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1.
Food Chem ; 373(Pt B): 131452, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34731792

RESUMO

With a favored taste and various bioactivities, coffee has been consumed as a daily beverage worldwide. The current study presented a multi-faceted comparative metabolomics approach dissecting commercially available coffee products in the Middle East region for quality assessment and functional food purposes using NMR and GC/MS platforms. NMR metabolites fingerprinting led to identification of 18 metabolites and quantification (qNMR) of six prominent markers for standardization purposes. An increase of ß-ethanolamine (MEA) reported for the first time, 5-(hydroxymethyl) furfural (5-HMF), concurrent with a reduction in chlorogenic acid, kahweol, and sucrose levels post roasting as revealed using multivariate data analyses (MVA). The diterpenes kahweol and cafestol were identified in green and roasted Coffea arabica, while 16-O-methyl cafestol in roasted C. robusta. Moreover, GC/MS identified a total of 143 metabolites belonging to 15 different chemical classes, with fructose found enriched in green C. robusta versus fatty acids abundance, i.e., palmitic and stearic acids in C. arabica confirming NMR results. These potential results aided to identify novel quality control attributes, i.e., ethanolamine, for coffee in the Middle East region and have yet to be confirmed in other coffee specimens.


Assuntos
Coffea , Café , Cromatografia Gasosa-Espectrometria de Massas , Genótipo , Temperatura Alta , Metaboloma
2.
Molecules ; 26(6)2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33800987

RESUMO

Phytochemical investigation of the methanolic extract obtained from the aerial parts of Lagochilus setulosus (Lamiaceae) afforded the new compound 1-methoxy-3-O-ß-glucopyranosyl-α-l-oliose (1) together with five known glycosides, namely sitosterol-3-O-ß-glucoside (2), stigmasterol-3-O-ß-glucoside (3), pinitol (4), 6ß-hydroxyl-7-epi-loganin (5), and chlorotuberoside (6). The structures of these compounds were elucidated by extensive spectroscopic analyses, especially HR-MS, 1D and 2D NMR spectroscopy. The in vitro cytotoxic activity of the methanolic extract and the isolated compounds was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and crystal violet (CV) staining assays. In addition, the antifungal activities of the components were evaluated against Botrytis cinerea, Septoria tritici, and Phytophthora infestans. The anthelmintic potential was determined against Caenorhabditis elegans nematodes. Neither the extract nor the isolated compounds showed promising activity in all the bioassays.


Assuntos
Anti-Helmínticos , Antifúngicos , Glicosídeos , Lamiaceae/química , Extratos Vegetais/química , Animais , Anti-Helmínticos/química , Anti-Helmínticos/isolamento & purificação , Anti-Helmínticos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Ascomicetos/crescimento & desenvolvimento , Botrytis/crescimento & desenvolvimento , Caenorhabditis elegans/crescimento & desenvolvimento , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Phytophthora infestans/crescimento & desenvolvimento
3.
Plant J ; 105(5): 1309-1325, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33617106

RESUMO

Secretions from glandular trichomes potentially protect plants against a variety of aggressors. In the tomato clade of the Solanum genus, glandular trichomes of wild species produce a rich source of chemical diversity at the leaf surface. Previously, 7-epi-zingiberene produced in several accessions of Solanum habrochaites was found to confer resistance to whiteflies (Bemisia tabaci) and other insect pests. Here, we report the identification and characterisation of 9-hydroxy-zingiberene (9HZ) and 9-hydroxy-10,11-epoxyzingiberene (9H10epoZ), two derivatives of 7-epi-zingiberene produced in glandular trichomes of S. habrochaites LA2167. Using a combination of transcriptomics and genetics, we identified a gene coding for a cytochrome P450 oxygenase, ShCYP71D184, that is highly expressed in trichomes and co-segregates with the presence of the zingiberene derivatives. Transient expression assays in Nicotiana benthamiana showed that ShCYP71D184 carries out two successive oxidations to generate 9HZ and 9H10epoZ. Bioactivity assays showed that 9-hydroxy-10,11-epoxyzingiberene in particular exhibits substantial toxicity against B. tabaci and various microorganisms including Phytophthora infestans and Botrytis cinerea. Our work shows that trichome secretions from wild tomato species can provide protection against a wide variety of organisms. In addition, the availability of the genes encoding the enzymes for the pathway of 7-epi-zingiberene derivatives makes it possible to introduce this trait in cultivated tomato by precision breeding.


Assuntos
Hemípteros/metabolismo , Sesquiterpenos Monocíclicos/metabolismo , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Solanum/metabolismo , Animais , Botrytis/efeitos dos fármacos , Botrytis/patogenicidade , Hemípteros/genética , Hemípteros/microbiologia , Sesquiterpenos Monocíclicos/toxicidade , NADPH-Ferri-Hemoproteína Redutase/genética , Phytophthora infestans/efeitos dos fármacos , Phytophthora infestans/patogenicidade , Solanum/genética
4.
Molecules ; 25(21)2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158186

RESUMO

1H-NMR is a very reproducible spectroscopic method and, therefore, a powerful tool for the metabolomic analysis of biological samples. However, due to the high complexity of natural samples, such as plant extracts, the evaluation of spectra is difficult because of signal overlap. The new NMR "Pure Shift" methods improve spectral resolution by suppressing homonuclear coupling and turning multiplets into singlets. The PSYCHE (Pure Shift yielded by Chirp excitation) and the Zangger-Sterk pulse sequence were tested. The parameters of the more suitable PSYCHE experiment were optimized, and the extracts of 21 Hypericum species were measured. Different evaluation criteria were used to compare the suitability of the PSYCHE experiment with conventional 1H-NMR. The relationship between the integral of a signal and the related bin value established by linear regression demonstrates an equal representation of the integrals in binned PSYCHE spectra compared to conventional 1H-NMR. Using multivariate data analysis based on both techniques reveals comparable results. The obtained data demonstrate that Pure Shift spectra can support the evaluation of conventional 1H-NMR experiments.


Assuntos
Hypericum/metabolismo , Metaboloma , Metabolômica , Ressonância Magnética Nuclear Biomolecular
5.
Planta Med ; 86(12): 858-866, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32483774

RESUMO

Dalbergia monetaria is an Amazonian plant whose bark is widely used to treat urinary tract infections. This paper describes a bio-guided study of ethanolic extracts from the bark and leaves of D. monetaria, in a search for metabolites active against human pathogenic bacteria. In vitro assays were performed against 10 bacterial strains, highlighting methicillin-sensitive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. Fractioning of the extracts was performed using instrumental and classical techniques, and samples were characterized by UHPLC-HRMS/MS. Ethyl acetate fractions from bark and leaves showed similar antibacterial activities. EAFB is enriched in isoflavone C-glucosides and EAFL enriched in proanthocyanidins. Subfractions from EAFL presented higher activity and showed a complex profile of proanthocyanidins constructed by (epi)-cassiaflavan and (epi)-catechin units, including dimers, trimers and tetramers. The fragmentation pattern emphasized the neutral loss of cassiaflavan units by quinone-methide fission. Fraction SL7-6, constituted by (ent)-cassiaflavan-(ent)-cassiaflavan-(epi)-catechin isomers, showed the lowest MIC against the S. aureus and P. aeruginosa with values corresponding to 64 and 32 µg/mL, respectively. Cassiaflavan-proanthocyanidins have not been found previously in another botanical genus, except in Cassia, and the traditional medicinal use of D. monetaria might be related to the antibacterial activity of proanthocyanidins characterized in the species.


Assuntos
Dalbergia , Staphylococcus aureus Resistente à Meticilina , Plantas Medicinais , Proantocianidinas , Antibacterianos , Cromatografia Líquida de Alta Pressão , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais , Staphylococcus aureus
6.
Metabolomics ; 15(5): 80, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-31087208

RESUMO

INTRODUCTION: The demand to develop efficient and reliable analytical methods for the quality control of nutraceuticals is on the rise, together with an increase in the legal requirements for safe and consistent levels of its active principles. OBJECTIVE: To establish a reliable model for the quality control of widely used Senna preparations used as laxatives and assess its phyto-equivalency. METHODS: A comparative metabolomics approach via NMR and MS analyses was employed for the comprehensive measurement of metabolites and analyzed using chemometrics. RESULTS: Under optimized conditions, 30 metabolites were simultaneously identified and quantified including anthraquinones, bianthrones, acetophenones, flavonoid conjugates, naphthalenes, phenolics, and fatty acids. Principal component analysis (PCA) was used to define relative metabolite differences among Senna preparations. Furthermore, quantitative 1H NMR (qHNMR) was employed to assess absolute metabolites levels in preparations. Results revealed that 6-hydroxy musizin or tinnevellin were correlated with active metabolites levels, suggesting the use of either of these naphthalene glycosides as markers for official Senna drugs authentication. CONCLUSION: This study provides the first comparative metabolomics approach utilizing NMR and UPLC-MS to reveal for secondary metabolite compositional differences in Senna preparations that could readily be applied as a reliable quality control model for its analysis.


Assuntos
Metabolômica , Senosídeos/metabolismo , Acetofenonas/metabolismo , Antracenos/metabolismo , Antraquinonas/metabolismo , Flavonoides/metabolismo , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Naftalenos/metabolismo , Fenóis/metabolismo , Análise de Componente Principal , Controle de Qualidade , Senosídeos/química
7.
Anticancer Agents Med Chem ; 18(10): 1405-1416, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29542423

RESUMO

BACKGROUND: P. mucronata (Pm) comes from South America, Brazil and is characterized as "Maracujá de Restinga". It is used in folk medicine for its soothing properties and in treating insomnia. OBJECTIVE: The present study for the first time analyzed the antioxidant and cytotoxicity of the hydroalcoholic leaves extract and fractions from Pm. METHOD: The cytotoxicity test will be evaluated by different assays (MTT and CV) against human prostate cancer (PC3) and mouse malignant melanoma (B16F10) cell lines, and the antioxidant test by DPPH method. RESULTS: ß-Amyrin, oleanolic acid, ß-sitosterol and stigmasterol were isolated of the most active, hexane fraction. These substances were tested against the tumor cell lines: ß-sitosterol and stigmasterol showed the most relevant activity to PC3 in CV assay and, oleanolic acid to B16F10 by the MTT assay. In addition, it was possible to indicate that the mode of cell death for stigmasterol, presumably is apoptosis. In terms of antioxidant activity, the hydroalcoholic leaves extract presented higher activity (EC50 133.3 µg/mL) compared to the flower (EC50 152.3 µg/mL) and fruit (EC50 207.9 µg/mL) extracts. By the HPLC-MS, it was possible to identify the presence of flavones in the leaf extract (isoschaftoside, schaftoside, isovitexin, vitexin, isoorientin, orientin). CONCLUSIONS: P. mucronata hexane fraction showed promising cytotoxic effect against cancer cell lines, and stigmasterol contributes to this activity, inducing apoptosis of these cells. Furthermore, as other Passiflora species, Pm extract showed antioxidant activity and flavones are its major phenolic compounds.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Passiflora/química , Extratos Vegetais/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Humanos , Camundongos , Conformação Molecular , Fitosteróis/química , Fitosteróis/isolamento & purificação , Fitosteróis/farmacologia , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
8.
Food Chem ; 250: 236-244, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29412917

RESUMO

Roselle (Hibiscus sabdariffa) is a functional food with potential health benefits, consumed either as hot or cold beverage. To ensure quality control of its various products, accurate measurement of active metabolites is warranted. Herein, we propose a combination of ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) and nuclear magnetic resonance (NMR) analytical platforms for the untargeted characterization of metabolites in two roselle cultivars, Aswan and Sudan-1. The analyses revealed 33 metabolites, including sugars, flavonoids, anthocyanins, phenolic and aliphatic organic acids. Their relative contents in cultivars were assessed via principle component analysis (PCA) and orthogonal projection to latent structures analysis (OPLS). Impact of the different extraction methods (decoction, infusion and maceration) was compared by quantitative 1H NMR spectroscopy, revealing cold maceration to be optimal for preserving anthocyanins, whereas infusion was more suited for recovering organic acids. The metabolite pattern revealed by the different extraction methods was found in good correlation for their ability to inhibit α-glucosidase enzyme.


Assuntos
Inibidores de Glicosídeo Hidrolases/química , Hibiscus/química , Extratos Vegetais/química , Antocianinas/análise , Antocianinas/isolamento & purificação , Bebidas/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonoides/isolamento & purificação , Alimento Funcional/análise , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Sudão , Temperatura , alfa-Glucosidases/química
9.
J Agric Food Chem ; 65(8): 1507-1517, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28118713

RESUMO

Ceramides (Cers) are major components of the outermost layer of the skin, the stratum corneum, and play a crucial role in permeability barrier functions. Alterations in Cer composition causing skin diseases are compensated with semisynthetic skin-identical Cers. Plants constitute new resources for Cer production as they contain glucosylceramides (GluCers) as major components. GluCers were purified from industrial waste plant materials, apple pomace (Malus domestica), wheat germs (Triticum sp.), and coffee grounds (Coffea sp.), with GluCer contents of 28.9 mg, 33.7 mg, and 4.4 mg per 100 g of plant material. Forty-five species of GluCers (1-45) were identified with different sphingoid bases, saturated or monounsaturated α-hydroxy fatty acids (C15-28), and ß-glucose as polar headgroup. Three main GluCers were hydrolyzed by a recombinant human glucocerebrosidase to produce phyto-Cers (46-48). These studies showed that rare and expensive phyto-Cers can be obtained from industrial food plant residues.


Assuntos
Ceramidas/química , Coffea/química , Malus/química , Extratos Vegetais/química , Triticum/química , Resíduos/análise , Ceramidas/isolamento & purificação , Análise de Alimentos , Estrutura Molecular , Extratos Vegetais/isolamento & purificação
10.
Fitoterapia ; 112: 229-32, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27316978

RESUMO

Pyrofomins A-D, four polyoxygenated sesquiterpenoids have been isolated from the methanolic extract of the fruit bodies of Pyrofomes demidoffii. Their structures are elucidated by IR, HR-FTICR-MS, and 2D NMR spectroscopy. Furthermore, the cedrane carbon skeleton of pyrofomin A (1) is confirmed by X-ray crystallographic analysis. The sesquiterpenoids 1-4 show neither cytotoxicity against KB cells nor antimicrobial activity.


Assuntos
Polyporaceae/química , Sesquiterpenos/química , Linhagem Celular Tumoral , Carpóforos/química , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Sesquiterpenos/isolamento & purificação
11.
J Nat Prod ; 79(4): 743-53, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-26950610

RESUMO

The chemical investigation of the chloroform extract of Hypericum lanceolatum guided by (1)H NMR, ESIMS, and TLC profiles led to the isolation of 11 new tricyclic acylphloroglucinol derivatives, named selancins A-I (1-9) and hyperselancins A and B (10 and 11), along with the known compound 3-O-geranylemodin (12), which is described for a Hypericum species for the first time. Compounds 8 and 9 are the first examples of natural products with a 6-acyl-2,2-dimethylchroman-4-one core fused with a dimethylpyran unit. The new compounds 1-9 are rare acylphloroglucinol derivatives with two fused dimethylpyran units. Compounds 10 and 11 are derivatives of polycyclic polyprenylated acylphloroglucinols related to hyperforin, the active component of St. John's wort. Their structures were elucidated by UV, IR, extensive 1D and 2D NMR experiments, HRESIMS, and comparison with the literature data. The absolute configurations of 5, 8, 10, and 11 were determined by comparing experimental and calculated electronic circular dichroism spectra. Compounds 1 and 2 were synthesized regioselectively in two steps. The cytotoxicity of the crude extract (88% growth inhibition at 50 µg/mL) and of compounds 1-6, 8, 9, and 12 (no significant growth inhibition up to a concentration of 10 mM) against colon (HT-29) and prostate (PC-3) cancer cell lines was determined. No anthelmintic activity was observed for the crude extract.


Assuntos
Antineoplásicos Fitogênicos , Floroglucinol , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Camarões , Células HT29 , Humanos , Hypericum/química , Masculino , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Floroglucinol/análogos & derivados , Floroglucinol/síntese química , Floroglucinol/química , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologia , Estereoisomerismo , Terpenos
12.
Nat Prod Commun ; 11(12): 1821-1824, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30508342

RESUMO

Four new 19-residue peptaibols, named tulasporins A-D (1-4), were isolated from the semi-solid cultures of Sepedonium tulasneanum. Their structures were elucidated on the basis of extensive ESI-HRMS(n) fragmentation studies as well as (1)H NMR spectroscopic analyses. Interestingly, the structures of tulasporins A-D (1-4) resemble those of chrysospermins isolated earlier from cultures of S. chrysospermur. Previously, it was hypothesized that the peptaibol production by Sepedonium species correlates with the morphology of the aleurioconidia, as exclusively round-shaped aleurioconidia forming species produced peptaibols. Since the investigated Sepedonium tulasneanum produces oval aleurioconidia, this study can be considered as the first report of peptaibols from a Sepedonium strain with oval-shaped aleurioconidia. Thus, it could be demonstrated that both round as well as oval aleurioconidia forming Sepedonium species are able to produce peptaibols. Tulasporins A-D (1-4), when tested against phytopathogenic fungi, exhibited good growth inhibitory activity against both Botrytis cinerea and Phytophthora infestans, while they were devoid of significant activity against Septoria tritici.


Assuntos
Hypocreales/química , Peptaibols/isolamento & purificação , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Peptaibols/química , Peptaibols/farmacologia , Phytophthora/efeitos dos fármacos , Phytophthora/crescimento & desenvolvimento , Espectrometria de Massas por Ionização por Electrospray
13.
Bioorg Med Chem ; 23(19): 6327-34, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26358281

RESUMO

From the ethno-medicinally used leaves of Hypericum roeperianum we isolated a new tricyclic acylphloroglucinol (1), a new tetracyclic acylphloroglucinol (2), and a new prenylated bicyclic acylphloroglucinol (3) together with four known prenylated (4-7) and three known tetracyclic acylphloroglucinol derivatives (8-10). Structure elucidation was based on UV, IR, [α]D(25), 1D- and 2D-NMR experiments. Furthermore, empetrifranzinans A (8) and C (9) were synthesized regioselectively in only two steps. The isolated compounds were evaluated for their cytotoxicity against PC-3 and HT-29 cancer cell lines as well as antibacterial and anthelmintic activities. They were also tested in cell-based assays for cytotoxicity against MT-4 cells and for anti-HIV activity in infected MT-4 cells. Significant anthelmintic activity against Caenorhabditis elegans was exhibited by compound 7 (3-geranyl-1-(2'-methylbutanoyl)-phloroglucinol), which might provide a new lead.


Assuntos
Anti-Helmínticos/química , Antineoplásicos Fitogênicos/química , Antivirais/química , Cromanos/química , Hypericum/química , Floroglucinol/análogos & derivados , Animais , Anti-Helmínticos/síntese química , Anti-Helmínticos/farmacologia , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cromanos/isolamento & purificação , HIV-1/efeitos dos fármacos , Humanos , Hypericum/metabolismo , Espectroscopia de Ressonância Magnética , Conformação Molecular , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Estereoisomerismo , Xantenos/química , Xantenos/isolamento & purificação
14.
J Pharm Biomed Anal ; 115: 383-7, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26275727

RESUMO

Trigonelline (3-carboxy-1-methyl pyridinium) was identified as a relevant bioactivity and taste imparting component in Balanites aegyptiaca fruit, using (1)H NMR of crude extracts without any fractionation or isolation step. The structural integrity of trigonelline was established within the extract matrix via(1)H NMR, (1)H-(1)H COSY, HMQC and HMBC and by comparison with authentic standard. A quantitative (1)H NMR method (qHNMR) was used to determine trigonelline concentrations in the peel and pulp of B. aegyptiaca fruit of 8 and 13mgg(-1), respectively. Trigonelline so far has not been reported from B. aegyptiaca or its genus as it easily escapes LC-MS based detection. Its discovery provides novel insight into the balanite fruits antidiabetic properties as the compound is known for a pronounced hypoglycemic effect. In addition, it is likely to impart the perceptible bitter taste portion to balanites sweet bitter taste. UPLC-MS of the crude extract additionally revealed the fruit flavonoid pattern showing quercetin/isorhamnetin flavonol conjugates in addition to epicatechin, the latter being present at much lower levels.


Assuntos
Alcaloides/análise , Balanites/química , Hipoglicemiantes/análise , Metabolômica/métodos , Extratos Vegetais/análise , Espectroscopia de Prótons por Ressonância Magnética , Cromatografia Líquida , Frutas , Espectrometria de Massas , Metabolômica/normas , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética/normas , Padrões de Referência , Paladar
15.
Chem Biodivers ; 12(6): 955-62, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26080741

RESUMO

Bacterial wilts of potato, tomato, pepper, and or eggplant caused by Ralstonia solanacearum are among the most serious plant diseases worldwide. In this study, the issue of developing bactericidal agents from natural sources against R. solanacearum derived from plant extracts was addressed. Extracts prepared from 25 plant species with antiseptic relevance in Egyptian folk medicine were screened for their antimicrobial properties against the potato pathogen R. solancearum by using the disc-zone inhibition assay and microtitre plate dilution method. Plants exhibiting notable antimicrobial activities against the tested pathogen include extracts from Acacia arabica and Punica granatum. Bioactivity-guided fractionation of A. arabica and P. granatum resulted in the isolation of bioactive compounds 3,5-dihydroxy-4-methoxybenzoic acid and gallic acid, in addition to epicatechin. All isolates displayed significant antimicrobial activities against R. solanacearum (MIC values 0.5-9 mg/ml), with 3,5-dihydroxy-4-methoxybenzoic acid being the most effective one with a MIC value of 0.47 mg/ml. We further performed a structure-activity relationship (SAR) study for the inhibition of R. solanacearum growth by ten natural, structurally related benzoic acids.


Assuntos
Acacia/química , Antibacterianos/farmacologia , Ácido Gálico/farmacologia , Lythraceae/química , Extratos Vegetais/farmacologia , Ralstonia solanacearum/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Frutas/química , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ralstonia solanacearum/crescimento & desenvolvimento , Relação Estrutura-Atividade
16.
Nat Prod Commun ; 9(5): 659-60, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25026714

RESUMO

Two new fungal pigments named schweinitzins A and B (1-2), together with (S)-torosachrysone-8-O-methyl ether (3) and emodin-6,8-di-O-methyl ether (4) have been isolated from the methanolic extract of the fruit bodies of Xylaria schweinitzii (Xylariaceae) collected in Cuc Phuong national park, Ninh Binh province, Vietnam, by silica gel column chromatography and preparative HPLC. Their structures were elucidated by spectroscopic analysis such as IR, UV-Vis, 2D NMR and FT-ICR-MS. In addition, two compounds (1 and 3) showed strong cytotoxicity against all four cancer cell lines, KB (a human epidermal carcinoma), MCF7 (human breast carcinoma), SK-LU-I (human lung carcinoma) and HepG2 (hepatocellular carcinoma).


Assuntos
Antracenos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Naftalenos/isolamento & purificação , Xylariales/química , Antracenos/química , Antracenos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Espectroscopia de Ressonância Magnética , Naftalenos/química , Naftalenos/farmacologia , Vietnã
17.
Nat Prod Commun ; 7(2): 257-60, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22474974

RESUMO

The chemical composition of the essential oil obtained from the leaves of Pulicaria undulata Gamal Ed Din (syn P. orientalis sensu Schwartz and P. jaubertii Gamal Ed Din) was analyzed by GC-MS. Major compounds of P. undulata oil were the oxygenated monoterpenenes, carvotanacetone (91.4%) and 2,5-dimethoxy-p-cymene (2.6.%). The antimicrobial activity of the essential oil was evaluated against six microorganisms, Escherichia coli Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Candida albicans, using disc diffusion and broth microdilution methods. The oil showed the strongest bactericidal activity against Staphylococcus aureus and methicillin-resistant S. aureus, as well as Candida albicans. The essential oil showed moderate cytotoxic activity against MCF-7 breast tumor cells, with an IC50 of 64.6 +/- 13.7 microg/mL. Bioautographic assays were used to evaluate the acetylcholinesterase inhibitory effect as well as antifungal activity of the oil against Cladosporium cucumerinum.


Assuntos
Antibacterianos/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Pulicaria/química , Antibacterianos/química , Bactérias/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Folhas de Planta/química , Óleos de Plantas/química , Iêmen
18.
Phytochemistry ; 76: 60-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22336263

RESUMO

Glycyrrhiza glabra, commonly known as licorice, is a popular herbal supplement used for the treatment of chronic inflammatory conditions and possesses anticancer and antiviral activities. This species contains a plethora of phytochemicals including terpenoids, saponins, flavonoids, polyamines and polysaccharides. The full complement of bioactive compounds has yet to be elucidated, a step necessary in order to explain its medicinal use. There are over 30 species in the Glycyrrhiza genus world-wide, most of which have been little characterized in terms of phytochemical or pharmacological properties. Here, large scale multi-targeted metabolic profiling and fingerprinting techniques were utilized to help gain a broader insight into Glycyrrhiza species chemical composition. UV, MS and NMR spectra of extracted components were connected with NMR, MS, and multivariate analyses data from Glycyrrhiza glabra, Glycyrrhiza uralensis, Glycyrrhiza inflata and Glycyrrhiza echinata. Major peaks in (1)H NMR and MS spectra contributing to the discrimination among species were assigned as those of glycyrrhizin, 4-hydroxyphenyl acetic acid, and glycosidic conjugates of liquiritigenin/isoliquiritigenin. Primary metabolites profiling using GC-MS revealed the presence of cadaverine, an amino acid, exclusively found in G. inflata roots. Both LC-MS and NMR were found effective techniques in sample classification based on genetic and or geographical origin as revealed from derived PCA analysis.


Assuntos
Glycyrrhiza/metabolismo , Metaboloma , Mapeamento de Peptídeos/métodos , Raízes de Plantas/metabolismo , Cadaverina/metabolismo , Cromatografia Líquida/métodos , Flavanonas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Glycyrrhiza/classificação , Ácido Glicirrízico/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Fenilacetatos/metabolismo , Análise de Componente Principal , Especificidade da Espécie , Sacarose/metabolismo
19.
Nat Prod Commun ; 5(6): 869-72, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20614812

RESUMO

A new isoquinoline alkaloid, ampullosine (3-methyl-isoquinoline-6-carboxylic acid, 1), was isolated from Sepedonium ampullosporum and characterized by spectroscopic analysis and chemical reactions. This compound is responsible for the deep yellow color of the culture fluid of this species. Moreover, the known compounds sepedonin (2) and anhydrosepedonin (3) were detected. Twelve strains belonging to eight species of Sepedonium have been screened for these three metabolites by LC/ESI-SRM (selected reaction monitoring). Ampullosine (1) could be detected in almost all species in Sepedonium, but not in the phylogenetically more distant species S. brunneum and S. tulasneanum. Anhydrosepedonin (3) showed antifungal activity against the phytopathogenic fungus Cladosporium cucumerinum.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Ascomicetos/química , Isoquinolinas/química , Isoquinolinas/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Estrutura Molecular
20.
Planta Med ; 76(1): 47-52, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19639538

RESUMO

The present paper describes the phytochemical and anti-staphylococcal activity investigation of the dichloromethane extract of the Brazilian plant Zizyphus joazeiro Mart. The purification steps were guided by bioassays against 17 bacterial strains of clinical sources, including methicillin-resistant (MRSA) and -sensitive (MSSA) Staphylococcus aureus as well as MRSA (ATCC 33591) and MSSA (ATCC 29213) reference strains. One of the more active fractions is comprised of three lupane-type triterpenes, the methylbetulinate (1) as well as the known betulinic (2) and alphitolic (3) acids and, for the first time in the Z. joazeiro, two ceanothane type triterpenes, the methylceanothate (4) and the epigouanic acid A (5). These substances were assayed against one clinical (PVL+) and the reference strains of S. aureus as well as the ATTC 12228 strain of S. epidermidis, in concentrations that varied from 128 to 0.125 microg/mL in order to establish the minimum inhibitory concentration (MIC) of the drugs. The minimum bactericide concentration (MBC) was also evaluated to distinguish the bactericidal from bacteriostatic activity of the crude fractions and single compounds. Compounds 3 and 4 possess the highest antibacterial activity. They inhibit all bacteria tested at 32 microg/mL and 16 microg/mL, respectively, while the other compounds showed no activity at 128 microg/mL. In contrast to single compounds, the triterpenoid fraction showed bactericidal activity at 256 microg/mL. Structural elucidations are based on 1D and 2D NMR spectroscopy as well as HR-FT-ICR-MS experiments.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Ziziphus/química , Bactérias/efeitos dos fármacos , Brasil , Medicina Tradicional , Testes de Sensibilidade Microbiana , Triterpenos/isolamento & purificação
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