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1.
Bioorg Chem ; 67: 105-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27317888

RESUMO

Rivastigmine is a very important drug prescribed for the treatment of Alzheimer's disease (AD) symptoms. It is a dual inhibitor, in that it inhibits both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). For our screening program on the discovery of new rivastigmine analogue hits for human butyrylcholinesterase (hBuChE) inhibition, we investigated the interaction of this inhibitor with BuChE using the complimentary approach of the biophysical method, saturation transfer difference (STD)-NMR and molecular docking. This allowed us to obtain essential information on the key binding interactions between the inhibitor and the enzyme to be used for screening of hit compounds. The main conclusions obtained from this integrated study was that the most dominant interactions were (a) H-bonding between the carbamate carbonyl of the inhibitor and the NH group of the imidazole unit of H434, (b) stacking of the aromatic unit of the inhibitor and the W82 aromatic unit in the choline binding pocket via π-π interactions and (c) possible CH/π interactions between the benzylic methyl group and the N-methyl groups of the inhibitor and W82 of the enzyme.


Assuntos
Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Simulação de Acoplamento Molecular , Rivastigmina/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Rivastigmina/síntese química , Rivastigmina/química , Estereoisomerismo , Relação Estrutura-Atividade
2.
Bioorg Chem ; 67: 1-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27231829

RESUMO

A library of isoquinolinone and azepanone derivatives were screened for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activity. The strategy adopted included (a) in vitro biological assays, against eel AChE (EeAChE) and equine serum BuChE (EqBuChE) in order to determine the compounds IC50 and their dose-response activity, consolidated by (b) molecular docking studies to evaluate the docking poses and interatomic interactions in the case of the hit compounds, validated by STD-NMR studies. Compound (1f) was identified as one of these hits with an IC50 of 89.5µM for EeAChE and 153.8µM for EqBuChE, (2a) was identified as a second hit with an IC50 of 108.4µM (EeAChE) and 277.8µM (EqBuChE). In order to gain insights into the binding mode and principle active site interactions of these molecules, (R)-(1f) along with 3 other analogues (also as the R-enantiomer) were docked into both RhAChE and hBuChE models. Galantamine was used as the benchmark. The docking study was validated by performing an STD-NMR study of (1f) with EeAChE using galantamine as the benchmark.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Azepinas/farmacologia , Inibidores da Colinesterase/farmacologia , Colinesterases/metabolismo , Isoquinolinas/farmacologia , Simulação de Acoplamento Molecular , Doença de Alzheimer/enzimologia , Azepinas/síntese química , Azepinas/química , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Isoquinolinas/síntese química , Isoquinolinas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Relação Estrutura-Atividade
3.
Microsc Microanal ; 21(1): 84-90, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25252680

RESUMO

Different compounds of edible mushrooms are responsible for their bioactivity. The ability to synthesize polysaccharides, namely protein-polysaccharide (PPS) complexes, is related to the antioxidant capacity of these compounds and present great interest in preventing a number of diseases, including cancer, cardiovascular and auto-immune diseases, and accelerated aging. Amanita ponderosa are wild edible mushrooms that grow in Mediterranean "montado" areas [Portuguese name given to cork oak (Quercus suber) and holm oak (Quercus ilex) forests]. The aim of this study was to evaluate the production of PPS complexes obtained from A. ponderosa cultures using a new microanalytical approach to quickly and easily monitor the production process. Microanalysis using Fourier-transform infrared using attenuated total reflection and Raman spectroscopy of PPS samples showed spectra compatible with identification of this type of compound in culture extracts. PPS separated by size-exclusion chromatography showed seven main complexes. Molecular weights of the main PPS complexes isolated from cultures ranged between 1.5 and 20 kDa and did not present toxicity against Artemia salina, demonstrating the potential of A. ponderosa as a source of biologically active compounds with nutraceutical value. Application of this microanalytical approach to monitoring the production of PPS compounds can be successfully applied in biotechnological processes.


Assuntos
Amanita/metabolismo , Proteínas Fúngicas/química , Polissacarídeos/química , Amanita/química , Amanita/crescimento & desenvolvimento , Meios de Cultura/química , Meios de Cultura/metabolismo , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Peso Molecular , Polissacarídeos/isolamento & purificação , Polissacarídeos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
4.
Food Chem Toxicol ; 133: 110747, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377137

RESUMO

Three autochthonous flavouring herbs from Alentejo (Portugal), Calamintha nepeta (syn. Clinopodium nepeta), Origanun virens and Thymus mastichina, were selected to evaluate toxicological, antioxidant, antiproliferative and antimicrobial potential of their essential oils (EOs). C. nepeta and T. mastichina EOs showed a high content of oxygenated monoterpenes (86-91%) while O. virens had similar content of oxygenated and hydrocarbon monoterpenes (45%). Toxicological assessment suggests high activity against A. salina (31.8 < CL50 < 128.4 mg/L) and very low toxicity in Swiss mice (DL50 ≥ 1500 mg/kg). EOs showed high antioxidant ability by DPPH radical scavenging assay (0.1-0.6 mg QE/mL EO), total reducing power method (0.2-1.7 mg QE/mL EO) and ß-carotene/linoleic acid system (11-501 mg QE/mL EO). An important antiproliferative effect against human breast tumour cell line was observed (88.9 < EC50 < 108.5 mg/L). Moreover, EOs presented a large antibacterial spectrum. Results point out the low toxicity and high antioxidant, antiproliferative and antimicrobial activities of EOs of these endemic aromatic plants, suggesting their potential use in biotechnological, food and/or pharmaceutical industries.


Assuntos
Óleos Voláteis/farmacologia , Óleos Voláteis/toxicidade , Óleos de Plantas/farmacologia , Óleos de Plantas/toxicidade , Animais , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Antioxidantes/farmacologia , Antioxidantes/toxicidade , Artemia/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Nepeta/química , Origanum/química , Portugal , Thymus (Planta)/química
5.
Int J Anal Chem ; 2018: 5265291, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29623092

RESUMO

Amanita ponderosa are wild edible mushrooms that grow in some microclimates of Iberian Peninsula. Gastronomically this species is very relevant, due to not only the traditional consumption by the rural populations but also its commercial value in gourmet markets. Mineral characterisation of edible mushrooms is extremely important for certification and commercialization processes. In this study, we evaluate the inorganic composition of Amanita ponderosa fruiting bodies (Ca, K, Mg, Na, P, Ag, Al, Ba, Cd, Cr, Cu, Fe, Mn, Pb, and Zn) and their respective soil substrates from 24 different sampling sites of the southwest Iberian Peninsula (e.g., Alentejo, Andalusia, and Extremadura). Mineral composition revealed high content in macroelements, namely, potassium, phosphorus, and magnesium. Mushrooms showed presence of important trace elements and low contents of heavy metals within the limits of RDI. Bioconcentration was observed for some macro- and microelements, such as K, Cu, Zn, Mg, P, Ag, and Cd. A. ponderosa fruiting bodies showed different inorganic profiles according to their location and results pointed out that it is possible to generate an explanatory model of segmentation, performed with data based on the inorganic composition of mushrooms and soil mineral content, showing the possibility of relating these two types of data.

6.
Nat Prod Res ; 31(18): 2183-2187, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28076987

RESUMO

Essential oils (EOs) and aqueous extracts of aerial parts of four aromatic species, Calamintha nepeta, Foeniculum vulgare, Mentha spicata and Thymus mastichina, from southwest of Portugal were characterised chemically and analysed in order to evaluate their antioxidant potential and cholinesterase inhibitory activities. The main components of EOs were oxygenated monoterpenes, and aqueous extracts were rich in phenol and flavonoid compounds. EOs and aqueous extracts presented a high antioxidant potential, with ability to protect the lipid substrate, free radical scavenging and iron reducing power. Furthermore, EOs and extracts showed AChE and BChE inhibitory activities higher than rivastigmine, the standard drug. Results suggested the potential use of EOs and aqueous extracts of these flavouring herbs as nutraceutical or pharmaceutical preparations to minimise the oxidative stress and the progression of degenerative diseases.


Assuntos
Antioxidantes/farmacologia , Inibidores da Colinesterase/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/química , Inibidores da Colinesterase/química , Avaliação Pré-Clínica de Medicamentos/métodos , Flavonoides/análise , Aromatizantes/química , Foeniculum/química , Lamiaceae , Mentha spicata/química , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Fenóis/análise , Extratos Vegetais/química , Portugal , Thymus (Planta)/química
7.
Braz J Microbiol ; 44(2): 657-64, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24294266

RESUMO

Stone pine (Pinus pinea L.), like other conifers, forms ectomycorrhizas (ECM), which have beneficial impact on plant growth in natural environments and forest ecosystems. An in vitro co-culture of stone pine microshoots with pure mycelia of isolated ECM sporocarps was used to overcome the root growth cessation not only in vitro but also to improve root development during acclimation phase. Pisolithus arhizus (Scop.) Rauschert and Lactarius deliciosus (L. ex Fr.) S.F. Gray fungi, were collected, pure cultured and used in in vitro co-culture with stone pine microshoots. Samples of P. arhizus and L. deliciosus for the in vitro co-cultures were collected from the pine stands southwest Portugal. The in situ characterization was based on their morphotypes. To confirm the identity of the collected material, ITS amplification was applied using the pure cultures derived from the sporocarps. Additionally, a molecular profile using PCR based genomic fingerprinting comparison was executed with other genera of Basidiomycetes and Ascomycetes. Our results showed the effectiveness of the techniques used to amplify DNA polymorphic sequences, which enhances the characterization of the genetic profile of ECM fungi and also provides an option to verify the fungus identity at any stage of plant mycorrhization.


Assuntos
Micorrizas/classificação , Micorrizas/isolamento & purificação , Pinus/microbiologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Dados de Sequência Molecular , Micorrizas/genética , Micorrizas/crescimento & desenvolvimento , Filogenia , Portugal , Análise de Sequência de DNA
8.
Bioresour Technol ; 102(2): 1496-502, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20801027

RESUMO

The combined effect of incubation time (IT) and aspartic acid concentration (AA) on the predicted biomass concentration (BC), Bacillus sporulation (BS) and anti-fungal activity of compounds (AFA) produced by Bacillus amyloliquefaciens CCMI 1051, was studied using Artificial Neural Networks (ANNs). The values predicted by ANN were in good agreement with experimental results, and were better than those obtained when using Response Surface Methodology. The database used to train and validate ANNs contains experimental data of B. amyloliquefaciens cultures (AFA, BS and BC) with different incubation times (1-9 days) using aspartic acid (3-42 mM) as nitrogen source. After the training and validation stages, the 2-7-6-3 neural network results showed that maximum AFA can be achieved with 19.5 mM AA on day 9; however, maximum AFA can also be obtained with an incubation time as short as 6 days with 36.6 mM AA. Furthermore, the model results showed two distinct behaviors for AFA, depending on IT.


Assuntos
Antifúngicos/síntese química , Inteligência Artificial , Bacillus/citologia , Biotecnologia/métodos , Antifúngicos/farmacologia , Ácido Aspártico/análise , Bacillus/efeitos dos fármacos , Bacillus/fisiologia , Biomassa , Bases de Dados como Assunto , Redes Neurais de Computação , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/metabolismo , Fatores de Tempo
9.
Braz. j. microbiol ; 44(2): 657-665, 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-688573

RESUMO

Stone pine (Pinus pinea L.), like other conifers, forms ectomycorrhizas (ECM), which have beneficial impact on plant growth in natural environments and forest ecosystems. An in vitro co-culture of stone pine microshoots with pure mycelia of isolated ECM sporocarps was used to overcome the root growth cessation not only in vitro but also to improve root development during acclimation phase. Pisolithus arhizus (Scop.) Rauschert and Lactarius deliciosus (L. ex Fr.) S.F. Gray fungi, were collected, pure cultured and used in in vitro co-culture with stone pine microshoots. Samples of P. arhizus and L. deliciosus for the in vitro co-cultures were collected from the pine stands southwest Portugal. The in situ characterization was based on their morphotypes. To confirm the identity of the collected material, ITS amplification was applied using the pure cultures derived from the sporocarps. Additionally, a molecular profile using PCR based genomic fingerprinting comparison was executed with other genera of Basidiomycetes and Ascomycetes. Our results showed the effectiveness of the techniques used to amplify DNA polymorphic sequences, which enhances the ­characte­rization of the genetic profile of ECM fungi and also provides an option to verify the fungus identity at any stage of plant mycorrhization.


Assuntos
Micorrizas/classificação , Micorrizas/isolamento & purificação , Pinus/microbiologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Dados de Sequência Molecular , Micorrizas/genética , Micorrizas/crescimento & desenvolvimento , Filogenia , Portugal , Análise de Sequência de DNA
10.
Braz. j. microbiol ; 44(2): 667-670, 2013.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1469598

RESUMO

Stone pine (Pinus pinea L.), like other conifers, forms ectomycorrhizas (ECM), which have beneficial impact on plant growth in natural environments and forest ecosystems. An in vitro co-culture of stone pine microshoots with pure mycelia of isolated ECM sporocarps was used to overcome the root growth cessation not only in vitro but also to improve root development during acclimation phase. Pisolithus arhizus (Scop.) Rauschert and Lactarius deliciosus (L. ex Fr.) S.F. Gray fungi, were collected, pure cultured and used in in vitro co-culture with stone pine microshoots. Samples of P. arhizus and L. deliciosus for the in vitro co-cultures were collected from the pine stands southwest Portugal. The in situ characterization was based on their morphotypes. To confirm the identity of the collected material, ITS amplification was applied using the pure cultures derived from the sporocarps. Additionally, a molecular profile using PCR based genomic fingerprinting comparison was executed with other genera of Basidiomycetes and Ascomycetes. Our results showed the effectiveness of the techniques used to amplify DNA polymorphic sequences, which enhances the ­characte­rization of the genetic profile of ECM fungi and also provides an option to verify the fungus identity at any stage of plant mycorrhization.


Assuntos
Bioensaio , Pinus , Filogenia , Fungos
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