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1.
Chemistry ; 30(10): e202302940, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38078547

RESUMO

Aggregation-Induced Emission (AIE) luminogens have garnered significant interest due to their distinctive applications in different applications. Among the diverse molecular architectures, those based on triphenylamine and thiophene hold prominence. However, a comprehensive understanding of the deactivation mechanism both in solution and films remains lacking. In this study, we synthesized and characterized spectroscopically two AIE luminogens: 5-(4-(bis(4-methoxyphenyl)amino)phenyl)thiophene-2-carbaldehyde (TTY) and 5'-(4-(bis(4-methoxyphenyl)amino)phenyl)-[2,2'-bithiophene]-5-carbaldehyde (TTO). Photophysical and theoretical analyses were conducted in both solution and PMMA films to understand the deactivation mechanism of TTY and TTO. In diluted solutions, the emission behavior of TTY and TTO is influenced by the solvent, and the deactivation of the excited state can occur via locally excited (LE) or twisted intramolecular charge transfer (TICT) state. In PMMA films, rotational and translational movements are constrained, necessitating emission solely from the LE state. Nevertheless, in the PMMA film, excimers-like structures form, resulting in the emergence of a longer wavelength band and a reduction in emission intensity. The zenith of emission intensity occurs when molecules are dispersed at higher concentrations within PMMA, effectively diminishing the likelihood of excimer-like formations. Luminescent Solar Concentrators (LSC) were fabricated to validate these findings, and the optical efficiency was studied at varying concentrations of luminogen and PMMA.

2.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33921982

RESUMO

Fourteen coumarin-derived compounds modified at the C3 carbon of coumarin with an α,ß-unsaturated ketone were synthesized. These compounds may be designated as chalcocoumarins (3-cinnamoyl-2H-chromen-2-ones). Both chalcones and coumarins are recognized scaffolds in medicinal chemistry, showing diverse biological and pharmacological properties among which neuroprotective activities and multiple enzyme inhibition, including mitochondrial enzyme systems, stand out. The evaluation of monoamine oxidase B (MAO-B) inhibitors has aroused considerable interest as therapeutic agents for neurodegenerative diseases such as Parkinson's. Of the fourteen chalcocumarins evaluated here against MAO-B, ChC4 showed the strongest activity in vitro, with IC50 = 0.76 ± 0.08 µM. Computational docking, molecular dynamics and MM/GBSA studies, confirm that ChC4 binds very stably to the active rMAO-B site, explaining the experimental inhibition data.


Assuntos
Chalconas/química , Cumarínicos/química , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/química , Animais , Sítios de Ligação , Relação Dose-Resposta a Droga , Humanos , Ligantes , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Ratos , Relação Estrutura-Atividade
3.
Sensors (Basel) ; 20(3)2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32046240

RESUMO

Detection of an environmental contaminant requires the use of expensive measurement equipment, which limits the realization of in situ tests because of their high cost, their limited portability, or the extended time duration of the tests. This paper presents in detail the development of a portable low-cost spectrophotometer which, by using a specialized chemosensor, allows detection of mercuric ions (Hg2+), providing effective and accurate results. Design specifications for all the stages assembling the spectrophotometer and the elements selected to build them are presented along with the process to synthesize the chemosensor and the tests developed to validate its performance in comparison with a high-precision commercial laboratory spectrophotometer.

4.
Molecules ; 25(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630065

RESUMO

In the present work, the anthelmintic activity (AA) of ethanolic extracts obtained from Gliricidia sepium, Leucaena leucocephala, and Pithecellobium dulce was evaluated using the third-stage-larval (L3) exsheathment inhibition test (LEIT) and egg hatch test (EHT) on Haemonchus contortus. Extracts were tested at concentrations of 0.3, 0.6, 1.2, 2.5, 5.0, 10, 20, and 40 mg/mL. The larval exsheathment inhibition (LEI) results showed that G. sepium achieved the highest average inhibition of 91.2%, compared with 44.6% for P. dulce and 41.0% for L. leucocephala at a concentration of 40 mg/mL; the corresponding IC50 values were 22.4, 41.7, and 43.3 mg/mL, respectively. The rates of egg hatching inhibition (EHI) at a concentration of 5 mg/mL were 99.5% for G. sepium, 64.2% for P. dulce, and 54% for L. leucocephala; the corresponding IC50 values were 1.9 mg/mL for G. sepium, 3.9 mg/mL for P. dulce, and 4.3 mg/mL for L. leucocephala. The species extracts studied here were also analyzed by ultra-high performance liquid chromatography and Orbitrap high resolution mass spectrometry (UHPLC-Q/Orbitrap/MS/MS), resulting in the compounds' identification associated with AA. Glycosylated flavonoids and methoxyphenols were observed in all three species: fatty acids in G. sepium and P. dulce; phenylpropanoids, anthraquinone glycosides, amino acids and glycosylated phenolic acids in G. sepium; and flavonoids in L. leucocephala. Comparatively, G. sepium presented a greater diversity of compounds potentially active against the control of gastrointestinal nematodes, which was associated with the results obtained in the applied tests.


Assuntos
Anti-Helmínticos/farmacologia , Fabaceae/química , Fabaceae/classificação , Flavonoides/farmacologia , Haemonchus/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Haemonchus/efeitos dos fármacos , Técnicas In Vitro , Larva/efeitos dos fármacos , Espectrometria de Massas em Tandem
5.
Molecules ; 24(9)2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035428

RESUMO

Mulinum crassifolium Phil. (Apiaceae) is an endemic shrub from Chile commonly used as infusion in traditional medicine to treat diabetes, bronchial and intestinal disorders and stomach ailments, including ulcers. From the EtOAc extract of this plant, the new mulinane-type diterpenoids 3 and 5 were isolated along with three known diterpenoids. The gastroprotective effect of the infusion of the plant was assayed to support the traditional use and a fast HPLC analysis using high resolution techniques was performed to identify the bioactive constituents. The EtOAc extract and the edible infusion showed gastroprotective effect at 100 mg/kg in the HCl/EtOH induced gastric ulcer model in mice, reducing lesions by 33% and 74%, respectively. Finally, a metabolomic profiling based on UHPLC-ESI-MS/HRMS of the edible infusion was performed and thirty-five compounds were tentatively identified including quercetin, caffeic acid, apigenine glucoside, p-coumaric acid, chlorogenic acids, and caffeoylquinic acids, which have been associated previously with gastroprotective and antiulcer properties. This scientific evidence can support the contribution of polyphenols in the gastroprotective activity of the edible infusion of this plant, and can validate at least in part, its ethnopharmacological use.


Assuntos
Apiaceae/química , Cromatografia Líquida de Alta Pressão , Diterpenos/química , Diterpenos/farmacologia , Trato Gastrointestinal/efeitos dos fármacos , Espectrometria de Massas , Extratos Vegetais/química , Animais , Metaboloma , Metabolômica , Camundongos , Estrutura Molecular
6.
J Enzyme Inhib Med Chem ; 33(1): 936-944, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29734888

RESUMO

UHPLC/ESI/MS identification of organic compounds is the first step in the majority of screening techniques for the characterization of biologically active metabolites in natural sources. This paper describes a method for the fast identification and characterisation of secondary metabolites in Leptocarpha rivularis DC. (Palo negro) extracts by HPLC/UV (DAD)-Mass Spectrometry (HPLC/MS). The plant is used for the treatment of several diseases since pre-hispanic Mapuche times. Thirty-seven compounds were detected in the aqueous edible extract for the first time including 4 sesquiterpenes, 10 flavonoids, 9 oxylipins, 2 organic acids, and 11 phenolic acids. In addition, phenolic content antioxidant and cholinesterase inhibitory activities were measured for the first time using the edible infusion. The total polyphenol content of the infusion was 230.76 ± 2.5 mmol GAE/kg dry weight, while the antioxidant activity was 176.51 ± 28.84; 195.28 ± 4.83; and 223.92 ± 2.95 mmol TE/kg dry weight, for the DPPH, ABTS, and FRAP assays, respectively. The cholinesterase inhibitory activity was 7.38 ± 0.03 and 5.74 ± 0.06 mmol GALAE/kg, for the inhibition of acetylcholinesterase AChE and BChE, respectively, showing that this plant is a candidate for the isolation of compounds that can be useful for the treatment of neurodegenerative diseases. Furthermore, this plant could serve also as a raw material for the production of dietary supplements, due to its content of polyphenolic compounds.


Assuntos
Antioxidantes/farmacologia , Asteraceae/química , Produtos Biológicos/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Inibidores da Colinesterase/farmacologia , Picratos/antagonistas & inibidores , Acetilcolinesterase/metabolismo , Antioxidantes/química , Antioxidantes/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Hidroxibenzoatos/química , Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/farmacologia , Estrutura Molecular , Oxilipinas/química , Oxilipinas/isolamento & purificação , Oxilipinas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
7.
Sensors (Basel) ; 18(9)2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30181437

RESUMO

This work reports the development of a composite of the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BP4) and chitosan (CS) described in previous reports through a new method using cyclic voltammetry with 10 cycles at a scan rate of 50.0 mV s-1. This method is different from usual methods such as casting, deposition, and constant potential, and it allows the development of an electroactive surface toward the oxidation of rutin by stripping voltammetry applied to the detection in tropical fruits such as orange, lemon, and agraz (Vaccinium meridionale Swartz), with results similar to those reported in previous studies. In addition, the surface was characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and Raman spectroscopy. The limit of detection was 0.07 µmol L-1 and the relative standard deviation (RSD) of 10 measurements using the same modified electrode was 0.86%. Moreover, the stability of the sensor was studied for six days using the same modified electrode, where the variation of the signal using a known concentration of rutin (RT) was found to be less than 5.0%. The method was validated using a urine chemistry control spiked with known amounts of RT and possible interference was studied using ten substances including organic and biological compounds, metal ions, and dyes. The results obtained in this study demonstrated that this electrodeveloped composite was sensitive, selective, and stable.


Assuntos
Carbono , Quitosana/química , Técnicas Eletroquímicas , Frutas/química , Líquidos Iônicos/química , Rutina/análise , Eletrodos , Clima Tropical
8.
Sensors (Basel) ; 17(11)2017 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-29156561

RESUMO

A fast, sensitive, and selective method for the simultaneous determination of one pair of synthetic colorants commonly found mixed in food products, Amaranth (AM) and Tartrazine (TZ), based on their adsorption and oxidation on a screen-printed electrode (SPE) is presented. The variation of peak current with pH, supporting electrolyte, adsorption time, and adsorption potential were optimized using square wave adsorptive voltammetry. The optimal conditions were found to be: pH 3.2 (PBS), Eads 0.00 V, and tads 30 s. Under these conditions, the AM and TZ signals were observed at 0.56 and 0.74 V, respectively. A linear response were found over the 0.15 to 1.20 µmol L-1 and 0.15 to 0.80 µmol L-1 concentrations, with detection limits (3σ/slope) of 26 and 70 nmol L-1 for AM and TZ, respectively. Reproducibility for 17.7 µmol L-1 AM and TZ solutions were 2.5 and 3.0% (n = 7), respectively, using three different electrodes. The method was validated by determining AM and TZ in spiked tap water and unflavored gelatin spiked with AM and TZ. Because a beverage containing both AM and TZ was not found, the method was applied to the determination of AM in a kola soft drink and TZ in an orange jelly and a soft drink powder.

9.
Molecules ; 22(11)2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29084151

RESUMO

Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria. Lichens belonging to the Parmeliaceae family comprise 2700 species of lichens, including the Parmotrema genus which is composed of 300 species. The metabolites of this genus include depsides, depsidones, phenolics, polysaccharides, lipids, diphenylethers and dibenzofurans, which are responsible for the biological activities reported including antidiabetic, antihelmintic, anticancer, antioxidant, antibacterial, anti-inflammatory, antimitotic, antitumoral, antifungal, and antioxidant enzyme inhibitory. Due to scarce knowledge of metabolomic profiles of Parmotrema species (P. andinum and P. robustum), a full metabolome study based on ultra-high performance liquid chromatography- diode array detector-electrospray ionization-quadrupole-orbitrap-mass-spectrometry (UHPLC-DAD-ESI-Q-orbitrap MS) was performed for a comprehensive characterization of their substances. From the methanolic extracts of these species, a total of 54 metabolites were identified for the first time using this hyphenated technique, including thirty compounds in P. andinum, and thirty-seven in P. robustum. Moreover, two compounds were not identified as known compounds, and could be new structures, according to our data. This report shows that this technique is effective and accurate for rapid chemical identification of lichen substances and the compounds identified could serve as chemotaxonomic markers to differentiate these ruffle lichens.


Assuntos
Metabolômica/métodos , Metanol/química , Parmeliaceae/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
10.
Molecules ; 23(1)2017 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-29280946

RESUMO

Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria, which are considered among the slowest growing organisms, with strong tolerance to adverse environmental conditions. There are about 400 genera and 1600 species of lichens and those belonging to the Usnea genus comprise about 360 of these species. Usnea lichens have been used since ancient times as dyes, cosmetics, preservatives, deodorants and folk medicines. The phytochemistry of the Usnea genus includes more than 60 compounds which belong to the following classes: depsides, depsidones, depsones, lactones, quinones, phenolics, polysaccharides, fatty acids and dibenzofurans. Due to scarce knowledge of metabolomic profiles of Usnea species (U. barbata, U. antarctica, U. rubicunda and U. subfloridana), a study based on UHPLC-ESI-OT-MS-MS was performed for a comprehensive characterization of their secondary metabolites. From the methanolic extracts of these species a total of 73 metabolites were identified for the first time using this hyphenated technique, including 34 compounds in U. barbata, 21 in U. antarctica, 38 in U. rubicunda and 37 in U. subfloridana. Besides, a total of 13 metabolites were not identified and reported so far, and could be new according to our data analysis. This study showed that this hyphenated technique is rapid, effective and accurate for phytochemical identification of lichen metabolites and the data collected could be useful for chemotaxonomic studies.


Assuntos
Líquens/química , Metabolômica/métodos , Extratos Vegetais/análise , Espectrometria de Massas em Tandem/métodos , Usnea/química , Usnea/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Fungos , Metanol/química , Compostos Fitoquímicos/metabolismo , Extratos Vegetais/química
11.
Bioorg Med Chem Lett ; 26(14): 3220-3222, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27262597

RESUMO

Mulinane diterpenoids isolated from Azorella species have displayed gastroprotective effects in animal models. In this study we have transformed the main constituent, mulin-11,13-dien-20 oic acid from this plant using the filamentous fungus Mucor plumbeus and a ß-cyclodextrin inclusion complex and we have obtained two main products with good yields (33% and 15% for compound 4 and 5, respectively) for further preparation of semisynthetic derivatives to evaluate their gastroprotective effects. In addition, one of the compounds isolated from Azorella cuatrecasasii was new (9-epi-13α-hydroxymulinene 1). Six new derivatives 4a-4c and 5a-5c were then prepared by simple chemical transformations. The structures of all compounds were elucidated by spectroscopic means based on 1D and 2D-NMR techniques. Some 8 diterpenes were evaluated for their gastroprotective effects in the ethanol/HCl-induced ulcer model in mice at 20mg/kg. The highest gastroprotective activity was shown by 7α,16-dihydroxymulin-11,13-dien-20-oic acid 5, which was higher than the reference drug lansoprazole, while 16-hydroxymulin-11,13-dien-20-oic acid 4 was as active as lansoprazole.


Assuntos
Antiulcerosos/farmacologia , Apiaceae/química , Diterpenos/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Úlcera Gástrica/tratamento farmacológico , beta-Ciclodextrinas/farmacologia , Álcoois , Animais , Antiulcerosos/química , Antiulcerosos/isolamento & purificação , Modelos Animais de Doenças , Diterpenos/química , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Mucosa Gástrica/patologia , Ácido Clorídrico , Camundongos , Conformação Molecular , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/patologia , Relação Estrutura-Atividade , beta-Ciclodextrinas/química
12.
Bioorg Med Chem Lett ; 26(23): 5732-5735, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27810240

RESUMO

Natural or synthetic coumarins showed gastroprotective and antiulcer activity in animal models. In this study, we have synthetized twenty coumarins using classic methods to evaluate their gastroprotective effects on the ethanol/HCl-induced gastric lesion model in mice at 20mg/kg. Among the coumarins synthetized, compounds 6 and 10 showed the greatest gastroprotective activity being as active as lansoprazole at 20mg/kg and reducing gastric lesions by 75 and 76%, respectively. Then, in a second experiment, compounds 6 and 10 were re-evaluated in order to understand the possible mode of gastroprotective activity. Regarding coumarin 6, the protective effect was reduced by pre-treatment of the mice with N-ethylmaleimide and l-NAME suggesting that sulfhydryl compounds and endogenous nitric oxide are involved in its gastroprotective activity. While for coumarin 10 the effect was reduced by pre-treatment with indomethacin suggesting that prostaglandins are positively involved in its gastroprotective activity.


Assuntos
Antiulcerosos/química , Antiulcerosos/uso terapêutico , Cumarínicos/química , Cumarínicos/uso terapêutico , Prostaglandinas/metabolismo , Úlcera Gástrica/tratamento farmacológico , Canais de Cátion TRPV/metabolismo , Animais , Antiulcerosos/farmacologia , Cumarínicos/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Úlcera Gástrica/metabolismo , Compostos de Sulfidrila/metabolismo
13.
Biochem Biophys Res Commun ; 463(4): 787-92, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26051278

RESUMO

Abundant evidence indicates that iron accumulation, oxidative damage and mitochondrial dysfunction are common features of Huntington's disease, Parkinson's disease, Friedreich's ataxia and a group of disorders known as Neurodegeneration with Brain Iron Accumulation. In this study, we evaluated the effectiveness of two novel 8-OH-quinoline-based iron chelators, Q1 and Q4, to decrease mitochondrial iron accumulation and oxidative damage in cellular and animal models of PD. We found that at sub-micromolar concentrations, Q1 selectively decreased the mitochondrial iron pool and was extremely effective in protecting against rotenone-induced oxidative damage and death. Q4, in turn, preferentially chelated the cytoplasmic iron pool and presented a decreased capacity to protect against rotenone-induced oxidative damage and death. Oral administration of Q1 to mice protected substantia nigra pars compacta neurons against oxidative damage and MPTP-induced death. Taken together, our results support the concept that oral administration of Q1 is a promising therapeutic strategy for the treatment of NBIA.


Assuntos
Morte Celular/efeitos dos fármacos , Hidroxiquinolinas/farmacologia , Quelantes de Ferro/farmacologia , Mitocôndrias/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Humanos , Ferro/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Neurônios/citologia , Rotenona/farmacologia
14.
Mar Drugs ; 13(4): 1726-38, 2015 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-25830679

RESUMO

Ten known meroterpenoids and the new meroterpenoid 7 were isolated from the Chilean seaweed Stypopodium flabelliforme as their acetylated derivatives. Furthermore, the known metabolite taondiol has been isolated for the first time from this species. The molecular structure of the new metabolite was determined by spectroscopic methods based on 1D- and 2D-NMR. Isolation of 7 represents a key step toward a better understanding of the biogenesis of this class of meroterpenoids. Among the meroditerpenoids isolated, stypodiol, isoepitaondiol, epitaondiol and sargaol exhibited gastroprotective activity on the HCl/Ethanol-induced gastric lesions model in mice. Regarding the mode of gastroprotective action, the activity of epitaondiol was reversed significantly when animals were pretreated with indomethacin, N-ethylmaleimide and N-nitro-l-arginine methyl ester (L-NAME) suggesting that prostaglandins, sulfhydryl groups and nitric oxide are involved in their mode of gastroprotective action. In the case of sargaol the gastroprotective activity was attenuated with indomethacin and N-ethylmaleimide, which suggests that prostaglandins and sulfhydryl groups are also involved in the mode of action using this model.


Assuntos
Antiulcerosos/isolamento & purificação , Modelos Animais de Doenças , Diterpenos/isolamento & purificação , Descoberta de Drogas , Phaeophyceae/química , Alga Marinha/química , Úlcera Gástrica/prevenção & controle , Acetilação , Animais , Antiulcerosos/efeitos adversos , Antiulcerosos/química , Antiulcerosos/uso terapêutico , Linhagem Celular , Chile , Diterpenos/efeitos adversos , Diterpenos/química , Diterpenos/uso terapêutico , Mucosa Gástrica/efeitos dos fármacos , Humanos , Camundongos , Estrutura Molecular , Oceano Pacífico , Phaeophyceae/crescimento & desenvolvimento , Polinésia , Substâncias Protetoras/efeitos adversos , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/uso terapêutico , Distribuição Aleatória , Alga Marinha/crescimento & desenvolvimento , Estereoisomerismo , Terpenos/efeitos adversos , Terpenos/química , Terpenos/isolamento & purificação , Terpenos/uso terapêutico
15.
Org Biomol Chem ; 12(33): 6406-13, 2014 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-25008488

RESUMO

Four new mulinane-type diterpenoids besides the known compounds mulin-11,13-dien-20-oic acid, 13α-hydroxyazorellane, 13ß-hydroxyazorellane, mulinolic acid, azorellanol, and mulin-11,13-dien-18-acetoxy-16,20-dioic acid were isolated from the Chilean plant Azorella trifurcata. One of the new metabolites isolated, 7α-acetoxy-9-epi-13ß-hydroxymulinane, possesses a new trans-syn-trans arrangement in a tricyclic ring system not previously encountered in nature. Among the mulinane diterpenoids isolated, mulin-11,13-dien-20-oic acid showed the gastroprotective effect on HCl-EtOH-induced gastric lesions in mice (ED50 = 55 mg kg(-1)). Regarding the mode of gastroprotective action for this active compound, its effect was reduced by pre-treatment of the mice with indomethacin and N-ethylmaleimide, suggesting that prostaglandins and sulfhydryl compounds are positively involved in the gastroprotective activity using this model.


Assuntos
Apiaceae/química , Diterpenos/uso terapêutico , Gastrite/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Animais , Diterpenos/química , Diterpenos/isolamento & purificação , Etanol/administração & dosagem , Etilmaleimida , Gastrite/induzido quimicamente , Ácido Clorídrico/administração & dosagem , Indometacina , Camundongos , NG-Nitroarginina Metil Éster , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Rutênio Vermelho
16.
Sensors (Basel) ; 14(1): 1358-71, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24419164

RESUMO

Two new coumarin-based "turn-off" fluorescent probes, (E)-3-((3,4-dihydroxybenzylidene)amino)-7-hydroxy-2H-chromen-2-one (BS1) and (E)-3-((2,4-dihydroxybenzylidene)amino)-7-hydroxy-2H-chromen-2-one (BS2), were synthesized and their detection of copper(II) and iron(III) ions was studied. Results show that both compounds are highly selective for Cu²âº and Fe³âº ions over other metal ions. However, BS2 is detected directly, while detection of BS1 involves a hydrolysis reaction to regenerate 3-amino-7-hydroxycoumarin (3) and 3,4-dihydroxybenzaldehyde, of which 3 is able to react with copper(II) or iron(III) ions. The interaction between the tested compounds and copper or iron ions is associated with a large fluorescence decrease, showing detection limits of ca. 10⁻5 M. Preliminary studies employing epifluorescence microscopy demonstrate that Cu²âº and Fe³âº ions can be imaged in human neuroblastoma SH-SY5Y cells treated with the tested probes.


Assuntos
Cumarínicos/química , Fluorescência , Imagem Molecular/métodos , Linhagem Celular Tumoral , Rastreamento de Células , Cobre/química , Corantes Fluorescentes , Humanos , Peróxido de Hidrogênio , Íons/química , Ferro/química
17.
Biomed Pharmacother ; 173: 116307, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38401521

RESUMO

Chagas disease (CHD) is the highest economic burden parasitosis worldwide and the most important cardiac infection, without therapeutic alternatives to halt or reverse its progression. In CHD-experimental models, antioxidant and anti-inflammatory compounds have demonstrated therapeutic potential in cardiac dysfunction. Theobroma cacao polyphenols are potent natural antioxidants with cardioprotective and anti-inflammatory action, which are susceptible to degradation, requiring technological approaches to guarantee their protection, stability, and controlled release. Here, 21 cocoa polyphenol-rich microencapsulates were produced by spray-drying and freeze-drying techniques using two wall materials (maltodextrin and gum arabic). Chemical (total and individual phenolic content and antioxidant activity), structural (morphology), and biological parameters (cytotoxicity, trypanocidal, antioxidant, and immunomodulatory activities) were assessed to determine the most efficient microencapsulation conditions on Trypanosoma cruzi-infected myocardioblast and macrophage cells. Significant antiproliferative properties against infected cells (superior to benznidazole) were found in two microencapsulates which also exhibited cardioprotective properties against oxidative stress, inflammation, and cell death.


Assuntos
Cacau , Trypanosoma cruzi , Humanos , Polifenóis/farmacologia , Polifenóis/química , Antioxidantes/farmacologia , Antioxidantes/química , Cacau/química , Anti-Inflamatórios
18.
Antioxidants (Basel) ; 12(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36829773

RESUMO

Protein aggregation, mitochondrial dysfunction, iron dyshomeostasis, increased oxidative damage and inflammation are pathognomonic features of Parkinson's disease (PD) and other neurodegenerative disorders characterized by abnormal iron accumulation. Moreover, the existence of positive feed-back loops between these pathological components, which accelerate, and sometimes make irreversible, the neurodegenerative process, is apparent. At present, the available treatments for PD aim to relieve the symptoms, thus improving quality of life, but no treatments to stop the progression of the disease are available. Recently, the use of multifunctional compounds with the capacity to attack several of the key components of neurodegenerative processes has been proposed as a strategy to slow down the progression of neurodegenerative processes. For the treatment of PD specifically, the necessary properties of new-generation drugs should include mitochondrial destination, the center of iron-reactive oxygen species interaction, iron chelation capacity to decrease iron-mediated oxidative damage, the capacity to quench free radicals to decrease the risk of ferroptotic neuronal death, the capacity to disrupt α-synuclein aggregates and the capacity to decrease inflammatory conditions. Desirable additional characteristics are dopaminergic neurons to lessen unwanted secondary effects during long-term treatment, and the inhibition of the MAO-B and COMPT activities to increase intraneuronal dopamine content. On the basis of the published evidence, in this work, we review the molecular basis underlying the pathological events associated with PD and the clinical trials that have used single-target drugs to stop the progress of the disease. We also review the current information on multifunctional compounds that may be used for the treatment of PD and discuss the chemical characteristics that underlie their functionality. As a projection, some of these compounds or modifications could be used to treat diseases that share common pathology features with PD, such as Friedreich's ataxia, Multiple sclerosis, Huntington disease and Alzheimer's disease.

19.
Nat Prod Res ; 37(1): 159-163, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34319194

RESUMO

For the first time, we report a green extraction of lichen substances assisted by high power ultrasounds from Hypotrachyna cirrhata using ethyl lactate. This sustainable alternative was comparable, both in isolation and detection of lichen substances, to methanol. In the metabolomic analysis, a total of 77 lichen substances were detected comprising depsides, depsidones, dibenzofurans, organic acids, and lipids. Although the UHPLC/ESI/MS profiles were similar, the antioxidant activity was higher for the ethyl lactate extract. Ethyl lactate can replace toxic organic solvents, such as methanol, in order to provide more sustainable green chemistry methods.


Assuntos
Líquens , Líquens/química , Metanol/química , Solventes , Antioxidantes/química , Extratos Vegetais/química
20.
Nat Prod Res ; 37(12): 2076-2082, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36008873

RESUMO

In this study, isolation and purification of lichen substances from Usnea cornuta were performed using conventional solvents, green solvents and green technologies. In addition, several lichen compounds were tentatively identified by UHPLC/ESI/MS/MS and usnic acid, diffractaic and galbinic acids were quantified as well. Limonene, ethyl lactate and methanol, were compared regarding their extraction properties and antioxidant capacities, determined by DPPH, ORAC, and FRAP assays. In the ethyl lactate, methanol and limonene extracts, 28 compounds in all, were detected for the first time by high resolution UHPLC-MS/MS fingerprinting. Untargeted metabolomics tentatively identified 14 compounds from the methanolic extract, 4 from limonene extract, and 20 metabolites from ethyl lactate extract. The green extract of ethyl lactate showed a similar antioxidant capacity to toxic methanol extract, except at ORAC assay where it was higher. Therefore, ethyl lactate can replace methanol, to provide more sustainable green chemistry methods.


Assuntos
Líquens , Usnea , Antioxidantes/química , Líquens/química , Metanol/química , Espectrometria de Massas em Tandem , Limoneno , Extratos Vegetais/química , Solventes/química , Metabolômica , Usnea/química
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