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1.
Mar Drugs ; 21(2)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36827138

RESUMO

The content of bioactive compounds in four brown and one red algae from the Adriatic Sea (Dictyota dichotoma, Gongolaria barbata, Ericaria amentacea, Sargassum hornschuchii and Ellisolandia elongata) is explored. The efficiency of two different extraction methods viz. ultrasound-assisted extraction (UAE) and matrix solid-phase dispersion (MSPD) to obtain the extracts rich in phenolic compounds was compared. The effect of the extraction solvent to modulate the phenolic profile was assessed. In general, the mixture ethanol/water in an isovolumetric proportion showed the best results. The total phenolic content (TPC) and antioxidant activity (AA), as well as the individual polyphenolic profile, were evaluated for five target algae. TPC values ranged between 0.2 mg GAE/g (for E. elongata) and 38 mg GAE/g (for S. hornschuchii). Regarding the quantification of individual polyphenols by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, the presence of a high number of hydroxybenzoic acid derivatives (mainly of 3- and 4-hydroxybenzoic acids) in all species was noted. In G. barbata their concentrations reached up to 500 mg/kg. IC50 values (ABTS assay) ranged between 44 mg/L (for S. hornschuchii) and 11,040 mg/L (for E. elongata). This work contributes to the in-depth characterization of these little-explored algae, showing their potential as a natural source of phenolic compounds.


Assuntos
Phaeophyceae , Rodófitas , Sargassum , Cromatografia Líquida , Bioprospecção , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Fenóis/química , Antioxidantes/química , Extratos Vegetais/química
2.
Molecules ; 28(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36615543

RESUMO

The genus Ulex comprises thirteen accepted species of perennial shrubs in the family Fabaceae. In Galicia (Spain) many of these are considered spontaneous colonizing species, which are easy to establish and maintain. Among them, Ulex gallii Planch. is used in traditional medicine for the same anti-infective, hypotensive and diuretic purposes as Ulex europaeus L., which is the most studied species. Likewise, some studies have described the antitumoral properties of several species. However, there are few scientific studies that justify the use of Ulex gallii Planch. and nothing has been reported about its composition to date. In our study, the entire plant was extracted with methanol and the crude extract was subjected to liquid phase extraction with distinct solvents, yielding three fractions: hexane (H), dichloromethane (D) and methanol (M), which were subsequently fractionated. The dichloromethane (D5, D7 and D8) and methanol (M4) sub-fractions showed antiproliferative activity on A549 (lung cancer) and AGS (stomach cancer) cell lines, and caspase 3/7 activity assessment and DNA quantification were also performed. Targeted analysis via UHPLC-QToF, in combination with untargeted analysis via MS-Dial, MS-Finder and Global Natural Products Social Molecular Networking (GNPS), allowed us to tentatively identify different metabolites in these sub-fractions, mostly flavonoids, that might be involved in their antiproliferative activity.


Assuntos
Fabaceae , Plantas Medicinais , Plantas Medicinais/química , Ulex , Fabaceae/química , Metanol/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Espanha , Cloreto de Metileno , Compostos Fitoquímicos/farmacologia
3.
Anal Bioanal Chem ; 414(20): 6233-6246, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35829771

RESUMO

Temporary tattoos and dyes constitute a great analytical challenge in relation to the regulatory control of their ingredients. Most of these commercial products are not labeled according to their content and their chemical nature is highly diverse. Therefore, it is necessary to analyze these complex samples to evaluate the potential presence of metallic impurities, to ensure the safety of cosmetic products contributing to health protection. This study proposes a multi-analytical methodology, which includes handheld X-ray fluorescence (h-XRF) and X-ray diffraction (XRD), complemented by variable pressure scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (VP-SEM-EDS) to fully characterize 34 commercial samples of jagua and henna tattoos and dyes. The approach allowed the identification of the main constituents providing complementary compositional data and differences between sample types were established. In addition, information on the degree of natural pigments homogeneity was also obtained. The results' discussion considering the current European cosmetics regulation may be useful to support the drafting of safety requirements and specific regulation.


Assuntos
Cosméticos , Tatuagem , Corantes , Microscopia Eletrônica de Varredura , Espectrometria por Raios X
4.
Nat Prod Res ; 35(4): 627-632, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30835544

RESUMO

Solid-Liquid Extraction (SLE) using solvent of different polarities (CHCl3, EtOAc, and n-BuOH) has been applied to leaves and fruits from (Crataegus oxyacantha L.), a deciduous shrub with an expected rich phytochemical profile. The total polyphenols content and the radical scavenging activity of each extract were evaluated. These extracts were analyzed by HPLC-DAD and rutin, quercetin-3-glucoside, caftaric and caffeic acid had been positively identified. The phytochemical study of the ethyl acetate extract of C. oxyacantha, led to the isolation and structural elucidation of quercetin (1); quercetin-3-O-ß-glucoside (2); epicatechin (3); naringenin (4), reported for the first time from this species except caffeic acid and epicatechin. These compounds were identified by 1D and 2D NMR combined analysis as well as by MS and UV.The antimicrobial activity of these extracts has also been tested, showing strong antibacterial activity-solvent dependent-against Gram positive bacteria. Additionally, bactericidal power was demonstrated in fruit extracts.


Assuntos
Crataegus/química , Polifenóis/análise , Polifenóis/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Escherichia coli/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Testes de Sensibilidade Microbiana , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/química , Staphylococcus aureus/efeitos dos fármacos
5.
Antibiotics (Basel) ; 11(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35052923

RESUMO

Antibiotic resistance is a growing global problem that affects people, animals, the environment, and the economy. Many clinically relevant bacteria have become resistant to antibiotics, and this fact is emerging as one of the major threats to public health. The lack of new antibiotics, which is due to their time-consuming and costly development, exacerbates the problem. Therefore, it is necessary to identify new antimicrobial agents to treat bacterial and fungal infections. Plant extracts, which are valuable sources of bioactive compounds, mainly polyphenols, play an important role as a new strategy to combat pathogenic microorganisms. There is an extensive body of supporting evidence for the potent antibacterial and antifungal activities of polyphenols. Furthermore, some polyphenols show a synergistic effect when combined with antibiotics and antifungals, suggesting a promising alternative for therapeutic strategies against antibiotic resistance. However, only a few articles are found when searching the antibacterial or antifungal activities of polyphenols employing clinical isolates. Hence, this review focuses on the antimicrobial activity of polyphenols and extracts rich in polyphenols on clinical isolates, organized according to the World Health Organization priority pathogens classification.

6.
Environ Sci Pollut Res Int ; 28(19): 24270-24278, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31939019

RESUMO

Natural extracts containing high polyphenolic concentration possess antibacterial, anti-parasitic and fungicidal activities. The present research characterises two extracts based on white grape marc, a winemaking by-product, describing their physicochemical features and antimicrobial capacities. The main components of these extracts are phenolic acids, flavan-3-ols and their gallates and flavonols and their glycosides. As a result of this complex composition, the extracts showed pronounced bioactivities with potential uses in agricultural, pharmaceutical and cosmetic industries. Polyphenol compounds were extracted by using hydro-organic solvent mixtures from the by-product of Albariño white wines (Galicia, NW Spain) production. The in vitro antimicrobial activity of these extracts was evaluated on Gram-positive and Gram-negative bacteria and Apicomplexan and Oomycota parasites. Microbial species investigated are causing agents of several human and animal diseases, such as foodborne illnesses (Bacillus cereus, Escherichia coli, Salmonella enterica, and Toxoplasma gondii), skin infections and/or mastitis (Staphylococcus aureus and Streptococcus uberis), malaria (Plasmodium falciparum) and plant infections as "chestnut ink" or "root rot" (Phytophthora cinnamomi). Both extracts showed activity against all the tested species, being nontoxic for the host. So, they could be used for the development of biocides to control a wide range of pathogenic agents and contribute to the enhancement of winemaking industry by-products.


Assuntos
Parasitos , Vitis , Animais , Antibacterianos/farmacologia , Bactérias , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais , Espanha , Streptococcus
7.
Biomed Pharmacother ; 132: 110885, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113420

RESUMO

The therapeutic effect of Vaccinium polyphenols against uropathogens has been widely studied. Most attention has focused on the antimicrobial activity against P-fimbriated Escherichia coli strains. The present study investigated the anti-adhesive and anti-biofilm activity of a saline extract of blueberry (Vaccinium corymbosum) targeting intestinal colonization by a highly adherent Klebsiella pneumoniae strain. This strain, responsible for a large outbreak of infection in Spain, was selected on the basis of its remarkable capacity to colonize the gastrointestinal tract of patients. The blueberry extract was obtained using a medium scale ambient temperature system (MSAT) in a novel approach based on the use of an aqueous solvent and addition of mineral salts. The polyphenolic content was determined by liquid chromatography coupled to tandem mass-spectrometry (LC-MS/MS). The findings confirmed that the blueberry extract is a rich source of phenolic compounds, including the most polar polyphenols (mostly non-flavonoids), intermediate polarity compounds (flavan-3-ols and most procyanidins) and low polarity compounds (flavonols and anthocyanins). The extract significantly inhibited biofilm formation and bacterial adhesion to HT-29 colorectal cells by a highly adherent multidrug-resistant K. pneumoniae. Although some individual anthocyanidins (malvidin, delphinidin and cyanidin) and one hydroxycinnamic acid (caffeic acid) proved capable of reducing bacterial adhesion, the unfractionated extract was more active than any of the individual polyphenolic compounds. In addition, the extract displayed considerable potential as an intestinal decolonization treatment in a murine model. The study findings demonstrate the potential value of the V. corymbosum extract as an alternative treatment for K. pneumoniae infections.


Assuntos
Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Mirtilos Azuis (Planta) , Intestinos/microbiologia , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Animais , Antibacterianos/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Mirtilos Azuis (Planta)/química , Modelos Animais de Doenças , Farmacorresistência Bacteriana Múltipla , Frutas , Células HT29 , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/crescimento & desenvolvimento , Camundongos Endogâmicos BALB C , Extratos Vegetais/isolamento & purificação , Polifenóis/isolamento & purificação
8.
Nat Prod Res ; 34(11): 1586-1590, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30345828

RESUMO

The present study investigates the phenolic composition, antioxidant and antimicrobial activities of an ethyl acetate extract from C. triflorus L'Her. The phytochemical study on the aerial parts of C. triflorus belonging to the Fabaceae family led to the isolation and structural elucidation of 5-Hydroxy-7-O-glucosylflavone (P1), 5-Hydroxy-7-O-galactosylflavone (P2), 5,7-Dihydroxy-flavone (P3), 5,7,3'-Trihydroxy,4'-methoxy-flavone (P4). These compounds were identified by 1D and 2D NMR combined analysis as well as by UV.Ethyl acetate extract of C. triflorus showed a significant and dose-dependent antioxidant activity in vitro, related to the presence of phenolics (180.33 ± 12.22 µg GAE/mg) and flavonoids (16.78 ± 1.54 µg QE/mg). The antimicrobial activity was evaluated in vitro against Staphylococcus aureus CECT 240 and Escherichia coli CECT 4099, by agar-diffusion method. The most active antibacterial activity was expressed by ethyl acetate extract of C. triflorus against Gram-positive bacteria S. aureus. The gathered results suggest that C. triflorus polyphenols and flavonoids are closely associated to its antioxidant and antimicrobial properties.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Cytisus/química , Extratos Vegetais/farmacologia , Acetatos/química , Antibacterianos/química , Antioxidantes/administração & dosagem , Antioxidantes/química , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Flavonoides/análise , Flavonoides/química , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenóis/análise , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Staphylococcus aureus/efeitos dos fármacos
9.
Nat Prod Res ; 32(10): 1220-1223, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28503940

RESUMO

The use of a matrix solid-phase dispersion (MSPD) process to extract polyphenols from hawthorn (Crataegus oxyacantha L.) a deciduous shrub with an expected rich phytochemical profile, has been evaluated. MSPD extracts of fruits and leaves have an outstanding content of polyphenols, although the particular phenolic profile is solvent dependent. The extracts were analysed by HPLC-DAD for the accurate identification of the major bioactive polyphenols, some of which have never been described for this species. MSPD has proven to be a good alternative to the classic methods of obtaining natural extracts, fast and with low consumption of organic solvents, therefore, environmentally friendly. The bioactivities can be considered also very remarkable, revealing extracts with high levels of antioxidant activity.


Assuntos
Fracionamento Químico/métodos , Crataegus/química , Polifenóis/isolamento & purificação , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Frutas/química , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/análise
10.
Talanta ; 140: 134-142, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26048835

RESUMO

An important trend in the extraction of chemical compounds is the application of new environmentally friendly, food grade solvents. Ethyl lactate (ethyl 2-hydroxypropanoate), produced by fermentation of carbohydrates, is miscible with both hydrophilic and hydrophobic compounds being a potentially good solvent for bioactive compounds. Despite its relatively wide use as a general solvent, the utilization of ethyl lactate as an extraction solvent has only recently been considered. Here, we evaluate the possible use of ethyl lactate to extract phenolic compounds from wild plants belonging to Cytisus scoparius, and we compare the characteristics of the extracts obtained by Pressurized Solvent Extraction (the total phenolics content, the antioxidant activity and the concentration of the major polyphenols) with those of other extracts obtained with methanol. In order to explore the industrial production of the ethyl lactate Cytisus extract, we also evaluate medium scale ambient temperature setups. The whole plant and the different parts (flowers, branches, and seed pods) were evaluated separately as potential sources of polyphenols. All extracts were analyzed by LC-MS/MS for accurate identification of the major polyphenols. Similar phenolic profiles were obtained when using ethyl lactate or methanol. The main bioactives found in the Cytisus extract were the non-flavonoid phenolic compounds caffeic and protocatechuic acids and 3,4-dihydroxybenzaldehyde; the flavonoids rutin, kaempferol and quercetin; the flavones chrysin, orientin and apigenin; and the alkaloid lupanine. Regarding the comparison of the extraction systems, although the performance of the PLE was much better than that of the ambient-temperature columns, the energy consumption was also much higher. Ethyl lactate has resulted an efficient extraction solvent for polyphenols from C. scoparius, yielding extracts with high levels of plant phenolics and antioxidant activity. The antimicrobial activity of these extracts was also tested, showing antibacterial activity against Gram +ve bacteria. Qualitatively similar extracts were obtained either by using PLE or medium-scale-ambient-temperature systems, these last rendering larger volumes of extract with lower energy cost. Good results have been obtained with whole plant extracts; nevertheless, extracts enriched in a particular polyphenol can be obtained from different parts of the plant.


Assuntos
Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Cytisus/química , Lactatos/química , Extratos Vegetais/química , Polifenóis/isolamento & purificação , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Humanos , Extração Líquido-Líquido , Polifenóis/química , Polifenóis/farmacologia , Espectrometria de Massas em Tandem , Temperatura
11.
Oecologia ; 163(4): 875-84, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20532916

RESUMO

It has been suggested that condition-dependent signals may be a useful measure of environmental quality. In this study, we tested the hypothesis that oil pollution enhances oxidative stress and impairs expression of a carotenoid-based signal in a wild population of the yellow-legged gull (Larus michahellis). During the courtship period, a group of gulls were fed a supplementary diet containing heavy fuel oil from the Prestige oil spill and were compared with control gulls fed a similar supplementary diet without fuel oil. Blood levels of polycyclic aromatic hydrocarbons, the most toxic components of crude oils, were higher (30%) in the Prestige oil-fed gulls than in the control gulls. Plasma concentrations of vitamin E and carotenoids were also significantly higher in the Prestige oil-fed gulls (31 and 27%, respectively). Although, the plasma levels of lipid peroxidation markers were higher (13%) in gulls fed with Prestige oil than in the control gulls, these differences were not significant, possibly because of the small number of gulls analyzed. The red bill spot was significantly smaller (16%) in the oil-fed gulls than in the control individuals. This study provides the first experimental evidence that a carotenoid-based signal in a free-living seabird is affected by exposure to oil pollution and is hence indicative of environmental quality. Since the yellow-legged gull belongs to a complex of species widely distributed throughout the northern hemisphere, the method described may constitute a useful tool for evaluating sub-lethal effects of oil spills in seabirds.


Assuntos
Antioxidantes/metabolismo , Carotenoides/metabolismo , Charadriiformes/sangue , Poluentes Ambientais/efeitos adversos , Óleos Combustíveis/efeitos adversos , Pigmentação/efeitos dos fármacos , Animais , Oceano Atlântico , Desastres , Poluição Ambiental/efeitos adversos , Feminino , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Vitamina E/sangue
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