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1.
Molecules ; 27(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36144693

RESUMO

The plant Miconia albicans (Sw.) Triana has been popularly used in Brazil to treat chronic inflammatory disturbances, such as osteoarthritis. This disease affects 250 million people worldwide, and is associated with intense pain and loss of articular function. There is a lack of information about the phytochemistry and bioactivity of M. albicans. Therefore, this study determined the chemical composition of some extracts and evaluated their cytotoxicity, along with their antioxidant and anti-inflammatory, activities using in vitro models. Aqueous and ethanolic extracts were prepared. Afterwards, a liquid-liquid partition was developed using chloroform, ethyl acetate, and n-butanol. The extracts were characterized by LC-MS, and their biological activities were evaluated on epithelial cells (Vero), tumoral hepatic cells (Hep-G2), and THP-1 macrophages. LC-MS analyses identified several flavonoids in all fractions, such as quercetin, myricetin, and their glycosides. The crude extracts and n-butanol fractions did not present cytotoxicity to the cells. The non-toxic fractions presented significant antioxidant activity when evaluated in terms of DPPH scavenging activity, lipid peroxidation, and ROS inhibition. THP-1 macrophages treated with the n-butanol fraction (250 µg/mL) released fewer pro-inflammatory cytokines, even in the presence of LPS. In the future, it will be necessary to identify the phytochemicals that are responsible for anti-inflammatory effects for the discovery of new drugs. In vivo studies on M. albicans extracts are still required to confirm their possible mechanisms of action.


Assuntos
Melastomataceae , 1-Butanol , Anti-Inflamatórios/química , Antioxidantes/química , Clorofórmio , Citocinas , Flavonoides/farmacologia , Glicosídeos , Humanos , Lipopolissacarídeos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Quercetina/farmacologia , Espécies Reativas de Oxigênio
2.
Acta Pharm ; 71(3): 383-398, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36654097

RESUMO

Pain is a common and distressing symptom of many diseases and its clinical treatment generally involves analgesics and anti-inflammatory drugs. This study evaluated the toxicity of Ilex paraguariensis A. St.-Hil. (Aquifoliaceae) aqueous extract (leaves, petioles and branches) and its performance in a nociceptive response. Hepatotoxicity, psycho-stimulant test and evaluation of enzyme markers for liver damage were also tested. Chromatographic analysis by UPLC-MS demonstrated a series of isomeric monocaffeoylquinic acids, isomers of dicaffeoylquinic acid, flavonol glycosides, and saponins. Phase I and II of nociception were obtained for meloxicam, dexamethasone and aqueous Ilex paraguariensis extract. Ilex paraguariensis extract concentration was negatively correlated (R = -0.887) with alanine aminotransferase (p < 0.05) in acetaminophen-induced hepatotoxicity test, indicating hepatoprotective activity of this extract. Ilex paraguariensis extract also presented analgesic properties equivalent to drugs that already have proven efficacy. Notably, the administration of multiple doses of Ilex paraguariensis extract was considered safe from the therapeutic point of view.

3.
J Ethnopharmacol ; 255: 112722, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32114165

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Euphorbia tirucalli L. is an African plant that grows well in Brazil. Individuals diagnosed with cancer frequently consume latex from E. tirucalli, dissolved in drinking water. In vitro studies confirm the antitumor potential of E. tirucalli latex, but in vivo evaluations are scarce. AIM OF THE STUDY: To evaluate the effect of intake of an aqueous solution of E. tirucalli latex on tumor growth, cachexia, and immune response in Walker 256 tumor-bearing rats. MATERIALS AND METHODS: Latex from E. tirucalli was collected and analyzed by LC-MS. Sixty male Wistar rats (age, 90 days) were randomly divided into four groups: C, control group (without tumor); W, Walker 256 tumor-bearing group; SW1, W animals but treated with 25 µL latex/mL water; and SW2, W animals but treated with 50 µL latex/mL water. Animals received 1 mL of latex solution once a day by gavage. After 15 d, animals were euthanized, tumor mass was determined, and glucose and triacylglycerol serum levels were measured by using commercial kits. Change in the body weight during tumor development was calculated, and proliferation capacity of tumor cells was assessed by the Alamar Blue assay. Phagocytosis and superoxide anion production by peritoneal macrophages and circulating neutrophils were analyzed by enzymatic and colorimetric assays. Data are analyzed by one-way ANOVA followed by Tukey's post-hoc test, with the significance level set at 5%. RESULTS: The analysis of the latex revealed the presence of triterpenes. The ingestion of the latex aqueous solution promoted 40% and 60% reduction of the tumor mass in SW1 and SW2 groups, respectively (p < 0.05). The proliferative capacity of tumor cells from SW2 group was 76% lower than that of cells from W group (p < 0.0001). Animals treated with latex gained, on average, 20 g (SW1) and 8 g (SW2) weight. Glucose and triacylglycerol serum levels in SW1 and SW2 animals were similar to those in C group rats. Peritoneal macrophages and blood neutrophils from SW1 and SW2 animals produced 30-40% less superoxide anions than those from W group animals (p < 0.05), but neutrophils from SW2 group showed an increased phagocytic capacity (20%, vs. W group). CONCLUSIONS: E. tirucalli latex, administered orally for 15 d, efficiently reduced tumor growth and cachexia in Walker 256 tumor-bearing rats. Decreased tumor cell proliferative capacity was one of the mechanisms involved in this effect. Further, the data suggest immunomodulatory properties of E. tirucalli latex. The results agree with folk data on the antitumor effect of latex ingestion, indicating that it may be useful as an adjunct in the treatment of cancer patients. For this, further in vivo studies in animal and human models need to be conducted.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Caquexia/prevenção & controle , Carcinoma 256 de Walker/tratamento farmacológico , Euphorbia , Látex/farmacologia , Extratos Vegetais/farmacologia , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Caquexia/sangue , Caquexia/imunologia , Caquexia/fisiopatologia , Carcinoma 256 de Walker/patologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Euphorbia/química , Látex/isolamento & purificação , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Extratos Vegetais/isolamento & purificação , Ratos Wistar , Triglicerídeos/sangue , Carga Tumoral/efeitos dos fármacos , Redução de Peso/efeitos dos fármacos
4.
J Pharm Biomed Anal ; 145: 821-830, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28826140

RESUMO

Croton cajucara Benth. is a medicinal plant popularly used in the Brazilian Amazonia, where it is known as sacaca, being consumed as tea, decoction or infusion of the leaves and stem bark. From a decoction of the leaves, a comprehensive phytochemical analysis was developed by liquid chromatography-mass spectrometry. Many compounds were identified for the first time in C. cajucara, such as O-glycosides of kaempferol and quercetin, flavonoid-C-glycosides, tannins and cinnamic acid derivatives. These compounds were fractionated by polarity and assayed for their anti-inflammatory activity, using a model of mice edema, induced by an intraplantar injection of carrageenan. All fractions exhibited anti-inflammatory properties.


Assuntos
Croton , Animais , Anti-Inflamatórios , Brasil , Camundongos , Compostos Fitoquímicos , Extratos Vegetais , Plantas Medicinais
5.
Int J Biol Macromol ; 95: 153-159, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27864055

RESUMO

Croton cajucara Benth. is a tree from the Amazon Forest, where it is known as sacaca. Its leaves and barks are used in medicinal preparations to treat different diseases, including gastric ulcers. The crude polysaccharide fraction (CCP), obtained from the hot aqueous extract of C. cajucara leaves, was able to promote gastroprotection on an ethanol induced gastric ulcer model. Therefore, a bioguided fractionation was performed to isolate the active polysaccharide fraction. After freezing-thawing, ultrafiltration and dialyses at 100, 50, and 25kDa cut-off membranes, fraction 25R was obtained. It contained glucose, galactose, rhamnose, arabinose, galacturonic acid and mannose in a 7:5:5:3:1:1 molar ratio approximately, and had a Mw of 42,840g/mol. Methylation analysis and NMR spectroscopy indicated that 25R is a very complex polysaccharide fraction containing type I rhamnogalacturonan, arabinan, type I arabinogalactan, type II arabinogalactan, rhamnan, starch and mannan. It was able to reduce ethanol-induced gastric ulcers in rats, through preservation of mucus and GSH levels.


Assuntos
Croton/química , Citoproteção/efeitos dos fármacos , Folhas de Planta/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Estômago/efeitos dos fármacos , Estômago/patologia , Animais , Antiulcerosos/química , Antiulcerosos/farmacologia , Antiulcerosos/uso terapêutico , Etanol/farmacologia , Feminino , Mucosa Gástrica/metabolismo , Polissacarídeos/uso terapêutico , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/metabolismo
6.
PLoS One ; 11(9): e0161926, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27603136

RESUMO

Whole genome sequencing and analyses of Ureaplasma diversum ATCC 49782 was undertaken as a step towards understanding U. diversum biology and pathogenicity. The complete genome showed 973,501 bp in a single circular chromosome, with 28.2% of G+C content. A total of 782 coding DNA sequences (CDSs), and 6 rRNA and 32 tRNA genes were predicted and annotated. The metabolic pathways are identical to other human ureaplasmas, including the production of ATP via hydrolysis of the urea. Genes related to pathogenicity, such as urease, phospholipase, hemolysin, and a Mycoplasma Ig binding protein (MIB)-Mycoplasma Ig protease (MIP) system were identified. More interestingly, a large number of genes (n = 40) encoding surface molecules were annotated in the genome (lipoproteins, multiple-banded antigen like protein, membrane nuclease lipoprotein and variable surface antigens lipoprotein). In addition, a gene encoding glycosyltransferase was also found. This enzyme has been associated with the production of capsule in mycoplasmas and ureaplasma. We then sought to detect the presence of a capsule in this organism. A polysaccharide capsule from 11 to 17 nm of U. diversum was observed trough electron microscopy and using specific dyes. This structure contained arabinose, xylose, mannose, galactose and glucose. In order to understand the inflammatory response against these surface molecules, we evaluated the response of murine macrophages J774 against viable and non-viable U. diversum. As with viable bacteria, non-viable bacteria were capable of promoting a significant inflammatory response by activation of Toll like receptor 2 (TLR2), indicating that surface molecules are important for the activation of inflammatory response. Furthermore, a cascade of genes related to the inflammasome pathway of macrophages was also up-regulated during infection with viable organisms when compared to non-infected cells. In conclusion, U. diversum has a typical ureaplasma genome and metabolism, and its surface molecules, including the identified capsular material, represent major components of the organism immunopathogenesis.


Assuntos
Genoma Bacteriano/genética , Interações Hospedeiro-Patógeno/genética , Infecções por Ureaplasma/genética , Ureaplasma/genética , Composição de Bases/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Inflamassomos/genética , Lipoproteínas/genética , Redes e Vias Metabólicas/genética , Anotação de Sequência Molecular , Mycoplasma/genética , Mycoplasma/patogenicidade , Fosfolipases/genética , Receptores Toll-Like/genética , Ureaplasma/patogenicidade , Infecções por Ureaplasma/microbiologia , Infecções por Ureaplasma/patologia , Urease/genética
7.
Int J Biol Macromol ; 91: 954-60, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27311502

RESUMO

The plant Arctium lappa L. is popularly used to relieve symptoms of inflammatory disorders. A crude polysaccharide fraction (SAA) resulting of aqueous extraction of A. lappa leaves showed a dose dependent anti-edematogenic activity on carrageenan-induced paw edema, which persisted for up to 48h. Sequential fractionation by ultrafiltration at 50kDa and 30kDa cut-off membranes yielded three fractions, namely RF50, RF30, and EF30. All these maintained the anti-edematogenic effect, but RF30 showed a more potent action, inhibiting 57% of the paw edema at a dose of 4.9mg/kg. The polysaccharide RF30 contained galacturonic acid, galactose, arabinose, rhamnose, glucose, and mannose in a 7:4:2:1:2:1 ratio and had a Mw of 91,000g/mol. Methylation analysis and NMR spectroscopy indicated that RF30 is mainly constituted by a type I rhamnogalacturonan branched by side chains of types I and II arabinogalactans, and arabinan.


Assuntos
Arctium/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Fracionamento Químico , Cromatografia em Gel , Edema/tratamento farmacológico , Edema/patologia , Feminino , Camundongos , Monossacarídeos/análise , Polissacarídeos/uso terapêutico , Espectroscopia de Prótons por Ressonância Magnética
8.
J Chromatogr A ; 1447: 64-71, 2016 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-27109198

RESUMO

Flavonol glycosides are important components of leaves from vascular plants. A lot of isomers of these compounds are produced by plants, making their analysis very difficult and causing many structural misinterpretations. Galactosides and glucosides as mono- or oligosaccharides yield many diastereoisomers, hindering the analysis by mass spectrometry. In order to enable the mass spectrometric distinctions of these isomers, in this work we combine an isopropylidene based chemical derivatization with liquid chromatography with multiple-stage mass spectrometry (LC-MS(n)) analysis. The isomers of flavonol triglycosides, after the reaction, yielded products with different molecular weight, therefore, they were no longer isomers, allowing their identification by MS(1) analysis. However, to the 4 isomers of flavonol diglycosides, only one yielded, after isopropylidenation, a product with different molecular weight. To the other 3 species, the incorporation of 2 isopropylidene groups retained them in the isomeric form. For such species, chromatographic separation and MS(n) detection targeting the lithium adducts of 3,4-O-isopropylidene-galactosyl or 4,6-O-isopropylidene-glucosyl residues (m/z 209.099) provided specific MS profile.


Assuntos
Flavonóis/análise , Glicosídeos/análise , Maytenus/química , Cromatografia Líquida , Galactosídeos/análise , Glucosídeos/análise , Folhas de Planta/química , Estereoisomerismo , Espectrometria de Massas em Tandem/métodos
9.
Carbohydr Polym ; 131: 370-6, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26256196

RESUMO

The mucilage of the jaracatiá fruit (Carica quercifolia (A. St. Hil.) Hieron) was extracted and for physicochemical characterization. The monosaccharide composition showed the presence of Rha, Ara, Xyl, Gal, Glc and GalA, being confirmed by GC-MS, FTIR and NMR. The mucilage was obtained in crude form by lyophilization of the extract and by precipitation, a process that resulted in a partial purification. Although not remarkable, it showed an antioxidant and antimicrobial potential. The thermogravimetric analysis indicated an easy handling at temperatures below 250°C. The natural reactivity of the material indicates for uses such as adsorbent or raw material for membranes.


Assuntos
Carica/química , Mucilagem Vegetal/isolamento & purificação , Mucilagem Vegetal/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Precipitação Química , Testes de Sensibilidade Microbiana , Monossacarídeos/análise , Polissacarídeos/análise , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
10.
Talanta ; 135: 50-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25640125

RESUMO

Leaves of Arctium lappa contain several mono- and dicaffeoylquinic acids, as evaluated by liquid chromatography-mass spectrometry. In order to investigate the protection on gastric mucosa against ulcers, rats were treated with fractions from leaf extract prior to ethanol-induced ulcers. The original fraction obtained as ethanol soluble fraction from hot aqueous extract was able to protect de gastric mucosa, and this effect was retained in the ethyl acetate fraction, obtained from liquid/liquid fractionation. The main compound in this fraction was isolated and chemically characterized by nuclear magnetic resonance and mass spectrometry, assisted by isopropylidene derivatization which gave rise a mass increment of 40 units. Therefore, the underivatized compound that had m/z 515.119 [M-H](-) was shifted to m/z 555.151, being confirmed as 1,3-O-dicaffeoylquinic acid, which presented an ED50 of 57 µg kg(-1) on gastric protection, lesser than the therapeutic concentration of omeprazole (40 mg kg(-1)).


Assuntos
Antiulcerosos , Arctium , Ácido Quínico/análogos & derivados , Úlcera Gástrica/tratamento farmacológico , Animais , Antiulcerosos/química , Antiulcerosos/isolamento & purificação , Antiulcerosos/uso terapêutico , Etanol , Isomerismo , Extratos Vegetais/química , Folhas de Planta , Ácido Quínico/química , Ácido Quínico/isolamento & purificação , Ácido Quínico/uso terapêutico , Ratos Wistar , Úlcera Gástrica/induzido quimicamente
11.
Mar Drugs ; 11(11): 4628-40, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24284427

RESUMO

Total lipids from the Brazilian brown seaweed Sargassum vulgare were extracted with chloroform/methanol 2:1 and 1:2 (v/v) at room temperature. After performing Folch partition of the crude lipid extract, the lipids recovered from the Folch lower layer were fractionated on a silica gel column eluted with chloroform, acetone and methanol. The fraction eluted with methanol, presented a strong orcinol-positive band characteristic of the presence of sulfatides when examined by TLC. This fraction was then purified by two successive silica gel column chromatography giving rise to fractions F4I86 and F4II90 that exhibited strong activity against herpes simplex virus type 1 and 2. The chemical structures present in both fractions were elucidated by ESI-MS and ¹H/¹³C NMR analysis HSQC fingerprints based on their tandem-MS behavior as Sulfoquinovosyldiacylglycerols (SQDGs). The main SQDG present in both fractions and responsible for the anti-herpes activity observed was identified as 1,2-di-O-palmitoyl-3-O-(6-sulfo-α-D-quinovopyranosyl)-glycerol.


Assuntos
Antivirais/química , Glicolipídeos/química , Glicolipídeos/farmacologia , Sargassum/química , Alga Marinha/química , Animais , Antivirais/farmacologia , Brasil , Linhagem Celular , Chlorocebus aethiops , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Lipídeos/química , Lipídeos/farmacologia , Células Vero
12.
Carbohydr Polym ; 94(1): 704-11, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23544593

RESUMO

Native polysaccharide from pineapple gum (PANP) was obtained following alkaline extraction of gum and fractionation with cetylpyridinium chloride. It was characterized as a glucuronoarabinoxylan using NMR, methylation data, controlled Smith degradation, carboxy-reduction, and ESI-MS of oligosaccharides produced on mild acid hydrolysis of PANP. HSPEC-MALLS-RI of carboxy-reduced fraction showed homogeneous profile (Mw 1.943×10(5) g/mol). PANP was composed of Ara, Xyl, Gal, and GlcpA (40:23:7:30 molar ratio). Its main chain presented (1→4)-linked ß-xylan, highly substituted at O-2 and O-3 by side chains of 3-O- and 3,5-di-O-linked α-Araf, 2-O- and 4-O-linked α-GlcpA, and nonreducing end-units of α-Araf, ß-Arap, ß-Galp, and α-GlcpA. ESI-MS of a mixture of oligosaccharides formed on the mild acid hydrolysis of PANP was consistent with repetitive structures of α-GlcpA O-3 linked at ß-Xylp units, whereas in others glucuronoarabinoxylan-type gum exudates, α-GlcpA units had been previously found to be linked at O-2.


Assuntos
Ananas/química , Gomas Vegetais/química , Xilanos/química , Configuração de Carboidratos , Sequência de Carboidratos , Cetilpiridínio/química , Precipitação Fracionada , Hidrólise , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular , Peso Molecular , Oxirredução , Gomas Vegetais/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Xilanos/isolamento & purificação
13.
Carbohydr Polym ; 92(2): 1776-82, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23399219

RESUMO

The present study evaluated the anti-inflammatory activity of a polysaccharide from maté, using a clinically relevant model of sepsis induced by cecal ligation and puncture (CLP). A polysaccharide from maté (SPI) was obtained from aqueous extraction followed by fractionation, being identified as a rhamnogalacturonan with a main chain of →4)-6-OMe-α-D-GalpA-(1→ groups, interrupted by α-L-Rhap units, substituted by a type I arabinogalactan. SPI was tested against induced-polymicrobial sepsis, at doses of 3, 7 and 10 mg/kg. Via oral administration, SPI prevented the late mortality of infected mice by a rate of 60% at 10 mg/kg, in comparison with untreated mice Dexamethasone, used as positive control, was slightly less effective, with an overall survival rate of 16.7% of mice at the end of the observation period. SPI also affected neutrophil influx, avoiding its accumulation in lungs, and significantly decreased tissue expression of iNOS and COX-2. In this context, maté is a potential nutraceutical, and its polysaccharide a promising adjuvant for sepsis treatment, being consumed as tea-like beverages with no related adverse effects.


Assuntos
Ilex paraguariensis/química , Pectinas/farmacologia , Sepse/tratamento farmacológico , Animais , Movimento Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ligadura/efeitos adversos , Masculino , Metilação , Camundongos , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Pectinas/química , Pectinas/isolamento & purificação , Pectinas/uso terapêutico , Punções/efeitos adversos , Sepse/enzimologia , Sepse/etiologia , Sepse/imunologia , Água/química
14.
Phytochemistry ; 85: 137-42, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23014505

RESUMO

The plant Acmella oleracea (L.) R.K.Jansen (Asteraceae), locally known as jambu, is widely used in Legal Amazon in local dishes and in folk medicine. A polysaccharide (SC) was isolated from this plant, following aqueous extraction, which contained uronic acid, galactose, arabinose, rhamnose, and glucose in a 15:2:1:1:0.5 molar ratio and had a M(w) 226,000 g/mol. Methylation analysis and NMR spectroscopy indicated that SC is a rhamnogalacturonan composed of a long chain of →4)-6-OMe-α-D-GalpA-(1→, interspersed with some α-L-Rhap residues, partly substituted by side-chains of type II arabinogalactans. SC significantly inhibited ethanol-induced gastric ulcers in rats with an ED50 of 1.5 mg/kg, indicating that SC acts as gastroprotective agent.


Assuntos
Antiulcerosos/química , Antiulcerosos/uso terapêutico , Asteraceae/química , Úlcera Gástrica/tratamento farmacológico , Animais , Cromatografia por Troca Iônica , Feminino , Espectroscopia de Ressonância Magnética , Pectinas , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente
15.
BMC Microbiol ; 12: 252, 2012 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-23131170

RESUMO

BACKGROUND: Bacillus sp. H2O-1, isolated from the connate water of a Brazilian reservoir, produces an antimicrobial substance (denoted as AMS H2O-1) that is active against sulfate reducing bacteria, which are the major bacterial group responsible for biogenic souring and biocorrosion in petroleum reservoirs. Thus, the use of AMS H2O-1 for sulfate reducing bacteria control in the petroleum industry is a promising alternative to chemical biocides. However, prior to the large-scale production of AMS H2O-1 for industrial applications, its chemical structure must be elucidated. This study also analyzed the changes in the wetting properties of different surfaces conditioned with AMS H2O-1 and demonstrated the effect of AMS H2O-1 on sulfate reducing bacteria cells. RESULTS: A lipopeptide mixture from AMS H2O-1 was partially purified on a silica gel column and identified via mass spectrometry (ESI-MS). It comprises four major components that range in size from 1007 to 1049 Da. The lipid moiety contains linear and branched ß-hydroxy fatty acids that range in length from C13 to C16. The peptide moiety contains seven amino acids identified as Glu-Leu-Leu-Val-Asp-Leu-Leu.Transmission electron microscopy revealed cell membrane alteration of sulfate reducing bacteria after AMS H2O-1 treatment at the minimum inhibitory concentration (5 µg/ml). Cytoplasmic electron dense inclusions were observed in treated cells but not in untreated cells. AMS H2O-1 enhanced the osmosis of sulfate reducing bacteria cells and caused the leakage of the intracellular contents. In addition, contact angle measurements indicated that different surfaces conditioned by AMS H2O-1 were less hydrophobic and more electron-donor than untreated surfaces. CONCLUSION: AMS H2O-1 is a mixture of four surfactin-like homologues, and its biocidal activity and surfactant properties suggest that this compound may be a good candidate for sulfate reducing bacteria control. Thus, it is a potential alternative to the chemical biocides or surface coating agents currently used to prevent SRB growth in petroleum industries.


Assuntos
Antibacterianos/metabolismo , Bacillus/genética , Bacillus/metabolismo , Lipopeptídeos/genética , Lipopeptídeos/metabolismo , Bactérias Redutoras de Enxofre/efeitos dos fármacos , Tensoativos/metabolismo , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bacillus/isolamento & purificação , Brasil , Membrana Celular/ultraestrutura , Cromatografia , DNA Bacteriano/química , DNA Bacteriano/genética , Lipopeptídeos/química , Lipopeptídeos/isolamento & purificação , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Peso Molecular , Análise de Sequência de DNA , Bactérias Redutoras de Enxofre/ultraestrutura , Tensoativos/química , Tensoativos/isolamento & purificação , Microbiologia da Água
16.
Mar Drugs ; 10(4): 918-931, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22690151

RESUMO

Glycolipids were extracted from the red alga Osmundaria obtusiloba from Southeastern Brazilian coast. The acetone insoluble material was extracted with chloroform/methanol and the lipids, enriched in glycolipids, were fractionated on a silica gel column eluted with chloroform, acetone and then methanol. Three major orcinol-positive bands were found in the acetone and methanol fractions, being detected by thin layer chromatography. The structures of the corresponding glycolipids were elucidated by ESI-MS and (1)H/(13)C NMR analysis, on the basis of their tandem-MS behavior and HSQC, TOCSY fingerprints. For the first time, the structure of sulfoquinovosyldiacylglycerol from the red alga Osmundaria obtusiloba was characterized. This molecule exhibited potent antiviral activity against HSV-1 and HSV-2 with EC(50) values of 42 µg/mL to HSV-1 and 12 µg/mL to HSV-2, respectively. Two other glycolipids, mono- and digalactosyldiacylglycerol, were also found in the alga, being characterized by ESI-MS/MS. The structural elucidation of algae glycolipids is a first step for a better understanding of the relation between these structures and their biological activities.


Assuntos
Antivirais/química , Antivirais/farmacologia , Glicolipídeos/química , Glicolipídeos/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Rodófitas/química , Animais , Antivirais/isolamento & purificação , Brasil , Galactolipídeos/química , Galactolipídeos/isolamento & purificação , Galactolipídeos/farmacologia , Glicolipídeos/isolamento & purificação , Lipídeos/química , Lipídeos/isolamento & purificação , Lipídeos/farmacologia , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Células Vero
17.
J Chromatogr A ; 1222: 29-37, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-22204932

RESUMO

Green and black teas (Camellia sinensis) contain compounds ranging from simple phenolics to complex glycosides, many of which have well-recognized health benefits. Here, we describe two methodologies aiming to achieve a comprehensive analysis of hydro-alcoholic extracts of C. sinensis. In the first step, the extracts were partitioned in water, n-butanol, ethyl acetate and chloroform to separate the compounds according to their polarity, yielding less complex samples to be analyzed by ultra high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS). Additionally, a comprehensive two dimensional liquid chromatography (2D-LC) technique, employing size exclusion chromatography (SEC) × reversed phase (BEH-C18) was developed. The following compounds were identified on the basis of retention time, UV-spectra and MS fragmentation patterns: catechins, theaflavins and their gallate derivatives; kaempferol, quercetin and myricetin mono-, di-, tri- and tetraglycosides; esters of quinic acid and gallic or hydroxycinnamic acids; purine alkaloids, such as caffeine and theobromine and many lipids. Additionally, there were many novel compounds that were previously undescribed, such as saponin isomers and gallic acid esters of four glycosides of myricetin, quercetin and kaempferol.


Assuntos
Camellia sinensis/química , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Extração Líquido-Líquido/métodos , Chá/química , Cromatografia de Fase Reversa/métodos , Cinamatos/análise , Flavonoides/análise , Ácido Gálico/análise , Espectrometria de Massas , Saponinas/análise
18.
Front Microbiol ; 2: 239, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22164155

RESUMO

Of the ceramide monohexosides (CMHs), gluco- and galactosyl-ceramides are the main neutral glycosphingolipids expressed in fungal cells. Their structural determination is greatly dependent on the use of mass spectrometric techniques, including fast atom bombardment-mass spectrometry, electrospray ionization, and energy collision-induced dissociation mass spectrometry. Nuclear magnetic resonance has also been used successfully. Such a combination of techniques, combined with classical analytical separation, such as high-performance thin layer chromatography and column chromatography, has led to the structural elucidation of a great number of fungal CMHs. The structure of fungal CMH is conserved among fungal species and consists of a glucose or galactose residue attached to a ceramide moiety containing 9-methyl-4,8-sphingadienine with an amidic linkage to hydroxylated fatty acids, most commonly having 16 or 18 carbon atoms and unsaturation between C-3 and C-4. Along with their unique structural characteristics, fungal CMHs have a peculiar subcellular distribution and striking biological properties. Fungal cerebrosides were also characterized as antigenic molecules directly or indirectly involved in cell growth or differentiation in Schizophyllum commune, Cryptococcus neoformans, Pseudallescheria boydii, Candida albicans, Aspergillus nidulans, Aspergillus fumigatus, and Colletotrichum gloeosporioides. Besides classical techniques for cerebroside (CMH) analysis, we now describe new approaches, combining conventional thin layer chromatography and mass spectrometry, as well as emerging technologies for subcellular localization and distribution of glycosphingolipids by secondary ion mass spectrometry and imaging matrix-assisted laser desorption ionization time-of-flight.

19.
J Chromatogr A ; 1218(41): 7307-15, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-21899851

RESUMO

Ilex paraguariensis (maté) is an important plant from southern Brazil, Paraguay, Uruguay and Argentina, where its leaves are widely used in hot or cold beverages. We now present a comprehensive ULPC-PDA-MS analysis of the compounds found in its leaves. The analysis was rapid, less than 13 min and many compounds were identified, among these, the chlorogenic acid series, and other quinic acid derivatives, xanthines, and several saponins, many of which have not been previously described, including many isomers. The isomerism could occur in the aglycone moiety, namely ursolic or oleanolic acid, or in the carbohydrate moiety. Additionally, many acetylated saponins were detected. The structure of known and novel saponins was determined using per-O-methylation with ESI-MS analysis, as well as with GC-MS of their partially O-methylated alditol acetate (PMAA) derivatives, along with ESI-MS analysis of the O-isopropylidene (IPP) derivatives provided fundamental information on interglycosidic linkages, avoiding the purification steps.


Assuntos
Ilex paraguariensis/química , Extratos Vegetais/química , Saponinas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Ácido Clorogênico/química , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Isomerismo , Folhas de Planta/química , Ácido Quínico/química , Saponinas/química , Xantinas/química
20.
PLoS One ; 6(1): e15970, 2011 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-21267460

RESUMO

The year 2007 was marked by widespread adverse clinical responses to heparin use, leading to a global recall of potentially affected heparin batches in 2008. Several analytical methods have since been developed to detect impurities in heparin preparations; however, many are costly and dependent on instrumentation with only limited accessibility. A method based on a simple UV-scanning assay, combined with principal component analysis (PCA), was developed to detect impurities, such as glycosaminoglycans, other complex polysaccharides and aromatic compounds, in heparin preparations. Results were confirmed by NMR spectroscopy. This approach provides an additional, sensitive tool to determine heparin purity and safety, even when NMR spectroscopy failed, requiring only standard laboratory equipment and computing facilities.


Assuntos
Heparina/normas , Espectroscopia de Ressonância Magnética , Análise de Componente Principal , Espectrofotometria Ultravioleta , Contaminação de Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Espectroscopia de Ressonância Magnética/métodos , Métodos , Padrões de Referência , Espectrofotometria Ultravioleta/métodos
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