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1.
Molecules ; 27(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209145

RESUMO

Balsamic vinegar is one of the best known and most popular types of vinegar, and it is a rich source of polyphenolic compounds. The quality of balsamic vinegar as well as the content of phenolic substances vary depending on the production method. In the present work, we have developed a method for comprehensive characterization of the content of phenolic compounds in balsamic vinegars based on the combination of gas chromatography (GC) and high-performance liquid chromatography (HPLC) coupled with mass spectrometric detection in single mode (MS) and tandem mode (MS/MS). In total, 14 samples of different types of balsamic vinegar were analyzed without difficulty in sample preparation. The separation conditions and detection parameters of HPLC-MS/MS were optimized and used for the determination of 29 phenolic compounds and 6 phenolic acids. The profile of phenolic compounds was completed by semi-quantitative analysis of volatile organic compounds using GC-MS after optimized headspace solid-phase microextraction. Gallic acid, protocatechuic acid, caffeic acid, and p-coumaric acid have been identified as the major phenolic compounds in balsamic vinegars.


Assuntos
Ácido Acético/análise , Ácido Acético/química , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem , Ácido Acético/isolamento & purificação , Fracionamento Químico , Fenóis/análise
2.
Molecules ; 25(18)2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32967253

RESUMO

Most of the current commercial production of glacial acetic acid (GAA) is by petrochemical routes, primarily methanol carbonylation. GAA is an intermediate in the production of plastics, textiles, dyes, and paints. GAA production from biomass might be an economically viable and sustainable alternative to petroleum-derived routes. Separation of acetic acid from water is a major expense and requires considerable energy. This study evaluates and compares the technical and economic feasibility of GAA production via bioconversion using either ethyl acetate or alamine in diisobutylkerosene (DIBK) as organic solvents for purification. Models of a GAA biorefinery with a production of 120,650 tons/year were simulated in Aspen software. This biorefinery follows the path of pretreatment, enzymatic hydrolysis, acetogen fermentation, and acid purification. Estimated capital costs for different scenarios ranged from USD 186 to 245 million. Recovery of GGA using alamine/DIBK was a more economical process and consumed 64% less energy, due to lower steam demand in the recovery distillation columns. The estimated average minimum selling prices of GGA were USD 756 and 877/ton for alamine/DIBK and ethyl acetate scenarios, respectively. This work establishes a feasible and sustainable approach to produce GGA from poplar biomass via fermentation.


Assuntos
Ácido Acético/metabolismo , Biomassa , Custos e Análise de Custo , Populus/metabolismo , Ácido Acético/isolamento & purificação , Biotransformação
3.
Int J Mol Sci ; 20(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408956

RESUMO

This paper first reports on the selective separation of volatile fatty acids (VFAs) (acetic and hexanoic acids) using polymer inclusion membranes (PIMs) containing quaternary ammonium and phosphonium ionic liquids (ILs) as the carrier. The affecting parameters such as IL content, VFA concentration, and the initial pH of the feed solution as well as the type and concentration of the stripping solution were investigated. PIMs performed a much higher selective separation performance toward hexanoic acid. The optimal PIM composed of 60 wt% quaternary ammonium IL with the permeability coefficients for acetic and hexanoic acid of 0.72 and 4.38 µm s-1, respectively, was determined. The purity of hexanoic acid obtained in the stripping solution increased with an increase in the VFA concentration of the feed solution and decreasing HCl concentration of the stripping solution. The use of Na2CO3 as the stripping solution and the involvement of the electrodialysis process could dramatically enhance the transport efficiency of both VFAs, but the separation efficiency decreased sharply. Furthermore, a coordinating mechanism containing hydrogen bonding and ion exchange for VFA transport was demonstrated. The highest purity of hexanoic acid (89.3%) in the stripping solution demonstrated that this PIM technology has good prospects for the separation and recovery of VFAs from aqueous solutions.


Assuntos
Ácido Acético/isolamento & purificação , Caproatos/isolamento & purificação , Líquidos Iônicos/química , Membranas Artificiais , Polímeros/química , Ácidos Graxos Voláteis/isolamento & purificação , Modelos Moleculares , Permeabilidade , Compostos de Amônio Quaternário/química
4.
Appl Microbiol Biotechnol ; 102(6): 2535-2541, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29430583

RESUMO

Aerobic Acetobacter pasteurianus is one of the most widely used bacterial species for acetic acid and vinegar production. The acetic acid condition is the primary challenge to the industrial application of A. pasteurianus. Thus, numerous endeavors, including strain improvement and process control, have been performed to improve the product formation and acetic acid tolerance of A. pasteurianus. The metabolic features of A. pasteurianus have been gradually elucidated through omic techniques, such as genomics and proteomics. In this mini review, we summarized bioprocess engineering methods that improved product formation of A. pasteurianus by exploiting its metabolic features. Moreover, given that A. pasteurianus is an important functional microorganism in traditional vinegar production, we discuss its metabolism when cocultured with other microorganisms in traditional vinegar production.


Assuntos
Ácido Acético/isolamento & purificação , Ácido Acético/metabolismo , Acetobacter/crescimento & desenvolvimento , Acetobacter/metabolismo , Biotecnologia/métodos , Engenharia Metabólica/métodos , Acetobacter/genética , Aerobiose , Reatores Biológicos/microbiologia , Redes e Vias Metabólicas/genética
5.
Molecules ; 23(2)2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29473913

RESUMO

The flavoring of vinegars with aromatic fruits and medicinal herbs is a practice with increasing trend mostly in countries with oenological tradition, resulting in a product of improved quality and consumer attractiveness. This study was directed towards the evaluation of the impact of the maceration process on the volatile signature of wine-based aromatic vinegars (WBAVs). The evaluation was performed using solid phase microextraction (SPME) combined with gas chromatography combined with mass spectrometry (GC-MS). Experimental parameters influencing headspace solid (HS)-SPME extraction efficiency, were optimized using an univariate experimental design. The best results were achieved using a polydimethylsiloxane (PDMS) fiber, 10 mL of vinegar sample, at 50 °C for 30 min of extraction. This way One hundred and three volatile organic compounds (VOCs), belonging to different chemical families including ethyl esters (37), higher alcohols (20), fatty acids (10), terpenoids (23), carbonyl compounds (six), lactones (five) and volatile phenols (two), were identified in wine vinegar (control) and WBAV. As far as we know, 34 of these VOCs are reported for the first time in macerated vinegars. Higher alcohols and lactones are the major chemical families in WBAV macerated with apple, whereas terpenoids are predominant in WBAV macerated with banana. The obtained data represent a suitable tool to guarantee the authenticity and genuineness of WBAV, as well as to promote the production of WBAV with improved sensorial and organoleptic properties. To the best of our knowledge, there are no reported studies dealing with the volatile signature of WBAV enriched with banana, passion fruit, apple and pennyroyal.


Assuntos
Ácido Acético/química , Ácido Acético/metabolismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Vinho/análise , Ácido Acético/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Concentração Osmolar , Microextração em Fase Sólida , Temperatura
6.
Molecules ; 22(6)2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-28598364

RESUMO

Microalgae are recognized as a third generation feedstock for biofuel production due to their rapid growth rates and lignin-free characteristics. In this study, a lipid extracted microalgal biomass residues was used as the raw material to produce isoprene, α-pinene and ß-pinene with an engineered E. coli strain. We adopted an optimal sulfuric acid hydrolysis method (1:7 ratio of solid to acid solution, 32% (w/v) concentration of sulfuric acid solution at 90 °C for 90 min) to efficiently convert holocellulose into glucose efficiently (6.37 g/L). Futhermore, we explored a novel detoxification strategy (phosphoric acid/calcium hydroxide) to remove inhibitors and notably acetic acid, furfural and 5-hydroxymethylfurfural (5-HMF) were reduced by 5.32%, different number given later 99.19% and 98.22%, respectively. Finally, the fermentation concentrations of isoprene (223.23 mg/L), α-pinene (382.21 µg/L) and ß-pinene (17.4 mg/L) were achieved using the detoxified hydrolysate as the carbon source, equivalent to approximately 86.02%, 90.16% and 88.32% of those produced by the engineered E. coli strain fermented on pure glucose, respectively.


Assuntos
Compostos Bicíclicos com Pontes/metabolismo , Escherichia coli/metabolismo , Engenharia Genética/métodos , Hemiterpenos/biossíntese , Microalgas/química , Monoterpenos/metabolismo , Ácido Acético/isolamento & purificação , Monoterpenos Bicíclicos , Biocombustíveis , Biomassa , Compostos Bicíclicos com Pontes/isolamento & purificação , Butadienos/isolamento & purificação , Celulose/metabolismo , Escherichia coli/genética , Fermentação , Furaldeído/análogos & derivados , Furaldeído/isolamento & purificação , Glucose/metabolismo , Hemiterpenos/isolamento & purificação , Hidrólise , Cinética , Monoterpenos/isolamento & purificação , Pentanos/isolamento & purificação , Ácidos Sulfúricos/química
7.
Pharm Biol ; 55(1): 43-52, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27595296

RESUMO

CONTEXT: Fruit vinegars (FVs) are used in Mediterranean folk medicine for their hypolipidemic and weight-reducing properties. OBJECTIVE: To investigate the preventive effects of three types of FV, commonly available in Algeria, namely prickly pear [Opuntia ficus-indica (L.) Mill (Cectaceae)], pomegranate [Punica granatum L. (Punicaceae)], and apple [Malus domestica Borkh. (Rosaceae)], against obesity-induced cardiomyopathy and its underlying mechanisms. MATERIALS AND METHODS: Seventy-two male Wistar rats were equally divided into 12 groups. The first group served as normal control (distilled water, 7 mL/kg bw), and the remaining groups were respectively treated with distilled water (7 mL/kg bw), acetic acid (0.5% w/v, 7 mL/kg bw) and vinegars of pomegranate, apple or prickly pear (at doses of 3.5, 7 and 14 mL/kg bw, acetic acid content as mentioned above) along with a high-fat diet (HFD). The effects of the oral administration of FV for 18 weeks on the body and visceral adipose tissue (VAT) weights, plasma inflammatory and cardiac enzymes biomarkers, and in heart tissue were evaluated. RESULTS: Vinegars treatments significantly (p < .05) attenuated the HFD-induced increase in bw (0.2-0.5-fold) and VAT mass (0.7-1.8-fold), as well as increase in plasma levels of CRP (0.1-0.3-fold), fibrinogen (0.2-0.3-fold), leptin (1.7-3.7-fold), TNF-α (0.1-0.6-fold), AST (0.9-1.4-fold), CK-MB (0.3-1.4-fold) and LDH (2.7-6.7-fold). Moreover, vinegar treatments preserved myocardial architecture and attenuated cardiac fibrosis. DISCUSSION AND CONCLUSION: These findings suggest that pomegranate, apple and prickly pear vinegars may prevent HFD-induced obesity and obesity-related cardiac complications, and that this prevention may result from the potent anti-inflammatory and anti-adiposity properties of these vinegars.


Assuntos
Ácido Acético/farmacologia , Adiposidade/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Fármacos Antiobesidade/farmacologia , Dieta Hiperlipídica , Frutas/química , Lythraceae/química , Malus/química , Obesidade Abdominal/prevenção & controle , Opuntia/química , Extratos Vegetais/farmacologia , Ácido Acético/isolamento & purificação , Animais , Anti-Inflamatórios/isolamento & purificação , Fármacos Antiobesidade/isolamento & purificação , Biomarcadores/sangue , Peso Corporal/efeitos dos fármacos , Cardiomiopatias/sangue , Cardiomiopatias/patologia , Cardiomiopatias/prevenção & controle , Creatina Quinase Forma MB/sangue , Modelos Animais de Doenças , Fibrose , Mediadores da Inflamação/sangue , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/fisiopatologia , L-Lactato Desidrogenase/sangue , Masculino , Miocárdio/enzimologia , Miocárdio/patologia , Obesidade Abdominal/sangue , Obesidade Abdominal/etiologia , Obesidade Abdominal/fisiopatologia , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Ratos Wistar
8.
Klin Lab Diagn ; 62(2): 112-5, 2017 Feb.
Artigo em Russo | MEDLINE | ID: mdl-30615400

RESUMO

The volatile fatty acids are metabolites of bacteria reflecting condition and disbiotic alterations of microflora of gastrointestinal tract. The study was carried out to determine qualitatively volatile fatty acids in saliva of children with dysfunction of biliary tract and healthy ones. The indices of volatile fatty acids were analyzed in 46 children aged 7-17 years and with dysfunction of biliary tract. The comparison group included 34 healthy children aged from 7 to 17 years. The gas-liquid chromatography was applied to qualitatively detect acetic, butyric, isovaleric acids (volatile fatty acids). The automatedgas chromatograph "Crystal deluxe 4000" with capillary column "HP-FFAP" and flame ionizing detector was used. The study established decreasing of anaerobic index, increasing of acetic, propionic acids and sum of volatile fatty acids in saliva of children of main group as opposed to children of comparison group. The possible role of bacterial metabolites and bacteria in pathogenesis of dysfunction of biliary tract in children. The description is made of one of possible mechanisms of increasing of volatile fatty acids in saliva under dysfunction of biliary tract. The integral indices of volatile fatty acids of saliva are the new additional criteria for diagnostic of dysfunction of biliary tract in children.


Assuntos
Doenças Biliares/metabolismo , Sistema Biliar/metabolismo , Ácidos Graxos Voláteis/isolamento & purificação , Saliva/química , Ácido Acético/isolamento & purificação , Ácido Acético/metabolismo , Adolescente , Bactérias/metabolismo , Sistema Biliar/química , Sistema Biliar/microbiologia , Sistema Biliar/patologia , Doenças Biliares/diagnóstico , Doenças Biliares/microbiologia , Doenças Biliares/patologia , Ácido Butírico/isolamento & purificação , Ácido Butírico/metabolismo , Criança , Cromatografia Gasosa , Ácidos Graxos Voláteis/metabolismo , Feminino , Hemiterpenos , Humanos , Masculino , Ácidos Pentanoicos/isolamento & purificação , Ácidos Pentanoicos/metabolismo , Propionatos/isolamento & purificação
9.
Pharm Biol ; 54(2): 260-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25853952

RESUMO

CONTEXT: Vinegar has long been used as a condiment and a traditional medicine worldwide. OBJECTIVE: The current study investigates the antioxidant effect of three types of fruit vinegars (FV) namely pomegranate [Punica granatum L. (Punicaceae)], prickly pear [Opuntia ficus-indica (L.) Mill. (Cactaceae)], and apple [Malus domestica Borkh. (Rosaceae)] vinegars in high-fat diet (HFD)-induced hyperlipidemic Wistar rats. MATERIALS AND METHODS: Fifty male Wistar rats were divided into five groups; HFD (80 cal/d) fed rats were orally dosed with fruit vinegars (7 ml/kg) once daily for 28 weeks. At the end of the experiment, lipid profile, lipid peroxidation products, antioxidant enzymes, and trace elements were assessed in serum. In addition, a liver histopathological study was performed. RESULTS: HFD showed a significant increase (p ≤ 0.05) in lipid profile and TBARS levels when compared with normal control. Daily oral administration of FV normalized various biochemical, metabolic, and histopathological changes. However, pomegranate vinegar exhibited a very significant (p ≤ 0.001) reduction in lipid profile levels (total cholesterol: 165%, triglycerides: 68%, LDL-c: 76%, and atherogenic index: 80%), whereas an increase in antioxidant status (SOD: 7-fold, GPx: 4.81-fold, GRx: 1.66-fold, and TAS: 3.45-fold) when compared with hyperlipidemic control. Histopathological examinations also confirmed the protective effects of pomegranate vinegar against lipid accumulation and the improvement of hepatic lesions. DISCUSSION AND CONCLUSION: The fruit vinegars regulate lipid metabolism and decrease liver damage in high-fat fed rats as shown in this study.


Assuntos
Ácido Acético/uso terapêutico , Antioxidantes/uso terapêutico , Dislipidemias/prevenção & controle , Frutas/química , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ácido Acético/isolamento & purificação , Ácido Acético/farmacologia , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/administração & dosagem , Modelos Animais de Doenças , Dislipidemias/etiologia , Dislipidemias/metabolismo , Dislipidemias/patologia , Fermentação , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Polifenóis/análise , Ratos Wistar
10.
Environ Sci Technol ; 48(20): 11803-10, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25251872

RESUMO

Interaction between the goethite surface and 4-chloro-2-methylphenoxyacetic acid (MCPA) herbicide was studied using density functional theory (DFT) calculations combined with molecular dynamics (MD). The important step made here lies in the use of a periodic DFT method enabling the study of a mineral surface of different protonation states, in strong contrast with previous molecular modeling studies limited to single protonation state corresponding to the point of zero charge. Different surface OH groups and MCPA proton states were used to mimic the strong effects of pH on the outer- and inner-sphere surface complexes that are theoretically possible, together with their binding energies, and their bond lengths. Modeling both a solvated and a protonated (110) goethite surface provided a major breakthrough in the acidic adsorption regime. An outer-sphere complex and a monodentate inner-sphere complex with the neutral MCPA molecule were found to be the most energetically stable adsorbate forms. MD modeling predicted that the latter forms via the sharing of the carbonyl oxygen between the MCPA carboxylate group and a singly coordinated surface hydroxyl group, releasing an H2O molecule. All the other complexes, including the bidentate inner-sphere complex, had higher relative energies and were therefore less likely. The two most likely DFT-optimized structures were used to constrain a surface complexation model applying the charge distribution multisite complexation (CD-MUSIC) approach. The adsorption constants for the complexes were successfully fitted to experimental batch equilibrium data.


Assuntos
Ácido Acético/isolamento & purificação , Herbicidas/isolamento & purificação , Compostos de Ferro/química , Minerais/química , Adsorção , Fracionamento Químico , Meio Ambiente , Concentração de Íons de Hidrogênio , Modelos Teóricos , Simulação de Dinâmica Molecular , Propriedades de Superfície
11.
Biotechnol Bioeng ; 108(9): 2046-52, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21455937

RESUMO

In the cellulosic ethanol process, furfural, 5-hydroxymethylfurfural (HMF), and acetic acid are formed during the high temperature acidic pretreatment step needed to convert biomass into fermentable sugars. These compounds can inhibit cellulase enzymes and fermentation organisms at relatively low concentrations (≥ 1 g/L). Effective removal of these inhibitory compounds would allow the use of more severe pretreatment conditions to improve sugar yields and lead to more efficient fermentations; if recovered and purified, they could also be sold as valuable by-products. This study investigated the separation of aldhehydes (furfural and HMF) and organic acid (acetic acid) inhibitory compounds from simple aqueous solutions by using polyethyleneimene (PEI), a soluble cationic polyelectrolyte. PEI added to simple solutions of each inhibitor at a ratio of 1 mol of functional group to 1 mol inhibitor removed up to 89.1, 58.6, and 81.5 wt% of acetic acid, HMF, and furfural, respectively. Furfural and HMF were recovered after removal by washing the polyelectrolyte/inhibitor complex with dilute sulfuric acid solution. Recoveries up to 81.0 and 97.0 wt% were achieved for furfural and HMF, respectively. The interaction between PEI and acetic acid was easily disrupted by the addition of chloride ions, sulfate ions, or hydroxide ions. The use of soluble polymers for the removal and recovery of inhibitory compounds from biomass slurries is a promising approach to enhance the efficiency and economics of an envisioned biorefinery.


Assuntos
Ácido Acético/isolamento & purificação , Fracionamento Químico/métodos , Furaldeído/análogos & derivados , Furaldeído/isolamento & purificação , Polietilenoimina/química , Ácido Acético/química , Biomassa , Furaldeído/química , Modelos Químicos , Solubilidade , Gerenciamento de Resíduos
12.
Bioprocess Biosyst Eng ; 34(7): 779-87, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21350956

RESUMO

Biotechnologically produced succinic acid has the potential to displace maleic acid and its uses and to become an important feedstock for the chemical industry. In addition to optimized production strains and fermentation processes, an efficient separation of succinic acid from the aqueous fermentation broth is indispensable to compete with the current petrochemical production processes. In this context, high molecular weight amines are known to be effective extractants for organic acids. For this reason, as a first step of isolation and purification, the reactive extraction of succinic acid was studied by mixing aqueous succinic acid solutions with 448 different amine-solvent mixtures as extraction agents (mixer-settler studies). The extraction agents consist either of one amine and one solvent (208 reactive extraction systems) or two amines and two solvents (240 reactive extraction systems). Maximum extraction yields of succinic acid from an aqueous solution with 423 mM succinic acid at pH 2.0 were obtained with more than 95% yield with trihexylamine solved in 1-octanol or with dihexylamine and diisooctylamine solved in 1-octanol and 1-hexanol. Applying these optimized reactive extraction systems with Escherichia coli fermentation broth resulted in extraction yields of 78-85% due to the increased ionic strength of the fermentation supernatant and the co-extraction of other organic acids (e.g., lactic acid and acetic acid), which represent typical fermentation byproducts.


Assuntos
1-Octanol/química , Aminas/química , Hexanóis/química , Extração Líquido-Líquido/métodos , Solventes/química , Ácido Succínico/isolamento & purificação , Ácido Acético/isolamento & purificação , Biotecnologia/métodos , Indústria Química/métodos , Escherichia coli/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Íons/química , Ácido Láctico/isolamento & purificação , Compostos Orgânicos/química , Concentração Osmolar , Água/química
13.
J Oleo Sci ; 69(7): 767-770, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32522942

RESUMO

The volatile components produced by Leptolejeunea elliptica (Lejeuneaceae), which is a liverwort grown on the leaves of tea (Camellia sinensis), were collected and analyzed using headspace solid-phase microextraction-gas chromatography/mass spectrometry (HS-SPME-GC/MS). 1-Ethyl-4-methoxybenzene (1), 1-ethyl-4-hydroxybenzene (2), and 1-acetoxy-4-ethylbenzene (3) were identified as the major components together with several other phenolic compounds, including 1,2-dimethoxy-4-ethylbenzene, and 4-ethylguaiacol in addition to sesquiterpene hydrocarbons, such as α-selinene, ß-selinene, ß-elemene, and ß-caryophyllene. GC/Olfactometry showed the presence of linalool, acetic acid, isovaleric acid, trans-methyl cinnamate, and trans-4,5-epoxy-(2E)-decenal, as the volatile components produced by L. elliptica.


Assuntos
Hepatófitas/metabolismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação , Ácido Acético/análise , Ácido Acético/isolamento & purificação , Anisóis/análise , Anisóis/isolamento & purificação , Derivados de Benzeno/análise , Derivados de Benzeno/isolamento & purificação , Camellia sinensis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Japão , Olfatometria , Fenol/análise , Fenol/isolamento & purificação , Fenóis/análise , Fenóis/isolamento & purificação , Sesquiterpenos Policíclicos/análise , Sesquiterpenos Policíclicos/isolamento & purificação , Sesquiterpenos/análise , Sesquiterpenos/isolamento & purificação , Microextração em Fase Sólida/métodos
14.
Nutrients ; 12(1)2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31963184

RESUMO

Ginkgo seed coat is rarely used and is typically discarded, due to its offensive odor and its toxicity. Ginkgo vinegar is a fermented product of ginkgo seed coat, and fermentation removes the bad smell and most of the toxicity. Thus, ginkgo vinegar contains very low concentrations of toxic components. The present study examined the anti-obesity effect of ginkgo vinegar in mice fed a high-fat diet and its inhibition of adipogenesis in 3T3-L1 cells. Ginkgo vinegar suppressed high-fat diet-induced body weight gain and reduced the size of fat cells in mice. Ginkgo vinegar suppressed the expression of C/EBPδ and PPARγ, key proteins in adipogenesis, and inhibited lipid accumulation in 3T3-L1 cells that were induced to become adipocytes. These results suggested that ginkgo vinegar inhibited adipocyte differentiation. On the other hand, a corresponding concentration of acetic acid had significantly less effect on lipid accumulation and virtually no effect on adipogenic gene expression. These results suggested that, similar to Ginkgo biloba extract, ginkgo vinegar might prevent and improve adiposity. Therefore, ginkgo seed coat could be a useful material for medicinal ingredients.


Assuntos
Ácido Acético/farmacologia , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Dieta Hiperlipídica , Ginkgo biloba , Obesidade/prevenção & controle , Extratos Vegetais/farmacologia , Sementes , Células 3T3 , Ácido Acético/isolamento & purificação , Adipócitos/metabolismo , Adipogenia/genética , Animais , Fármacos Antiobesidade/isolamento & purificação , Proteína delta de Ligação ao Facilitador CCAAT/genética , Proteína delta de Ligação ao Facilitador CCAAT/metabolismo , Modelos Animais de Doenças , Fermentação , Ginkgo biloba/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/genética , Obesidade/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Extratos Vegetais/isolamento & purificação , Sementes/química , Redução de Peso/efeitos dos fármacos
15.
Water Res ; 43(6): 1597-610, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19232668

RESUMO

This study evaluated pilot-scale photocatalysis and enhanced coagulation for their ability to remove or destroy disinfection byproduct (DBP) precursors, trihalomethane (THM) formation potential (FP), and THMs in two Arizona surface waters. Limited photocatalysis (<5 kWh/m(3)) achieved reductions in most of the DBP precursor parameters (e.g., DOC, UV(254), and bromide) but led to increased chlorine demand and THMFP. In contrast, enhanced coagulation achieved reductions in the DBP precursors and THMFP. Extended photocatalysis (<320 kWh/m(3)) decreased THMFP once the energy consumption exceeded 20 kWh/m(3). The photocatalytic energy requirements for THM destruction were considerably lower (EEO=20-60 kWh/m(3)) than when focusing on precursor destruction and THMFP. However, rechlorination increased the total THM (TTHM) concentration well beyond the raw value, thereby negating the energy benefits of this application. Enhanced coagulation achieved consistent 20-30% removals of preformed THMs. Outstanding issues need to be addressed before TiO(2) photocatalysis is considered feasible for DBP mitigation; traditional strategies, including enhanced coagulation, may be more appropriate.


Assuntos
Catálise , Desinfecção/métodos , Fotoquímica , Projetos Piloto , Ácido Acético/isolamento & purificação , Arizona , Bromatos/isolamento & purificação , Cloretos/isolamento & purificação , Clima Desértico , Halogenação , Concentração de Íons de Hidrogênio , Nefelometria e Turbidimetria , Cloreto de Sódio/análise , Trialometanos/isolamento & purificação , Raios Ultravioleta
16.
J Hazard Mater ; 162(2-3): 1278-84, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18639982

RESUMO

Recovery of acetic acid (HAc) from the waste etching solution discharged from silicon wafer manufacturing process has been attempted by using solvent extraction process. For this purpose 2-ethylhexyl alcohol (EHA) was used as organic solvent. In the pre-treatment stage >99% silicon and hydrofluoric acid was removed from the solution by precipitation. The synthesized product, Na(2)SiF(6) having 98.2% purity was considered of commercial grade having good market value. The waste solution containing 279 g/L acetic acid, 513 g/L nitric acid, 0.9 g/L hydrofluoric acid and 0.030 g/L silicon was used for solvent extraction study. From the batch test results equilibrium conditions for HAc recovery were optimized and found to be 4 stages of extraction at an organic:aqueous (O:A) ratio of 3, 4 stages of scrubbing and 4 stages of stripping at an O:A ratio of 1. Deionized water (DW) was used as stripping agent to elute HAc from organic phase. In the whole batch process 96.3% acetic acid recovery was achieved. Continuous operations were successfully conducted for 100 h using a mixer-settler to examine the feasibility of the extraction system for its possible commercial application. Finally, a complete process flowsheet with material balance for the separation and recovery of HAc has been proposed.


Assuntos
Ácido Acético/isolamento & purificação , Ácidos/química , Semicondutores , Solventes/química , Difração de Raios X
17.
Appl Biochem Biotechnol ; 187(1): 378-395, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29961903

RESUMO

Pre-pulping extraction is a means of deriving a hemicellulose-rich process stream from the front end of a kraft pulp mill. When the extraction is carried out using green liquor, pulp quality and quantity can be retained while still releasing hemicelluloses and acetic acid (HAc) for recovery as bioprocessing feedstock or chemical products. The HAc that is present in the wood extraction is inhibitory to microorganisms and can hinder fermentation. HAc is also a commodity chemical that may provide sufficient value to justify recovery and purification. In this study, a liquid-liquid extraction (LLE) method is applied to extract HAc from a green liquor pre-pulping hardwood extract (GLE). The HAc removal is carried out after acid hydrolysis and prior to fermentation. Two organic solutions: trioctylphosphine oxide (TOPO) diluted in undecane and trioctylamine (TOA) diluted in octanol were tested for their abilities to extract HAc from GLE and to be recycled back through the process. GLE was contacted with the organic solvents, phase separated by centrifugation, and the organic phase was then distilled to recover the acetic acid. The solvent was then recycled back for a subsequent extraction of fresh GLE. It was found that TOA was a superior extractant, but failed to easily release its HAc through distillation. It also quickly became contaminated with other compounds in the wood extracts and lost its extraction efficiency after only a few recycles. The TOPO solvent did release its HAc through distillation but also lost extraction capacity with recycling. Back extraction of the TOPO solvent with sodium hydroxide solution restored the performance of the TOPO solvent.


Assuntos
Ácido Acético/isolamento & purificação , Alcanos/química , Octanóis/química , Polissacarídeos/isolamento & purificação , Reciclagem , Solventes/química , Madeira/química , Aminas/química , Centrifugação , Fermentação , Temperatura Alta , Concentração de Íons de Hidrogênio , Compostos Organofosforados/química , Soluções , Água
18.
Anim Reprod Sci ; 103(1-2): 149-53, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17507187

RESUMO

Ten different volatile compounds were detected in bovine faeces using three chromatograms. The chemical profiles of estrus faeces were distinguished significantly from other phases by the presence of three specific substances, viz. acetic acid and propionic acid and 1-iodo undecane. The estrus specific synthetic compounds were rubbed onto the genital region of nonestrus animals (dummy cows), and the bulls were allowed to sniff the genital region and observed sexual behaviours. The statistical significance was higher (P<0.001) in bulls exhibiting repeated flehmen and mounting behaviours towards the mixture of acetic acid, propionic acid and 1-iodo undecane. The bioassay revealed that the fatty acids viz., acetic acid; propionic acid and 1-iodo undecane produced in faeces during estrus appear to be estrus specific. The results suggest that these compounds may be used as estrus indicator in cow, probably involved in bovine biocommunication.


Assuntos
Bovinos/metabolismo , Detecção do Estro/métodos , Fezes/química , Atrativos Sexuais/análise , Ácido Acético/isolamento & purificação , Alcanos/isolamento & purificação , Animais , Feminino , Masculino , Propionatos/isolamento & purificação , Atrativos Sexuais/metabolismo , Comportamento Sexual Animal/fisiologia
19.
J Chromatogr A ; 1562: 47-58, 2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-29859683

RESUMO

An intermittent simulated moving bed (3F-ISMB) operation scheme, the extension of the 3W-ISMB to the non-linear adsorption region, has been introduced for separation of glucose, lactic acid and acetic acid ternary-mixture. This work focuses on exploring the feasibility of the proposed process theoretically and experimentally. Firstly, the real 3F-ISMB model coupled with the transport dispersive model (TDM) and the Modified-Langmuir isotherm was established to build up the separation parameter plane. Subsequently, three operating conditions were selected from the plane to run the 3F-ISMB unit. The experimental results were used to verify the model. Afterwards, the influences of the various flow rates on the separation performances were investigated systematically by means of the validated 3F-ISMB model. The intermittent-retained component lactic acid was finally obtained with the purity of 98.5%, recovery of 95.5% and the average concentration of 38 g/L. The proposed 3F-ISMB process can efficiently separate the mixture with low selectivity into three fractions.


Assuntos
Técnicas de Química Analítica/métodos , Ácido Láctico/isolamento & purificação , Ácido Acético/isolamento & purificação , Adsorção , Técnicas de Química Analítica/instrumentação , Glucose/isolamento & purificação
20.
Sci Rep ; 8(1): 1732, 2018 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-29379012

RESUMO

The global escalation in antibiotic resistance cases means alternative antimicrobials are essential. The aim of this study was to investigate the antimicrobial capacity of apple cider vinegar (ACV) against E. coli, S. aureus and C. albicans. The minimum dilution of ACV required for growth inhibition varied for each microbial species. For C. albicans, a 1/2 ACV had the strongest effect, S. aureus, a 1/25 dilution ACV was required, whereas for E-coli cultures, a 1/50 ACV dilution was required (p < 0.05). Monocyte co-culture with microbes alongside ACV resulted in dose dependent downregulation of inflammatory cytokines (TNFα, IL-6). Results are expressed as percentage decreases in cytokine secretion comparing ACV treated with non-ACV treated monocytes cultured with E-coli (TNFα, 99.2%; IL-6, 98%), S. aureus (TNFα, 90%; IL-6, 83%) and C. albicans (TNFα, 83.3%; IL-6, 90.1%) respectively. Proteomic analyses of microbes demonstrated that ACV impaired cell integrity, organelles and protein expression. ACV treatment resulted in an absence in expression of DNA starvation protein, citrate synthase, isocitrate and malate dehydrogenases in E-coli; chaperone protein DNak and ftsz in S. aureus and pyruvate kinase, 6-phosphogluconate dehydrogenase, fructose bisphosphate were among the enzymes absent in C.albican cultures. The results demonstrate ACV has multiple antimicrobial potential with clinical therapeutic implications.


Assuntos
Ácido Acético/farmacologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Malus/química , Monócitos/efeitos dos fármacos , Ácido Acético/isolamento & purificação , Anti-Infecciosos/isolamento & purificação , Citocinas/metabolismo , Fatores Imunológicos/isolamento & purificação , Testes de Sensibilidade Microbiana , Proteoma/análise
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