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1.
Braz. J. Pharm. Sci. (Online) ; 59: e21508, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1439512

RESUMO

Abstract Ellagic acid (EA) is a phenolic biomolecule. For its biosynthesis, a source of ellagitannins is required, such as strawberries and yeasts, as precursors of the tannase and ß-glucosidase enzymes responsible for hydrolysis of ellagitannins. Two experimental mixture designs were applied., varying the yeast concentration and the number of ellagitannins in the culture medium, evaluating the enzymatic activity and ellagic acid biosynthesis. Aiming to find the optimal compositions of the non-conventional yeasts assessed in the research to biosynthesize ellagic acid feasibly and efficiently using a response surface performing the statistical analysis in the StatGraphics® program for obtaining a higher yield and optimizing the ellagic acid synthesis process, the results indicate that the strains Candida parapsilosis ITM LB33 and Debaryomyces hansenii ISA 1510 have a positive effect on the synthesis of ellagic acid, since as its concentration increases in the mixture the concentration of ellagic acid in the medium also increases; on the other hand, the addition of Candida utilis ITM LB02 causes a negative effect, resulting in the compositions of 0.516876, 0.483124 and 2.58687E-9 respectively, for a treatment under the same conditions, an optimal value of ellagic acid production would be obtained. With an approximate value of 7.33036 mg/mL


Assuntos
Leveduras/classificação , Reatores Biológicos/classificação , Ácido Elágico/síntese química , Otimização de Processos , Debaryomyces/classificação , Candida parapsilosis/classificação
2.
Bioorg Med Chem Lett ; 34: 127758, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33359608

RESUMO

The ATP-adenosine pathway has been recently identified as an attractive immune-oncology target and several drug candidates have been entered clinic trials. Inspired by the report of the first small-molecule CD73inhibitor AB680, we describe the discovery of natural product ellagic acid as a dual CD73 and CD39 inhibitor with an IC50 value of 1.85 ± 0.21 µM and 0.50 ± 0.22 µM, respectively. The result of cytotoxicity assays indicated that ellagic acid is a valuable lead compound with low cytotoxicity effect for immune therapy.


Assuntos
5'-Nucleotidase/antagonistas & inibidores , Antineoplásicos/farmacologia , Apirase/antagonistas & inibidores , Produtos Biológicos/farmacologia , Descoberta de Drogas , Ácido Elágico/farmacologia , Inibidores Enzimáticos/farmacologia , 5'-Nucleotidase/genética , 5'-Nucleotidase/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Apirase/genética , Apirase/metabolismo , Produtos Biológicos/síntese química , Produtos Biológicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Elágico/síntese química , Ácido Elágico/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
3.
Chemistry ; 26(44): 9923-9928, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32084298

RESUMO

Ellagic acid derivatives possess antimicrobial and antibiofilm properties across a wide-range of microbial pathogens. Due to their poor solubility and ambident reactivity it is challenging to synthesize, purify, and characterize the activity of ellagic acid glycosides. In this study, we have synthesized three ellagic acid glycoconjugates and evaluated their antimicrobial and antibiofilm activity in Streptococcus agalactiae (Group B Streptococcus, GBS). Their significant impacts on biofilm formation were examined via SEM to reveal early-stage inhibition of cellular adhesion. Additionally, the synthetic glycosides were evaluated against five of the six ESKAPE pathogens and two fungal pathogens. These studies reveal that the ellagic acid glycosides possess inhibitory effects on the growth of gram-negative pathogens.


Assuntos
Antibacterianos , Biofilmes/efeitos dos fármacos , Ácido Elágico/síntese química , Ácido Elágico/farmacologia , Glicosídeos/síntese química , Glicosídeos/farmacologia , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/ultraestrutura , Antibacterianos/síntese química , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Streptococcus agalactiae/crescimento & desenvolvimento
4.
Metab Brain Dis ; 35(2): 385-399, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31728888

RESUMO

The present study evaluated the neuroprotective and antiepileptic efficacy of ellagic acid (EA) encapsulated in calcium-alginate nanoparticles (Ca2+-ALG NPs) in pentylenetetrazol (PTZ)-induced seizures in male mice. EA was encapsulated in ALG NPs using a nanospray drying method followed by ionotropic crosslinking with Ca2+. Characterization of the developed Ca2+-crosslinked EA-ALG NPs showed spherical, high stability NPs; successful loading of EA within crosslinked ALG NPs; and sustained release of EA. Male Swiss albino mice were divided into ten groups as follows; Group I- (control), Group II (50 mg EA /kg) - (EA), Group III polyethylene glycol (PEG), Group IV EA NPs (50 mg/kg) - (EA NP), Group (50 mg/kg alginate) V void V NPs - (void NPs), Group VI: (37.5 PTZ mg/kg) -(PTZ), Group VII: PTZ and EA - (PTZ-EA). Group VIII: animals received PTZ and PEG concurrently (PTZ-PEG). Group IX; animals received PTZ and void NPs concurrently - (PTZ-void). Group X: animals received PTZ and EA NPs concurrently (PTZ-EA NPs). PTZ was used to induce experimental epilepsy. Ca2+-ALG NPs prevented seizures throughout the experimental period and had a more prominent effect than free EA did. Ca2+-ALG NPs prevented increased glutamate, decreased GABA concentrations and ameliorated increased amyloid-ß and homocysteine levels in the serum and brain. Ca2+-EA-ALG NPs were superior to free EA in improving increased IL-6 and TNF-α. Ca2+-ALG NPs ameliorated PTZ-induced oxidative stress, as evidenced by decreased 4HNE levels and enhanced GSH, GR and GPx levels in the brain. These changes were accompanied by amelioration of apoptosis and its regulating proteins, including Cytochrome C, P53, Bax, Bcl2 and caspase-3 and caspase-9, and protected against DNA damage. Histological examination of the hippocampus confirmed that the neuroprotective effect of Ca2+-EA-ALG NPs was superior and more effective than that of free EA.


Assuntos
Encéfalo/efeitos dos fármacos , Citocinas/antagonistas & inibidores , Ácido Elágico/administração & dosagem , Nanopartículas/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Convulsões/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Encéfalo/metabolismo , Citocinas/metabolismo , Ácido Elágico/síntese química , Masculino , Camundongos , Nanopartículas/química , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/síntese química , Estresse Oxidativo/fisiologia , Pentilenotetrazol/toxicidade , Distribuição Aleatória , Convulsões/induzido quimicamente , Convulsões/metabolismo
5.
Anticancer Agents Med Chem ; 19(12): 1481-1490, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31132979

RESUMO

BACKGROUND: Chemotherapeutic drugs have high toxicity associated with undesirable side-effects. Now, natural products are the most important anti-cancer agents because of their low toxicity and potential effectiveness. METHODS: The half maximal inhibitory concentration (IC50) of amygdalin, naringenin and ellagic acid against breast, colon, and liver cell lines was estimated. The antimutagenic, free radical-, superoxide radical-, and hydroxyl radical- scavenging activities of these phytochemicals were measured. The expression of p53, bid, bax, bcl2, and caspases 9, 3, and 7 was measured by quantitative real-time polymerase chain reaction (qRT-PCR) in breast and liver cells. In addition, the active Caspase 3 protein was estimated in liver cells. RESULTS: Ellagic acid showed the highest antioxidant and antiproliferative activities. Amygdalin and naringenin with low and moderate antioxidant profiles showed a corresponding low and moderate cytotoxicity against cancer cell lines, respectively. Naringenin and ellagic acid had a significant antimutagenic activity which was detected by the Salmonella test. Ellagic acid offered a much better antimutagenic activity than naringenin. The apoptotic pathway evoked by ellagic acid in HepG2 and MCF-7 cells was investigated. The results showed that a caspase-dependent and a caspase-independent apoptosis occurred in MCF-7 and HepG2, respectively. CONCLUSION: The antimutagenic/antioxidant properties are well correlated with the antiproliferative activity of the phytochemicals investigated. This study proved that some easy, quick and cheap assays could predict the antiproliferative activity of many nutraceuticals. Finally, this platform could help in the discovery of new anticancer agents where hundreds of compounds are investigated in the pipeline of drug discovery.


Assuntos
Amigdalina/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Ácido Elágico/farmacologia , Flavanonas/farmacologia , Compostos Fitoquímicos/farmacologia , Amigdalina/síntese química , Amigdalina/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antioxidantes/síntese química , Antioxidantes/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Elágico/síntese química , Ácido Elágico/química , Flavanonas/síntese química , Flavanonas/química , Células HCT116 , Células Hep G2 , Humanos , Radical Hidroxila/análise , Radical Hidroxila/metabolismo , Células MCF-7 , Estrutura Molecular , Compostos Fitoquímicos/síntese química , Compostos Fitoquímicos/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
6.
Chem Pharm Bull (Tokyo) ; 65(11): 1078-1080, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29093294

RESUMO

An ellagic acid-related natural product, nigricanin (1), was synthesized via the Ullmann coupling reaction of 2-bromo-3,4-dialkoxybenzaldehyde (4) followed by the Cannizzaro reaction for desymmetrization of the symmetric biaryl compound (5). Compared to our previously reported study, the presented synthesis improved the sequence step number.


Assuntos
Produtos Biológicos/síntese química , Ácido Elágico/análogos & derivados , Produtos Biológicos/química , Ácido Elágico/síntese química , Ácido Elágico/química , Estrutura Molecular
7.
Nat Prod Res ; 28(19): 1637-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24911045

RESUMO

The infructescence of Platycarya strobilacea Sieb. et Zucc is a well-known traditional medicine in China, Japan and Korea. The infructescence of P. strobilacea Sieb. et Zucc is a rich source of ellagitannins that are composed of ellagic acid (EA) and gallic acid, linked to a sugar moiety. The aim of this study was to prepare EA by acid hydrolysis of crude tannins from the infructescence of P. strobilacea Sieb. et Zucc, and establish a new technological processing method for EA. The natural antioxidant EA was prepared by using the water extraction of infructescence of P. strobilacea Sieb. et Zucc, evaporation, condensation, acid hydrolysis and prepared by the process of crystallisation. The yield percentage of EA from crude EA was more than 20% and the purity of the product was more than 98%, as identified by using HPLC. The structure was identified on the basis of spectroscopic analysis and comparison with authentic compound.


Assuntos
Medicamentos de Ervas Chinesas/química , Ácido Elágico/química , Taninos Hidrolisáveis/isolamento & purificação , Juglandaceae/química , Taninos/química , Cromatografia Líquida de Alta Pressão , Ácido Elágico/síntese química , Ácido Gálico/química , Hidrólise , Taninos Hidrolisáveis/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
8.
Biosci Biotechnol Biochem ; 77(4): 810-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23563555

RESUMO

Okicamelliaside, a glucoside of ellagic acid with potent anti-degranulation activity, was synthesized from ellagic acid. The regioselectivity, solubility, and high reactivity of the intermediates throughout the synthesis were obtained by the complementary use of triisopropylsilyl (TIPS) and methoxyethoxymethyl (MEM) protective groups on the aglycone skeleton.


Assuntos
Degranulação Celular/efeitos dos fármacos , Ácido Elágico/análogos & derivados , Glucosídeos/síntese química , Glucosídeos/farmacologia , Técnicas de Química Sintética , Ácido Elágico/síntese química , Ácido Elágico/química , Ácido Elágico/farmacologia , Glucosídeos/química , Interações Hidrofóbicas e Hidrofílicas
9.
São Paulo; s.n; 25 nov. 2008. 115[8] p. tab, graf.
Tese em Português | LILACS | ID: lil-508071

RESUMO

O morango representa boa fonte de vitamina C, flavonóides e derivados de ácido elágico e tem ampla aceitação pela população brasileira. Os objetivos deste trabalho foram: caracterizar diferentes cultivares quanto aos teores de compostos bioativos, otimizar a metodologia para quantificação do conteúdo de ácido elágico total, purificar e caracterizar estruturalmente os elagitaninos, avaliar sua potencial atividade antiproliferativa, anti-diabetes tipo 2 e anti-hipertensão, estudar a biodisponibilidade desses compostos in vivo. Os resultados demonstraram que existem diferenças significativas nos teores de compostos bioativos entre as cultivares. As melhores condições para determinação dos teores de ácido elágico total foram: extração em acetona 80 % e posterior hidrólise com ácido trifluoracético (TFA) 2N a 120ºC por 60 minutos. A precipitação com acetato de itérbio foi o método mais eficiente para a purificação dos elagitaninos. Após administração por gavagem a ratos de um purificado de elagitaninos, nenhum composto foi detectado no plasma e tecidos analisados...


Assuntos
Animais , Ratos , Antioxidantes , Ácido Ascórbico/análise , Ácido Ascórbico/síntese química , Ácido Elágico/análise , Ácido Elágico/síntese química , Compostos Fenólicos/análise , Compostos Fenólicos/métodos , Alimento Funcional , Fragaria/metabolismo , Disponibilidade Biológica , Técnicas de Cultura , Amostras de Alimentos
10.
Bioprocess Biosyst Eng ; 30(4): 281-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17450459

RESUMO

The individual and interactive effects of physicochemical parameters on ellagitannin acyl hydrolase activity and ellagic acid production by Aspergillus oryzae using ellagitannins from acorn fringe of oak as substrate were studied. Ellagitannins concentration, incubation time were identified as important physicochemical parameters influencing the enzyme synthesis and the production accumulation, and the substrate concentration with initial pH was determined to has an interactive effect on the enzyme synthesis, while ellagitannins concentration and initial pH with incubation time were found to have interactions on the production accumulation. Furthermore, the parameters were optimized by quadratic programming. Under optimum condition, the fermentation run lasted 84 h with 4 g L(-1) ellagitannins concentration, yielding 17.7% ellagic acid. However, the maximum enzyme activity was obtained in 96 h with 5 g L(-1) substrate concentration. The research demonstrated a possible way to develop an efficient approach for recovery of higher added-value product (ellagic acid) from forestry byproduct (acorn fringe of oak).


Assuntos
Aspergillus oryzae/metabolismo , Ácido Elágico/síntese química , Hidrolases/química , Taninos Hidrolisáveis/química , Modelos Químicos , Acilação , Simulação por Computador , Ativação Enzimática
11.
Bioorg Med Chem ; 11(7): 1593-6, 2003 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-12628683

RESUMO

A strain of yeast rendered repair deficient by the conditional expression of the RAD52 locus was used to search for natural products capable of damaging DNA. Four ellagic acid derivatives, namely 3,3'-dimethyl-4'-O-beta-D-glucopyranosyl ellagic acid (1), 3,3',4-trimethyl-4'-O-beta-D-glucopyranosyl ellagic acid (2), 3'-methyl-3,4-O,O-methylidene ellagic acid (3) and 3'-methyl-3,4-O,O-methylidene-4'-O-beta-D-glucopyranosyl ellagic acid (4), were identified by this assay as DNA damaging natural principles from several plants, including Alangium javanicum, Anisophyllea apetala, Crypteronia paniculata, Mouririi sp. and Scholtzia parviflora. Although none of the isolated principles mediated frank strand scission of DNA in vitro, all of them potently inhibited the growth of yeast in the absence of expression of RAD52.


Assuntos
Dano ao DNA/efeitos dos fármacos , Ácido Elágico/análogos & derivados , Ácido Elágico/farmacologia , Bioensaio , DNA Super-Helicoidal/efeitos dos fármacos , Ácido Elágico/síntese química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas/química , Saccharomyces cerevisiae/genética , Relação Estrutura-Atividade
12.
Biosci Biotechnol Biochem ; 65(8): 1869-71, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11577731

RESUMO

The aqueous extract of acetone powder, which had been prepared from Cornus capitata 'Mountain Moon' adventitious roots, cultured in MS medium with a high concentration of Cu2+(10 microM), showed strong oxidative activity toward galloylglucoses. A compound formed from galloyglucoses, such as 1,2,3,4,6-penta-O-galloyl-beta-D-glucose and tannic acid, by the reaction with the crude enzyme solution of the adventitious roots was isolated and characterized as ellagic acid by spectrometric analyses.


Assuntos
Cornaceae/química , Ácido Elágico/síntese química , Taninos Hidrolisáveis , Taninos/química , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Ácido Gálico/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Raízes de Plantas/química , Espectrofotometria Ultravioleta
13.
J Med Chem ; 37(1): 195-200, 1994 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-8289196

RESUMO

We have previously shown that some ellagitannins are potent inhibitors of protein kinase C (PKC). On the basis of this finding, several series of hexahydroxybiphenyl derivatives of ellagic acid were synthesized as simple analogs of these ellagitannins and were evaluated for their inhibitory effect against PKC. Compounds 23 and 26 were found to be potent inhibitors of PKC, while hexakis-(benzyloxy)biphenyl derivatives exhibited weak anti-PKC activity.


Assuntos
Compostos de Bifenilo/síntese química , Dibenzoxepinas/síntese química , Ácido Elágico/análogos & derivados , Proteína Quinase C/antagonistas & inibidores , Compostos de Bifenilo/farmacologia , Dibenzoxepinas/farmacologia , Ácido Elágico/síntese química , Ácido Elágico/química , Ácido Elágico/farmacologia , Humanos , Estrutura Molecular , Proteínas Recombinantes/antagonistas & inibidores , Relação Estrutura-Atividade
14.
J Nat Prod ; 55(10): 1402-7, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1453178

RESUMO

Ellagic acid [1] is a gallic acid dimer that occurs in plants, fruits, and nuts, either in its free form, or in a series of ellagitannins, or as a glucoside. It has been shown to inhibit cancer induced by several types of chemical carcinogens including polycyclic aromatic hydrocarbons, N-nitrosamines, aflatoxin, and aromatic amines. It has been extracted from a number of fruits, including strawberries; however, its presence in the extracts was determined only by hplc connected with a diode array detector. In the present report, ellagic acid was isolated as a tetrahexanoyl derivative 2 from Fragaria ananassa and identified by 13C and 1H nmr and ms. The 13C-nmr shifts of the aromatic carbons adjacent to a hexanoyloxy group were assigned using two new synthetic model compounds: 3,3'-dihexanoyloxydiphenic-2,2',6,6'-dilactone [3] and 4,4'-dihexanoyloxydiphenic-2,2',6,6'-dilactone [4]. Two new derivatives of ellagic acid [1],3,3'-di-beta-D-glucopyranosylellagic acid decaacetate [5] and 3,3'-di-n-octyl-4,4'-dihexanoylellagic acid [7], were also synthesized. Both derivatives were less effective as inhibitors of benzo[a]pyrene tumorigenesis in the lungs of strain A/J mice than ellagic acid.


Assuntos
Ácido Elágico/análogos & derivados , Ácido Elágico/síntese química , Extratos Vegetais/química , Animais , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/uso terapêutico , Ácido Elágico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos A , Extratos Vegetais/uso terapêutico
15.
Rev. farm. bioquim ; 10(1/2): 51-7, 1989.
Artigo em Português | LILACS | ID: lil-108199

RESUMO

O estudo químico da madeira de Callistene major Mart. (Vochysiaceae) conduziu a três compostos naturais: ácidos 3,3'-di-0-metyl élagico e 3'-0-metil-3,4-0,0-metilideno élagico e fridelina.


Assuntos
Ácido Elágico/síntese química , Madeira , Brasil , Química
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