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1.
Nat Prod Res ; 36(13): 3450-3454, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33287568

RESUMO

This work aimed to carry out phytochemical prospecting and evaluate the antioxidant potential of Diplopterys pubipetala, a species of Malpighiaceae family that has not yet been studied.In qualitative analyses of hydroethanolic extracts of leaves and stems were detected the presence of flavonoids, alkaloidsand terpenes. The histochemical evaluation evidenced a greater distribution of these compounds in the tissues of leaf when compared with those of stem. The analysis by mass spectrometry allowed the identification of prenylated xanthones and glycoside flavonoids that have not yet been reported in the literature. The antioxidant activity of the stem extract was considered moderate (IAA = 0.79), but the leaves presented a strong antioxidant activity (IAA = 1.6). In this work we present information about the phytochemicals of D. pubipetala, showing that the species is promising in obtaining compounds with medicinal potential mainly antioxidant potential.


Assuntos
Malpighiaceae , Antioxidantes/química , Flavonoides/química , Malpighiaceae/química , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Folhas de Planta/química
2.
Braz Oral Res ; 32: e41, 2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29846389

RESUMO

The aim of this study was to evaluate in vitro the antifungal, antibiofilm and antiproliferative activities of the extract from the leaves of Guapira graciliflora Mart. The phytochemical characterization of the extract was performed using electrospray ionization mass spectrometry (ESI-MS). The antimicrobial activity of the extract and its fractions was evaluated using the broth microdilution method against species of Candida. The inhibition of C. albicans biofilm was evaluated based on the number of colony-forming units (CFU) and metabolic activity (MTT). The antiproliferative activity of the extract and its fraction was evaluated in the presence of human tumor and non-tumor cells, and the cytotoxicity of the extract was determined on the RAW 264.7 macrophage line - both using the sulforhodamine B method. The phytochemical characterization indicated the presence of the flavonoids rutin and kaempferol. The extract and the methanol fraction exhibited moderate antifungal activity against C. albicans, C. krusei, and C. glabrata, and strong activity against C. dubliniensis. In the biofilms at 24 and 48 hours, the concentration of 12500 µg/mL of the extract was the most effective at reducing the number of CFU s/mL (44.4% and 42.9%, respectively) and the metabolic activity of C. albicans cells (34.6% and 52%, respectively). The extract and its fractions had no antiproliferative effect on the tumor lines tested, with mean activity (log GI50) equal to or greater than 1.71 µg/mL. Macrophage cell viability remained higher than 80% for concentrations of the extract of up to 62.5 µg/mL. G. graciliflora has flavonoids in its chemical composition and demonstrates potential antifungal and antibiofilm activity, with no evidence of a significant change in the viability of human tumor and non-tumor cell lines.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Nyctaginaceae/química , Extratos Vegetais/farmacologia , Antifúngicos/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Dose Letal Mediana , Testes de Sensibilidade Microbiana
3.
Braz. oral res. (Online) ; 32: e41, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889473

RESUMO

Abstract: The aim of this study was to evaluate in vitro the antifungal, antibiofilm and antiproliferative activities of the extract from the leaves of Guapira graciliflora Mart. The phytochemical characterization of the extract was performed using electrospray ionization mass spectrometry (ESI-MS). The antimicrobial activity of the extract and its fractions was evaluated using the broth microdilution method against species of Candida. The inhibition of C. albicans biofilm was evaluated based on the number of colony-forming units (CFU) and metabolic activity (MTT). The antiproliferative activity of the extract and its fraction was evaluated in the presence of human tumor and non-tumor cells, and the cytotoxicity of the extract was determined on the RAW 264.7 macrophage line - both using the sulforhodamine B method. The phytochemical characterization indicated the presence of the flavonoids rutin and kaempferol. The extract and the methanol fraction exhibited moderate antifungal activity against C. albicans, C. krusei, and C. glabrata, and strong activity against C. dubliniensis. In the biofilms at 24 and 48 hours, the concentration of 12500 µg/mL of the extract was the most effective at reducing the number of CFU s/mL (44.4% and 42.9%, respectively) and the metabolic activity of C. albicans cells (34.6% and 52%, respectively). The extract and its fractions had no antiproliferative effect on the tumor lines tested, with mean activity (log GI50) equal to or greater than 1.71 µg/mL. Macrophage cell viability remained higher than 80% for concentrations of the extract of up to 62.5 µg/mL. G. graciliflora has flavonoids in its chemical composition and demonstrates potential antifungal and antibiofilm activity, with no evidence of a significant change in the viability of human tumor and non-tumor cell lines.


Assuntos
Candida/efeitos dos fármacos , Extratos Vegetais/farmacologia , Biofilmes/efeitos dos fármacos , Nyctaginaceae/química , Proliferação de Células/efeitos dos fármacos , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Sobrevivência Celular/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Dose Letal Mediana , Antifúngicos/isolamento & purificação
4.
Talanta ; 173: 22-27, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28602187

RESUMO

Biodiesel has been introduced as an energetic matrix in several countries around the world. However, the affinity of biodiesel with the components of petrodiesel engines is a growing concern. In order to obtain information regarding the effect of biodiesel on the rubber structure, nuclear magnetic resonance technics under a new technology named as comprehensive multiphase (CMP NMR) and the imaging through desorption electrospray ionization mass spectrometry (DESI-MS imaging) were used. The 1H CMP-DOSY NMR showed the entrapped fuel into the rubber cavities, which the higher constraint caused by the rubber structure is related to the smaller diffusion coefficient. The less affected type of rubber by biodiesel was ethylene-propylene-diene monomer (EPDM), and the most affected was synthetic rubber nitrile (NBR). The 13C CMP MAS-SPE experiments also confirmed that the internal region of EPDM was less accessible to the biodiesel molecules (no fuels detected) while other rubbers were more susceptible to the penetration of the fuel. DESI-MS imaging revealed for the first time the topography of the rubbers exposed to fuels. The biodiesel molecules entrapped at the EPDM and NBR pores were in oxidized form, which might degrade the rubber structure at long exposure time. The employed technics enabled the study of dynamic and molecular structure of the mixing complex multiphase. The DOSY under CMP used in this study could prove helpful in assessing the interactions throughout all physical phases (liquid, solid, and gel or semi-solid) by observing swellability caused by the fuel in the rubber. In addition, the DESI-MS was especially valuable to detect the degradation products of biodiesel entangled at the rubber structure. In our knowledge, this was the first report in which chemical changes of commercial rubbers induced by biodiesel and petrodiesel were investigated by means of DESI-MS and DOSY NMR.

5.
Reprod Fertil Dev ; 29(6): 1217-1230, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27220988

RESUMO

Dietary rumen-protected polyunsaturated fatty acids (PUFAs) rich in linoleic acid (LA) may affect embryo yield, and LA can modulate the molecular mechanisms of lipid uptake in bovine blastocysts produced in vitro. In embryos, membrane lipids, such as phosphatidylcholines (PCs) and sphingomyelins (SMs), affect cryopreservation success. The aim of the present study was to evaluate embryonic developmental rates after the IVF of oocytes retrieved from Nellore heifers fed for approximately 90 days with rumen-protected PUFAs rich in LA. In addition, we evaluated embryo cryotolerance and the membrane structure lipid composition using matrix-assisted laser desorption ionisation mass spectrometry of fresh and vitrified embryos. Embryo development to the blastocyst stage (mean 43.2%) and embryo survival after vitrification and warming (mean 79.3%) were unaffected by diet. The relative abundance of one lipid species (PC ether (PCe; 38:2, which means that this lipid has 38 carbon atoms and 2 double bonds in the fatty acyl residues) was increased after PUFAs supplementation. However, 10 ions were affected by cryopreservation; ions consistent with PC 32:0, PC 34:1, SM 24:1, PC 40:6 or PC 42:9, PC plasmalogen (PCp) 44:10 or PC 42:7, triacylglycerol (TAG) 54:9 and a not assigned ion (m/z 833.2) were lower in blastocysts that survived to the cryopreservation process compared with fresh blastocysts, whereas the abundance of the ions PC 36:3 or PC 34:0, PCe 38:2 or PC 36:6 and PC 36:5 or PCe 38:1 were increased after cryopreservation. Thus, the results demonstrate that the mass spectrometry profiles of PC, SM and TAG species differ significantly in bovine blastocysts upon cryopreservation. Because the lipid ion abundances of fresh and vitrified-warmed embryos were distinct, they can be used as potential markers of post-cryopreservation embryonic survival.


Assuntos
Criopreservação/veterinária , Gorduras Insaturadas na Dieta/administração & dosagem , Ectogênese , Embrião de Mamíferos/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Lipídeos de Membrana/metabolismo , Oocistos/metabolismo , Animais , Animais Endogâmicos , Blastocisto , Brasil , Bovinos , Estudos Cross-Over , Embrião de Mamíferos/citologia , Feminino , Fertilização in vitro/veterinária , Técnicas de Maturação in Vitro de Oócitos/veterinária , Ácido Linoleico/administração & dosagem , Ácido Linoleico/metabolismo , Masculino , Lipídeos de Membrana/química , Oocistos/citologia , Oocistos/isolamento & purificação , Recuperação de Oócitos/veterinária , Plasmalogênios/química , Plasmalogênios/metabolismo , Preservação do Sêmen/veterinária , Vitrificação
6.
J Assist Reprod Genet ; 33(12): 1571-1583, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27614633

RESUMO

PURPOSE: The goal for the present study was to implement a technique for protein extraction and identification in human cumulus cells (CCs). METHODS: Forty samples of CCs were collected after ovum pick-up from patients undergoing intracytoplasmic sperm injection (ICSI). Samples were split into the blastocyst group (n = 10), including patients in which all embryos converted into blastocysts, and the non-blastocyst group (n = 10), including patients in which none of the embryos reached the blastocyst stage or the positive-pregnancy (n = 10) and negative-pregnancy group (n = 10). Proteins were extracted and injected into a liquid chromatography system coupled to a mass spectrometer. The spectra were processed and used to search a database. RESULTS: There were 87 different proteins in samples from the blastocyst and non-blastocyst groups, in which 30 were exclusively expressed in the blastocyst group and 17 in the non-blastocyst group. Among the 72 proteins detected in the pregnancy groups, 19 were exclusively expressed in the positive, and 16 were exclusively expressed in the negative-pregnancy group. CONCLUSIONS: CC proteomics may be useful for predicting pregnancy success and the identification of patients that should be included in extended embryo culture programs.


Assuntos
Blastocisto/metabolismo , Células do Cúmulo/metabolismo , Desenvolvimento Embrionário/genética , Biossíntese de Proteínas/genética , Blastocisto/fisiologia , Cromatografia Líquida , Células do Cúmulo/fisiologia , Transferência Embrionária/métodos , Feminino , Fertilização in vitro , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Oócitos/metabolismo , Oócitos/fisiologia , Gravidez , Proteômica
7.
JBRA Assist Reprod ; 20(4): 227-231, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28050958

RESUMO

OBJECTIVE: To identify lipid markers of blastocyst implantation and ongoing pregnancy by day three culture medium mass spectrometry (MS) fingerprinting. METHODS: For this study, 33 culture media samples were harvested on day three, from 22 patients undergoing day five embryo transfers. All embryos achieved the blastocyst stage and were split into groups based on their implantation (Negative Implantation, n= 14 and Positive Implantation, n= 19). The positive implantation cycles resulted in successful ongoing pregnancies. The lipid extraction was performed by the Bligh-Dyer protocol and mass spectra were obtained with a direct infusion into a Q-Tof mass spectrometer. The data obtained was analyzed by Principal Component Analysis (PCA) and Partial Least Square Discrimination Analysis (PLS-DA). The statistical analysis was performed using the Metabo-Analyst 2.0. RESULTS: The variable importance in the projection (VIP) plot of the PLS-DA provided a list of four ions, in the positive mode, with an area under the curve (AUC) of 73.5%; and eight ions, in the negative mode, with and AUC of 72.0%. For both positive and negative modes, possible biomarkers for the negative implantation were identified by the lipidmaps: phosphoethanolamine, dicarboxylic acids, glycerophosphoglycerol, glycerophosphocholine, glicerophosphoinositol, phosphoethanolamine and unsaturated fat acids. The other ions were not identified. These lipids are involved in the GPI anchor biosynthesis and synthesis of lycerophospholipids and phosphate inositol. CONCLUSION: MS fingerprinting is useful to identify blastocysts that fail to implant, and therefore this technique could be incorporated into the laboratory routine, adjunct to morphology evaluation to identify embryos that should not be transferred.

8.
Rapid Commun Mass Spectrom ; 29(16): 1530-4, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-26212168

RESUMO

RATIONALE: Citrus aurantium L. is a plant belonging to the Rutaceae family, whose extracts are extensively used in weight management products and as thermogenic agents. Here we present two methodologies to analyse the extracts obtained from the peels of Citrus aurantium L. that usually require multiple sample preparation and detection steps. METHODS: Polar compounds of the crude extract from the peels of Citrus aurantium L. (Rutaceae) were investigated by direct infusion electrospray ionization mass spectrometry (ESI-MS) and high-performance thin-layer chromatography (HPTLC) coupled to desorption electrospray ionization mass spectrometry (DESI-MS). ESI-MS was performed in both positive and negative ion modes. Molecular imaging of the HPTLC plates was used for the direct analysis of the phytocompounds present in the crude extract from the peels of Citrus aurantium L. by DESI-MS imaging. RESULTS: Characteristic mass spectra with many diagnostic ions were obtained from the extract analysis, allowing a fast and reliable identification of these species. Tandem mass spectrometry (MS/MS) was employed to confirm the identity of specific metabolites. CONCLUSIONS: HPTLC/DESI-MS imaging is a relatively fast, versatile, and efficient technique for natural product analysis, since many more ions are observed than with the direct infusion ESI-MS. The MS/MS technique provided information about the component structures, revealing the presence of important bioactive components. The application of DESI-MS imaging may contribute to the improvement identification and characterization of pharmacologically active compounds in phytochemistry.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Citrus/química , Frutas/química , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Compostos Fitoquímicos/química
9.
JBRA Assist Reprod ; 19(3): 119-24, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27203089

RESUMO

OBJECTIVE: To identify lipid markers of blastocyst formation by day three culture medium mass spectrometry (MS) fingerprinting. METHODS: For this study, 50 embryo samples from culture media were harvested on day three, from patients undergoing embryo transfers on day five. Samples were split into groups based on their degree of expansion and hatching status on day five (Complete-Blastocyst, n=25 and No-Blastocyst, n=25) and its secretomes were analysed by MS. Mass spectra fingerprinting was acquired using a Q-Tof spectrometer (LC-MS, Agilent 6550 iFunnel Q-TOF) equipped with an automated injector. The data was analysed using the principal component analysis (PCA) followed by a partial least square discrimination analysis (PLS-DA), combined with variable influence in the projection (VIP) scores. RESULTS: In total, there were 1,657 ions found, in which 165 ions were differently expressed between groups, with a fold chance ≥ 4x and P<0.001, in the t-test. PLS-DA showed a clear separation between the groups and among 15 VIPs selected by the program, 13 of them were highly expressed in the Complete-Blastocyst Group and two were expressed in the No-Blastocyts Group. Besides embryo status on day five, the PLS-DA was also able to classify samples according to patients' age. Lipids supposedly highly expressed in the Complete-Blastocyst Group included: isoprenoids, diacylglycerols, sterols, fatty esters, secosteroids, phosphosphingolipids, glycerophosphates and diacylglycerophosphates, while fatty amides were suggested to be highly expressed in the No-Blastocysts Group. CONCLUSIONS: Day three culture medium MS is a promising approach for the identification of embryos that should be cultured until day five.

10.
Methods Mol Biol ; 1203: 63-77, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25361667

RESUMO

Desorption electrospray ionization (DESI) allows the direct analysis of ordinary objects or preprocessed samples under ambient conditions. Among other applications, DESI is used to identify and to record spatial distributions of small molecules in situ, sliced or imprinted biological tissue. Manipulation of the chemistry accompanying ambient analysis ionization can be used to optimize chemical analysis, including molecular imprinting. Images are obtained by continuously moving the sample relative to the DESI sprayer and the inlet of the mass spectrometer. The acquisition time depends on the size of the surface to be analyzed and on the desired resolution.


Assuntos
Imagem Molecular/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Métodos Analíticos de Preparação de Amostras , Animais , Fragaria/citologia , Fragaria/metabolismo , Frutas/citologia , Frutas/metabolismo , Ginkgo biloba/citologia , Ginkgo biloba/metabolismo , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Solventes/química , Temperatura , Peixe-Zebra/metabolismo
11.
Zygote ; 23(5): 732-41, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25213102

RESUMO

This study aimed to evaluate the impact of vitrification on membrane lipid profile obtained by mass spectrometry (MS) of in vitro-produced bovine embryos. Matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) has been used to obtain individual embryo membrane lipid profiles. Due to conditions of analysis, mainly membrane lipids, most favorably phosphatidylcholines (PCs) and sphingomyelins (SMs) have been detected. The following ions described by their mass-to-charge ratio (m/z) and respective attribution presented increased relative abundance (1.2-20×) in the vitrified group: 703.5 [SM (16:0) + H]+; 722.5 [PC (40:3) + Na]+; 758.5 [PC (34:2) + H]+; 762.5 [PC (34:0) + H]+; 790.5 [PC (36:0) + H]+ and 810.5 [PC (38:4) + H]+ and/or [PC (36:1) + Na]+. The ion with a m/z 744.5 [PCp (34:1) and/or PCe (34:2)] was 3.4-fold more abundant in the fresh group. Interestingly, ions with m/z 722.5 or 744.5 indicate the presence of lipid species, which are more resistant to enzymatic degradation as they contain fatty acyl residues linked through ether type bonds (alkyl ether or plasmalogens, indicated by the lowercase 'e' and 'p', respectively) to the glycerol structure. The results indicate that cryopreservation impacts the membrane lipid profile, and that these alterations can be properly monitored by MALDI-MS. Membrane lipids can therefore be evaluated by MALDI-MS to monitor the effect of cryopreservation on membrane lipids, and to investigate changes in lipid profile that may reflect the metabolic response to the cryopreservation stress or changes in the environmental conditions.


Assuntos
Biomarcadores/análise , Embrião de Mamíferos/metabolismo , Fertilização in vitro/veterinária , Técnicas de Maturação in Vitro de Oócitos/veterinária , Lipídeos de Membrana/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Vitrificação , Animais , Bovinos , Embrião de Mamíferos/citologia , Feminino
12.
J Mass Spectrom ; 48(7): 774-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23832933

RESUMO

Desorption electrospray ionization mass spectrometry (DESI-MS) is employed in the forensic analysis of chemical components present in condoms and imaging of latent fingerprints as circumstantial evidence of sexual assault. Polymers such as nonoxynol-9, polyethylene glycol, and polydimethylsiloxane, as well as small molecules additives such as N-methylmorpholine, N-octylamine, N,N-dibutyl formamide, and isonox 132, commonly used in lubricated condom formulations, were successfully characterized by DESI. The results suggest that DESI-MS is useful for identification of this type of evidence, and it has advantages over conventional extractive techniques, in terms of speed of analysis and ease of use.


Assuntos
Preservativos , Medicina Legal/métodos , Delitos Sexuais , Espectrometria de Massas por Ionização por Electrospray/métodos , Aminas/análise , Aminas/química , Dermatoglifia , Dimetilpolisiloxanos/análise , Dimetilpolisiloxanos/química , Humanos , Morfolinas/análise , Morfolinas/química , Nonoxinol/análise , Nonoxinol/química , Borracha/química
13.
J Am Soc Mass Spectrom ; 24(6): 956-65, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23605686

RESUMO

Imprints of potato sprout (Solanum tuberosum L.), gingko leaves (Gingko biloba L.) and strawberries (Fragaria x ananassa Duch.) were successfully imaged by desorption electrospray ionization mass spectrometry (DESI-MS) on TLC plates through blotting assisted by heating and/or solvent extraction. Ion images showing the distribution of significant compounds such as glycoalkaloid toxins in potato sprout, ginkgolic acids and flavonoids in ginkgo leaves, and sugars and anthocyanidin in strawberry were obtained. Practical implications of this work include analysis of a wide range of irregular or soft materials by different imprinting conditions without requiring the addition of matrices or use of specific kinds of surfaces.


Assuntos
Imagem Molecular/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Acetonitrilas/química , Alcaloides/análise , Alcaloides/química , Carboidratos/análise , Carboidratos/química , Flavonoides/análise , Flavonoides/química , Fragaria/química , Ginkgo biloba/química , Temperatura Alta , Metanol/química , Folhas de Planta/química , Salicilatos/análise , Salicilatos/química , Solanum tuberosum/química , Solventes/química
14.
Reproduction ; 145(5): 453-62, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23404850

RESUMO

This study has evaluated the performance of a multivariate statistical model to predict embryo implantation potential by processing data from the chemical fingerprinting of culture medium samples used for human embryo culture. The culture medium for 113 embryos from 55 patients undergoing ICSI was collected after embryo transfer. The samples were split into positive (n=29) and negative (n=84) implantation groups according their implantation outcomes (100% or 0% implantation). The samples were individually diluted and analyzed by electrospray ionization mass spectrometry (ESI-MS). The m/z ratios and relative abundances of the major ions in each spectrum were considered for partial least square discriminant analysis. Data were divided into two subsets (calibration and validation), and the models were evaluated and applied to the validation set. A total of 5987 ions were observed in the groups. The multivariate statistical model described more than 82% of the data variability. Samples of the positive group were correctly identified with 100% probability and negative samples with 70%. The culture media used for embryos that were positive or negative for successful implantation showed specific biochemical signatures that could be detected in a fast, simple, and noninvasive way by ESI-MS. To our knowledge, this is the first report that uses MS fingerprinting to predict human embryo implantation potential. This biochemical profile could help the selection of the most viable embryo, improving single-embryo transfer and thus eliminating the risk and undesirable outcomes of multiple pregnancies.


Assuntos
Ectogênese , Implantação do Embrião , Transferência Embrionária , Proteínas Fetais/análise , Modelos Biológicos , Zigoto/metabolismo , Adulto , Calibragem , Estudos de Casos e Controles , Meios de Cultivo Condicionados/química , Análise Discriminante , Feminino , Proteínas Fetais/química , Proteínas Fetais/metabolismo , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Infertilidade Masculina/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mapeamento de Peptídeos , Espectrometria de Massas por Ionização por Electrospray , Injeções de Esperma Intracitoplásmicas
15.
Food Chem ; 135(3): 1855-60, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22953933

RESUMO

Commercial lecithins are composed mainly of phospholipids and triacylglycerols. The analysis of the commercial lecithins, including their fraction of phospholipids, normally involves laborious and expensive protocols. Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to be an efficient technique for the analysis of lipids. Samples of commercial lecithins including standards, refined, deoiled and modified soy lecithin were tested. Characteristic profiles of phosphatidylcholines and triacylglycerols are detected by EASI(+)-MS, whereas EASI(-)-MS provided phosphatidylethanolamines, glycophospholipids and free fatty acids profiles. Acetylated lecithins also displayed characteristic acetylated derivatives. EASI-MS data was also compared to MALDI-MS, and found to display richer compositional information. The industrial process applied to lecithin fabrication was also characterised via typical EASI-MS profiles. EASI-MS both in its positive and negative ion modes offers a direct, fast and efficient technique able to characterise commercial lecithin.


Assuntos
Lecitinas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Lecitinas/economia , Espectrometria de Massas por Ionização por Electrospray/instrumentação
16.
J Mass Spectrom ; 47(1): 1-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22282083

RESUMO

Venturi easy ambient sonic spray ionization mass spectrometry in both its liquid (V(L) -EASI-MS) and solid sample modes (V(S) -EASI-MS) is shown to provide nearly immediate and secure typification of woods, as demonstrated for Mahogany, an endangered and most valuable type of tropical wood. This reddish wood displays unique phytochemical markers (phragmalin-type limonoids) which are rapidly detected from the wood surface by V(S) -EASI-MS or from a simple methanol extract of a tiny wood chip by V(L) -EASI-MS. Unique profiles were obtained for Mahogany (Swietenia macrophylla) whereas genuine samples of six other similar types of woods, which are commonly falsified by artificial coloring and commercialized as Mahogany, display also typical but dissimilar pythochemical profiles as compared to that of the authentic wood. Variable and atypical chemical profiles were observed for artificially colored woods. Secure chemical characterization via V(S) -EASI-MS or V(s) -EASI-MS fingerprints of Mahogany and other types of woods with similar appearance should help to control the illegal logging and trade of this and other endangered woods and their falsification, and to create certified standards.


Assuntos
Meliaceae/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Madeira/classificação , Fracionamento Químico , Espécies em Perigo de Extinção , Limoninas/análise , Metanol , Árvores , Madeira/análise , Madeira/química
17.
Malar J ; 10: 112, 2011 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-21535894

RESUMO

BACKGROUND: To overcome the problem of increasing drug resistance, traditional medicines are an important source for potential new anti-malarials. Caesalpinia pluviosa, commonly named "sibipiruna", originates from Brazil and possess multiple therapeutic properties, including anti-malarial activity. METHODS: Crude extract (CE) was obtained from stem bark by purification using different solvents, resulting in seven fractions. An MTT assay was performed to evaluate cytotoxicity in MCF-7 cells. The CE and its fractions were tested in vitro against chloroquine-sensitive (3D7) and -resistant (S20) strains of Plasmodium falciparum and in vivo in Plasmodium chabaudi-infected mice. In vitro interaction with artesunate and the active C. pluviosa fractions was assessed, and mass spectrometry analyses were conducted. RESULTS: At non-toxic concentrations, the 100% ethanolic (F4) and 50% methanolic (F5) fractions possessed significant anti-malarial activity against both 3D7 and S20 strains. Drug interaction assays with artesunate showed a synergistic interaction with the F4. Four days of treatment with this fraction significantly inhibited parasitaemia in mice in a dose-dependent manner. Mass spectrometry analyses revealed the presence of an ion corresponding to m/z 303.0450, suggesting the presence of quercetin. However, a second set of analyses, with a quercetin standard, showed distinct ions of m/z 137 and 153. CONCLUSIONS: The findings show that the F4 fraction of C. pluviosa exhibits anti-malarial activity in vitro at non-toxic concentrations, which was potentiated in the presence of artesunate. Moreover, this anti-malarial activity was also sustained in vivo after treatment of infected mice. Finally, mass spectrometry analyses suggest that a new compound, most likely an isomer of quercetin, is responsible for the anti-malarial activity of the F4.


Assuntos
Antimaláricos/administração & dosagem , Antimaláricos/farmacologia , Caesalpinia/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Animais , Antimaláricos/isolamento & purificação , Antimaláricos/toxicidade , Artemisininas/farmacologia , Artesunato , Brasil , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Sinergismo Farmacológico , Humanos , Malária/tratamento farmacológico , Malária/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Casca de Planta/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Plantas Medicinais/química , Plasmodium chabaudi/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Quercetina/administração & dosagem , Quercetina/isolamento & purificação , Quercetina/farmacologia , Quercetina/toxicidade , Doenças dos Roedores/tratamento farmacológico , Doenças dos Roedores/parasitologia
18.
Int J Food Microbiol ; 142(1-2): 156-63, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20633943

RESUMO

Although the production of patulin in apple fruits is mainly by Penicillium expansum, there is no information on the ability of heat resistant moulds that may survive pasteurization to produce this mycotoxin in juice packages during storage and distribution. In this study, the production of patulin by Byssochlamys spp (Byssochlamys nivea FRR 4421, B. nivea ATCC 24008 and Byssochlamys fulva IOC 4518) in cloudy and clarified apple juices packaged in laminated paperboard packages or in polyethylene terephthalate bottles (PET) and stored at both 21 degrees C and 30 degrees C, was investigated. The three Byssochlamys strains were able to produce patulin in both cloudy and clarified apple juices. Overall, the lower the storage temperature, the lower the patulin levels and mycelium dry weight in the apple juices (p<0.05). The greatest variations in pH and degrees Brix were observed in the juices from which the greatest mycelium dry weights were recovered. The maximum levels of patulin recovered from the juices were ca. 150 microg/kg at 21 degrees C and 220 microg/kg at 30 degrees C. HPLC-UV, HPCL-DAD and mass spectrometry analyses confirmed the ability of B. fulva IOC 4518 to produce patulin. Due to the heat resistance of B. nivea and B. fulva and their ability to produce patulin either in PET bottles or in laminated paperboard packages, the control of contamination and the incidence of these fungi should be a matter of concern for food safety. Control measures taken by juice industries must also focus on controlling the ascospores of heat resistant moulds.


Assuntos
Bebidas/microbiologia , Byssochlamys/metabolismo , Embalagem de Alimentos , Malus/microbiologia , Patulina/metabolismo , Contaminação de Alimentos/análise , Patulina/análise , Temperatura
19.
J Nat Prod ; 73(6): 1180-3, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20476748

RESUMO

Phytochemical investigation of the bark of Guatteria hispida afforded three new alkaloids, 9-methoxy-O-methylmoschatoline (1), 9-methoxyisomoschatoline (2), and isocerasonine (3), along with 10 known alkaloids, 8-oxopseudopalmatine (4), O-methylmoschatoline (5), lysicamine (6), liriodenine (7), 10-methoxyliriodenine (8), nornuciferine (9), anonaine (10), xylopine (11), coreximine (12), and isocoreximine (13). The major compounds, 2, 6, 12, and 13, showed significant antioxidant capacity in the ORAC(FL) assay. Compounds 5, 6, and 7 were active against S. epidermidis and C. dubliniensis, with MIC values in the range 12.5-100 microg mL(-1).


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Guatteria/química , Plantas Medicinais/química , Alcaloides/química , Antibacterianos/química , Antifúngicos/química , Antioxidantes/química , Aporfinas/química , Brasil , Candida/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Casca de Planta/química , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos
20.
Analyst ; 135(4): 738-44, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20349539

RESUMO

A fast and reliable method is presented for the analysis of vegetable oils. Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to efficiently desorb and ionize the main oil constituents from an inert surface under ambient conditions and to provide comprehensive triacylglyceride (TAG) and free fatty acid (FFA) profiles detected mainly as either [TAG + Na](+) or [FFA-H](-) ions. EASI(+/-)-MS analysis is simple, easily implemented, requires just a tiny droplet of the oil and is performed without any pre-separation or chemical manipulation. It also causes no fragmentation of TAG ions hence diacylglyceride (DAG) and monoacylglyceride (MAG) profiles and contents can also be measured. The EASI(+/-)-MS profiles of TAG and FFA permit authentication and quality control and can be used, for instance, to access levels of adulteration, acidity, oxidation or hydrolysis of vegetable oils in general.


Assuntos
Ácidos Graxos/química , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Triglicerídeos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Ultrassom
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