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1.
Chem Biodivers ; 20(3): e202200890, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36786298

RESUMO

The present study shows the chemical profile and cytotoxic properties of the ethanolic extracts of Inula viscosa from Northeast Algeria. The extract was obtained by maceration using ethanol. Its phenolic profile was determined using ultra-high-performance liquid chromatography coupled with a diode array detector and an electrospray mass spectrometer (UHPLC-DAD-ESI/MS), which allowed the identification and quantification of 17 compounds, 1,5-O-caffeoylquinic acid being the most abundant. The cytotoxic activity was assessed against human gastric cancer (AGS) and human non-small-cell lung cancer (A549) cell lines, whereas ethanolic extract elicited nearly 60 % and 40 % viability loss toward AGS and A549 cancer cells, respectively. Results also showed that cell death is caspase-independent and confirmed the involvement of RIPK1 and the necroptosis pathway in the toxicity induced by the I. viscosa extract. In addition, the ethanolic extract would not provoke morphological traits in the cancer cells. These findings suggest that I. viscosa can be a source of new antiproliferative drugs or used in preparation plant-derived pharmaceuticals.


Assuntos
Asteraceae , Carcinoma Pulmonar de Células não Pequenas , Inula , Neoplasias Pulmonares , Humanos , Células A549 , Asteraceae/química , Etanol , Inula/química , Neoplasias Pulmonares/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química
2.
Chem Biodivers ; 19(12): e202200367, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36274055

RESUMO

The chemical profile of the hexane extracts of the subspecies carbonellii, greuteri, marginata, trialata, and vejerensis of Calendula suffruticosa growing in Spain, herein described for the first time, were studied to access their value as a chemo taxonomical tool and search for potentially useful compounds. The subsp. greuteri and carbonellii showed higher extract yields. Terpenoids were the most abundant chemical class in subsp. carbonellii, greuteri, trialata, and vejerensis, while alkanes were the most abundant in subsp. marginata. Differences in chemical constituents were identified among the subspecies of C. suffruticosa analysed, which the PCA can prove. The subsp. trialata and greuteri showed more significant phytochemical similarity, which might indicate genetic proximity between these two subspecies. C. suffruticosa subsp. marginata presented the fewest number of compounds and in the smallest quantities, and C. suffruticosa subsp. vejerensis presented the largest number, however, both showed no alcohols. Furthermore, some of the compounds found in significant amounts are known for their pharmacological and nutraceutical properties, denoting potential use.


Assuntos
Calendula , Hexanos , Calendula/química , Espanha , Alcanos/análise , Extratos Vegetais/química
3.
Molecules ; 27(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36557791

RESUMO

In the present study, two extracts from the aerial parts of the endemic species Satureja hispidula were analyzed for the first time by ultra-high-performance liquid chromatography coupled with a diode array detector and an electrospray mass spectrometer (UHPLC-DAD-ESI/MS) method in order to identify and quantify their phenolic compounds. These extracts' antioxidant, α-glucosidase and α-amylase inhibitory activities were also evaluated. UHPLC-DAD-ESI/MS allowed the identification of 28 and 20 compounds in the ethanolic and aqueous extracts, respectively; among them, 5-O-caffeoylquinic acid was the most abundant in both extracts. The biological assay results indicate that the species S. hispidula, besides its high antioxidant power, is also potentially useful for inhibiting the α-glucosidase enzyme. In both antioxidant and α-glucosidase inhibitory assays, the aqueous extract exhibited the most promising results, significantly better than the standards used as positive controls.


Assuntos
Hiperglicemia , Satureja , Antioxidantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , alfa-Glucosidases/metabolismo , Argélia , Cromatografia Líquida de Alta Pressão
4.
Chem Biodivers ; 18(6): e2100120, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34008318

RESUMO

Calendula suffruticosa subsp. algarbiensis (Boiss.) Nyman is very common on the Portuguese coast, but it has only recently begun to be studied chemically and belongs to a genus of difficult taxonomic classification. To improve the knowledge on the chemical variability of this taxon and evaluate the possible use of this tool for taxonomical purposes, the aim of this work was to determine the extent of chemical variation between individuals collected in the same geographic region, and to compare with samples mixing fragments of several individuals each (populations) from different local environments. Overall, hexane extract analysis by GC/MS allowed to identify 42 compounds, eight fatty acids, 24 terpenoids, three alcohols, five alkanes, and two pollutants. Greater chemical differences were found between individuals, grown in the same region, than were found between population samples from different regions. Additionally, 25 phytochemicals were identified for this taxon for the first time and may be used for taxonomic classification, even to distinguish between subspecies of C. suffruticosa. Furthermore, plants collected near urban areas accumulated pollutants, indicating the importance of controlling local environmental conditions when C. suffruticosa cultivation is for human consumption.


Assuntos
Calendula/química , Hexanos/química , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Humanos , Compostos Fitoquímicos/química , Extratos Vegetais/química
5.
Molecules ; 24(5)2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30857362

RESUMO

The hemi-synthesis of chiral imine, benzimidazole and benzodiazepine structures is reported by the condensation of (S)-(-)-perillaldehyde, the major phytochemical of Ammodaucus leucotrichus subsp. leucotrichus essential oil, with different amine derivatives of 2,3-diaminomaleonitrile, o-phenylenediamine and 3-[(2-aminoaryl)amino]dimedone. The reaction proceeds in situ at ambient temperature without prior isolation of the natural (S)-(-)-perillaldehyde. Final products precipitate in the ethanolic reaction medium. 2D NMR and single-crystal X-ray diffraction studies were used to unequivocally characterize the structures in solution and in the solid state, respectively. Chiral HPLC analysis confirms the formation of unique enantiomers and diastereomeric mixtures.


Assuntos
Apiaceae/química , Benzodiazepinas/química , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Óleos Voláteis/química , Difração de Raios X
6.
Molecules ; 23(7)2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29932435

RESUMO

Thymus plants are marketed for diverse usages because of their pleasant odor, as well as high nutritional value and wealth of health-promoting phytochemicals. In this study, Thymuszygis, Thymuspulegioides, and Thymusfragrantissimus grown under organic cultivation regime were characterized regarding nutrients and phenolic compounds. In addition, the antioxidant and antibacterial properties of these species were screened. The plants were particularly notable for their high K/Na ratio, polyunsaturated fatty acids content and low omega-6/omega-3 fatty acids ratios, which are valuable features of a healthy diet. Caffeic acid and/or its derivatives, mainly rosmarinic acid and caffeoyl rosmarinic acid, represented the majority of the phenolic constituents of these plants, although they were less representative in T. pulegioides, which in turn was the richest in flavones. The latter species also exhibited the highest antioxidant capacity (DPPH● EC50 of 9.50 ± 1.98 µg/mL and reducing power EC50 of 30.73 ± 1.48 µg/mL), while T. zygis was the most active towards Gram-positive and Gram-negative bacteria. Overall, the results suggest that the three thyme plants grown in organic farming are endowed with valuable metabolites that give them high commercial value for applications in different industries.


Assuntos
Antibacterianos/química , Antioxidantes/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Thymus (Planta)/química , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Ácidos Cafeicos/química , Ácidos Cafeicos/isolamento & purificação , Cinamatos/química , Cinamatos/isolamento & purificação , Depsídeos/química , Depsídeos/isolamento & purificação , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/isolamento & purificação , Ácidos Graxos Ômega-6/química , Ácidos Graxos Ômega-6/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Fenóis/química , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Picratos/antagonistas & inibidores , Extratos Vegetais/farmacologia , Potássio/química , Potássio/isolamento & purificação , Sódio/química , Sódio/isolamento & purificação , Thymus (Planta)/metabolismo , Ácido Rosmarínico
7.
Green Chem ; 19(12): 2768-2773, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-30271269

RESUMO

The ability to induce reversible transitions between homogeneous solutions and biphasic systems is of paramount relevance in separation processes. In this context, pH-triggered aqueous biphasic systems composed of ionic liquids and salts are here disclosed as switchable mono/biphasic systems, and their potential application further demonstrated through an intregated aproach comprising both the production and separation of hydroxymethylfurfural from fructose.

8.
ACS Sustain Chem Eng ; 5(8): 7344-7351, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30271685

RESUMO

Triterpenic acids (TTAs) are well known for their relevant biological properties and have been facing an increasing interest for nutraceutical and pharmaceutical applications. To overcome the concerns associated to the commonly used volatile organic solvents for their extraction from biomass, here we investigate the potential of aqueous solutions of ionic liquids (ILs) as alternative solvents. The solubility of ursolic acid (UA) was firstly determined in several aqueous solutions of ILs (hydrotropes or surface-active) at 30°C to appraise the dissolution phenomenon. Conventional surfactants were also investigated for comparison purposes. The collected data reveal a remarkable enhancement in the solubility of UA (8 orders of magnitude) in surface-active ILs aqueous solutions when compared to pure water. Afterwards, the potential of these ILs aqueous solutions was confirmed by their use in the extraction of TTAs from apple peels. Total extractions yield of TTAs of 2.62 wt.% were obtained using aqueous solutions of surface-active ILs at moderate conditions, overwhelming the extraction yields of 2.48 wt.% obtained with chloroform and 1.37 wt.% with acetone using similar conditions.

9.
Mar Pollut Bull ; 104(1-2): 162-70, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26851871

RESUMO

Seasonal and spatial variations of dissolved and particulate methylmercury were evaluated for the first time in sediment cores from the Tagus Estuary. Results showed the highest MeHg concentrations in summer months indicating that the "seasonally" methylation process occurs not only at the topmost layers of the sediments but also in the deeper layers of the sediment column. The proportion of MeHg (up to 92%) in some of our pore water samples was higher than values reported in the literature for other estuaries suggesting that the sedimentary environment in the Tagus tends to favour Hg methylation. This work points to the importance of seasonal variation of the MeHg production in sediment cores. In physically dominated estuaries this enhances seasonal MeHg production in deeper sediments that can have serious ecological impacts due to resuspension or advection processes under extreme events by the increase of MeHg transported to the water column.


Assuntos
Monitoramento Ambiental/métodos , Estuários , Sedimentos Geológicos/química , Compostos de Metilmercúrio/análise , Estações do Ano , Poluentes Químicos da Água/análise , Substâncias Húmicas/análise , Mercúrio/análise , Portugal
10.
Chem Commun (Camb) ; 50(61): 8363-6, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-24943806

RESUMO

Three phthalocyanines (Pcs) conjugated with α-, ß- and γ-cyclodextrins (CDs) were prepared and their application as photosensitizer (PS) agents was assessed by photophysical, photochemical and in vitro photobiological studies. The photoactivity of Pc-α-CD and Pc-γ-CD ensures their potential as PDT drugs against UM-UC-3 human bladder cancer cells.


Assuntos
Ciclodextrinas/química , Indóis/química , Fármacos Fotossensibilizantes/síntese química , Linhagem Celular , Núcleo Celular/química , Núcleo Celular/patologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Isoindóis , Luz , Microscopia de Fluorescência , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/toxicidade , Neoplasias da Bexiga Urinária/tratamento farmacológico
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