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1.
Int J Mol Sci ; 22(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34768966

RESUMO

A daily consumption of cranberry juice (CJ) is linked to many beneficial health effects due to its richness in polyphenols but could also awake some intestinal discomforts due to its organic acid content and possibly lead to intestinal inflammation. Additionally, the impact of such a juice on the gut microbiota is still unknown. Thus, this study aimed to determine the impacts of a daily consumption of CJ and its successive deacidification on the intestinal inflammation and on the gut microbiota in mice. Four deacidified CJs (DCJs) (deacidification rates of 0, 40, 60, and 80%) were produced by electrodialysis with bipolar membrane (EDBM) and administered to C57BL/6J mice for four weeks, while the diet (CHOW) and the water were ad libitum. Different parameters were measured to determine intestinal inflammation when the gut microbiota was profiled. Treatment with a 0% DCJ did not induce intestinal inflammation but increased the gut microbiota diversity and induced a modulation of its functions in comparison with control (water). The effect of the removal of the organic acid content of CJ on the decrease of intestinal inflammation could not be observed. However, deacidification by EDBM of CJ induced an additional increase, in comparison with a 0% DCJ, in the Lachnospiraceae family which have beneficial effects and functions associated with protection of the intestine: the lower the organic acid content, the more bacteria of the Lachnospiraceae family and functions having a positive impact on the gut microbiota.


Assuntos
Ácidos/efeitos adversos , Sucos de Frutas e Vegetais/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Vaccinium macrocarpon/efeitos adversos , Ácidos/química , Ácidos/isolamento & purificação , Fenômenos Fisiológicos da Nutrição Animal , Animais , Biodiversidade , Diálise/métodos , Feminino , Sucos de Frutas e Vegetais/análise , Concentração de Íons de Hidrogênio , Inflamação/etiologia , Inflamação/patologia , Intestinos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Vaccinium macrocarpon/química
2.
Anal Bioanal Chem ; 412(27): 7491-7503, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32970177

RESUMO

Organic acids play a key role in central metabolic functions of organisms, are crucial for understanding regulatory processes and are ubiquitous inside the cell. Therefore, quantification of these compounds provides a valuable approach for studying dynamics of metabolic processes, in particular when the organism faces changing environmental conditions. However, the extraction and analysis of organic acids can be challenging and validated methods available in this field are limited. In this study, we developed a method for the extraction and quantification of organic acids from microbial samples based on solid-phase extraction on a strong anionic exchange cartridge and gas chromatographic-mass spectrometric analysis. Full method validation was conducted to determine quality parameters of the new method. Recoveries for 12 of the 15 aromatic and aliphatic acids were between 100 and 111% and detection limits between 3 and 272 ng/mL. The ranges for the regression coefficients and process standard deviations for these compound classes were 0.9874-0.9994 and 0.04-0.69 µg/mL, respectively. Limitations were encountered when targeting aliphatic acids with hydroxy, oxo or enol ester functions. Finally, we demonstrated the applicability of the method on cell extracts of the bacterium Escherichia coli and the dinoflagellate Prorocentrum minimum. Graphical abstract.


Assuntos
Ácidos/análise , Dinoflagellida/química , Escherichia coli/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extração em Fase Sólida/métodos , Ácidos/isolamento & purificação , Limite de Detecção , Compostos Orgânicos/análise , Compostos Orgânicos/isolamento & purificação
3.
J Chromatogr A ; 1619: 460914, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32008820

RESUMO

Recently, ion chromatography coupled with mass spectrometry has been used for the determination of anionic metabolites. However, connection with a mass spectrometer in this method is not straightforward because backpressure produced by the addition of a make-up solution often affects the peak resolutions of the target metabolites. To overcome this problem, we developed a capillary ion chromatography-mass spectrometry method utilizing a double coaxial electrospray ionization sprayer. This method was not affected by backpressure and the number of theoretical plates was about three times that of a conventional sprayer. Under optimized conditions, 44 anionic metabolites, including organic acids, sugar phosphates, nucleotides, and cofactors, were successfully separated and selectively detected with a Q Exactive mass spectrometer. The calibration curves of the tested metabolites showed excellent linearity within the range of 1-100,000 nmol/L and the correlation coefficient was greater than 0.991. The detection limits for these metabolites were between 1 and 500 nmol/L (0.4 and 200 fmol). The developed method was applied to the quantitation of anionic metabolites in cultured cancer cell samples with tumor necrosis factor (TNF)-α stimulation. This allowed for the successful determination of 105 metabolites. The levels of tricarboxylic acid cycle intermediates changed significantly after TNF-α stimulation. These results demonstrate that the developed method is a promising new tool for comprehensive analysis of anionic metabolites.


Assuntos
Espectrometria de Massas por Ionização por Electrospray/métodos , Ácidos/análise , Ácidos/isolamento & purificação , Ânions/química , Calibragem , Cromatografia/métodos , Humanos , Limite de Detecção , Neoplasias/metabolismo , Nucleotídeos/análise , Nucleotídeos/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray/normas , Fator de Necrose Tumoral alfa/farmacologia
4.
Cardiovasc Ther ; 2019: 8496409, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772618

RESUMO

BACKGROUND: Cuban sugarcane wax acids (SCWA) and policosanol (PCO) are mixtures of higher aliphatic acids and alcohols, respectively, purified from sugarcane wax with different chief components. Although it has been known that they have antioxidant and anti-inflammatory activities, physiological properties on molecular mechanism of SCWA have been less studied than PCO. METHODS: In this study, we compared antiatherogenic activities of SCWA and PCO via encapsulation with reconstituted high-density lipoproteins (rHDL). RESULTS: After reconstitution, SCWA-rHDL showed smaller particle size than PCO-rHDL with increase of content. PCO-rHDL or SCWA-rHDL showed distinct inhibition of glycation with similar extent in the presence of fructose. PCO-rHDL or SCWA-rHDL showed strong antioxidant activity against cupric ion-mediated oxidation of low-density lipoproteins (LDL), and inhibition of oxLDL uptake into macrophages. Although PCO-rHDL showed 1.2-fold stronger inhibition against cholesteryl ester transfer protein (CETP) activity than SCWA-rHDL, SCWA-rHDL enhanced 15% more brain cell (BV-2) growth and 23% more regeneration of tail fin in zebrafish. CONCLUSION: PCO and SCWA both enhance the beneficial functions of HDL to maximize its antioxidant, antiglycation, and antiatherosclerotic activities and the inhibition of CETP. These enhancements of HDL functionality by PCO and SCWA could exert antiaging and rejuvenation activity.


Assuntos
Ácidos/farmacologia , Anticolesterolemiantes/farmacologia , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Álcoois Graxos/farmacologia , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saccharum/química , Ceras/química , Ácidos/isolamento & purificação , Nadadeiras de Animais/efeitos dos fármacos , Nadadeiras de Animais/crescimento & desenvolvimento , Animais , Anticolesterolemiantes/isolamento & purificação , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Álcoois Graxos/isolamento & purificação , Humanos , Macrófagos/metabolismo , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Oxirredução , Extratos Vegetais/isolamento & purificação , Regeneração , Células THP-1 , Adulto Jovem , Peixe-Zebra/crescimento & desenvolvimento
5.
Fitoterapia ; 131: 209-214, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30385401

RESUMO

In this study, a resin glycoside fraction with cytotoxic activity was isolated from the alcoholic extract of C. arvensis whole plants. To describe the chemical feature of the resin glycosides, the fraction was alkaline hydrolyzed and four novel glycosidic acids, named arvensic acids A-D (1-4), were isolated. Their structures were thoroughly elucidated on the basis of spectroscopic data and chemical evidences. They all possess a same heptasacharride core, consisting of one D-fucose, two L-rhamnose and four d-glucose units. The difference among these glycosidic acids was placed on the aglycone, which is 12S-hydroxypentadecanoic acid for 1, 12S-hydroxyhexadecanoic acid for 2, 3S,12S-dihydroxypentadecanoic acid for 3, and 3S,12S- dihydroxyhexadecanoic acid for 4. These aglycones are rarely found in the structures of resin glycosides and are firstly identified in the genus Convolvulus.


Assuntos
Ácidos/química , Convolvulus/química , Glicosídeos/química , Resinas Vegetais/química , Células A549 , Ácidos/isolamento & purificação , China , Glicosídeos/isolamento & purificação , Células HeLa , Humanos , Hidrólise , Células MCF-7 , Compostos Fitoquímicos/isolamento & purificação
6.
Fitoterapia ; 124: 86-91, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29074225

RESUMO

Four new phenylisotertronic acids (1a/1b, 2a, and 3a) were isolated from a TCM endophytic fungal strain Phyllosticta sp. J13-2-12Y obtained from the leaves of Acorus tatarinowii, along with two known ones (2b and 3b). Compounds 1-3 all existed as mixtures of enantiomers, and their corresponding optically pure enantiomers were successfully isolated by chiral HPLC. The structures of isolated compounds were determined by comprehensive spectroscopic analyses and X-ray diffraction. Their absolute configurations were determined by ECD experiments and quantum chemical calculations. In addition, the antimicrobial activities and the cytotoxicities of these three pairs of optically pure enantiomers (1a/1b, 2a/2b, and 3a/3b) had been evaluated.


Assuntos
Ácidos/isolamento & purificação , Acorus/microbiologia , Ascomicetos/química , Furanos/isolamento & purificação , Antifúngicos/isolamento & purificação , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Humanos , Estrutura Molecular , Estereoisomerismo , Difração de Raios X
7.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1017-1018: 211-220, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26990736

RESUMO

A simple and effective multi-residue method was developed and validated for the analysis of 26 organochlorine pesticide residues in Alpinia oxyphylla by a gas chromatography with an electron capture detector (GC-ECD). The target pesticides were extracted by sonication and cleaned up with florisil solid phase extraction and sulphuric acid. Some crucial parameters, including extraction solvent and time, sorbent type, elute solvent and concentration of sulphuric acid were optimized to improve the performance of sample preparation procedure. The optimized method gave high sensitivity with detection limit ranging from 0.1 to 2.0µg/kg. Matrix-matched calibration was employed for the quantification, and a wide linear range (from 1.0 to 1000µg/kg) with r(2) values ranging from 0.9971 to 0.9998 was obtained. For the majority of the tested pesticides, the average recoveries were in acceptable range (between 70% and 110%) with relative standard deviation values below 15.0%. Matrix effect was evaluated for target compounds through the study of ratio of peak area obtained in the solvent and blank matrix. The proposed method was applied to simultaneously analyze 26 pesticides in 55 batches of Alpinia oxyphylla samples. 3 samples were found to be positive with four pesticides (α-BHC, quintozene, trans-chlordane and op'-DDD), which were confirmed by gas chromatography-mass spectrometry (GC-MS) in selective ion monitoring (SIM) mode.


Assuntos
Ácidos/isolamento & purificação , Alpinia/química , Cromatografia Gasosa/métodos , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Microextração em Fase Sólida/métodos
9.
J Environ Sci Eng ; 55(2): 253-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25464702

RESUMO

Pickling is the process of removal of oxide layer and rust formed on metal surface. It also removes sand and corrosion products from the surface of metal. Acids such as sulfuric acid, hydrochloric acid are used for pickling. Hydrofluoric acid-Nitric acid mixture is used for stainless steel pickling. Pickling solutions are spent when acid concentration in pickling solutions decreases by 75-85%, which also has metal content up to 150-250 g/ dm3. Spent pickling liquor (SPL) should be dumped because the efficiency of pickling decreases with increasing content of dissolved metal in the bath. The SPL content depends on the plant of origin and the pickling method applied there. SPL from steel pickling in hot-dip galvanizing plants contains zinc(II), iron, traces of lead, chromium. and other heavy metals (max. 500 mg/dm3) and hydrochloric acid. Zinc(II) passes tothe spent solution after dissolution of this metal from zinc(II)-covered racks, chains and baskets used for transportation of galvanized elements. Unevenly covered zinc layers are usually removed in another pickling bath. Due to this, zinc(II) concentration increases even up to 110 g/dm3, while iron content may reach or exceed even 80 g/dm3 in the same solution. This review presents an overview on different aspects of generation and treatment of SPL with recourse to recovery of acid for recycling. Different processes are described in this review and higher weightage is given to membrane processes.


Assuntos
Ácidos/isolamento & purificação , Resíduos Industriais , Metalurgia/métodos , Gerenciamento de Resíduos/métodos , Aço
10.
Anal Bioanal Chem ; 401(9): 2965-76, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21935597

RESUMO

Two solid-phase microextraction (SPME) sorbent coatings based on polymeric ionic liquids (PILs) have been utilized for the analysis of complex coffee aroma samples. The PIL-based SPME coatings examined, namely, poly(1-(4-vinylbenzyl)-3-hexadecylimidazolium bis[(trifluoromethyl)sulfonyl]imide) [poly(VBHDIm(+) NTf(2)(-))], with ~14-µm thickness, and poly(1-vinyl-3-hexylimidazolium chloride) [poly(ViHIm(+)Cl(-))], with ~8-µm thickness, were employed for the headspace determination of up to 49 analytes from four different coffee beans: two French roast coffees of different brands, Sumatra coffee, and decaffeinated Sumatra coffee. The analysis was conducted using gas chromatography coupled to mass spectrometry. For comparative purposes, the commercial polyacrylate (PA, 85-µm film thickness) SPME coating was utilized under the same extraction conditions. The three SPME coatings tested behaved quite differently as a function of the families of compounds extracted. Thus, the poly(VBHDIm(+) NTf(2)(-) ) coating was extremely selective for aldehydes while also exhibiting good extraction efficiencies for acids. The poly-(ViHIm(+) Cl(-)) coating exhibited superior performance for aromatic alcohols, and the PA coating worked better for heterocyclic aromatics. Both PIL-based SPME sorbent coatings demonstrated exceptional selectivity and extraction efficiency when dealing with complex coffee aromas in spite of their small film thicknesses.


Assuntos
Café/química , Tecnologia de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Líquidos Iônicos/química , Microextração em Fase Sólida/métodos , Ácidos/análise , Ácidos/isolamento & purificação , Resinas Acrílicas/química , Álcoois/análise , Álcoois/isolamento & purificação , Aldeídos/análise , Aldeídos/isolamento & purificação , Imidazóis/química , Imidas/química , Polímeros/química , Sensibilidade e Especificidade
11.
J Hazard Mater ; 171(1-3): 61-75, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19632040

RESUMO

Every metal and metallurgical industry is associated with the generation of waste, which may be a solid, liquid or gaseous in nature. Their impacts on the ecological bodies are noticeable due to their complex and hazardous nature affecting the living and non-living environment which is an alarming issue to the environmentalist. The increasingly stringent regulations regarding the discharge of acid and metal into the environment, and the increasing stress upon the recycling/reuse of these effluents after proper treatment have focused the interest of the research community on the development of new approaches for the recovery of acid and metals from industrial wastes. This paper is a critical review on the acidic waste streams generated from steel and electroplating industries particularly from waste pickle liquor and spent bleed streams. Various aspects on the generation of these streams and the methods used for their treatment either for the recovery of acid for reuse or disposal are being dealt with. Major stress is laid upon the hydrometallurgical methods such as solvent extraction.


Assuntos
Ácidos/isolamento & purificação , Galvanoplastia/instrumentação , Galvanoplastia/métodos , Resíduos Industriais , Poluentes Químicos da Água/isolamento & purificação , Ácidos/química , Cromatografia por Troca Iônica/métodos , Cobre/química , Eletrólise , Ácido Clorídrico/análise , Hidrólise , Metais/química , Oxirredução , Solventes/química , Ácidos Sulfúricos/análise , Purificação da Água , Zinco/química
12.
Water Res ; 43(8): 2302-16, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19297003

RESUMO

A passively operated multi-stage bioremediation system utilizing composted agricultural waste products and an artificial wetland system was found to be effective for purification of acidic, iron- and sulfate-rich waste water derived from titanium mineral processing. The main microbial players involved in the remediation system processes and the dynamics were investigated; mineral processing waste water-filled sludge dams possessed stable microbial communities that included Acidithiobacillus, Desulfurella, and acidophilic, anaerobic fermenters of the order Bacteroidales. These groups were enriched in a subsequent potato waste-based iron mobilization pre-treatment stage. Within downstream reduction treatment stages ("reduction cells"), compost/straw decomposition and associated sulfur/sulfate and iron reduction were carried out by a complex mix of aerobic and anaerobic bacteria. The efficaciousness of the system without replacement of the compost was found to steadily decline following 2 years of operation and corresponded with the reduction cell communities becoming simultaneously more diverse and homogenous. Microcosm-based experiments demonstrated that operational declines were due to unsustained supply of suitable labile carbon sources combined with spatial heterogeneity within the layered design of the reduction stage of the system resulting in inadequate redox conditions. Temperature was not found to be a critical performance factor in the range of 10-25 degrees C. Application of a combined emulsified oil/molasses amendment was found to be highly effective in promoting a microbial community capable of remediating waste water with high iron and sulfate levels. Acidophilic members of the order Bacteroidales were found to be critical in the investigated remediation system, providing organic donors for subsequent metal and sulfur transformations and could have a broader ecological significance than previously suspected.


Assuntos
Ácidos/isolamento & purificação , Resíduos Industriais , Ferro/isolamento & purificação , Solo , Sulfatos/isolamento & purificação , Eliminação de Resíduos Líquidos , Purificação da Água , Bactérias/genética , Biodegradação Ambiental , Biodiversidade , Biblioteca Gênica , Geografia , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Esgotos , Fatores de Tempo , Titânio
13.
Environ Sci Technol ; 40(10): 3409-15, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16749714

RESUMO

Headspace of batch minireactors was intermittently vented and gas flushed with N2 in order to enhance H2 production (PH) by anaerobic consortia degrading organic solid wastes. Type of inocula (meso and thermophilic), induction treatment (heat-shock pretreatment, HSP, and acetylene, Ac), and incubation temperature (37 and 55 degrees C) were studied by means of a factorial design. On average, it was found that mesophilic incubation had the most significant positive effect on PH followed by treatment with Ac, although the units with the best performance (high values of PH, initial hydrogen production rate, and short lag time) were those HSP-induced units incubated at 37 degrees C (type of inocula was not significant). In this way, after 720 h of incubation PH was inhibited in those units by H2 partial pressure (pH2) of 0.54 atm. Venting and gas flushing with N2 was efficient to eliminate that inhibition achieving additional hydrogen generation in subsequent incubation cycles although smaller than the first one. Thus, four cycles of PH were obtained from the same substrate with neither addition of inocula nor application of induction treatment obtaining an increment of 100% in the generated H2. In those subsequent cycles there was a positive correlation between PH and organic acids/solvent ratio; maximum values were found in the first cycle. Solventogenesis could be clearly distinguished in third and fourth production cycles, probably due to a metabolic shift originated by high organic acid concentrations.


Assuntos
Reatores Biológicos , Hidrogênio/metabolismo , Resíduos Industriais , Nitrogênio/química , Eliminação de Resíduos/métodos , Ácidos/isolamento & purificação , Ácidos/metabolismo , Anaerobiose , Biomassa , Hidrogênio/química , Concentração de Íons de Hidrogênio , Compostos Orgânicos/isolamento & purificação , Compostos Orgânicos/metabolismo , Temperatura , Eliminação de Resíduos Líquidos
16.
Mutat Res ; 169(3): 129-39, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3951466

RESUMO

Cigarette smoke condensate is known to enhance the frequency of sister-chromatid exchanges (SCE) in human lymphocytes in vitro and some of the activity has been found in the most volatile part of the particulate phase, the semivolatile fraction. In this study we have investigated the chemical composition and the SCE-inducing activity of the weakly acidic, semivolatile fraction of a cigarette smoke condensate. A number of individual weakly acidic compounds were also tested for their SCE-inducing effects. The weakly acidic fraction was separated by preparative gel chromatography into 11 subfractions (F1-F11). The chemical composition was determined by gas chromatography and gas chromatography-mass spectrometry. Measurements of the effects on SCE in human lymphocytes were used to evaluate the genotoxic effects. All fractions except F11 induced SCE in a dose-dependent way. The most active fraction was F4 which contained mainly alkyl-2-hydroxy-2-cyclopenten-1-ones. The individual compounds to be tested for induction of SCE were selected on the basis of their abundance in the weakly acidic subfractions and on the basis of their occurrence in the environment. Of 23 tested compounds, most of which were alkylphenols, 7 induced SCE, i.e., catechol, 2-(1-propenyl)phenol, cyclotene, maltol, isoeugenol, 2-methoxyphenol (guaiacol) and vanillin. Many of these are important flavor components that occur not only in tobacco and tobacco smoke but also in food, candies, beverages and perfumes.


Assuntos
Nicotiana/análise , Plantas Tóxicas , Troca de Cromátide Irmã/efeitos dos fármacos , Fumaça/análise , Ácidos/isolamento & purificação , Ácidos/farmacologia , Benzaldeídos/farmacologia , Aromatizantes/farmacologia , Linfócitos/efeitos dos fármacos , Linfócitos/ultraestrutura , Fenóis/isolamento & purificação , Fenóis/farmacologia , Relação Estrutura-Atividade
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