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1.
J Chromatogr A ; 1626: 461369, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797848

RESUMO

Pumped sorbent tube sampling is a well established method for the sampling of volatile organic compounds (VOCs) and semi volatile organic compounds (SVOCs) in ambient, indoor and workplace atmospheres1. Safe sampling volumes and breakthrough volumes have been published for commonly found VOCs on widely used sorbents such as Tenax, however for newer sorbents and less commonly found VOCs there is less robust data. The Safe Sampling Volumes (SSVs) were determined from 15 tests of Retention Volume on 12 VOCs across the 3 sorbents. VOCs tested were: Aldehydes (C5, C6, C8, C9), Ketones (C4, C6), Alcohols (C3, C4), Furan, Limonene, Isoprene and Ethyl Acetate. 12 VOC / sorbent combinations gave SSVs large enough for practical sampling of indoor atmospheres, while SSVs for Furan on Carbopack-X, Isovaleraldehyde on Tenax TA and Methyl Ethyl Ketone on Tenax TA gave SSVs that were too small to be of practical use. This work identifies suitable sorbents and sampling volumes for the complete range of species tested.


Assuntos
Cromatografia Gasosa/métodos , Polímeros/química , Compostos Orgânicos Voláteis/análise , Adsorção , Poluição do Ar em Ambientes Fechados/análise , Aldeídos/química , Monitoramento Ambiental , Furanos/química , Compostos Orgânicos Voláteis/química
2.
J Breath Res ; 14(4): 046008, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32604084

RESUMO

Sampling of volatile organic compounds (VOCs) has shown promise for detection of a range of diseases but results have proved hard to replicate due to a lack of standardization. In this work we introduce the 'Peppermint Initiative'. The initiative seeks to disseminate a standardized experiment that allows comparison of breath sampling and data analysis methods. Further, it seeks to share a set of benchmark values for the measurement of VOCs in breath. Pilot data are presented to illustrate the standardized approach to the interpretation of results obtained from the Peppermint experiment. This pilot study was conducted to determine the washout profile of peppermint compounds in breath, identify appropriate sampling time points, and formalise the data analysis. Five and ten participants were recruited to undertake a standardized intervention by ingesting a peppermint oil capsule that engenders a predictable and controlled change in the VOC profile in exhaled breath. After collecting a pre-ingestion breath sample, five further samples are taken at 2, 4, 6, 8, and 10 h after ingestion. Samples were analysed using ion mobility spectrometry coupled to multi-capillary column and thermal desorption gas chromatography mass spectrometry. A regression analysis of the washout data was used to determine sampling times for the final peppermint protocol, and the time for the compound measurement to return to baseline levels was selected as a benchmark value. A measure of the quality of the data generated from a given technique is proposed by comparing data fidelity. This study protocol has been used for all subsequent measurements by the Peppermint Consortium (16 partners from seven countries). So far 1200 breath samples from 200 participants using a range of sampling and analytical techniques have been collected. The data from the consortium will be disseminated in subsequent technical notes focussing on results from individual platforms.


Assuntos
Testes Respiratórios/métodos , Mentha piperita/química , Compostos Orgânicos Voláteis/química , Benchmarking , Feminino , Humanos , Masculino
3.
Science ; 368(6497): 1377-1381, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32554595

RESUMO

Plants emit an extraordinary diversity of chemicals that provide information about their identity and mediate their interactions with insects. However, most studies of this have focused on a few model species in controlled environments, limiting our capacity to understand plant-insect chemical communication in ecological communities. Here, by integrating information theory with ecological and evolutionary theories, we show that a stable information structure of plant volatile organic compounds (VOCs) can emerge from a conflicting information process between plants and herbivores. We corroborate this information "arms race" theory with field data recording plant-VOC associations and plant-herbivore interactions in a tropical dry forest. We reveal that plant VOC redundancy and herbivore specialization can be explained by a conflicting information transfer. Information-based communication approaches can increase our understanding of species interactions across trophic levels.


Assuntos
Biota , Cadeia Alimentar , Herbivoria , Insetos/fisiologia , Plantas/parasitologia , Compostos Orgânicos Voláteis/química , Animais , Insetos/química , Plantas/química
4.
Chemosphere ; 258: 127286, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32544811

RESUMO

Micro-capillary bioreactors (1 mm ID, 10 cm long) were investigated for the biodegradation of toluene vapors as a model volatile organic compound (VOC). The intended application is the removal of VOCs from indoor air, when such microbioreactor is coupled with a microconcentrator that intermittently delivers high concentrations of VOCs to the bioreactor for effective treatment. The effects of key operating conditions were investigated. Specifically, gas film and liquid film mass transfer coefficients were determined for different gas and liquid velocities. Both mass transfer coefficients increased with gas or liquid velocity, respectively, and the overall gas-liquid mass transfer was dominated by the liquid-side resistance. Experiments with the microbioreactors focused on the effects of gas velocity, liquid velocity and mineral medium renewal rate on the treatment of toluene vapors at different inlet concentrations. The best performance in terms of toluene removal and mineralization to CO2 was obtained when the gas and liquid velocity ratio was close to one and achieving Taylor or slug flow pattern. Sustained treatment over extended periods of time with toluene elimination capacities ranging from 4000 to over 9000 g m-3 h-1 were obtained, which is orders of magnitude greater than conventional biofilters and biotrickling filters. Biological limitations generally played a more important role than mass transfer limitation. Continuous mineral medium supply at a high rate (10 h liquid retention time) enabled pH control and provided ample nutrient supply and therefore resulted in better toluene elimination and mineralization. Overall, these studies helped select the most suitable conditions for high performance and sustained operation.


Assuntos
Poluentes Atmosféricos/química , Reatores Biológicos , Tolueno/química , Compostos Orgânicos Voláteis/química , Biodegradação Ambiental , Desenho de Equipamento , Gases , Concentração de Íons de Hidrogênio
5.
Food Chem ; 331: 127369, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32590262

RESUMO

To make better use of chicken liver, a byproduct of meat processing with rich proteins, the influence of ultrasound pretreatment on the extent of Maillard reaction (MR) and the properties of MR products (MRPs) of chicken liver protein (CLP) and its hydrolysate (CLPH) were investigated. The extent of MR of sonicated CLPH (SCLPHMs) was significantly higher than that of the other two MRPs. The decreased fluorescence intensity (FI) of the SCLPHMs indicated adequate reaction of d-xylose with sonicated CLPH (SCLPH). The particle size of the three MRPs was significantly larger than that of CLP, CLPH, and SCLPH, respectively. Ultrasound treatment increased the utilization of amino acids and enriched the variety of volatile compounds in all groups. Furfural was the main heterocyclic compound in the MRPs. Therefore, ultrasound pretreatment and enzymolysis of chicken liver may be a foundation for high-value development in flavors for the food industry.


Assuntos
Galinhas , Indústria de Processamento de Alimentos/métodos , Fígado/química , Reação de Maillard , Proteínas de Aves Domésticas/química , Compostos Orgânicos Voláteis/química , Aminoácidos/análise , Aminoácidos/química , Animais , Aromatizantes/química , Produtos Finais de Glicação Avançada/química , Produtos Avícolas , Hidrolisados de Proteína/química , Paladar , Ultrassom , Compostos Orgânicos Voláteis/análise , Xilose/química
6.
Food Chem ; 329: 127181, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32502743

RESUMO

The compounds that the wood releases to the wine and the oxygen transmission rate (OTR) of the barrel define the final wine. The new possibility of choosing the OTR of the barrel allows the winemaker to globally control the ageing process. The aim of this work was to study the volatile composition of woods classified according to their OTR, which are used to build barrels for wine ageing. The results showed that volatile composition differs depending on wood OTR and the temperature reached during toasting. On the toasted side of the stave in contact with the wine, low OTR wood had a statistically higher content in furan compounds (5-hydroxymethylfurfural, furfural and 5-methylfurfural), acetovanillone and phenolic aldehydes (vanillin and syringaldehyde), while 4-ethylguaiacol and trans-ß-methyl-γ-octalactone were significantly higher in staves with a high OTR. The same red wine aged first for three months in high and low oxygenation barrels presents different characteristics.


Assuntos
Manipulação de Alimentos/métodos , Oxigênio/química , Quercus/química , Compostos Orgânicos Voláteis/química , Vinho/análise , Benzaldeídos/química , Cromatografia Gasosa , Análise Discriminante , Furanos/química , Guaiacol/química , Temperatura , Madeira/química
7.
Food Chem ; 331: 127258, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32544652

RESUMO

Flavor stability is important for the quality of tea beverages. Baking is a typical processing technology to improve the flavor of tea leaves. In present study, seven raw tea materials, including steamed spring and autumn tea leaves, pan-fired spring tea leaves, and their corresponding baked tea leaves, were used to investigate the effect of baking on flavor stability of green tea beverages. The results showed that tea beverages prepared with baked tea had better flavor stability. The baking process obviously changed the concentrations of some important flavor substances, especially the aromatic pyrrole substances from 0 (unbaked) to 338.13 µg/L (baked) in tea beverages. Heat treatment had little influence on the flavor of tea beverages prepared from baked tea, but caused great changes in non-volatile and volatile components in those prepared from unbaked leaves. These results could help guide the processing of tea beverages which would improve their flavor quality stability.


Assuntos
Bebidas/análise , Manipulação de Alimentos/métodos , Chá/química , Catequina/análise , Cromatografia Líquida de Alta Pressão , Cor , Espectrometria de Massas , Folhas de Planta/química , Folhas de Planta/metabolismo , Polifenóis/análise , Análise de Componente Principal , Paladar , Chá/metabolismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
8.
Chemosphere ; 255: 126930, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32402878

RESUMO

Emissions of volatile organic compounds (VOCs) air pollutants could worsen air quality and adversely affect human health, thus developing more efficient low-temperature VOCs removal techniques is desired. A novel continuous system integrating UV-assisted photo-electrochemical catalysis with microbial fuel cell (UV-assisted PEC-MFC) has been established for promoting removal of gaseous ethyl acetate or toluene and generating electricity simultaneously. In this system, CeO2/TiO2/ACF catalytic cathode is prepared and used for combination with bio-anode for accelerating cathodic reaction. This UV-assisted PEC-MFC system exhibits an excellent elimination capacity (EC) of ethyl acetate (∼0.39 g/m3, EC: ∼2.52 g/m3/h) or toluene (∼0.29 g/m3, EC: 1.89 g/m3/h) under close-circuit condition. Furthermore, an outstanding elimination capacity (EC: 28.04 g/m3/h) for high concentration toluene (∼4.10 g/m3) removal is obtained after toluene gas passes sequentially through the catalytic cathode then the bio-anode. This way of PEC degradation and biodegradation, avoids inhibition of exoelectrogens activity from toxicity of high concentration toluene. Simultaneously, the cell voltage of UV-assisted PEC-MFC system is stable at 0.11 V (vs. SCE) and 1.452×10-4 kWh is generated from treatment of toluene gas stream in 6 h duration time. The possible mechanism of VOCs removal in this novel system has been proposed and discussed. This study provides new technical basis for treating gaseous pollutants via integrating photo-electrochemical catalysis with electricity generating microbial fuel cell for energy conversion.


Assuntos
Compostos Orgânicos Voláteis/química , Poluentes Atmosféricos/química , Biodegradação Ambiental , Fontes de Energia Bioelétrica , Catálise , Eletricidade , Eletrodos , Poluentes Ambientais , Gases , Titânio , Tolueno/química , Raios Ultravioleta
9.
Chemosphere ; 256: 127054, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32450356

RESUMO

In this work, very efficient VOCs adsorbent was developed from waste bovine bone. After pyrolysis at 450 °C, the bone char was treated by H3PO4 for surface modification and activated by K2CO3 respectively. The prepared materials were characterized by N2 adsorption isotherms, SEM, FT-IR, and XPS. Adsorption/desorption and regeneration behavior of VOCs were also studied. Results showed that H3PO4 modification can effectively accelerate the adsorption process and after K2CO3 activation, a new hierarchical pore structure was found with an ultrahigh total pore volume of 2.807 cm3/g. The specific adsorption capacity for typical VOC reached ∼13.03 mmol/g which is much higher than literature data under the same condition. Static toluene adsorption test on the prepared activated bone-char revealed that the hierarchical structure has provided abundant adsorption sites and the adsorption behavior can be well described by the pseudo-second-order model. The dynamic/static adsorption ratio increased from 70.31% to 78.62% due to less mass transfer resistance by surface modification.


Assuntos
Carvão Vegetal/química , Compostos Orgânicos Voláteis/química , Adsorção , Animais , Osso e Ossos/química , Bovinos , Pirólise , Espectroscopia de Infravermelho com Transformada de Fourier , Tolueno/química
10.
J Food Sci ; 85(6): 1764-1771, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32406938

RESUMO

The novel discovery of p-hydroxyphenylbutan-2-one (berry note) in Riceberry aroma was characterized by gas chromatography-olfactometry and gas chromatography-time-of-flight mass spectrometry. Odor activity values and aroma extract dilution analysis revealed the high potency of this ketone, vanillin, and guaiacol found within the purple rice. Furthermore, ultrapasteurization (UP), high-temperature short-time (HTST) pasteurization, and ultrahigh-temperature (UHT) sterilization effects on rice beverage aroma were analyzed using Riceberry as a sample. Riceberry's key odorants also remained the primary aromatic contributors in beverage models. Although descriptive sensory analysis showed a slightly lower musty note intensity in HTST beverages compared to the UP sample, their flavor dilution chromatograms were similar. Cluster analysis and R-index ranking test further confirmed aroma similarities during storage. Stored samples sterilized via UHT experienced certain potential off-odors, including acetic acid, propanoic acid, and indole, as opposed to the other beverages. UP was therefore superior to HTST and UHT by extending beverage shelf life without any undesirable odors. PRACTICAL APPLICATION: Ultrapasteurization (UP) retains Riceberry aroma characteristic in beverages and requires minimal modifications beyond conventional pasteurization. UP beverages also surpass those of high-temperature short-time and ultrahigh-temperature by extending shelf life with no noticeable off-odors. In addition, the discovery of p-hydroxyphenylbutan-2-one and the other aroma-active compounds of Riceberry aroma should prove valuable for flavor creation, rice breeding, and rice quality standards.


Assuntos
Bebidas/análise , Sucos de Frutas e Vegetais/análise , Oryza/química , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Humanos , Odorantes/análise , Olfatometria , Pasteurização , Paladar , Temperatura , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
11.
Food Chem ; 322: 126754, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283367

RESUMO

During storage of coffee, the key aroma 2-furfurylthiol becomes less active, the mechanisms of this loss and ways to mitigate it were investigated. Aroma profiles were analyzed using GC-MS and sensory properties were evaluated by Quantitative Descriptive Analysis. Quinones, as the oxidation products of hydroxydroquinone, was found to actively bind 2-furfurylthiol, which accounted for the loss of 2-furfurylthiol. To mitigate this loss, ingredients were screened for their ability to prevent 2-furfurylthiol from loss. Cysteine had the highest 2-furfurylthiol releasing efficiency and ascorbic acid was also selected due to its 2-furfurylthiol releasing ability in Fenton reaction system. Concentrations were optimized and the addition of 0.045 g/L cysteine and 0.05 g/L ascorbic acid directly protected aroma during storage, these included 2-furfurylthiol, dimethyltrisulfide, methyl furfuryl disulfide, 4-ethylguaiacol and 4-vinylguaiacol. Ultimately, sensory testing showed a direct enhancement in nutty, sulfurous and roasted aroma attributes, an increase in flavour intensity and preference over shelf life.


Assuntos
Café/química , Furanos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Compostos de Sulfidrila/metabolismo , Compostos Orgânicos Voláteis/análise , Ácido Ascórbico/química , Café/metabolismo , Culinária/métodos , Cisteína/química , Armazenamento de Alimentos , Furanos/química , Análise dos Mínimos Quadrados , Quinonas/química , Quinonas/metabolismo , Compostos de Sulfidrila/química , Paladar , Compostos Orgânicos Voláteis/química
12.
Food Chem ; 322: 126779, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32305877

RESUMO

The transfer kinetics of three labelled compounds (butanal, 2-phenyethanol, isoamyl acetate) was studied from a liquid medium into the coffee beans during simulated wet processing using four media (M) (M1: contained dehulled beans, M2: contained demucilaginated beans, M3: contained depulped beans, M4: contained depulped beans with yeast). Trials were carried out at 25 °C, under agitation and for five time periods (0, 6, 12, 24 and 48 h), and then the labelled volatiles were analyzed by SPME-GC-MS. The three labelled molecules were transferred into the coffee beans with different mass transfer rates; reaching at 12hrs in the M4, 0.2 ± 0.03, 11.2 ± 0.66 and 1.3 ± 0.04 µg/g of coffee respectively for butanal, 2-phenyethanol and isoamyl acetate. The parchment resistance significantly affected the mass transfer of the 2-phenylethanol. Butanal and isoamyl acetate underwent metabolic reactions, which decreased their amount in the coffee beans. Furthermore, an interaction between molecules and the yeast was observed and decreased significantly the butanal's transfer.


Assuntos
Café/química , Indústria de Processamento de Alimentos/métodos , Odorantes/análise , Saccharomyces cerevisiae/metabolismo , Compostos Orgânicos Voláteis/química , Aldeídos/análise , Coffea/química , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Pentanóis/análise , Pentanóis/química , Álcool Feniletílico/análise , Álcool Feniletílico/química , Sementes/química , Compostos Orgânicos Voláteis/análise
13.
Environ Monit Assess ; 192(5): 280, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32281026

RESUMO

In this study, benzene was selected as an indicator of VOCs, and a modeling procedure was carried out on benzene removal (outflow concentration of benzene, C/inflow concentration of benzene, C0), in DC and AC non-thermal plasma systems. Different diameters (18, 23, and 36 mm) of wire-tube plasma reactors were prepared, and models were raised based on the results of experiments with influencing factors of the used voltage, gap size inside the reactor, current density, and specific energy. The results showed correlation between the factors and benzene removal in both DC and AC discharge non-thermal plasma. The applied voltage as an electrical factor had negative correlation with C/C0, and the correlation was stronger than for gap size which was positively correlated with C/C0. Current density and specific energy were affected by the voltage and gap size of the reactor; the lowest C/C0 values were obtained in the highest values of specific energy and current density. Regarding the raised models, multi-factor exponential model was the most reliable one with the results.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Modelos Químicos , Compostos Orgânicos Voláteis/química , Benzeno , Técnicas Eletroquímicas
14.
BMC Complement Med Ther ; 20(1): 109, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32276586

RESUMO

BACKGROUND: Ligularia fischeri (Ledeb) Turcz (LFT) is a well-known expectorant and active anti-inflammatory agent in Chinese traditional medicine. LFT's expectorant effect is closely related to its anti-inflammatory effects. This study aimed to evaluate the differential composition and anti-inflammatory mechanisms of the volatile components in LFT from different production areas. METHOD: Headspace solid-phase microextraction-gas chromatography-mass spectrometry analysis of volatile components, as well as chemometric methods, including similarity analysis, hierarchical clustering analysis, and principal component analysis, were performed to identify LFT produced in different areas. The molecular mechanism underlying the anti-inflammatory effects of these components was determined by network pharmacology analysis. RESULTS: We observed significant differences in the chemical constituents and percentage contents in samples with different origins. Eighteen volatile components were identified in four different producing areas, among which the highest content of olefinic components was the main component of the aroma of LFT. The mechanisms of these pharmacological effects involved multiple targets and pathways. Twenty-seven potential target proteins and 65 signaling pathways were screened, and a "component-target-disease" interaction network map was constructed. The volatile components of the LFT function mainly by inhibiting the production of inflammatory factors. CONCLUSION: This study provides a theoretical framework for further development and application of LFT used in traditional Chinese medicine.


Assuntos
Anti-Inflamatórios/farmacologia , Ligularia/química , Extratos Vegetais/farmacologia , Compostos Orgânicos Voláteis/farmacologia , Anti-Inflamatórios/química , China , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Mapas de Interação de Proteínas , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/química
15.
Chemosphere ; 251: 126358, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32155493

RESUMO

Acidic substances, which produced during chlorinated volatile organic compounds, will corrode the commonly used packing materials, and then affect the removal performance of biofiltration. In this study, three biofilters with different filter bed structure were established to treat gaseous chlorobenzene. CaCO3 and 3D matrix material was added in filter bed as pH buffering material and filter bed supporting material, respectively. A comprehensive investigation of removal performance, biomass accumulation, microbial community, filter bed height, voidage, pressure drops, and specific surface area of the three biofilters was compared. The biofilter with CaCO3 and 3D matrix material addition presented stable removal performance and microbial community, and greater biomass density (209.9 kg biomass/m3 filter bed) and growth rate (0.033 d-1) were obtained by using logistic equation. After 200 days operation, the height, voidage, pressure drop, specific surface area of the filter bed consisted of perlite was 27.4 cm, 0.39, 32.8 Pa/m, 974,89 m2/m3, while those of the filter bed with CaCO3 addition was 28.2 cm, 0.43, 21.3 Pa/m, and 1021.03 m2/m3, and those of the filter bed with CaCO3 and 3D matrix material addition was 28.7 cm, 0.55, 17.4 Pa/m, and 1041.60 m2/m3. All the results verified the biofilter with CaCO3 and 3D matrix material addition is capable of sustaining the long-term performance of biofilters. CaCO3 could limit the changes of removal efficiency, microbial community and filter bed structure by buffering the pH variation. And 3D matrix material could maintain the filter bed structure by supporting the filter bed, regardless of the buffering effect.


Assuntos
Clorobenzenos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Óxido de Alumínio , Biomassa , Filtração/métodos , Gases , Concentração de Íons de Hidrogênio , Dióxido de Silício , Compostos Orgânicos Voláteis/química
16.
Chemosphere ; 250: 126338, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32126329

RESUMO

Chlorinated volatile organic compounds (Cl-VOCs) waste air is a kind of typical recalcitrant organic compounds, which poses a great threat to the ecological environment and human health. At present, the biotechnology is considered as a potential strategy for the Cl-VOCs removal due to the advantages of low energy consumption and less possibility of secondary pollution. This work summarizes the recent researches on strains, bioreactors and technology integration. The dominant pure strains for biodegradation of Cl-VOCs are first outlined with a special focus on the co-metabolism of multi-components. It then summarizes two bioreactors (optimized airlift reactor (ALR) and two-phase partitioning bioreactor (TPPB)) and strategy (addition of surfactant) for improvement of biotrickling filter (BTF), which are benefit to achieve the mass transfer enhancement in the removal of hydrophobic Cl-VOCs from waste air. After that, the integration technologies, such as magnetic field (MF)-BTF, non-thermal plasma (NTP)/ultraviolet light (UV)-BTF, and microbial electrolytic cells (MEC), are elucidated, which provide opportunities for complete mineralization of Cl-VOCs in a more efficient, energy-saving and economical way. Finally, current challenges and a perspective of future research on biotechnology for Cl-VOCs removal are thoroughly discussed.


Assuntos
Poluentes Atmosféricos/química , Biodegradação Ambiental , Compostos Orgânicos Voláteis/química , Reatores Biológicos , Biotecnologia , Filtração , Humanos
17.
Microbiol Res ; 236: 126436, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32179388

RESUMO

Trichoderma longibrachiatum EF5 is an endophytic fungal antagonist of rice. It is used for the control of soil-borne fungal pathogens-Sclerotium rolfsii and Macrophomina phaseolina. We demonstrate that T. longibrachiatum EF5 inhibits the growth of these pathogens on direct interaction as well as via the production of the microbial volatile organic compounds (mVOCs). The mVOCs reduced mycelial growth and inhibited the production of sclerotia by altering the mycelial structure. We profiled 138 mVOCs, when T. longibrachiatum EF5 interacted with the two pathogens. During these interactions, several compounds are up- or downregulated by T. longibrachiatum EF5, including longifolene, caryophyllene,1-Butanol 2-methyl, cedrene, and cuprenene. These compounds are involved in the biosynthetic pathways of the sesquiterpenoid and alkane, and the degradation pathway of trimethylamine. We provide an insight into the multiple modes by which T. longibrachiatum EF5 exerts antagonistic actions, such as hyperparasitism, competitions, and antibiosis via mVOCs. In contrast to their antimicrobial properties, these metabolites could also promote plant growth.


Assuntos
Agaricales/efeitos dos fármacos , Antibiose , Ascomicetos/efeitos dos fármacos , Trichoderma/metabolismo , Compostos Orgânicos Voláteis/farmacologia , Agaricales/crescimento & desenvolvimento , Ascomicetos/crescimento & desenvolvimento , Agentes de Controle Biológico , Interações Microbianas , Doenças das Plantas/microbiologia , Microbiologia do Solo , Compostos Orgânicos Voláteis/química
18.
Chemosphere ; 252: 126490, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32220715

RESUMO

Hydrophilic VOCs (volatile organic compounds) were applied to explore their positive influence on the elimination of the single hydrophobic VOC in biotrickling filters (BTFs). Comparison experiments were carried to evaluate the effect of 4-methyl-2-pentanone and toluene on the performance of BTFs for n-hexane removal. The results showed that the existence of 4-methyl-2-pentanone improved the removal performance of BTFs at short gas empty bed contact time (EBRT) of 15 s and low temperature of 10 °C. The degradation of n-hexane in the presence of 4-methyl-2-pentanone was slightly enhanced with a loading ratio of 6:1. When the mixing ratio was greater than 4, toluene significantly promoted the biodegradation of n-hexane with toluene loading rate less than 10 g m-3 h-1. Additionally, The promotion effect was not only reflected in the contents of proteins and polysaccharides, but also in the growth rates of microorganisms in biofilms. This work discussed the detailed effect between n-hexane and hydrophilic VOCs in BTFs, which would contribute to develop a more economical method to improve the removal performance of hydrophobic VOCs in BTFs.


Assuntos
Poluentes Atmosféricos/química , Reatores Biológicos , Hexanos/química , Compostos Orgânicos Voláteis/química , Poluentes Atmosféricos/análise , Biodegradação Ambiental , Biofilmes , Filtração/métodos , Interações Hidrofóbicas e Hidrofílicas , Metil n-Butil Cetona , Tolueno , Compostos Orgânicos Voláteis/análise
19.
Biosensors (Basel) ; 10(3)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192133

RESUMO

The olfactory receptor neurons of insects and vertebrates are gated by odorant receptor (OR) proteins of which several members have been shown to exhibit remarkable sensitivity and selectivity towards volatile organic compounds of significant importance in the fields of medicine, agriculture and public health. Insect ORs offer intrinsic amplification where a single binding event is transduced into a measurable ionic current. Consequently, insect ORs have great potential as biorecognition elements in many sensor configurations. However, integrating these sensing components onto electronic transducers for the development of biosensors has been marginal due to several drawbacks, including their lipophilic nature, signal transduction mechanism and the limited number of known cognate receptor-ligand pairs. We review the current state of research in this emerging field and highlight the use of a group of indole-sensitive ORs (indolORs) from unexpected sources for the development of biosensors.


Assuntos
Insetos/metabolismo , Receptores Odorantes/análise , Compostos Orgânicos Voláteis/química , Animais , Técnicas Biossensoriais , Proteínas de Insetos/análise , Nanotubos de Carbono/química , Transdutores , Transistores Eletrônicos
20.
ScientificWorldJournal ; 2020: 4182064, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32148465

RESUMO

In the present study, eight plant species belonging to Lamiaceae family were identified as ingredients for herbal teas in the region of Sharri Mountains: Thymus serpyllum, Rosmarinus officinalis, Melissa officinalis, Origanum vulgare, Mentha longifolia, Ocimum basilicum, Teucrium chamaedrys, and Sideritis scardica, respectively. Chemical composition of essential oils obtained from these species was analyzed using GC-MS and GC-FID with the aim of examining their volatile compound profiles, responsible for their respective flavors and fragrance. Principal Component Analysis (PCA) was performed with the aim of grouping plant species under study on the basis of their chemical composition. Experimental data revealed the typical volatile constituent pattern for the Lamiaceae family. Monoterpenes and sesquiterpenes, responsible for flavor and medicinal use of these plants, were the most abundant groups of the volatile constituents. PCA data analysis resulted in the grouping of these analyzed species in four principal clusters.


Assuntos
Lamiaceae/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Plantas Medicinais/química , Chá/química , Península Balcânica , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/química , Óleos Vegetais/química , Compostos Orgânicos Voláteis/química
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