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1.
Planta Med ; 87(12-13): 1018-1024, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33906246

RESUMO

Euphorbia myrsinites is one of the oldest spurges described and used in folk medicine. It is characterized by blue-grey stems similar to myrtle, and it is spread in the Mediterranean region, Asia, and the USA. Chemical analysis of E. myrsinites collected in Turkey afforded the isolation of 4 diterpenes based on the so-called myrsinane skeleton being tetraesters of the tetracyclic diterpene alcohol myrsinol. In this study, the phytochemical analysis of this species collected in Italy has been undertaken to afford the isolation of a new atisane diterpene, named myrsatisane, 3 ingenol derivatives, along with the 4 tetraester derivatives previously found. A triterpene compound based on the euphane skeleton has also been isolated. Structural elucidation of the new myrsatisane was based on spectroscopic techniques, including HR-MS and 1- and 2-dimensional NMR experiments. Its relative configuration was determined by NOE correlations, while absolute stereochemistry was obtained by quantum-mechanical DFT studies. While diterpenes with the atisane skeleton are relatively common in Euphorbia species, this is the first report of an atisane diterpene from E. myrsinites. All the isolated terpenes were tested for anti-inflammatory activity on J774A.1 macrophages stimulated with lipopolysaccharide by evaluation of nitrite and pro-inflammatory cytokine Il-1ß levels. Among tested compounds, the 3 ingenol diterpenes exhibited a dose-dependent (0.001 - 3 µM) significant activity, thus showing their potential as anti-inflammatory drug candidates.


Assuntos
Diterpenos , Euphorbia , Triterpenos , Anti-Inflamatórios/farmacologia , Diterpenos/farmacologia , Estrutura Molecular , Terpenos
2.
J Sci Food Agric ; 101(14): 6010-6019, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33855720

RESUMO

BACKGROUND: Chia (Salvia hispanica L.) is a functional food from Central America. Interest in it is growing rapidly due to the many health benefits from the seed. However, when chia is grown at high latitudes, seed yield may be low whereas a high stem biomass and immature inflorescences are produced. Little is known about the chemical composition and the properties of stems and flowers. In this work, the metabolite profile, the antioxidant activity, and the total polyphenol content of stems and inflorescences were evaluated in a factorial experiment with different chia populations (commercial black chia and long-day flowering mutants G3, G8, and G17) and irrigation (100% and 50% of evapotranspiration). RESULTS: The results show the influence of irrigation and seed source on the antioxidant activity and total polyphenol content of chia flower and stem. Inflorescences exhibit higher antioxidant activity, suggesting their potential use as natural antioxidant. The mutants G3 and G8, at 50% irrigation, contained the highest amounts of compounds with nutraceutical value, especially within the flower. The mutant G17 showed lower antioxidant activity and polyphenol content compared to other seed sources but exhibited high omega 3 content in flowers but low in stems. This indicates that chia varieties should be chosen according to the objective of cultivation. CONCLUSION: These findings, indicating a close relation of metabolite content with irrigation and seed source, may provide the basis for the use of chia flower and stem for their nutraceutical value in the food, feed, and supplement industries. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Antioxidantes/química , Extratos Vegetais/química , Salvia/crescimento & desenvolvimento , Salvia/metabolismo , Irrigação Agrícola , Antioxidantes/metabolismo , América Central , Suplementos Nutricionais/análise , Flores/química , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Metabolômica , Mutação , Extratos Vegetais/metabolismo , Caules de Planta/química , Caules de Planta/genética , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Salvia/química , Salvia/genética , Água/análise , Água/metabolismo
3.
Phytochem Anal ; 32(1): 84-90, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32023359

RESUMO

INTRODUCTION: Cinnamic acids are a class of compounds based on phenyl propanoid backbone (C6-C3) isolated from plants and microorganisms, exhibiting interesting biological activities. OBJECTIVE: To characterise cinnamic acids through the phytochemical study of welsh onion, Allium fistulosum, and to evaluate their antibacterial and cytotoxic properties. MATERIAL AND METHODS: The phytochemical study of A. fistulosum was performed through chromatographic techniques, including reversed phase medium-pressure liquid chromatography (MPLC) and high-pressure liquid chromatography (HPLC). Preliminary analysis of crude chromatographic fractions from the organic extracts was carried out by proton nuclear magnetic resonance (1 H-NMR) in order to prioritise the study of those having phenyl propanoid skeleton. The structural identification of the isolated compounds was performed through analysis of spectroscopic data, mainly one-dimensional (1D) and two-dimensional (2D) NMR. The antibacterial activity was assessed against gram negative (Escherichia coli) and gram positive (Staphylococcus aureus) bacteria while the cytotoxic property was evaluated on breast cancer cell line (MCF-7). RESULTS: The 1 H-NMR study of crude fractions and application of a straightforward method to purify the phenyl propanoid compounds by reversed phase MPLC and HPLC, allowed the effortless isolation of several cinnamic acids, including two new rare phenolic imidates (1 and 2). The use of an entirely NMR approach for structural elucidation of the isolated metabolites allowed the isolated material to be kept for further pharmacological tests. CONCLUSION: These results corroborate the importance of the use of 1D and 2D NMR to the identification of new phenyl propanoids, potential lead compounds against bacteria and cancer cells.


Assuntos
Allium , Antibacterianos/farmacologia , Cinamatos , Testes de Sensibilidade Microbiana , Cebolas , Extratos Vegetais/farmacologia
4.
Trends Food Sci Technol ; 106: 1-11, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32982062

RESUMO

Background: A novel coronavirus, the SARS-CoV2, was revealed to be the cause of COVID19, the pandemic disease that already provoked more than 555.324 deaths in the world (July 10, 2020). No vaccine treatment has been defined against SARS-CoV2 or other human coronaviruses (HCoVs), including those causing epidemic infections, neither appropriate strategies for prevention and care are yet officially suggested. Scope and approach: We reviewed scientific literature on natural compounds that were defined as potentially effective against human coronaviruses. Our desk research identified non-chemically modified natural compounds that were shown (in vitro) and/or predicted (in silico) to act against one or more phases of human coronaviruses cell cycle.We selected all available information, merged and annotated the data to define a comprehensive list of natural compounds, describing their chemical classification, the source, the action, the specific target in the viral infection. Our aim was to collect possible compounds for prevention and care against human coronaviruses. Key findings and conclusions: The definition of appropriate interventions against viral diseases need a comprehensive view on the infection dynamics and on necessary treatments. Viral targeting compounds to be exploited in food sciences could be of relevant interest to this aim.We collected 174 natural compounds showing effects against human infecting coronaviruses, providing a curated annotation on actions and targets.The data are available in anti-HCoV, a web accessible resource to be exploited for testing and in vivo trials. The website is here launched to favour a community based cooperative effort to call for contribution and expand the collection. To be ready to fight.

6.
Phytochem Anal ; 30(5): 556-563, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31286582

RESUMO

INTRODUCTION: Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most devastating and harmful pests of tomato (Solanum lycopersicum) crops causing up to 80-100% yield losses. A large arsenal of plant metabolites is induced by the leafminer feeding including defence compounds that could differ among varieties. OBJECTIVE: To compare the metabolomic changes of different genotypes of tomato (tolerant "T", susceptible "S" and "F1" hybrid obtained between T and S) after exposition to T. absoluta. METHODOLOGY: Nuclear magnetic resonance (NMR) spectroscopy followed by multivariate data analysis were performed to analyse the metabolic profiles of control and infested samples on three different tomato genotypes. RESULTS: Signals related to GABA (γ-aminobutyric acid) were relatively much higher in all infested samples compared to the non-infested plants used as control. Infested T genotype samples were the most abundant in organic acids, including fatty acids and acyl sugars, chlorogenic acid, neo-chlorogenic acid and feruloyl quinic acid, indicating a clear link between the exposure to leafminer. Results also showed an increase of trigonelline in all tomato varieties after exposition to T. absoluta. CONCLUSION: Metabolomics approach based on NMR spectroscopy followed by multivariate data analysis allowed for a detailed metabolite profile of plant defences, providing fundamental information for breeding programmes in plant crops.


Assuntos
Lepidópteros/fisiologia , Lycopersicon esculentum/parasitologia , Espectroscopia de Ressonância Magnética/métodos , Metabolômica , Animais , Comportamento Alimentar , Genes de Plantas , Lycopersicon esculentum/genética , Análise Multivariada
8.
Phytochem Anal ; 30(5): 535-546, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31177603

RESUMO

INTRODUCTION: The phytoalimurgic plants, common dandelion (Taraxacum officinale), corn poppy (Papaver rhoeas) and stinging nettle (Urtica dioica) are a source of nutraceuticals. OBJECTIVES: To apply a combined metabolomic fingerprinting approach by nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS) to common dandelion, corn poppy and stinging nettles to obtain simultaneous identification and quantitation of the major classes of organic compounds. METHODOLOGY: The whole plants collected in the Cilento National Park were dried and then extracted to obtain non-polar and polar organic extracts. GC-MS was used for non-polar extracts while 1 H-NMR spectroscopy was used for polar extracts. In both cases, simultaneous identification and quantification of the bioactive metabolites was obtained. RESULTS: Non-polar organic extracts of all plants were mainly composed of palmitic, stearic and oleic acids. The two pentacyclic triterpenols α- and ß-amyrin were detected in nettle extract. The analysis of polar organic extracts allowed to detect and quantify organic acids and sugars as main metabolites along with amino acids, caffeoyl derivatives, flavonoids, and nucleotides. In particular, corn poppy leaves contained a huge amount of glyceric acid (55.7% of the total extract). Stinging nettles, instead, exhibited a large amount of choline (19.5%). CONCLUSION: Metabolomic approach coupling GC-MS with NMR spectroscopy allowed to provide a detailed metabolite profile of three alimurgic plants, common dandelion, corn poppy and stinging nettle, from both a qualitative and quantitative point of view.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética/métodos , Metabolômica , Papaver/metabolismo , Taraxacum/metabolismo , Urtica dioica/metabolismo , Extratos Vegetais/química
9.
Mar Drugs ; 17(2)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717102

RESUMO

The saponin composition of a specimen of black sea cucumber, Holothuria atra collected in the Persian Gulf was studied by a combined approach including LC-MS/MS, Molecular Networking, pure compound isolation, and NMR spectroscopy. The saponin composition of Holothuria atra turned out to be more complex than previously reported. The most abundant saponins in the extract (1⁻4) were isolated and characterized by 1D- and 2D-NMR experiments. Compound 1 was identified as a new triterpene glycoside saponin, holothurin A5. The side chain of the new saponin 1, unprecedented among triterpene glycosides, is characterized by an electrophilic enone function, which can undergo slow water or methanol addition under neutral conditions. The cytotoxic activity of compounds 1⁻4, evaluated on the human cervix carcinoma HeLa cell line, was remarkable, with IC50 values ranging from 1.2 to 2.5 µg/mL.


Assuntos
Citotoxinas/química , Holothuria/química , Saponinas/química , Animais , Mar Negro , Citotoxinas/toxicidade , Células HeLa , Humanos , Oceano Índico , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oligossacarídeos , Saponinas/isolamento & purificação , Saponinas/toxicidade , Espectrometria de Massas em Tandem , Triterpenos/química
10.
Food Chem ; 254: 137-143, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29548434

RESUMO

Chia is a food plant producing seeds which have seen increasing interest owing to their health benefits. This work is the first report on the metabolite profile, total polyphenols and antioxidant activity of chia seeds, determined by ultrasound-assisted extraction, coupled with gas chromatography-mass spectrometry (UAE GC-MS). Different chia sources were compared: two commercial (black and white) and three early flowering (G3, G8 and G17) mutant genotypes. Organic extracts were mainly composed of mono- and polyunsaturated fatty acids with alpha-linolenic being the most abundant. Polar extracts contained sucrose, methylgalactoside and glucose as main sugars. Antioxidant activity and total polyphenolic content were correlated. Chemical composition and yield potential of early flowering genotypes were different from commercial chia, and while white chia showed the highest content of omega-3 fatty acids, the high content of nutraceuticals in G17 and G8 suggests them as a potential source of raw materials for the food/feed industry.


Assuntos
Antioxidantes/análise , Metabolômica , Mutação , Salvia/química , Sementes/química , Sementes/genética , Suplementos Nutricionais/análise , Ácidos Graxos/análise , Ácidos Graxos Ômega-3/química , Ácidos Graxos Insaturados/análise , Cromatografia Gasosa-Espectrometria de Massas , Genótipo , Açúcares/análise , Ultrassom
11.
Ecology ; 99(1): 158-171, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29065230

RESUMO

Litter burning and biological decomposition are oxidative processes co-occurring in many terrestrial ecosystems, producing organic matter with different chemical properties and differently affecting plant growth and soil microbial activity. We tested the chemical convergence hypothesis, i.e., materials with different initial chemistry converge toward a common profile, with similar biological effects, as the oxidative process advances, for burning and decomposition. We compared the molecular composition, assessed by 13 C NMR, of seven plant litter types either fresh, decomposed for 30, 90, 180 d in a microcosms incubation experiment, or heated at 100°C, 200°C, 300°C, 400°C, 500°C for 30 minutes. We used litter water extracts (5% dry weight) as treatments in bioassays on plant (Lepidium sativum) and fungal (Aspergillus niger) growth, and a washed quartz sand amended with litter (0.5% dw) to assess heterotrophic respiration by flux chamber (i.e., [µg of CO2 released]·[g added litter]-1 ·d-1 ). We observed different molecular variations for materials either burning (i.e., a sharp increase of aromatic C and a decrease of other fractions above 200°C) or decomposing (i.e., early increase of alkyl, methoxyl, and N-alkyl C and decrease of O-alkyl and di-O-alkyl C fractions). Soil respiration and fungal growth decreased with litter age and heating severity, down to 20% relative to fresh litter. Plants were inhibited on fresh litter (on average 13% of the control), but recovered on aged (180 d) and heated (30 min at 500°C) materials, up to 126% and 63% of the control, respectively. Correlation between the intensity of 13 C NMR signals in litter spectra and bioassay results showed that O-alkyl, methoxyl, and aromatic C fractions are crucial to understand organic matter effects, with plant response negatively affected by labile C but positively associated to lignification and pyrogenic C. The pattern of association of soil respiration and fungal growth to these C fractions was essentially opposite to that observed for plant root growth. Our findings suggest a functional convergence of decomposed and burned organic substrates, emerging from the balance between the bioavailability of labile C sources and the presence of recalcitrant and pyrogenic compounds, oppositely affecting different trophic levels.


Assuntos
Ecossistema , Plantas , Carbono , Fungos , Desenvolvimento Vegetal , Solo/química
12.
Nat Prod Res ; 31(18): 2119-2125, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28105862

RESUMO

Mushrooms produce a wide range of bioactive polysaccharides, different from each other in chemical structure and biological effects. In the last years, the idea to develop functional foods or drugs containing fungal polysaccharides is attracting great attention. Fruiting bodies of Basidiomycetes Ganoderma lucidum are commonly used in Oriental medicine to treat several disorders. G. lucidum polysaccharides - mainly ß-glucans and heteroglycans - have numerous biological properties such as antitumour and immunomodulatory activities. This report shows, by gene expression analyses and bioenergetic assays, immunomodulatory properties and capacity to improve glucose metabolism of a water-soluble heteroglycan extracted from mycelium of an Italian isolate of G. lucidum. The findings suggest the use of the heteroglycan as probiotic or ingredient in functional foods, being easy to produce and disperse in a food matrix thanks to its water-solubility. Heteroglycan could exert protective effects in pro-inflammatory conditions and benefits for people characterised by suppressed immune response.


Assuntos
Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Glucanos/farmacologia , Fatores Imunológicos/farmacologia , Reishi/química , Linhagem Celular , Citocinas/genética , Avaliação Pré-Clínica de Medicamentos/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Glucanos/química , Glucose/metabolismo , Humanos , Fatores Imunológicos/química , Itália , Espectroscopia de Ressonância Magnética , Medicina Tradicional do Leste Asiático , Micélio/química , Solubilidade , Água
13.
Planta Med ; 82(18): 1584-1590, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27852096

RESUMO

An extensive phytochemical analysis of the polar extracts from bulbs of Welsh onion Allium fistulosum L. led to the isolation of nine saponins, four of them, named fistulosaponins G (1a/1b), H (2), I (3a/3b), and J (4), have never been reported previously. Fistulosaponins G and I were isolated as a couple of isomers in equilibrium. On the basis of 2D NMR and mass spectrometry data, the structure of the novel compounds were elucidated as (25R)-26-[(ß-D-glucopyranosyl)oxy]-3ß,22ß-dihydroxyfurost-5-en-1ß-yl O-α-L-rhamnopyranosyl-(1 → 4)-O-α-L-rhamnopyranosyl-(1 → 4)-ß-D-glucopyranoside (1a) with its 22α epimer (1b), (25R)-26-[(ß-D-glucopyranosyl)oxy]-3ß-hydroxyfurost-5,20-dien-1ß-yl O-α-L-rhamnopyranosyl-(1 → 4)-O-α-L-rhamnopyranosyl-(1 → 4)-ß-D-glucopyranoside (2), (25R)-26-[(ß-D-glucopyranosyl)oxy]-3ß,22ß-dihydroxyfurost-5-en-1ß-yl O-α-L-rhamnopyranosyl-(1 → 4)-ß-D-glucopyranoside (3a) with its 22α epimer (3b), and (25R)-26-[(ß-D-glucopyranosyl)oxy]-3ß-hydroxyfurost-5,20-dien-1ß-yl O-α-L-rhamnopyranosyl-(1 → 4)-ß-D-glucopyranoside (4). This is the first report of furostanol saponins in A. fistulosum bulbs. In addition, data on the antibacterial tests of the isolated saponins against Escherichia coli and Enterococcus faecalis are reported.


Assuntos
Allium/química , Antibacterianos/química , Saponinas/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Saponinas/isolamento & purificação , Saponinas/farmacologia
14.
Phytochem Anal ; 27(5): 304-14, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27437863

RESUMO

INTRODUCTION: Globe artichoke (Cynara cardunculus L. var. scolymus L. Fiori) and cardoon (Cynara cardunculus L. var. altilis DC) are sources of nutraceuticals and bioactive compounds. OBJECTIVES: To apply a NMR metabolomic fingerprinting approach to Cynara cardunculus heads to obtain simultaneous identification and quantitation of the major classes of organic compounds. METHODOLOGY: The edible part of 14 Globe artichoke populations, belonging to the Romaneschi varietal group, were extracted to obtain apolar and polar organic extracts. The analysis was also extended to one species of cultivated cardoon for comparison. The (1) H-NMR of the extracts allowed simultaneous identification of the bioactive metabolites whose quantitation have been obtained by spectral integration followed by principal component analysis (PCA). RESULTS: Apolar organic extracts were mainly based on highly unsaturated long chain lipids. Polar organic extracts contained organic acids, amino acids, sugars (mainly inulin), caffeoyl derivatives (mainly cynarin), flavonoids, and terpenes. The level of nutraceuticals was found to be highest in the Italian landraces Bianco di Pertosa zia E and Natalina while cardoon showed the lowest content of all metabolites thus confirming the genetic distance between artichokes and cardoon. CONCLUSION: Metabolomic approach coupling NMR spectroscopy with multivariate data analysis allowed for a detailed metabolite profile of artichoke and cardoon varieties to be obtained. Relevant differences in the relative content of the metabolites were observed for the species analysed. This work is the first application of (1) H-NMR with multivariate statistics to provide a metabolomic fingerprinting of Cynara scolymus. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Metabolômica , Espectroscopia de Prótons por Ressonância Magnética/métodos , Aminoácidos/análise , Carboidratos/análise , Flavonoides/análise , Análise Multivariada , Polifenóis/análise , Análise de Componente Principal
15.
Steroids ; 115: 90-97, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27474490

RESUMO

From the aerial parts of Euphorbia sogdiana Popov, obtusifoliol (1) and two related steroids (2-3) have been isolated and characterized along with a known cycloartane derivative (4). The chemical structure of the obtusifoliol-related compounds, obtained by 1D and 2D NMR, and MS measurements, have been determined as: 3ß,7α-dihydroxy-4α,14α-dimethyl-5α-ergosta-8,24(28)-diene-11-one (2) and 3ß-hydroxy-4α,14α-dimethyl-5α-ergosta-8,24(28)-diene-1-one (3). Compound 2 has been previously isolated from Euphorbia chamaesyce while compound 3 was never reported before. The isolated compounds 1-4 were subjected to cytotoxic tests on the breast cancer cells, MCF-7 and MDA-MB231. Further pharmacological tests on the more active compounds 2 and 3 indicated their action to be related to cell growth inhibitory activity and apoptotic effects on the tested cells.


Assuntos
Colestadienóis/química , Euphorbia/química , Esteroides/química , Esteroides/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética , Estrutura Molecular
16.
Fitoterapia ; 108: 87-92, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26586622

RESUMO

Phytochemical analysis of Euphorbia sogdiana Popov, Euphorbiaceae, afforded the isolation of three new diterpenes based on the rare 6(17)-epoxylathyrane skeleton (1-3), along with a lathyrane (4), a myrsinane (5) and a tigliane (6) diterpenoids, previously isolated from Euphorbia aellenii. Their chemical structures were established through a combination of nuclear magnetic resonance spectroscopy and mass spectrometric methods. The epoxylathyranes 1-4 were tested to evaluate their cytotoxic activity against Jurkat T-leukemia and EJ-138 bladder cancer cells and their chemical analogy allowed to propose some structure activity relationships.


Assuntos
Antineoplásicos Fitogênicos/química , Diterpenos/química , Euphorbia/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Diterpenos/isolamento & purificação , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
17.
Fitoterapia ; 104: 75-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26003936

RESUMO

From the whole plant of Euphorbia cyparissias, two new diterpenes based on jatrophane skeleton, named cyparissins A and B (1 and 2) were isolated. Their chemical structures were established through a combination of nuclear magnetic resonance spectroscopy and mass spectrometric methods. The new cyparissins A and B were tested to evaluate their ability to inhibit P-glycoprotein-mediated multidrug resistance and their cytotoxic activity against A2780 human ovarian cancer cells, both WT and ADR. Compounds 1 and 2 showed moderate inhibitory effects on P-glycoprotein while showing a significant concentration-depending cytotoxic activity for both cancer cell lines. These isolated compounds are based on a new chemical structure that expands the knowledge base for this class of bioactive metabolites.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Diterpenos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Euphorbia/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Feminino , Humanos , Estrutura Molecular , Neoplasias Ovarianas/patologia
18.
Phytochemistry ; 115: 216-21, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25725962

RESUMO

A chalconoid analogue, 1,3,5-benzentriol 2-[(2S,3R)-3-(3,4-dihydroxylphenyl)-2,3-dihydroxylpropyl], named filiferol (1), has been isolated and purified for the first time from the leaf basal tissues of the palm species Washingtonia filifera. The chemical structure of the isolated compound has been elucidated unambiguously by spectroscopic and chemical methods. Filiferol has been based on a flavonol structure with the reduction of the common flavonoid keto group to give an unprecedented methylene carbon on the three carbon chain. An analogous compound with S stereochemistry at C3 has been obtained as synthetic intermediate for developing an enantioselective synthesis of (2R,3S)-(+)-catechin. Even though 1 proved to be deprived of antifungal properties, it displays a very effective larvicidal activity against Red Palm Weevil, Rhynchophorus ferrugineus, an important pest affecting cultivated and ornamental palms. 1 has been isolated from leaf tissues of W. filifera, a species resistant to this pest, but this molecule seems instead undetectable in tissues of other palm species susceptible to the parasite. The presence of 1 could therefore account for W. filifera natural resistance to the attacks of the Red Palm Weevil (R. ferrugineus).


Assuntos
Arecaceae/química , Chalconas/isolamento & purificação , Chalconas/farmacologia , Inseticidas/isolamento & purificação , Inseticidas/farmacologia , Animais , Chalconas/química , Inseticidas/química , Larva/efeitos dos fármacos , Estrutura Molecular , Gorgulhos/efeitos dos fármacos
19.
PLoS One ; 10(1): e0117393, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25625643

RESUMO

Cigarette butts (CBs) are the most common type of litter on earth, with an estimated 4.5 trillion discarded annually. Apart from being unsightly, CBs pose a serious threat to living organisms and ecosystem health when discarded in the environment because they are toxic to microbes, insects, fish and mammals. In spite of the CB toxic hazard, no studies have addressed the effects of environmental conditions on CB decomposition rate. In this study we investigate the interactive effects of substrate fertility and N transfer dynamics on CB decomposition rate and carbon quality changes. We carried out an experiment using smoked CBs and wood sticks, used as a slow decomposing standard organic substrate, incubated in both laboratory and field conditions for two years. CB carbon quality changes during decomposition was assessed by 13C CPMAS NMR. Our experiment confirmed the low degradation rate of CBs which, on average, lost only 37.8% of their initial mass after two years of decomposition. Although a net N transfer occurred from soil to CBs, contrary to our hypothesis, mass loss in the medium-term (two years) was unaffected by N availability in the surrounding substrate. The opposite held for wood sticks, in agreement with the model that N-rich substrates promote the decomposition of other N-poor natural organic materials with a high C/N ratio. As regards CB chemical quality, after two years of decomposition 13C NMR spectroscopy highlighted very small changes in C quality that are likely to reflect a limited microbial attack.


Assuntos
Resíduos Perigosos/análise , Produtos do Tabaco/análise , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Meia-Vida , Nitrogênio/análise
20.
New Phytol ; 206(1): 127-132, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25628124

RESUMO

Self-inhibition of growth has been observed in different organisms, but an underlying common mechanism has not been proposed so far. Recently, extracellular DNA (exDNA) has been reported as species-specific growth inhibitor in plants and proposed as an explanation of negative plant-soil feedback. In this work the effect of exDNA was tested on different species to assess the occurrence of such inhibition in organisms other than plants. Bioassays were performed on six species of different taxonomic groups, including bacteria, fungi, algae, plants, protozoa and insects. Treatments consisted in the addition to the growth substrate of conspecific and heterologous DNA at different concentration levels. Results showed that treatments with conspecific DNA always produced a concentration dependent growth inhibition, which instead was not observed in the case of heterologous DNA. Reported evidence suggests the generality of the observed phenomenon which opens new perspectives in the context of self-inhibition processes. Moreover, the existence of a general species-specific biological effect of exDNA raises interesting questions on its possible involvement in self-recognition mechanisms. Further investigation at molecular level will be required to unravel the specific functioning of the observed inhibitory effects.


Assuntos
Arabidopsis/genética , DNA/farmacologia , Plantas/efeitos dos fármacos , Sarcofagídeos/efeitos dos fármacos , Animais , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Ecossistema , Espaço Extracelular/genética , Physarum polycephalum/efeitos dos fármacos , Physarum polycephalum/crescimento & desenvolvimento , Sarcofagídeos/crescimento & desenvolvimento , Scenedesmus/efeitos dos fármacos , Scenedesmus/crescimento & desenvolvimento , Solo , Especificidade da Espécie , Trichoderma/efeitos dos fármacos , Trichoderma/crescimento & desenvolvimento
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