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1.
Materials (Basel) ; 16(17)2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37687541

RESUMEN

One method of managing used car tires is decomposition by thermochemical conversion methods. By conducting the process at temperatures of 450-750 °C, three fractions are obtained from tires: oil, gas, and solid. The liquid product of the pyrolysis of used car tires is pyrolysis oil, which consists of aromatic, polyaromatic, and aliphatic hydrocarbons. Unconventional building materials were obtained from tire pyrolysis oil and the environmental impact was evaluated. Blocks made from pyrolysis oil showed mechanical strength of up to about 1700 N. No heavy metals or polycyclic aromatic hydrocarbons, which were found in the crude heavy-PO fraction, were detected in the filtrates after incubation of the block obtained from the heavy-PO fraction at 240 °C. The highest inhibition of Sorghum saccharatum shoot (74.4%) and root (57.5%) growth was observed for solid materials from the medium-PO fraction obtained at 240 °C. The most favorable values of the parameters for the process of obtaining blocks based on post-PO were an annealing temperature of 180 °C, time of 20 h, and mass ratio of catalyst to catalyzed oil of 0.045.

2.
Insects ; 13(10)2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36292852

RESUMEN

Fallopia baldschuanica (Polygonaceae) is an Asian plant growing wild in parts of Europe and North and Central America as an introduced taxon, in many countries it is considered a potentially invasive species. This article presents the list of 18 volatile organic compounds (VOCs) emitted by the flowers of F. baldchuanica and identified by headspace gas chromatography/mass spectrometry (HS-GC/MS) analyzes, and a list of flower-visiting and pollinating insects that have been observed in the city center of Wroclaw (SW Poland). ß-ocimene, heptanal, nonanal, α-pinene, 3-thujene, and limonene, were detected as the floral scent's most important aroma compounds. F. baldschuanica also produces the aphid alarm pheromones, i.e., ß-farnesene and limonene, that repels aphids. Additionally, the pollinators of F. baldschuanica were indicated, based on two years of observations in five sites in the urban area. It was found, that the pollinators of this plant with the highest species stability are: Diptera from families Syrphidae (Chrysotoxum bicinctum, Eristalis pertinax, Eupeodes corollae, Episyrphus balteatus, Eristalis tenax, Syrphus ribesii, Eristalis intricaria), Muscidae (Musca domestica), Sarcophagidae (Sarcophaga spp.), Calliphoridae (Lucilia sericata, Lucilia caesar), Hymenoptera from families Vespidae (Vespula vulgaris), and Apidae (Apis sp., Bombus sp.). The key role of VOCs in adaptation to plant expansion is discussed.

3.
Biomolecules ; 11(2)2021 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-33514072

RESUMEN

Eugenyl-ß-D-glucopyranoside, also referred to as Citrusin C, is a natural glucoside found among others in cloves, basil and cinnamon plants. Eugenol in a form of free aglycone is used in perfumeries, flavourings, essential oils and in medicinal products. Synthetic Citrusin C was incubated with human saliva in several in vitro models together with substrate-specific enzyme and antibiotics (clindamycin, ciprofloxacin, amoxicillin trihydrate and potassium clavulanate). Citrusin C was detected using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Citrusin C was completely degraded only when incubated with substrate-specific A. niger glucosidase E.C 3.2.1.21 (control sample) and when incubated with human saliva (tested sample). The addition of antibiotics to the above-described experimental setting, stopped Citrusin C degradation, indicating microbiologic origin of hydrolysis observed. Our results demonstrate that Citrusin C is subjected to complete degradation by salivary/oral cavity microorganisms. Extrapolation of our results allows to state that in the human oral cavity, virtually all ß-D-glucosides would follow this type of hydrolysis. Additionally, a new method was developed for an in vivo rapid test of glucosidase activity in the human mouth on the tongue using fluorescein-di-ß-D-glucoside as substrate. The results presented in this study serve as a proof of concept for the hypothesis that microbial hydrolysis path of ß-D-glucosides begins immediately in the human mouth and releases the aglycone directly into the gastrointestinal tract.


Asunto(s)
Fluoresceína/química , Glucósidos/metabolismo , Saliva/metabolismo , Antibacterianos/farmacología , Cromatografía Liquida , Tracto Gastrointestinal/metabolismo , Glucósidos/química , Voluntarios Sanos , Humanos , Hidrólisis , Técnicas In Vitro , Kéfir , Cinética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem , beta-Glucosidasa/metabolismo
4.
Int J Mol Sci ; 21(24)2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-33327555

RESUMEN

Helicobacter pylori is a bacterium known mainly of its ability to cause persistent inflammations of the human stomach, resulting in peptic ulcer diseases and gastric cancers. Continuous exposure of this bacterium to antibiotics has resulted in high detection of multidrug-resistant strains and difficulties in obtaining a therapeutic effect. The purpose of the present study was to determine the usability of bacterial cellulose (BC) chemisorbed with 3-bromopyruvate (3-BP) or sertraline (SER) to act against lawn H. pylori biofilms. The characterization of BC carriers was made using a N2 adsorption/desorption analysis, tensile strength test, and scanning electron microscopy (SEM) observations. Determination of an antimicrobial activity was performed using a modified disk-diffusion method and a self-designed method of testing antibacterial activity against biofilm microbial forms. In addition, bacterial morphology was checked by SEM. It was found that BC disks were characterized by a high cross-linking and shear/stretch resistance. Growth inhibition zones for BC disks chemisorbed with 2 mg of SER or 3-BP were equal to 26.5-27.5 mm and 27-30 mm, respectively. The viability of lawn biofilm H. pylori cells after a 4-h incubation with 2 mg SER or 3-BP chemisorbed on BC disks was ≥4 log lower, suggesting their antibacterial effect. SEM observations showed a number of morphostructural changes in H. pylori cells exposed to these substances. Concluding, SER and 3-BP chemisorbed on BC carriers presented a promising antibacterial activity against biofilm H. pylori cells in in vitro conditions.


Asunto(s)
Celulosa/metabolismo , Piruvatos/metabolismo , Sertralina/metabolismo , Biopelículas/crecimiento & desarrollo , Helicobacter pylori/crecimiento & desarrollo , Helicobacter pylori/metabolismo , Helicobacter pylori/ultraestructura , Pruebas de Sensibilidad Microbiana
5.
Int J Mol Sci ; 21(8)2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32326145

RESUMEN

In mammalian cells, 3-hydroxybutyrate (3-HB) is not only an intermediate metabolite during the oxidation of fatty acids, but also an important signaling molecule. On the other hand, the information about the metabolism or function of this compound in plants is scarce. In our study, we show for the first time that this compound naturally occurs in flax. The expression of bacterial ß-ketothiolase in flax affects expression of endogenous genes of the 3-HB biosynthesis pathway and the compound content. The increase in 3-HB content in transgenic plants or after control plants treatment with 3-HB resulted in upregulation of genes involved in chromatin remodeling. The observation that 3-HB is an endogenous activator of methyltransferase 3 (CMT3), decreased DNA methylation I (DDM1), DEMETER DNA glycosylase (DME), and an inhibitor of sirtuin 1 (SRT1) provides an example of integration of different genes in chromatin remodeling. The changes in chromatin remodeling gene expression concomitant with those involved in phenolics and the lignin biosynthesis pathway suggest potential integration of secondary metabolic status with epigenetic changes.


Asunto(s)
Ácido 3-Hidroxibutírico/metabolismo , Metilación de ADN , Lino/genética , Lino/metabolismo , Regulación de la Expresión Génica de las Plantas , Ácido 3-Hidroxibutírico/farmacología , Epigénesis Genética , Lino/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas , Redes y Vías Metabólicas , Plantas Modificadas Genéticamente , Propanoles/metabolismo , ARN Mensajero , Espectroscopía Infrarroja por Transformada de Fourier
6.
J Biomed Mater Res B Appl Biomater ; 108(1): 30-37, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-30883023

RESUMEN

Bacterial cellulose is one of the most promising polymers of recent years. Herein, we present a possibility of BC application as a carrier of gentamycin antibiotic for the treatment and prevention of bone infections. We have shown that BC saturated with gentamycin significantly reduces the level of biofilm-forming bone pathogens, namely Staphylococcus aureus and Pseudomonas aeruginosa, and displays very low cytotoxicity in vitro against osteoblast cell cultures. Another beneficial feature of our prototype dressing is prolonged release of gentamycin, which provides efficient protection from microbial contamination and subsequent infection. Moreover, it seems that bacterial cellulose (BC) alone without any antimicrobial added, may serve as a barrier by significantly hampering the ability of the pathogen to penetrate to the bone structure. Therefore, a gentamycin-saturated BC dressing may be considered as a possible alternative for gentamycin collagen sponge broadly used in clinical setting. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:30-37, 2020.


Asunto(s)
Vendajes , Biopelículas/efectos de los fármacos , Celulosa/química , Fémur/microbiología , Gentamicinas , Osteoblastos/microbiología , Pseudomonas aeruginosa/fisiología , Staphylococcus aureus/fisiología , Animales , Biopelículas/crecimiento & desarrollo , Línea Celular , Fémur/metabolismo , Gentamicinas/química , Gentamicinas/farmacocinética , Gentamicinas/farmacología , Humanos , Osteoblastos/metabolismo , Ratas
7.
Sci Rep ; 9(1): 1256, 2019 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-30718663

RESUMEN

In this research, bacterial cellulose (BC), one of the most promising biopolymers of the recent years, was saturated with thyme, eucalyptus and clove essential oils (EOs) and applied against staphylococcal and pseudomonal biofilms formed on hydroxyapatite (HA). BC dressings were thoroughly analyzed with regard to their physical properties. Moreover, the exact composition and ability of particular EO molecules to adhere to HA was assessed. Additionally, cytotoxicity of oil-containing, cellulose-based dressings towards osteoblasts and fibroblasts as well as their impact on reactive oxygen species (ROS) production by macrophages was assessed. The results revealed the high ability of BC dressings to absorb and subsequently release EOs from within their microstructure; the highest number of compounds able to adhere to HA was found in the thyme EO. The eucalyptus EO displayed low, while thyme and clove EOs displayed high cytotoxicity towards fibroblast and osteoblast cell lines. The clove EO displayed the highest eradication ability toward staphylococcal, while the thyme EO against pseudomonal biofilm. Taken together, the results obtained indicate the suitability of EO-saturated BC dressings to eradicate pseudomonal and staphylococcal biofilm on HA surface and moreover, to not trigger reactive oxygen species production by immune system effector cells. However, due to cytotoxic effects of thyme and clove EOs towards cell lines in vitro, the eucalyptus EO-saturated BC dressing is of highest potential to be further applied.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Celulosa/farmacología , Aceites Volátiles/farmacología , Polisacáridos Bacterianos/farmacología , Antibacterianos/química , Celulosa/química , Durapatita/química , Eucalyptus/química , Humanos , Aceites Volátiles/química , Polisacáridos Bacterianos/análogos & derivados , Infecciones por Pseudomonas/prevención & control , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/fisiología , Infecciones Estafilocócicas/prevención & control , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Syzygium/química , Thymus (Planta)/química
8.
J Microbiol Methods ; 143: 6-12, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28962915

RESUMEN

In the present article, we propose a simple Antibiofilm Dressing's Activity Measurement (A.D.A.M.) test that allows to check in vitro a dressing's suitability against biofilm-related wound infections. To perform the test, three agar discs are covered with biofilm formed by the tested pathogen after which they are assembled one over another in the form of an agar plug and placed in the well of a 24-well plate. The top disc is covered with the analyzed dressing and the entire set is incubated for 24h. During this time, the investigated antimicrobial substance is released from the dressing and penetrates to subsequent biofilm-covered agar discs. Biofilm reduction is measured using 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) spectrometric assay and the results are compared to untreated control samples (agar plug covered with biofilm and without the dressing/or with a passive dressing placed on the top disc). Furthermore, in order to standardize the differences in penetrability of the drugs released from active dressings the results can be expressed as a dimensionless value referred to as the Penetrability Index. In summary, A.D.A.M. test is simple, cheap, can be performed practically in every clinical laboratory and takes no more time than routine microbiological diagnostics. Apart from measuring the released drug's activity, the A.D.A.M. test allows to assess drug penetrability (across three agar discs), reflecting real wound conditions, where microbes are frequently hidden under the necrotic tissue or cloth. In conclusion, the A.D.A.M. test produces a high volume of data that, when analyzed, can provide a researcher with a valuable hint concerning the applicability of active dressings against specific biofilm pathogens in a particular setting.


Asunto(s)
Antibacterianos/farmacología , Antibacterianos/farmacocinética , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Vendajes/microbiología , Biopelículas/efectos de los fármacos
9.
J Pharm Biomed Anal ; 137: 13-22, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-28088662

RESUMEN

Chronic leg ulceration is a disease usually associated with other comorbidities, and significantly reduces patient quality of life. Infected leg ulcers can lead to limb-threatening sequelae or mortality. Leg ulcerations are colonized by a number of microbes that are able to cause life-threating infections in susceptible patients. Wound exudate is a body fluid that collects metabolites from patient eukaryotic cells and from prokaryotic bacterial communities inhabiting the wound. This study aimed at identification of metabolites in exudates collected from chronic leg ulcers, and correlation of this metabolome with patient comorbidities and microbiological status of the wound. By means of NMR spectroscopy we detected 42 metabolites of microbial or patient origin. The metabolites that were in abundance in exudates analyzed were lactate, lysine, and leucine. Metabolites were associated with the presence of neutrophils in wounds and destruction of high quantities of microbes, but also with hypoxia typical for venous insufficiency. The combination of nuclear magnetic resonance spectroscopy technique and partial least squares discriminant analysis allowed us to further discriminate groups of metabolites with regards to potential clinical meaning. For example, to discriminate between S.aureus versus all other isolated microbial species, or between patients suffering from type I or II diabetes versus patients without diabetes. Therefore, wound exudate seems to be highly applicable material for discriminant analysis performed with the use of NMR technique to provide for rapid metabolomics of chronic wound status.


Asunto(s)
Líquidos Corporales/metabolismo , Complicaciones de la Diabetes/metabolismo , Pierna/patología , Metaboloma/fisiología , Cicatrización de Heridas/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Complicaciones de la Diabetes/patología , Diabetes Mellitus/metabolismo , Femenino , Humanos , Espectroscopía de Resonancia Magnética/métodos , Masculino , Metabolómica/métodos , Persona de Mediana Edad
10.
Carbohydr Polym ; 157: 371-379, 2017 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-27987940

RESUMEN

The study aimed at evaluation of various types of alkali rinsing with regard to their efficacy in terms of removal, not only of bacteria but also bacterial metabolites, from cellulose matrices formed by three Komagataeibacter xylinus strains. Moreover, we tested the type of alkali rinsing on membrane cytotoxicity in vitro in fibroblast and osteoblast cells and we compared matrices' ability to induce oxidative stress in macrophages. We identified 11 metabolites of bacterial origin that remained in cellulose after rinsing. Moreover, our results indicated that the type of alkali rinsing should be adjusted to specific K. xylinus strains that are used as cellulose producers to obtain safe biomaterials in the context of low cytotoxicity and macrophage induction. The findings have translational importance and may be of direct significance to cellulose dressing manufacturers.


Asunto(s)
Materiales Biocompatibles , Celulosa/química , Gluconacetobacter xylinus/química , Álcalis , Animales , Vendajes , Línea Celular , Fibroblastos/efectos de los fármacos , Humanos , Macrófagos/efectos de los fármacos , Ratones , Osteoblastos/efectos de los fármacos
11.
Front Plant Sci ; 7: 1951, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28163709

RESUMEN

Flax (Linum usitatissimum) is a crop plant valued for its oil and fiber. Unfortunately, large losses in cultivation of this plant are caused by fungal infections, with Fusarium oxysporum being one of its most dangerous pathogens. Among the plant's defense strategies, changes in the expression of genes of the shikimate/phenylpropanoid/benzoate pathway and thus in phenolic contents occur. Among the benzoates, salicylic acid, and its methylated form methyl salicylate play an important role in regulating plants' response to stress conditions. Upon treatment of flax plants with the fungus we found that methyl salicylate content increased (4.8-fold of the control) and the expression profiles of the analyzed genes suggest that it is produced most likely from cinnamic acid, through the ß-oxidative route. At the same time activation of some genes involved in lignin and flavonoid biosynthesis was observed. We suggest that increased methyl salicylate biosynthesis during flax response to F. oxysporum infection may be associated with phenylpropanoid pathway activation.

12.
Food Chem ; 190: 412-418, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26212990

RESUMEN

Four synthesized terpenyl-ß-D-glycopyranosides (geranyl, neryl, citronellyl, myrtenyl) were subjected to enzymatic (AR 2000, pH 5.5) and acid (citric buffer, pH 2.5) hydrolysis. Decrease of glycosides was measured by HPLC and the volatiles released--by comprehensive gas chromatography-mass spectrometry (GC × GC-ToF-MS). Enzymatic hydrolysis performed for 21 h yielded 100% degree of hydrolysis for all glycosides but citronellyl (97%). Degree of acid hydrolysis was highly dependent on type of aglycone and the conditions. The highest degree was achieved for geraniol, followed by citronellol and nerol. Myrtenylo-ß-D-glycopyranoside was the most resistant glycoside to hydrolysis. Acid hydrolysis degree was also related to temperature/time combination, the highest being for 100 °C and 2 h. In a result of enzymatic hydrolysis 85-91% of total peak areas was terpene aglycone, whereas for acid hydrolysis the area of released terpene aglycone did not exceed 1.3% of total peak area indicating almost complete decomposition/transformation of terpenyl aglycone.


Asunto(s)
Aromatizantes/análisis , Vitis/química , Monoterpenos Acíclicos , Glicósidos/química , Hidrólisis , Monoterpenos/química , Terpenos/química
13.
Food Chem ; 188: 459-66, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26041218

RESUMEN

Two new commercially available high linolenic oils, pressed at low temperature from rose hip seeds, were characterised for their composition, quality and DPPH radical scavenging activity. The oxidative stability of oils was assessed using differential scanning calorimetry (DSC). Phytosterols, tocopherols and carotenoids contents were up to 6485.4; 1124.7; and 107.7 mg/kg, respectively. Phenolic compounds determined for the first time in rose hip oil totalled up to 783.55 µg/kg, with a predominant presence of p-coumaric acid methyl ester. Antiradical activity of the oils reached up to 3.00 mM/kg TEAC. The acid, peroxide and p-anisidine values as well as iron and copper contents indicated good quality of the oils. Relatively high protection against oxidative stress in the oils seemed to be a result of their high antioxidant capacity and the level of unsaturation of fatty acids.


Asunto(s)
Antioxidantes/análisis , Rastreo Diferencial de Calorimetría/métodos , Aceites de Plantas/análisis , Aceites de Plantas/química , Rosa/química , Compuestos de Bifenilo/química , Carotenoides/análisis , Frío , Ácidos Grasos/análisis , Oxidación-Reducción , Fenoles/análisis , Fitosteroles/análisis , Picratos/química , Aceites de Plantas/normas , Presión , Semillas/química , Tocoferoles/análisis
14.
J Chromatogr A ; 1313: 185-93, 2013 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-23932370

RESUMEN

Three approaches in determination of six haloanisoles (2,4,6-trichloroanisole, 2,3,4-trichloroanisole, 2,3,6-trichloroanisole, tetrachloroanisole, pentachloroanisole and 2,4,6-tribromoanisole) in wine were compared. Comprehensive gas chromatography - time of flight mass spectrometry (GC×GC-ToF-MS) was described for the first time for this application and compared to gas chromatography-tandem mass spectrometry (GC-MS/MS) using triple quadrupole instrument. These techniques were compared with "standard" analytical approach using GC-MS(SIM). SPME method was developed and used for all separation methods (DVB/PDMS fiber, 70 °C, 30%NaCl, 20 min extraction). Extraction dependence on matrix was discussed using model wines with different ethanol contents (8%, 12%, and 18%) as well as water and different wines (dry white, dry red and sweet liqueur), with the lowest sensitivities obtained for highest ethanol contents in model wine and for liqueur wine. Limits of detection for GC×GC-ToF-MS method were 0.09-2.92 ng/L depending on the examined compound and matrix (compared to 0.1-13.3 ng/L obtained using GC/MS(SIM)). For GC-MS/MS method lower detection limits were achieved than for the GC×GC method (0.01-0.1 ng/L), however comprehensive gas chromatography-mass spectrometry provides full spectral information on analyzed compounds. Both methods had limits of detection far below odor thresholds of haloanisoles in wine, good linearity up to 2000 ng/L tested and good precision, what makes them suitable for analysis of these compounds in low ppt levels.


Asunto(s)
Anisoles/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Sólida/métodos , Vino/análisis , Límite de Detección , Reproducibilidad de los Resultados
15.
J Agric Food Chem ; 61(11): 2648-54, 2013 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-23414530

RESUMEN

Cereal coffee is a coffee substitute made mainly from roasted cereals such as barley and rye (60-70%), chicory (15-20%), and sugar beets (6-10%). It is perceived by consumers as a healthy, caffeine free, non-irritating beverage suitable for those who cannot drink regular coffee made from coffee beans. In presented studies, typical Polish cereal coffee brew has been subjected to the key odorants analysis with the application of gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). In the analyzed cereal coffee extract, 30 aroma-active volatiles have been identified with FD factors ranging from 16 to 4096. This approach was also used for characterization of key odorants in ingredients used for the cereal coffee production. Comparing the main odors detected in GC-O analysis of roasted cereals brew to the odor notes of cereal coffee brew, it was evident that the aroma of cereal coffee brew is mainly influenced by roasted barley. Flavor compound identification and quantitation has been performed with application of comprehensive multidimentional gas chromatography and time-of-flight mass spectrometry (GCxGC-ToFMS). The results of the quantitative measurements followed by calculation of the odor activity values (OAV) revealed 17 aroma active compounds of the cereal coffee brew with OAV ranging from 12.5 and 2000. The most potent odorant was 2-furfurylthiol followed by the 3-mercapto-3-methylbutyl formate, 3-isobutyl-2-methoxypyrazine and 2-ethyl-3,5-dimethylpyrazine, 2-thenylthiol, 2,3-butanedione, 2-methoxy phenol and 2-methoxy-4-vinyl phenol, 3(sec-butyl)-2-methoxypyrazine, 2-acetyl-1-pyrroline, 3-(methylthio)-propanal, 2,3-pentanedione, 4-hydroxy-2,5-dimethyl-3-(2H)-furanone, (E,E)-2,4-decadienal, (Z)-4-heptenal, phenylacetaldehyde, and 1-octen-3-one.


Asunto(s)
Bebidas/análisis , Grano Comestible/química , Compuestos Orgánicos Volátiles/química , Culinaria , Cromatografía de Gases y Espectrometría de Masas , Humanos , Odorantes/análisis , Olfatometría , Gusto
16.
Anal Chim Acta ; 738: 13-26, 2012 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-22790695

RESUMEN

Food flavor compounds due to the complexity of food as a matrix, and usually their very low concentrations in a product, as well as their low odor thresholds, create a challenge in their extraction, separation and quantitation. Food flavor volatiles represent compounds of different polarity, volatility and chemical character, which determine method of extraction for their isolation from food. Microextraction techniques, mainly SPME and SBSE have been used for food flavor compounds analysis for two decades. Microextraction methods other than SPME and SBSE are seldom used despite their analytical potential. The review discusses the nature of food flavor compounds, and different approaches to food flavor analysis. It summarizes the use of microextraction methods in food flavor compounds analysis based on papers published in the last 5years, and discusses the potential of microextraction methods in this field.


Asunto(s)
Aromatizantes/análisis , Microextracción en Fase Sólida/métodos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Microextracción en Fase Líquida/métodos , Microextracción en Fase Sólida/tendencias , Volatilización
17.
Bioresour Technol ; 111: 328-35, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22366606

RESUMEN

Bacterial utilization of rhamnolipids during biosurfactant-supplemented biodegradation of diesel and B20 (20% biodiesel and 80% diesel v/v) fuels was evaluated under conditions with full aeration or with nitrate and nitrite as electron acceptors. Rhamnolipid-induced changes in community dynamics were assessed by employing real-time PCR and the ddCt method for relative quantification. The experiments with rhamnolipids at 150 mg/l, approx. double critical micelle concentration (CMC) and diesel oil confirmed that rhamnolipids were readily degraded by a soil-isolated consortium of hydrocarbon degraders in all samples, under both aerobic and nitrate-reducing conditions. The presence of rhamnolipids increased the dissipation rates for B20 constituents under aerobic conditions, but did not influence the biodegradation rate of pure diesel. No effect was observed under nitrate-reducing conditions. The biodegradation of rhamnolipids did not favor the growth of any specific consortium member, which proved that the employed biosurfactant did not interfere with the microbial equilibrium during diesel/biodiesel biodegradation.


Asunto(s)
Gasolina , Metabolismo de los Lípidos , Tensoactivos/metabolismo , Biodegradación Ambiental , Reacción en Cadena en Tiempo Real de la Polimerasa
18.
J Chromatogr A ; 1218(42): 7566-73, 2011 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-21831389

RESUMEN

Jutrzenka is a sweet liquer wine produced in Poland from the grape variety of the same name, developed in Poland to withstand the harsh climate of winery regions. Jutrzenka wine has a characteristic aroma with strong fruity and flowery notes, which make it unique among other liquer wines as demonstrated in sensory profile analysis. The work was aimed at characterization of volatile compounds in this wine, with the emphasis on characterization of compounds responsible for its unique aroma. Gas chromatography-olfactometry (GC-O) was applied to identify the key odorants using aroma extract dilution analysis (AEDA) approach. To facilitate free and bound terpenes and C(13)-norisoprenoids identification solid phase extraction (SPE) was used followed by GC/MS. Among identified key odorants ß-damascenone was the compound having the highest FD (4096), followed by isoamyl alcohol, 4-mercapto-4-methyl-2-pentanone (FD=2048), methional, linalool, ethyl decanoate (FD=1024) and ethyl hexanoate, furaneol (FD=512). Other significant compounds were ethyl 2-methyl propanoate, ethyl 2-methylbutanoate and phenyl ethyl alcohol. Determination of odor activity values (OAV) showed the highest values for ß-damascenone (566), 4-mercapto-4-methyl-2-pentanone (288) ethyl hexanoate (32) and linalool (7). Jutrzenka exhibited also a rich profile of free, and to lesser extent bound terpenes.


Asunto(s)
Odorantes/análisis , Compuestos Orgánicos Volátiles/análisis , Vino/análisis , Cromatografía de Gases y Espectrometría de Masas , Norisoprenoides , Polonia , Análisis de Componente Principal , Extracción en Fase Sólida , Terpenos
19.
Anal Chim Acta ; 699(1): 66-72, 2011 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-21704759

RESUMEN

A comparison of SPE cartridges produced in authors laboratory containing silica modified by addition of three functional moieties with standard C-18 and SDVB cartridges was made in terms of their applicability for the isolation of flavor compounds. Compounds found in wine and grapes were used for model mixture, which was spiked into a grape juice. Functionalized phases for SPE were prepared modifying silica gel with alkoxysilanes with different functional groups: (3-(phenylamino)-propyltrimethoxysilane, octyltriethoxysilane and octadecyl-silane. The functionalization was carried out by the dry method, which resulted 5, 10 and 20 weight parts of initial support. Functionalized phases were characterized using FT-IR, elemental analysis and NMR. Performance for new phases compared to "standard" ones (C-18 and SDVB (styrene-divinylbenzene) varied, depending on the group or type of analyzed compound. They were more efficient in extraction of methyl anthranilate and vanilins. For extraction of terpenes, C-6 alcohols, isoprenoids, benzene derivatives and phenols their efficiency was comparable to that of C-18. Functionalized laboratory-made mixed phases are suitable for extraction of flavor compounds from grape juice. They are suitable for extraction of compounds belonging to different chemical classes with the efficiency comparable to C-18 and SDVB phases. The production of such functionalized phases can be easily performed in the laboratory, at a very low cost, comparing to C-18 or SDVB cartridges. This makes the proposed functionalized phases an interesting alternative, in sample preparation for analysis and particularly in preparative/flash chromatography.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Gel de Sílice/química , Estireno/química , Compuestos de Vinilo/química , Compuestos Orgánicos Volátiles/análisis , Adsorción , Extracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/aislamiento & purificación , Vino/análisis
20.
Acta Sci Pol Technol Aliment ; 10(1): 7-17, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22232525

RESUMEN

BACKGROUND: Amount of monoterpene alcohol and their glycoside precursors in grapes is determined by the type of grapes, and the availability of specific hydrolytic enzymes during the manufacturing process. Addition of these enzymes, hydrolysing ß-glycosidic bond, to the grape can be used to increase the potential of aromatic raw material, releasing odoriferous aglycons from non-volatile glycosides and in consequence to enhance the flavour of white wines. In this study complex enzyme preparations AR2000 and Rapidase X-Press were used as a supplement to the musts. MATERIAL AND METHODS: Two white grape varieties (Nachodka and Perla Zali) grown in Golesz vineyard in Jaslo were used for winemaking. Aglycone analysis was conducted on the basis of fast acid hydrolysis and solid phase extraction (SPE-C18) with subsequent GC-MS analysis. Wines treated with enzymes and without enzyme treatment were prepared. Dominating terpenes (linalool, nerol, geraniol, ß-citronelol, α-terpineol) were quantified in this study. RESULTS: Amount of free terpenes was comparable in musts of both varieties (42.7 µg/L for Perla Zali, 46.3 µg/L for Nachodka), however Nachodka had 228.9 µg/L of bound terpenes, compared to 88.8 µg/L in Perla Zali. Addition of glycosidases to musts resulted in an approximately 50 µg/L increase in investigated monoterpenes in Perla Zali and appr. 100 µg/L in Nachodka. Total amount of monoterpenes decreased after 6 months storage, however their levels in enzyme treated wines were significantly higher than in control samples. Enzyme treated wines were evaluated by sensory panel and perceived different from control samples with more pronounced selected notes mainly fruity and floral. CONCLUSION: Addition of enzymes can be used to improve the flavour of white wines produced from the average quality of raw material, influencing the increase in aromatic terpene alcohols. However, one must keep in mind that the changes in amount of released flavour compounds caused by the addition of enzymes may not always have a positive effect.


Asunto(s)
Ciclohexenos/análisis , Glicósido Hidrolasas/metabolismo , Monoterpenos/análisis , Extracción en Fase Sólida/métodos , Terpenos/análisis , Monoterpenos Acíclicos , Monoterpenos Ciclohexánicos , Frutas/química , Cromatografía de Gases y Espectrometría de Masas , Glicósidos/química , Hidrólisis , Polonia , Gusto , Vitis/química , Vino/análisis
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