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1.
J Photochem Photobiol B ; 202: 111636, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31739259

RESUMO

Titanium dioxide (TiO2) nanoparticles (NPs) have been doped with varying amounts (0.005, 0.010 and 0.015 M) of silver nanoparticles (Ag NPs) using hydrothermal method. Further, in this work, a green approach was followed for the formation of Ag@TiO2 NPs using Aloe vera gel as a capping and reducing agent. The structural property confirmed the presence of anatase phase TiO2. Increased peak intensity was observed while increasing the Ag concentration. Further, the morphological and optical properties have been studied, which confirmed the effective photocatalytic behavior of the prepared Ag@TiO2 NPs. The photocatalytic performance of Ag@TiO2 has been considered for the degradation of picric acid in the visible light region. The concentration at 0.010 M of the prepared Ag@TiO2 has achieved higher photocatalytic performance within 50 min, which could be attributed to its morphological behavior. Similarly, anticancer activity against lung cancer cell lines (A549) was also determined. The Ag@TiO2 NPs generated a large quantity of reactive oxygen species (ROS), resulting in complete cancer cell growth suppression after their systemic in vitro administration. Ag@TiO2 NPs was adsorbed visible light that leads to an enhanced anticancer sensitivity by killing and inhibiting cancer cell reproduction through cell viability assay test. It was clear that 0.015 M of Ag@TiO2 NPs were highly effective against human lung cancer cell lines and showed increased production of ROS in cancer cell lines due to the medicinal behavior of the Aloe vera gel.


Assuntos
Antineoplásicos/química , Nanopartículas Metálicas/química , Prata/química , Titânio/química , Células A549 , Aloe/química , Aloe/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Catálise , Sobrevivência Celular/efeitos dos fármacos , Química Verde , Humanos , Luz , Nanopartículas Metálicas/toxicidade , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo
2.
Food Chem ; 308: 125600, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648091

RESUMO

A novel blue pigment was first isolated from Streptomyces sp. A1013Y. The purified component was identified as 4,8,13-trihydroxy-6,11-dione-trihydrogranaticins A (TDTA). Its physical properties were found to be: Molecular weight 462 Da; Color value, E0.1%1cm580 nm = 80; Solubility, it dissolved in organic solvents. In addition, the color of TDTA changed with pH but was found to be relatively stable between 20 and 100 °C, from pH 3 to pH 11, and under UV-light or darkness. TDTA's functional properties was as follows: TDTA showed excellent free radical scavenging properties, IC50 41.04 µg/mL and 13.75 µg/mL using 2, 20-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-n-(3, 2-ethyl-benzothiazole-6-sulfonic acid) ammonium salt (ABTS) respectively. TDTA might be a promising source of natural pigment and bioactive compound used as additive in food industry.


Assuntos
Streptomyces/química , Benzotiazóis/química , Compostos de Bifenilo/química , Cor , Picratos/química , Pigmentação , Solubilidade , Solventes
3.
Carbohydr Polym ; 227: 115348, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590881

RESUMO

Ecofriendly chitosan-gelatin (Ch-ge) bio-composite films containing Quercetin-starch (Q) were synthesized using solution casting method. Physicochemical characteristics and mechanical properties of the resulting chitosan-gelatin containing Quercetin-starch films (Ch-ge-Q) were studied using UV, FTIR, XRD and SEM techniques. The films were also investigated for their swelling, water-vapor permeability (WVP), water solubility properties. The FTIR spectra confirmed the chemical interactions between the chitosan-gelatin and Q. Surface morphology of prepared film was analyzed by the SEM imaging while XRD spectra suggest the expanded crystallinity of the film with the addition of Q. The film also showed enhanced barrier property against UV rays. The reduction of water-vapor permeability and increase in tensile strength while a decrease in elongation at break has been observed in the Ch-ge-Q film compared to Ch-ge film. The antibacterial activity of Ch-ge-Q film against both gram positive (B. substilis) and gram negative (E. coli) bacteria suggested the Q loaded Ch-ge films as more feasible antibacterial candidate especially against the strain E. coli. The antioxidant activity of the Ch-ge-Q film was evaluated using the DPPH and ABTS as standards and corresponded to 81.45% of DPPH and 72.2% of ABTS scavenging activities. It was observed that the film containing Quercetin-starch presented superior antioxidant activity results in comparison to Ch-ge film promising its application in food packaging.


Assuntos
Antibacterianos/química , Antioxidantes/química , Quitosana/química , Embalagem de Alimentos , Gelatina/química , Quercetina/química , Bacillus subtilis/crescimento & desenvolvimento , Benzotiazóis/química , Compostos de Bifenilo/química , Escherichia coli/crescimento & desenvolvimento , Oxigênio/química , Permeabilidade , Picratos/química , Ácidos Sulfônicos/química , Raios Ultravioleta , Água/química
4.
Carbohydr Polym ; 227: 115362, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590882

RESUMO

A new polysaccharide (pFSP) was first isolated from the originally discarded fibrous roots part of Chinese traditional herb, Bletilla striata. pFSP was composed of D-glucose, D-galactose and D-mannose in a molar ratio of 1: 2.03: 3.45 with molecular weight of 9.1 × 104 Da. It could effectively scavenge DPPH and superoxide radicals with inhibition rate of 64.47% and 72.27% at 5.0 mg/ml, higher than that of polysaccharide from Bletilla striata tuber. Structural investigations of the periodate oxidation studies and Smith-degradation as well as the FT-IR spectroscopy were performed, and combined with 1D and 2D NMR spectroscopy, the repeating unit of pFSP contained (1→4)-linked-α-D-Glcp, (1→4)-linked-ß-D-Manp and (1→3,6)-linked-ß-D-Manp units, together with the branches of (1→6)-linked-ß-D-Galp and terminated with (1→)-linked-ß-D-Manp residue.


Assuntos
Antioxidantes/química , Orchidaceae , Polissacarídeos/química , Benzotiazóis/química , Compostos de Bifenilo/química , Espectroscopia de Ressonância Magnética , Picratos/química , Raízes de Plantas , Ácidos Sulfônicos/química , Superóxidos/química
5.
Int J Nanomedicine ; 14: 6679-6690, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695363

RESUMO

Background: The synthesis of silver nanoparticles (AgNPs) using food waste materials and their biomedical applications have garnered considerable attention recently. Methods: Here, we investigated the synthesis of AgNPs using an aqueous extract of outer peel of Pisum sativum under different lighting conditions using standard procedures and explored their antidiabetic, cytotoxicity, antioxidant, and antibacterial potential. Results: Characterization of AgNPs was done by Ultra Violet (UV-VIS) spectroscopy that showed absorption maxima at 456 nm for the samples exposed to laboratory lighting and at 464 nm for the samples exposed to direct sunlight, by scanning electron microscopy and energy-dispersive X-ray analysis that showed the surface nature and their elemental composition with a strong peak at 3 keV that corresponded to Ag (61.85 wt%), by Fourier-transform infrared spectroscopy that predicted the functional groups involved, and by X-ray powder diffraction that showed the structural properties. The average diameter of the synthesized AgNPs was calculated to be in the range of 10-25 nm. AgNPs exhibited promising antidiabetic activity as determined by inhibition of α-glucosidase (95.29% inhibition at 10 µg/mL and IC50 value of 2.10 µg/mL) and cytotoxicity (IC50 value 4.0 µg/mL as calculated from the slope equation) against HepG2 cells. Furthermore, they also exhibited moderate antioxidant activity (50.17% reduction of 1,1-diphenyl-2-picrylhydrazyl at 100 µg/mL) and antibacterial activity against four human pathogenic bacteria (as indicated by 8.70-11.10 mm inhibition zones on agar plates). Conclusion: In conclusion, the results confirm that food waste can be used in the synthesis of AgNPs and that the latter have the potential for applications in various fields including diabetic and cancer treatments as well as in biomedicine for the manufacture of antibacterial coatings in medical devices and instruments.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Química Verde/métodos , Hipoglicemiantes/farmacologia , Nanopartículas Metálicas/química , Ervilhas/química , Extratos Vegetais/química , Prata/química , Bactérias/efeitos dos fármacos , Compostos de Bifenilo/química , Morte Celular/efeitos dos fármacos , Depuradores de Radicais Livres/farmacologia , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Picratos/química , Análise de Regressão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Int J Nanomedicine ; 14: 8409-8419, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695374

RESUMO

Introduction: Hair growth-promoting herbal extract mixtures (4HGF) exhibits significant anti-inflammatory activities relevant to promoting hair growth; however, its efficacy in patients with hair loss has been limited majorly due to its low penetration ability into hair follicles. Herein, we prepared hydrogels via dropwise addition of poly(γ-glutamic acid) (PGA) solution containing 4HGF into chitosan (CS) solution, resulting in quick formation of ~400 nm-sized hydrogel particles through electrostatic interaction-derived ionic gelation with over 50% encapsulation efficiency of 4HGF (PGA-4HGF). Methods: The size and morphology of PGA-4HGF were characterized by TEM, SEM, and dynamic light scattering analyses. Encapsulation efficiency and loading capacity of 4HGF within PGA-4HGF, as well as in vitro release profiles were determined by simply measuring the characteristic absorbance of 4HGF. Penetrating efficiency of PGA-4HGF was evaluated by tracking the respective fluorescence through model porcine skin with confocal laser microscope system. By treating PGA-4HGF on telogenic mice and dermal papilla cells (DPCs), we evaluated the size of hair bulbs in mice, as well as morphological changes in DPCs. Results: Negligible and sustained release of entrapped 4HGF from the hydrogel nanoparticles were observed under acidic and physiological pH conditions, respectively, which is quite advantageous to control their release and prolong their hair growth-promoting effect. The hydrogel nanoparticles were penetrable through the porcine skin after incubation with or without shaking. After treating telogenic mice and DPCs with PGA-4HGF, we detected enlargement of hair bulbs and remarkable shape changes, respectively, thereby showing its potential in induction of hair growth. Conclusion: These results suggest that the hydrogel nanoparticle formulation developed in this study can be employed as a potential approach for the preservation of hair growth-promoting compounds, their delivery of into hair follicles, and enhancing hair growth.


Assuntos
Quitosana/química , Fermentação , Folículo Piloso/crescimento & desenvolvimento , Hidrogéis/química , Nanopartículas/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Ácido Poliglutâmico/análogos & derivados , Animais , Compostos de Bifenilo/química , Sistemas de Liberação de Medicamentos/métodos , Feminino , Depuradores de Radicais Livres/farmacologia , Folículo Piloso/efeitos dos fármacos , Humanos , Camundongos Endogâmicos C57BL , Nanopartículas/ultraestrutura , Tamanho da Partícula , Picratos/química , Ácido Poliglutâmico/química , Temperatura Ambiente
7.
Int J Nanomedicine ; 14: 7707-7727, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571873

RESUMO

Background: The encapsulation of plant essential oils (EOs) with polymeric materials (e.g. chitosan (CS) and N, N, N-trimethyl chitosan (TMC)) and the further reduction of the polymers into their nano sizes are gaining research interest in nanotechnology due to potential applications in medical drug delivery systems as well as the food and pharmaceutical industry. The present study reports a novel approach for the synthesis of Ocimum gratissimum essential oil (OGEO)-loaded CS and TMC nanoparticles with distinct bioactive and physiochemical properties. Methods: The OGEO-loaded CS and TMC nanoparticles were characterised using various microscopic and spectroscopic techniques. The bioactive compounds in Ocimum gratissimum methanolic extract (OG-MeOH) and EOs was evinced with gas chromatography-mass spectrometry (GC-MS). Total phenolic content (TPC) of OGEO and OG-MeOH was determined using the Folin-Ciocalteu method. The in vitro drug release kinetic pattern was ascertained by membrane dialysis, while antioxidant activity was determined by the 2,2-diphenyl-1picrylhydrozyl (DPPH) free radical scavenging method. The disc diffusion method was used for antibacterial activity evaluation, while MTT and a trypan blue dye exclusion assay were used to assess cytotoxic activity on MDA-MB-231 breast cancer cells. Results: GC-MS analysis revealed components that have not been previously reported for Ocimum gratissimum. The maximum OGEO cumulative drug release percentage in vitro was observed at pH 3 for both OGEO-loaded chitosan nanoparticles (OGEO-CSNPs) and OGEO-loaded N, N, N-trimethyl chitosan nanoparticles (OGEO-TMCNPs). The antioxidant activity of OGEO-CSNPs and OGEO-TMCNPs never reached a steady state after 75 h. OGEO-TMCNPs exhibited antibacterial activity at a lower concentration for both Gram-negative and Gram-positive food pathogens. In vitro cytotoxicity revealed the increased toxicity of OGEO-TMCNPs on MDA-MB-231 breast cancer cell lines. Conclusion: OGEO-loaded CS and TMC nanoparticles were synthesised using a novel material optimisation approach. The synthesised nanoparticles have shown a promising application in the pharmaceutical and food industries.


Assuntos
Quitosana/química , Liberação Controlada de Fármacos , Nanopartículas/química , Ocimum/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Depuradores de Radicais Livres/química , Humanos , Cinética , Metanol/química , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura , Tamanho da Partícula , Fenóis/análise , Picratos/química , Extratos Vegetais/farmacologia , Óleos Vegetais/química , Eletricidade Estática
8.
Mater Sci Eng C Mater Biol Appl ; 104: 109862, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500010

RESUMO

Metal-organic framework (MOF) based graphene oxide (GO) recently merits of attention because of the relative correspondence of GO with metal ions and organic binding linkers. Furthermore, introducing the GO to the Co-MOF to make a new nanoporous hybrid have are improved the selectivity and stability of the Co-MOF. Here the graphene oxide/cobalt metal organic framework (GO/Co-MOF) was synthesized by a solvothermal process using cobalt salt and terephthalic acid and used for biocidal activity, against the growth of the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. X-ray diffraction, Fourier transform infrared spectroscopy and Raman spectroscopy were confirmed the successful synthesize of metal organic framework and incorporation of Co-MOF in to GO sheets. Scanning electron microscopy was showed the cornflower structure of GO/Co-MOF, and transmission electron microscopy was confirmed, the Co-MOF are decorated on GO. Cytotoxicity study of GO/Co-MOF using 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide (MTT) cell viability assay showed the biocompatibility to human fibroblasts cell over 72 h. The growth inhibition of the Escherichia coli and Staphylococcus aureus bacteria are reached over 99% for bacteria concentration of 100 µg/mL. The excellent antibacterial activity of GO based Co-MOF is linked to synergistic effect of sharp edges of the GO sheets and the toxic effect of cobalt ions (Co2+) which are released from their surfaces. The GO/Co-MOF radical scavenging assay was measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) antioxidant assay for samples incubated with cells which confirmed the minimum radicals' toxicity on bacteria. This novel graphene oxide based MOF with its intrinsic superior porous structure, highly active metal coordination, and commercial linker, is an excellent promising candidate to use in biological and pharmaceutical applications as high potential sustained bactericidal materials.


Assuntos
Antibacterianos/farmacologia , Cobalto/farmacologia , Grafite/farmacologia , Estruturas Metalorgânicas/farmacologia , Nanoporos , Compostos de Bifenilo/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Picratos/química , Análise Espectral Raman , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/ultraestrutura , Difração de Raios X
9.
Mater Sci Eng C Mater Biol Appl ; 104: 109867, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499952

RESUMO

The objective of this study was to prepare European eel oil (EO) microcapsules using European eel protein isolate (EPI) as a wall material and investigate its oxidative stability. The EPI emulsions were obtained at different EO: EPI ratios (1:1, 1:2 and 1:4, w/w) and using two emulsification procedures: Homogenization (H) and homogenization followed by ultrasonication (HU) treatments. The microcapsules prepared by combining the two emulsification processes (HU) and at core and wall ratio of was 1:4 presented the smallest particles size and the greatest encapsulation efficiency (68.50%) and oxidative stability. Scanning electron microscopy (SEM) images proved the spherical shape of all microcapsules without fissure on the surface. The capsules exhibited an interesting antioxidant activity depending on the EO:EPI ratio, especially for the metal chelating potential. Thus, the effect of ultrasonication process and the EPI concentration on the characteristic, the stability and the antioxidant activity of the encapsulated EO has been proved.


Assuntos
Anguilla/fisiologia , Antioxidantes/farmacologia , Cápsulas/química , Dessecação , Emulsões/química , Óleos de Peixe/química , Proteínas de Peixes/isolamento & purificação , Animais , Compostos de Bifenilo/química , Ácidos Graxos/análise , Depuradores de Radicais Livres/química , Umidade , Oxirredução , Picratos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria , Água
10.
Molecules ; 24(16)2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31430953

RESUMO

Schizochytrium limacinum residue was hydrolyzed with various proteases (papain, trypsin, Flavourzyme, Protamex, and Alcalase 2.4L) to obtain antioxidative peptides. The results showed that the S. limacinum hydrolysates (SLHs) prepared with compound proteases (Protamex and Alcalase 2.4L) had the highest antioxidant activity, which was measured using methods such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability (IC50 = 1.28 mg/mL), hydroxyl radical scavenging ability (IC50 = 1.66 mg/mL), and reducing power (1.42 at 5.0 mg/mL). The hydrolysates were isolated and purified by ultrafiltration, gel filtration chromatography, and reverse-phase high-performance liquid chromatography (RP-HPLC). Through analysis of electrospray ionization-mass spectrometer (ESI-MS/MS), the purified antioxidant peptide was identified as Pro-Tyr-Lys (406 Da). Finally, the identified peptide was synthesized for evaluating its antioxidant activity. The •OH scavenging ability and reducing power of Pro-Tyr-Lys were comparable to those of reduced L-glutathione (GSH). These results demonstrated that the antioxidant peptides from SLHs could potentially be used as effective antioxidants.


Assuntos
Antioxidantes/química , Microalgas/química , Peptídeos/química , Hidrolisados de Proteína/química , Compostos de Bifenilo/química , Depuradores de Radicais Livres/química , Glutationa/química , Hidrólise , Radical Hidroxila/química , Peroxidação de Lipídeos , Peptídeo Hidrolases/química , Picratos/química , Espectrometria de Massas por Ionização por Electrospray , Superóxidos/química
11.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438505

RESUMO

Sagittaria trifolia is a medicinal foodstuff of China and East Asia belonging to the family Alismataceae. Samples of S. trifolia tubers were collected from Meihekow, Siping, Jilin, Harbin and Wuchang from Northeast China. The current study was aimed to evaluate the qualitative and quantitative analysis, antioxidant activity, biochemical analysis and chemical composition of different populations of S. trifolia. By using Folin-Ciocalteu, aluminium chloride colourimetric and 1,1-diphenyl-1-picrylhydrazyl (DPPH), total phenol and flavonoids content and antioxidant activity was analysed. Furthermore, chemical composition, biochemical analysis and mineral substances were also determined. The results showed the presence of flavonoids, phenols, saponins, tannins, glycosides and steroids except for alkaloids and terpenoids by qualitative analysis. Quantitative analysis revealed that highest total phenol, flavonoids content and antioxidant potential identified from Meihekow, i.e., 2.307 mg GAE/g, 12.263 mg QE/g and 77.373%, respectively. Gas chromatography-mass spectrometry results showed the presence of 40 chemical compounds corresponding to 99.44% of total extract that might be responsible for antioxidant properties. Mineral and biochemical analysis revealed the presence of calcium, magnesium, potassium, sodium, iron, copper, zinc and, carbohydrate, protein, fibre and fat contents, respectively. Interestingly, all S. trifolia populations collected from different locations possess similar composition. The dietary values, phytoconstituents, antioxidant activities and nutritional and curative chemical compounds of S. trifolia are beneficial for the nutritherapy of human beings.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Metanol/química , Compostos Fitoquímicos/análise , Sagittaria/química , Compostos de Bifenilo/química , China , Flavonoides/química , Fenóis/química , Picratos/química
12.
Molecules ; 24(16)2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31412565

RESUMO

Twenty commercially available oenological tannins (including hydrolysable and condensed) were assessed for their antiradical/reducing activity, comparing two analytical approaches: The 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging spectrophotometric assay and the cyclic voltammetry (CV) electrochemical method. Electrochemical measurements were performed over a -200 mV-500 mV scan range, and integrated anodic currents to 500 mV were used to build a calibration graph with (+)-catechin as a reference standard (linear range: From 0.0078 to 1 mM, R2 = 0.9887). The CV results were compared with the DPPH• assay (expressed as % of radical scavenged in time), showing high correlation due to the similarity of the chemical mechanisms underlying both methods involving polyphenolic compounds as reductants. Improved correlation was observed by increasing the incubation time with DPPH• to 24 h (R2 = 0.925), demonstrating that the spectrophotometric method requires a long-term incubation to complete the scavenging reaction when high-molecular weight tannins are involved; this constraint has been overcome by using instant CV measurements. We concluded that the CV represents a valid alternative to the DPPH• colorimetric assay, taking advantage of fast analysis and control on the experimental conditions and, because of these properties, it can assist the quality control along the supply chain.


Assuntos
Antioxidantes/química , Compostos de Bifenilo/química , Picratos/química , Taninos/química , Antioxidantes/farmacologia , Compostos de Bifenilo/farmacologia , Picratos/farmacologia , Espectrofotometria
13.
Arch Pharm (Weinheim) ; 352(9): e1900051, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31339585

RESUMO

Chrysin-based sulfonylpiperazines 7a-k were synthesized and investigated for their in vitro free radical scavenging potential as well as cytotoxic efficacies against selected cancer cell lines. Cytotoxicity of the new compounds toward noncancer cells was confirmed using the SRB assay against Madin-Darby Canine Kidney cells. Reaction of piperazine with different substituted benzenesulfonyl chlorides in triethylamine furnished sulfonylpiperazines (3a-k), which were then allowed to react with 7-(4-bromobutoxy)-5-hydroxy-2-phenyl-4H-chromen-4-one (6) prepared reacting chrysin with 1,4-dibromobutane to give the final derivatives 7a-k. The results concluded that chrysin-sulfonylpiperazines exerted better antioxidant and anticancer efficacies than previously studied chrysin-piperazine precursors. For example, compounds 7h, 7j, and 7k with 4-OCF3 , 4-OCH3 , and 2,4-diOCH3 groups exhibited the best antioxidant potential against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals. Moreover, halogenated analogues (7b, 7c, 7g, and 7h) demonstrated promising anticancer potential against SK-OV3, HeLa, and HT-29 cell lines, whereas those bearing a methoxy functional group (7j and 7k) had beneficial effects against the cell lines A-549 and HT-29. Thus, it can be confirmed from the bioassay results that the overall structural design as well as proper substitution is crucial to deliver the anticipated biological effects. Spectroscopic techniques such as FT-IR, 1 H NMR, 13 C NMR, mass and elemental analysis (CHN) were carried out to confirm the final structures.


Assuntos
Antineoplásicos/síntese química , Antioxidantes/síntese química , Flavonoides/química , Células A549 , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Benzotiazóis/química , Compostos de Bifenilo/química , Sobrevivência Celular/efeitos dos fármacos , Cães , Radicais Livres/química , Células HT29 , Células HeLa , Humanos , Concentração Inibidora 50 , Células Madin Darby de Rim Canino , Estrutura Molecular , Picratos/química , Ácidos Sulfônicos/química
14.
Mater Sci Eng C Mater Biol Appl ; 103: 109792, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349416

RESUMO

Curcumin has recently attracted much attention due to the wide range of its physiological actions such as anti-tumor, anti-inflammatory, anti-thrombotic, anti-diabetic and anti-microbial effects. This phytochemical can be used as a sensing material for the detection of chemicals due to its optical properties as a fluorescent polyphenol. Curcumin and its derivatives can make complexes with many cations such as Cu2+, Fe2+, Hg2+, Pt2+, Re3+ and Al3+via bearing 1,3-diketones with keto-enol isomerization. The complexation of curcumin with certain metal ions leads to its solubility in water and producing various hues of colors as well as cytotoxic and antimicrobial effects. Curcumin can also form complexes with certain metal ions and thus serve as a chelating agent for anions such as ClO-, CN-, F- and S2-. Moreover, conjugation of curcumin with some organic compounds such as cysteine and poly-glycerol acrylate provides an efficient fluorescence detection system for picric acid and 2-vinyl pyridine in aqueous media. In this review, we focused on curcumin as a key element in a membrane composition of chemical sensors. In addition, the latest sensing platforms based on curcumin and its derivatives are briefly described.


Assuntos
Curcumina/análogos & derivados , Antioxidantes/química , Técnicas Biossensoriais , Quelantes/química , Complexos de Coordenação/química , Curcumina/farmacologia , Isomerismo , Metais/química , Picratos/análise , Picratos/química
15.
Pak J Pharm Sci ; 32(3): 933-936, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31278702

RESUMO

The main objective of this study was to evaluate the hydroethanolic extract of Senna alata for the possible free radical scavenging and cytotoxic properties. Using such hydroethanolic extract, various in vitro antioxidant assays at different concentrations were performed and analyzed. In all the assays, plant extract has good inhibitory effect. Ethanolic extract of Senna alata was further subjected into cytotoxicity against HepG2 cell line. Accordingly, it was also found that the plant extract has appreciable potency against cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Depuradores de Radicais Livres/farmacologia , Extrato de Senna/farmacologia , Senna (Planta)/química , Antineoplásicos Fitogênicos/química , Compostos de Bifenilo/química , Etanol/química , Depuradores de Radicais Livres/química , Células Hep G2 , Humanos , Radical Hidroxila/metabolismo , Óxido Nítrico/metabolismo , Picratos/química , Folhas de Planta/química , Extrato de Senna/química , Superóxidos/metabolismo
16.
Chemosphere ; 235: 749-756, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31280043

RESUMO

In this study, the copper nanoparticles (Cu NPs) reactivity for degradation of the reactive dye black 5 (RP5), picric acid (PA) and 2,4-D herbicide was evaluated. The RP5 degradation occurred by oxidative via, through hydroxyl radicals generated in situ, with active participation of Cu(I) and H2O2. The use of catalase confirmed the hydrogen peroxide formation in situ. Reduction degradation via electron transfer was also possible. On the other hand, PA had low degradation efficiency (less than 20%) under any conditions studied (similar to those used for RP5). High degradation efficiency for 2,4-D was achieved by the association of the Cu NPs/H2O2. Thus, the behavioral model of Cu NPs has been proven. This behavioral difference of the chemical species to be degraded in relation to the behavior of the Cu NPs was studied, evaluating its redox behavior by voltammetric analyzes. This study aided in the understanding and selection of the chemical species that can be degraded by these NPs.


Assuntos
Ácido 2,4-Diclorofenoxiacético/química , Cobre/química , Nanopartículas/química , Naftalenossulfonatos/química , Picratos/química , Catalase/metabolismo , Herbicidas/química , Peróxido de Hidrogênio/química , Radical Hidroxila , Oxirredução
17.
Int J Biol Macromol ; 137: 139-150, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260772

RESUMO

In the present study, six different polysaccharides (RFPs, MAPs, UWPs, AEPs, HWPs and CEPs) were extracted from Chlorella vulgaris using repeated freeze-thawing, microwave-assisted-, ultrasonic wave-, alkali-, hot water-, and cellulase-based methods; and antioxidant property assays were performed both in vitro and in vivo. Radical-scavenging capacity (using DPPH, superoxide and hydroxyl radicals) and metal chelating ability were assessed in vitro; Caenorhabditis elegans was used to assess antioxidant effects in vivo. Based on the in vitro screening tests, UWPs exhibited high antioxidant capacity. The UWP yield was 17.1% ±â€¯2.2%; the DPPH-, superoxide-, and hydroxyl radical-scavenging rates were 65.1% ±â€¯2.4%, 61.2% ±â€¯2.7%, and 56.2% ±â€¯2.2%, respectively, and the metal chelating ability was 63.6% ±â€¯2.5% at a concentration of 0.4 mg/mL. UWPs also exhibited high antioxidant activity in vivo. UWPs significantly increased the lifespan of C. elegans under oxidative stress induced by hydrogen peroxide compared with the control group, enhanced stress-resistance-related enzymes, including catalase and superoxide dismutase by 7.29% ±â€¯1.8% and 24.41% ±â€¯4.8%, respectively. The results of the present study indicate that the extraction methods of C. vulgaris polysaccharides were a key factor influencing antioxidant activity.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Quelantes/química , Quelantes/farmacologia , Chlorella vulgaris/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Quelantes/isolamento & purificação , Radical Hidroxila/química , Peso Molecular , Monossacarídeos/análise , Estresse Oxidativo/efeitos dos fármacos , Picratos/química , Polissacarídeos/isolamento & purificação , Superóxidos/química , Ondas Ultrassônicas , Água/química
18.
J Enzyme Inhib Med Chem ; 34(1): 1368-1372, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31347930

RESUMO

To develop multifunctional aldose reductase (AKR1B1) inhibitors for anti-diabetic complications, a novel series of 2-phenoxypyrido[3,2-b]pyrazin-3(4H)-one derivatives were designed and synthesised. Most of the derivatives were found to be potent and selective against AKR1B1, and 2-(7-chloro-2-(3,5-dihydroxyphenoxy)-3-oxopyrido[3,2-b]pyrazin-4(3H)-yl) acetic acid (4k) was the most active with an IC50 value of 0.023 µM. Moreover, it was encouraging to find that some derivatives showed strong antioxidant activity, and among them, the phenolic 3,5-dihydroxyl compound 4l with 7-bromo in the core structure was proved to be the most potent, even comparable to that of the well-known antioxidant Trolox. Thus the results suggested success in the construction of potent and selective AKR1B1 inhibitors with antioxidant activity.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Antioxidantes/farmacologia , Desenho de Drogas , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Pirazinas/farmacologia , Antioxidantes/química , Compostos de Bifenilo/química , Inibidores Enzimáticos/química , Hipoglicemiantes/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Picratos/química , Pirazinas/química , Relação Estrutura-Atividade
19.
Molecules ; 24(11)2019 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-31181831

RESUMO

Cadaba rotundifolia (Forssk.) (family: Capparaceae; common name: Qadab) is one of four species that grow in the Red Sea costal region in the Kingdom of Saudi Arabia. The roots and leaves of C. rotundifolia is traditionally used to treat tumors and abscesses in Sudan. A previous phytochemical study of the roots yielded a quaternary alkaloid, but no report on chemical constituents of the aerial parts of the C. rotundifolia growing in Saudi Arabia has been issued so far. Oxidative stress and advanced glycation end products (AGEs) are thought as causal factors in many degenerative diseases, such as Alzheimer's disease, diabetes, atherosclerosis and aging. In this study, a total of twenty compounds, including four previously undescribed acylated kaempferol glucosides, were isolated from the aerial parts of C. rotundifolia collected in Saudi Arabia. These new compounds were identified as kaempferol 3-O-[2-O-(trans-feruloyl)-3-O-ß-d-glucopyranosyl]-ß-d-glucopyranoside (1), kaempferol 3-O-ß-neohesperidoside-7-O-[2-O-(cis-p-coumaroyl)-3-O-ß-d-glucopyranosyl]-ß-d-glucopyranoside (2), kaempferol 3-O-[2,6-di-O-α-l-rhamnopyranosyl]-ß-d-glucopyranoside-7-O-[6-O-(trans-feruloyl)]-ß-d-glucopyranoside (3) and kaempferol 3-O-[2,6-di-O-α-l-rhamnopyranosyl]-ß-d-glucopyranoside-7-O-[6-O-(trans-p-coumaroyl)]-ß-d-glucopyranoside (4). Their structures were established based on UV-visible, 1D, 2D NMR, and HR-ESI-MS analyses. Of the assayed compounds, 17 and 18 showed potent radical scavenging activity with IC50 values of 14.5 and 11.7 µM, respectively, and inhibitory activity toward AGEs together with compound 7 with IC50 values 96.5, 34.9 and 85.5 µM, respectively.


Assuntos
Capparaceae/química , Flavonoides/isolamento & purificação , Compostos de Bifenilo/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Flavonoides/farmacologia , Depuradores de Radicais Livres/química , Produtos Finais de Glicação Avançada/química , Ácido Clorídrico/química , Hidrólise , Hidróxidos/química , Picratos/química , Compostos de Potássio/química , Espectroscopia de Prótons por Ressonância Magnética
20.
J Agric Food Chem ; 67(26): 7526-7529, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31184887

RESUMO

A limitation of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability (DRSA) due to the presence of pigments and colors in the extracts of plant-based foods was addressed. The pigments present in the test samples absorb in the same wavelength region as the DPPH radicals; this interferes with the elaborate absorbance readings of the DPPH radicals. In this contribution, electron paramagnetic resonance (EPR) spectroscopy for DPPH assay is proposed in order to avoid this limitation. In the EPR-DPPH assay, the underestimation of the radical scavenging abilities of four different pigment-containing extracts was corrected and this reflected up to a 16.1% change compared to the original values. Thus, the EPR-DPPH assay eliminated interference from the pigments coexisting in the reaction medium and improved the accuracy of the DPPH radical scavenging potential of such extracts. The principle of the proposed solution might also be employed in other assays which suffer from pigment interference.


Assuntos
Compostos de Bifenilo/química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Depuradores de Radicais Livres/química , Picratos/química , Pigmentos Biológicos/química , Extratos Vegetais/química , Beta vulgaris/química , Capsicum/química , Cor , Rubus/química
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