs resulted in a change in the secondary structure of EcoRI after it was conjugated with CdS QDs, but the enzyme activity was maintained.


Asunto(s)
Compuestos de Cadmio/química , Desoxirribonucleasa EcoRI/química , Enzimas Inmovilizadas/química , Escherichia coli/enzimología , Puntos Cuánticos , Sulfuros/química , Escherichia coli/química , Conformación Proteica , Análisis Espectral
18.
Microsc Microanal ; 18(4): 885-91, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22849803

RESUMEN

The self-assembly of α,ω-dihexylsexithiophene molecules on an Au(111) surface was examined by using scanning tunneling microscopy at room temperature, revealing the internal molecular structures of the sexithiophene backbones and the hexyl side chains. The α,ω-dihexylsexithiophene formed a large and well-ordered monolayer in which the molecule lay flatly on the Au(111) surface and was separated into two chiral domains. A detailed observation reveals that the admolecules were packed in one lamellae with their molecular axis aligned along the main axis of the Au(111) substrate with their hexyl chains deviated from <110> direction of the Au(111) substrate by 12 ± 0.5°. In contrast to the behavior in the three-dimensional bulk structure, flat-lying adsorption introduced molecular chirality: right- and left-handed molecules separate into domains of two different orientations, which are mirror symmetric with respect to the <121> direction of the Au(111) substrate. Details of the adlayer structure and the chiral self-assembly were discussed here.

19.
Microsc Microanal ; 18(4): 844-51, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22832244

RESUMEN

Self-assembled nanostructures of α,ω-dihexylsexithiophene (DH6T) formed by spreading DH6T solutions onto freshly cleaved mica surface were studied by atomic force microscopy. The effects of solvent and concentration on the nanostructures of DH6T molecules were studied. Flat, well-ordered, and platelet-like domains were observed on mica surfaces after treatment with various polar solvent solutions of DH6T. These domains form a uniform film with height of 2.4 ± 0.2 nm, which is consistent with a 45° tilt in the molecular conformation of DH6T on mica surfaces. The formation mechanism of these multilayers is discussed in detail.

20.
Comput Biol Med ; 143: 105241, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35114443

RESUMEN

BACKGROUND: Recently, the value of natural products has been extensively considered because these resources can potentially be applied to prevent and treat coronavirus pneumonia 2019 (COVID-19). However, the discovery of nature drugs is problematic because of their complex composition and active mechanisms. METHODS: This comprehensive study was performed on flavonoids, which are compounds with anti-inflammatory and antiviral effects, to show drug discovery and active mechanism from natural products in the treatment of COVID-19 via a systems pharmacological model. First, a chemical library of 255 potential flavonoids was constructed. Second, the pharmacodynamic basis and mechanism of action between flavonoids and COVID-19 were explored by constructing a compound-target and target-disease network, targets protein-protein interaction (PPI), MCODE analysis, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. RESULTS: In total, 105 active flavonoid components were identified, of which 6 were major candidate compounds (quercetin, epigallocatechin-3-gallate (EGCG), luteolin, fisetin, wogonin, and licochalcone A). 152 associated targets were yielded based on network construction, and 7 family proteins (PTGS, GSK3ß, ABC, NOS, EGFR, and IL) were included as central hub targets. Moreover, 528 GO items and 178 KEGG pathways were selected through enrichment of target functions. Lastly, molecular docking demonstrated good stability of the combination of selected flavonoids with 3CL Pro and ACEⅡ. CONCLUSION: Natural flavonoids could enable resistance against COVID-19 by regulating inflammatory, antiviral, and immune responses, and repairing tissue injury. This study has scientific significance for the selective utilization of natural products, medicinal value enhancement of flavonoids, and drug screening for the treatment of COVID-19 induced by SARS-COV-2.

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