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1.
An Acad Bras Cienc ; 93(4): e20200443, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495202

RESUMO

Phytochemical studies of Cespedesia spathulata (Ochnaceae) leaves using 1H, 13C NMR, and GC-MS have led to the isolation of some metabolites identified for the first time in these species such as cathechin, epicatechin, vitexin, orientin, 6''-O-acetyl-vitexin, sitosterol, stigmasterol, phytol, 4,5-dihydrovomifoliol and a mixture of aliphatic methyl esters, together with ochnaflavone, which was previously isolated from this plant. The modulating activity of some fractions and compounds from Cespedesia spathulata towards tyrosinase enzyme was assayed by spectroscopic and theoretical means/experiments. The dichloromethane fraction (133 µg mL-1) and ochnaflavone (333 µM) inhibited tyrosinase activity by 20 % and 2.0 %, respectively, whereas the ethyl acetate fraction (666 µg mL-1) and ±catechins (catechin and epicatechin - 800 µM) activated it by 104 % and 384 %, respectively. Quantum chemical calculations suggested that catechin and epicatechin are better activators than L-DOPA by interacting with Cu (II) ions. Molecular docking results suggested that hydrogen bonding and hydrophobic interactions are the main binding forces between each tyrosinase activator and the amino acid residues inside the active protein binding pocket.


Assuntos
Ochnaceae , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta
2.
Cells ; 10(3)2021 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804755

RESUMO

Plants have historically been a rich source of successful anticancer drugs and chemotherapeutic agents, with research indicating that this trend will continue. In this contribution, we performed high-throughput cytotoxicity screening of 702 extracts from 95 plant species, representing 40 families of the Brazilian Cerrado biome. Activity was investigated against the following cancer cell lines: colon (Colo205 and Km12), renal (A498 and U031), liver (HEP3B and SKHEP), and osteosarcoma (MG63 and MG63.3). Dose-response tests were conducted with 44 of the most active extracts, with 22 demonstrating IC50 values ranging from <1.3 to 20 µg/mL. A molecular networking strategy was formulated using the Global Natural Product Social Molecular Networking (GNPS) platform to visualize, analyze, and annotate the compounds present in 17 extracts active against NCI-60 cell lines. Significant cytotoxic activity was found for Salacia crassifolia, Salacia elliptica, Simarouba versicolor, Diospyros hispida, Schinus terebinthifolia, Casearia sylvestris var. lingua, Magonia pubescens, and Rapanea guianensis. Molecular networking resulted in the annotation of 27 compounds. This strategy provided an initial overview of a complex and diverse natural product data set, yielded a large amount of chemical information, identified patterns and known compounds, and assisted in defining priorities for further studies.


Assuntos
Ecossistema , Ensaios de Triagem em Larga Escala , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Brasil , Linhagem Celular Tumoral , Geografia , Humanos , Concentração Inibidora 50 , Solventes
3.
Molecules ; 25(22)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33218181

RESUMO

The genus Cedrela P. Browne, which belongs to the Meliaceae family, has eighteen species. Trees of this genus are of economic interest due to wood quality, as well as being the focus of studies because of relevant biologic activities as in other Meliaceae species. These activities are mainly related to limonoids, a characteristic class of compounds in this family. Therefore, the aim of this review is to perform a survey of the citations in the literature on the Cedrela genus species. Articles were found on quantitative and qualitative phytochemical studies of the Cedrela species, revealing the chemical compounds identified, such as aliphatics acid and alcohol, flavonoids, tocopherol, monoterpenes, sesquiterpenes, triterpenes, cycloartanes, steroids, and limonoids. Although some activities were tested, the majority of studies focused on the insecticidal, antifeedant, or insect growth inhibitor activities of this genus. Nonetheless, the most promising activities were related to their antimalarial and antitripanocidal effects, although further investigations are still needed.


Assuntos
Cedrela/química , Compostos Fitoquímicos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Cedrela/crescimento & desenvolvimento , Concentração Inibidora 50 , Compostos Fitoquímicos/química , Desenvolvimento Vegetal/efeitos dos fármacos
4.
Parasitology ; 147(13): 1559-1568, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32741411

RESUMO

Medicinal plants have been the focus of several studies due to their nematicide properties which can be used to control nematodes in sheep. No study has examined the morphological effects of Cymbopogon citratus on nematodes. Thus, this study evaluated the chemical composition, nematicidal activity and effects of C. citratus extracts on the morphology of eggs and infective larvae (L3) of sheep. Aqueous and methanolic extracts and fractions of C. citratus were obtained and analysed in vitro. The C. citratus extracts were effective against Haemonchus spp. and Trichostrongylus spp. larvae and eggs. Ten fractions were obtained from C. citratus, six of which had high ovicidal activity at 1000 µg mL-1, and two fractions had high activity at all tested concentrations. The phytochemical analysis identified the presence of compounds such as terpenoids, various ketones, esters, and fatty acids. The ultrastructural analysis showed deformations of the cuticle and wilting along the body of the nematodes at all concentrations. The muscular layer, intestinal cells and the mitochondria profile showed damage compared to the typical pattern. Ultra-thin sections of eggs treated with methanolic fractions of C. citratus presented modifications. This study showed the biological activity and effects of C. citratus on the gastrointestinal nematodes in sheep.


Assuntos
Cymbopogon/química , Hemoncose/veterinária , Haemonchus/efeitos dos fármacos , Extratos Vegetais/farmacologia , Doenças dos Ovinos/tratamento farmacológico , Tricostrongilose/veterinária , Trichostrongylus/efeitos dos fármacos , Animais , Brasil , Hemoncose/tratamento farmacológico , Haemonchus/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Óvulo/efeitos dos fármacos , Óvulo/crescimento & desenvolvimento , Extratos Vegetais/química , Plantas Medicinais/química , Ovinos , Carneiro Doméstico , Tricostrongilose/tratamento farmacológico , Trichostrongylus/crescimento & desenvolvimento
5.
ACS Omega ; 5(23): 13656-13663, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32566830

RESUMO

Six sesquiterpenoids with unprecedented macrocyclic humulene-type structures, namely, dolichocarpols A-E (1-5) with ether-bridged bicyclic rings between C-10 and C-2, C-10 and C-7, C-10 and C-6 (×2), and C-6 and C-3 and dolichocarpol F (6) cyclized between C-7 and C-2 and with an ether bridge between C-10 and C-3, were isolated from Anaxagorea dolichocarpa roots. The structures of the compounds were elucidated by NMR, MS, and IR data. Absolute configurations of compounds 1-3 and 6 were established on the basis of data from electronic circular dichroism, whereas relative configurations of compounds 4 and 5 were suggested by the NOESY spectrum. In addition, a putative biosynthetic pathway of the compounds is proposed. Furthermore, the cytotoxicity of 3, 4, and 6 against HCT-116 (human colorectal carcinoma) and L929 (murine fibroblast) was evaluated.

6.
An Acad Bras Cienc ; 92(1): e20180569, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32321015

RESUMO

The essential oils obtained by hydrodistillation from fresh leaves of Vitex agnus-castus and Ocimum campechianum, and from fresh inflorescences of Ocimum carnosum were analysed by GC-FID and GC-MS. The major components of V. agnus-castus essential oil were identified as 1,8-cineole (47.9%), terpinyl α-acetate (11.6%), sabinene (11.2%) and caryophyllene oxide (9.7%), while in the O. campechianum essential oil were eugenol (72.1%), ß-elemene (6.8%), (E)-caryophyllene (6.4%) and bicyclogermacrene (5.2%). Linalool (79.0%), α-epi-cadinol (5.4%), terpinen-4-ol (3.2%) and 1,8-cineole (2.8%) were the major constituents in the O. carnosum essential oil. The essential oils were subsequently evaluated for their larvicidal and cytotoxic activities. Larval bioassay against Aedes aegypti of V. agnus-castus, O. campechianum and O. carnosum essential oils showed LC50 values of 97.55 ± 0.35, 81.45 ± 0.35 and 109.49 ± 0.35 µg/mL, respectively. The in vitro cytotoxic activities of the essential oils has been evaluated on breast adenocarcinoma (MCF-7), lung carcinoma (NCI-H292), pro-myelocytic leukemia (HL-60), and cervical adenocarcinoma (HEP-2) human cell lines, and pro-myelocytic leukemia cells lines (HL-60) were found to be the most sensitive to all the essential oils tested than the others. This is the first report on larvicidal and cytotoxic activities of these essential oils.


Assuntos
Aedes/efeitos dos fármacos , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Ocimum/química , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacocinética , Vitex/química , Animais , Bioensaio , Linhagem Celular Tumoral/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Inseticidas/isolamento & purificação , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Folhas de Planta/química , Óleos Vegetais/química , Testes de Toxicidade , Vitex/classificação
7.
Microb Pathog ; 143: 104144, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32194182

RESUMO

There has been a rapid increase in the incidence and prevalence of opportunistic bacterial infections. Inappropriate use of current antibiotics has continuously contributed to the emergence of resistance to conventional antibiotic therapy. Therefore, the search for natural molecules that are able to combat infections is of great public interest, and many of these compounds with antimicrobial properties can be obtained from phytochemical studies of medicinal plants. In this context, this study reports the isolation and characterization of the flavonoid, kaempferol 7-O-ß-D-(6″-O-cumaroyl)-glucopyranoside, from Croton piauhiensis leaves. Additionally, the intrinsic antimicrobial action of the compound and its enhancement against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus strains were assessed. The minimum inhibitory concentration (MIC) of the compound was determined using broth microdilution assays. To evaluate the modulatory effect of the flavonoid, the MIC of antibiotics amikacin and gentamicin, belonging to the class aminoglycosides was assessed, with and without the compound in sterile microplates. The results of intrinsic antibacterial activity tests revealed that the compound had no antibacterial activity against strains tested at concentrations <1024 µg/mL. The combination of the flavonoid at a concentration of 128 µg/mL with gentamicin presented synergistic effects against S. aureus 10 and E. coli 06, and also reduced the MIC from 16 µg/mL to 4 µg/mL and 8 µg/mL, respectively. Amikacin also showed synergistic effects against S. aureus 10 and E. coli 06. We also observed reduced MIC for both, from 128 µg/mL to 32 µg/mL; however, antagonism for P. aeruginosa increased the MIC from 16 µg/mL to 64 µg/mL. The combination of the flavonoid with the aminoglycosides may be an alternative to potentiate the expected results in treatment against S. aureus and E. coli, since their association leads to a synergistic effect, reducing the MIC of these drugs and decreasing the dose necessary for therapeutic success.


Assuntos
Antibacterianos/farmacologia , Croton/química , Quempferóis/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/isolamento & purificação , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Gentamicinas/administração & dosagem , Gentamicinas/farmacologia , Quempferóis/administração & dosagem , Quempferóis/isolamento & purificação , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Staphylococcus aureus/efeitos dos fármacos
8.
J Nat Prod ; 82(10): 2721-2730, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31599155

RESUMO

This study represents the first phytochemical analysis of Stillingia loranthacea (S. loranthacea) and describes new terpenoids obtained from the root bark of this species. The fractionation of the hexane extract from the root bark led to the isolation of two new 28-nor-taraxarenes derivatives, loranthones A and B (1 and 2), four new tigliane diterpenes (5-8), three known tigliane diterpenes (9-11), and three known flexibilene diterpenes, tonantzitlolones A-C (12-14). The investigation of these compounds and the use of a molecular networking-based prioritization approach afforded two other new 28-nor-taraxarenes, loranthones C and D (3 and 4). The cytotoxicity of compounds 1, 2, and 5-14 was evaluated against Vero cells, and their 20% cytotoxic concentration (CC20) values varied from 8.7 to 328 µM; antiviral activity was tested against an epidemic Zika virus (ZIKV) strain circulating in Brazil. Six out of 12 compounds (2, 5, 9-11, and 14) exhibited significant antiviral effects against ZIKV. Specifically, compounds 2 and 5 offered the most promise as lead compounds as they had a 1.7 and 1.8 log10 TCID50/mL reduction in ZIKV replication, respectively. Together, the present findings have identified S. loranthacea terpenoids as potent anti-ZIKV inhibitors and pave the way to the development of possible new treatments against this devastating pathogen.


Assuntos
Diterpenos/isolamento & purificação , Euphorbiaceae/química , Triterpenos/isolamento & purificação , Replicação Viral/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Animais , Chlorocebus aethiops , Diterpenos/química , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Triterpenos/química , Triterpenos/farmacologia , Células Vero , Zika virus/fisiologia
9.
Chem Biodivers ; 16(12): e1900313, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31545879

RESUMO

Cissampelos sympodialis Eichler is well studied and investigated for its antiasthmatic properties, but there are no data in the literature describing antibacterial properties of alkaloids isolated from this botanical species. This work reports the isolation and characterization of phanostenine obtained from roots of C. sympodialis and describes for the first time its antimicrobial and antibiotic modulatory properties. Phanostenine was first isolated from Cissampelos sympodialis and its antibacterial activities were determined. Chemical structures of the alkaloid isolate were determined using spectroscopic and chemical analyses. Phanostenine was also tested for its antibacterial activity against standard strains and clinical isolates of Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentration (MIC) was determined in a microdilution assay and for the evaluation of antibiotic resistance-modifying activity. MIC of the antibiotics was determined in the presence or absence of phanostenine at sub-inhibitory concentrations. The evaluation of antibacterial activity by microdilution assay showed activity for all strains with better values against S. aureus ATCC 12692 and E. coli 27 (787.69 mm). The evaluation of aminoglycoside antibiotic resistance-modifying activity showed reduction in the MIC of the aminoglycosides (amikacin, gentamicin and neomycin) when associated with phanostenine, MIC reduction of antibiotics ranging from 21 % to 80 %. The data demonstrated that phanostenine possesses a relevant ability to modify the antibiotic activity in vitro. We can suggest that phanostenine presents itself as a promising tool as an adjuvant for novel antibiotics formulations against bacterial resistance.


Assuntos
Alcaloides/química , Antibacterianos/química , Derivados de Benzeno/química , Cissampelos/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Derivados de Benzeno/isolamento & purificação , Derivados de Benzeno/farmacologia , Cissampelos/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Compostos de Anéis Fundidos , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Staphylococcus aureus/efeitos dos fármacos
10.
Molecules ; 24(14)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295814

RESUMO

Zornia brasiliensis Vogel (Leguminosae) is a species popularly known in Brazil as "urinária", "urinana", and "carrapicho", it is popularly used as a diuretic and in the treatment of venereal diseases. A specific methodology to obtain a saponin-enriched fraction and high-performance liquid chromatography coupled with diode array detection, ion trap mass spectrometry, and TOF-MS (HPLC-DAD-ESI-MS/MS) was applied for the analysis of triterpene saponins. The MS and MS/MS experiments were carried out by ionization in negative mode. Molecular mass and fragmentation data were used to support the structural characterization of the saponins. Based on retention times, high-resolution mass determination and fragmentation, 35 oleanane-triterpene saponins were tentatively identified in Z. brasiliensis.


Assuntos
Cromatografia Líquida de Alta Pressão , Fabaceae/química , Extratos Vegetais/análise , Saponinas/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Triterpenos/análise , Espectroscopia de Ressonância Magnética , Redes e Vias Metabólicas , Estrutura Molecular , Extratos Vegetais/química , Saponinas/química , Triterpenos/química
11.
An Acad Bras Cienc ; 91(2): e20180204, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038534

RESUMO

This study evaluated the antibacterial, antifungal, and antioxidant effect of 7-hydroxy-4',6-dimethoxy-isoflavone and essential oil of Myroxylon peruiferum. The compound was isolated and its structure elucidated by NMR. The chemical composition of essential oil determined by GC-MS analysis. To evaluation of antimicrobial activity, the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC) were performed. In addition to analysis of antioxidant activity, DPPH radical scavenging tests, iron chelating assay (FIC), antioxidant reducing power assay (FRAP) and ß-carotene bleaching assay (BCB) were performed. For the essential oil were identified 24 organized compounds having as main constituents; Germacrene D (17.2%), α-pinene (14.8%) and E-caryophyllene (10.8%). The results showed that isoflavone (2000 to 156 µg/mL) and essential oil (5.0 to 1.25%) present antibacterial and antifungal activity against Gram-positive bacteria and filamentous fungi. The isoflavone and the essential oil also presented antioxidant activity in all the tests, mainly on inhibition of the oxidation of ß-carotene test concentrations ranging from 60 to 100%. In conclusion, isoflavone and essential oil from M. peruiferum present an antimicrobial alternative against Gram-positive bacteria, especially of the genus Staphylococcus and dermatophyte fungi of the genus Trichophyton, as well as a natural compound antioxidant.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Myroxylon/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/análise , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Quelantes de Ferro , Isoflavonas/análise , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Extratos Vegetais/química , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Tempo
12.
Molecules ; 24(6)2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30875889

RESUMO

A phytochemical study of leaves and twigs of Psychotria nuda resulted in 19 compounds, including five indole alkaloids, N,N,N-trimethyltryptamine, lyaloside, strictosamide, strictosidine, and 5α-carboxystrictosidine; two flavonolignans, cinchonain Ia and cinchonain Ib; an iridoid, roseoside; a sugar, lawsofructose; a coumarin, scopoletin; a diterpene, phytol; three triterpenes, pomolic acid, spinosic acid, and rotungenic acid; and five steroids, sitosterol, stigmasterol, campesterol, ß-sitosterol-3-O-ß-d-glucoside, and ß-stigmasterol-3-O-ß-d-glucoside. Some compounds were evaluated for their in vitro activity against Mycobacterium tuberculosis and their ability to inhibit NO production by macrophages stimulated by lipopolysaccharide (LPS). The compounds pomolic acid, spinosic acid, strictosidine, and 5α-carboxystrictosidine displayed antimycobacterial activity with minimum inhibitory concentrations ranging from 7.1 to 19.2 µg/mL. These compounds showed promising inhibitory activity against NO production (IC50 3.22 to 25.5 µg/mL). 5α-carboxystrictosidine did not show cytotoxicity against macrophages RAW264.7 up to a concentration of 100 µg/mL. With the exception of strictosamide, this is the first report of the occurrence of these substances in P. nuda.


Assuntos
Alcaloides/análise , Antibacterianos/análise , Antioxidantes/análise , Psychotria/química , Triterpenos/análise , Alcaloides/farmacologia , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Lipopolissacarídeos/efeitos adversos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Óxido Nítrico/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Células RAW 264.7 , Triterpenos/farmacologia
13.
Bioorg Chem ; 86: 665-673, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30826627

RESUMO

The new alkene lactone, (3E)-5,6-dihydro-5-(hydroxymethyl)-3-docdecylidenefuran-3(4H)-one (1), named majoranolide B, and three alkene lactones known as majorenolide (2), majoranolide (3) and majorynolide (4) were obtained from the aerial parts of Persea fulva (Lauraceae). The structures were elucidated in light of extensive spectroscopic analysis, including 1D, 2D NMR (1H, 13C, 1H-1H-COSY, HMBC and HSQC) and HR-ESI-MS. These compounds were screened for their in vitro antiproliferative activity in rat C6 glioma and astrocyte cells using MTT assay and in silico by molecular docking against targets that play a central role in controlling glioma cell cycle progression. Majoranolide (3) is the most active compound with IC50 6.69 µM against C6 glioma cells, followed by the compounds 1 (IC50 9.06 µM), 2 (IC50 12.04 µM) and 4 (IC50 41.90 µM). The alkene lactones 1-3 exhibited lower toxicity in non-tumor cells when compared to glioma cells. Molecular docking results showed that majoranolide establishes hydrogen bonds with all targets through its α,ß-unsaturated-γ-lactone moiety, whereas the long-chain alkyl group binds by means of several hydrophobic bonds. In the present study, it can be concluded from the anti-proliferative activity of isolates against C6 glioma cells that lactone constituents from P. fulva could have a great potential for the control of C6 glioma cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Lactonas/farmacologia , Lauraceae/química , Simulação de Acoplamento Molecular , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Lactonas/química , Lactonas/isolamento & purificação , Estrutura Molecular , Folhas de Planta/química , Ratos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
Microb Drug Resist ; 25(3): 434-438, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30741597

RESUMO

INTRODUCTION: Staphylococcus aureus represents the most common etiologic agent of purulent infections, affecting humans and animals. Escherichia coli is one of the principal causes of infectious diseases, mainly diarrheal diseases due to enterotoxin action. There are many reports indicating that these bacteria are multidrug-resistant (MDR) pathogens. OBJECTIVE: In this study, we investigated the antimicrobial and modulatory activities of 5-hydroxy-3,7,4'-trimethoxyflavone (VG.EF.CLII) against E. coli and S. aureus strains. METHODS: 5-Hydroxy-3,7,4'-trimethoxyflavone was isolated from Vitex gardneriana Schauer leaves and structurally characterized using nuclear magnetic resonance. The antibacterial effect of VG.EF.CLII and modulation of antibiotic activity, both determined by minimum inhibitory concentration, were assessed using microtiter plates. RESULTS: VG.EF.CLII showed bacterial growth inhibition at concentrations ≤512 µg/mL, and synergistic effects were observed for the modulation of two distinct antibiotic classes (the fluoroquinolone norfloxacin and the aminoglycoside gentamicin). CONCLUSION: 5-Hydroxy-3,7,4'-trimethoxyflavone isolated from V. gardneriana showed promising antimicrobial activity against MDR bacterial strains S. aureus 358 and E. coli 27 when associated with the antibiotics norfloxacin and gentamicin. Therefore, this natural product can contribute to the control of bacterial resistance.


Assuntos
Antibacterianos/química , Flavonoides/química , Extratos Vegetais/química , Folhas de Planta/química , Vitex/química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Flavonoides/farmacologia , Testes de Sensibilidade Microbiana/métodos , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos
15.
Rev. bras. farmacogn ; 29(1): 40-45, Jan.-Feb. 2019. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-990765

RESUMO

Abstract The chemical study of roots from Azadirachta indica A. Juss., Meliaceae, led to the isolation of two new terpenoids, limonoid morenolide and diterpene 17-hydroxy-sandaracopimar-8,15-dien-11-one, in addition to the four well-known limonoids nimbinene, nimbinal, nimbandiol and salannin, and three diterpenoids nimbidiol, ferruginol, and 6,7-dehydroferruginol. Their structural elucidations were based on one and bidimensional Nuclear Magnetic Resonance and Electrospray ionization mass spectrometry spectra data which was compared to the data found in literature. The anti-inflammatory, cytotoxic and antimycobacterial activities of the identified terpenoids were evaluated.

16.
Nat Prod Res ; 33(12): 1769-1772, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29390916

RESUMO

Astrocytic tumour cells derived from human (GL-15) and rat (C6) gliomas, as well as non-tumoural astrocytic cells, were exposed to the saponin-rich fraction (SF) from Agave sisalana waste and the cytotoxic effects were evaluated. Cytotoxicity assays revealed a reduction of cell viability that was more intensive in glioma than in non-tumoural cells. The SF induced morphological changes in C6 cells. They were characterised by cytoplasmic vacuole formation associated with increase in the formation of acidic lysosomes. The SF was subjected to purification on Sephadex LH-20, which characterised three probable steroidal saponins (sisalins) by electrospray ionisation mass spectrometry multistage (ESI-MSn). Sisalins from sisal may be responsible for the cytotoxicity, which involves cytoplasmatic vacuole formation and selective action for glioma cells.


Assuntos
Agave/química , Antineoplásicos Fitogênicos/farmacologia , Astrócitos/efeitos dos fármacos , Saponinas/química , Saponinas/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Astrócitos/patologia , Linhagem Celular Tumoral , Chlorocebus aethiops , Citoplasma/efeitos dos fármacos , Citoplasma/patologia , Glioma/patologia , Humanos , Estrutura Molecular , Extratos Vegetais/química , Ratos , Saponinas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem , Vacúolos/efeitos dos fármacos , Vacúolos/patologia , Células Vero
17.
Artigo em Inglês | MEDLINE | ID: mdl-30524481

RESUMO

Ouratea fieldingiana (Gardner) Engl is popularly used for wound healing. This study describes the main chemical compounds present in extracts of O. fieldingiana and evaluates their biological potential by investigating antifungal, antioxidant, and anticholinesterase activities. The action mechanism of main antifungal compound was investigated by molecular docking using the enzyme sterol 14-α demethylase, CYP51, required for ergosterol biosynthesis. The seeds and leaves were extracted with ethanol in a Soxhlet apparatus and by maceration, respectively. Both extracts were subjected to silica gel column chromatography for isolation of main constituents, followed by purification in sephadex. The structures of compounds were established by 1H and 13C-NMR spectroscopy and identified by comparison with literature data as amentoflavone and kaempferol 3-O-rutinoside, respectively. The antioxidant activities of the extracts were determined by the DPPH and ABTS free radical inhibition methods. In general, the extracts with the highest antioxidant activity corresponded to those with higher content of phenolic compounds and flavonoids. The ethanol extracts and two isolated compounds presented relevant antifungal activity against several Candida strains. The in silico findings revealed that the compound amentoflavone coupled with the CYP450 protein due to the low energy stabilization (-9.39 kcal/mol), indicating a possible mechanism of action by inhibition of the ergosterol biosynthesis of Candida fungi.

18.
Molecules ; 23(6)2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925807

RESUMO

The new pentacyclic triterpene 11ß-hydroxypristimerin (1), along with the known metabolites pristimerin (2), 6-oxopristimerol (3) and vitideasin (4), were isolated from a Salacia crassifolia root wood extract, following a bioassay-guided fractionation approach. Both the extract and the purified triterpenes displayed pronounced cytotoxic activity against human cancer cell lines. The NCI-60 cell line screen revealed that compound 2 was the most active, with a mean GI50 of 0.17 µM, while compound 1 had a mean GI50 of 8.7 µM. A COMPARE analysis of the screening results showed that pristimerin is likely to be the main compound responsible for the cytotoxic activity of the extract (mean GI50 of 0.3 µg·mL−1). A targeted search for pristimerin and related derivatives using LC-MS/MS revealed the presence of pristimerin (2) and 6-oxopristimerol (3) in all Celastraceae species examined and in all plant parts tested, while vitideasin (4) was only detected in the genus Salacia.


Assuntos
Celastraceae/metabolismo , Metabolômica/métodos , Extratos Vegetais/química , Salacia/química , Triterpenos/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Raízes de Plantas/química , Relação Estrutura-Atividade , Triterpenos/isolamento & purificação , Triterpenos/metabolismo , Triterpenos/uso terapêutico
19.
Rev. bras. farmacogn ; 28(3): 333-338, May-June 2018. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-958864

RESUMO

ABSTRACT The organic extracts from stems, roots and leaves of Tephrosia egregia Sandwith, Fabaceae, provided a new flavone, 5-hydroxy-8-(1",2"-epoxy-3"-hydroxy-3"-methylbutyl)-7-methoxyflavone (1), in addition to eleven known compounds: pongaflavone (2), praecansone B (3), 12a-hydroxyrotenone (4), praecansone A, 2',6'-dimethoxy-4',5'-(2",2"-dimethyl)-pyranochalcone, pongachalcone, maackiain, β-sistosterol and its glucoside, p-cumaric acid and cinnamic acid. The structures of all compounds were established on the basis of spectroscopic methods, mainly 1D and 2D NMR and HRESIMS, involving comparison with literature data. Cytotoxicity of compounds 1-4 was evaluated against AGP-01 (cancerous ascitic fluid), HCT-116 (colon adenocarcinoma), HL-60 (leukemia), PC-3 (prostate carcinoma), SF-295 (glioblastoma) and SKMEL 28 (melanoma) cell lines.

20.
Rev. bras. farmacogn ; 28(3): 298-302, May-June 2018. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-958875

RESUMO

ABSTRACT Harrisia adscendens (Gürke) Britton & Rose is a species of the family Cactaceae found in the northeastern semi-arid and popularly known as foxtail. In folk medicine, the roots of this species are used for the treatment of toothache and heartburn. The objective of this study was to perform the isolation and identification of the secondary metabolites obtained from the vegetal drug by chromatographic and spectroscopic techniques and to evaluate the antimicrobial activity of the extract. The qualitative phytochemical analysis of the extract showed suggestive results for the presence of alkaloids. Two compounds were isolated and identified: 2-methyl-9H-β-carboline-2-ion, a β-carboline alkaloid obtained for the first time as a natural product and 2',6'-dihydroxy-4'-methoxyacetophenone-2'-O-β-glucoside. In the antimicrobial tests, it was possible to observe activity against Pseudomonas aeruginosa. The results obtained by spectroscopic techniques allowed to characterize the phytochemical properties of the vegetal drug and may be useful in future studies for production of herbal medicines.

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