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1.
Food Chem ; 312: 126046, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31911354

RESUMO

The impact of crop level and leaf removal on Istrian Malvasia (Vitis vinifera L.) white wine aroma and phenolic acids composition was studied over two vine-growing seasons. Two crop levels were combined with leaf removal or untreated control in two-factorial design. Crop level showed limited impact on aroma compounds in wine and the concentration of some esters was increased by higher crop level. In contrast, leaf removal increased the concentration of several aroma compounds and especially monoterpenes and esters. The concentration of hydroxycinnamic acids in wine was enhanced only by leaf removal, while no consistent impact of the investigated factors on hydroxybenzoic acids was observed. The obtained results suggest that in cases where environmental conditions are not limiting, increasing the crop level under adequate microclimate in fruit zone has no detrimental effects on white wine aroma and hydroxycinnamic acids composition, potentially leading to economically more sustainable grape production.


Assuntos
Hidroxibenzoatos/análise , Odorantes/análise , Vitis/química , Vinho/análise , Éteres/análise , Frutas/química , Monoterpenos/análise
2.
J Sci Food Agric ; 100(2): 517-526, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31512252

RESUMO

BACKGROUND: Aroma is one of the most important aspects of fruit quality and can reflect the characteristics of different fruits. Aroma-active compounds can usefully be employed to trace the production areas of two citrus cultivars ('Eureka' lemon and 'Huapi' kumquat) and to evaluate their aroma quality. RESULTS: 'Huapi' kumquat peel displayed higher monoterpene and sesquiterpene compound content, whereas 'Eureka' lemon peel exhibited higher monoterpene and monoterpene aldehyde compound content. 'Eureka' lemon peel ('Wanzhou' cultivar) had higher nerol acetate and geraniol acetate compound content. Kumquat peel ('Suichuan' and 'Rongan' cultivars) had higher sesquiterpene content. In addition, 30 and 31 aroma-active compounds were observed in kumquat and lemon, respectively, based on their odor activity values. Principal component analysis (PCA) and hierarchical clustering analysis (HCA) results indicated that classification for production areas based on aroma-active compounds was useful. The selected aroma-active compounds have been checked as aroma quality parameters that could be used with multivariate analysis to establish a model of aroma quality evaluation. Higher aroma quality values from kumquat and lemon were collected from Rongan and Wanzhou cultivars, respectively. CONCLUSION: Aroma-active compounds can be used to discriminate production areas using multivariate statistics. An objective method was established to evaluate the aroma quality of citrus fruits. 'Huapi' kumquat and 'Eureka' lemon, which had the highest aroma quality, was harvested from the Rongan and Wanzhou production areas. This was the first time that the aroma quality of citrus fruits was evaluated using multivariate analysis. © 2019 Society of Chemical Industry.


Assuntos
Citrus/química , Odorantes/análise , Compostos Orgânicos Voláteis/química , Acetatos/análise , Monoterpenos Acíclicos/análise , Aldeídos/análise , Frutas/química , Monoterpenos/análise , Controle de Qualidade , Sesquiterpenos/análise
3.
Int J Mol Sci ; 20(24)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835605

RESUMO

Leaves of C. porrectum are rich in essential oils containing monoterpenes, sesquiterpenes and aromatic compounds, but the molecular mechanism of terpenoid biosynthesis in C. porrectum is still unclear. In this paper, the differences in the contents and compositions of terpenoids among three chemotypes were analyzed using gas chromatography mass spectrometry (GC/MS). Furthermore, the differential expression of gene transcripts in the leaf tissues of the three C. porrectum chemotypes were analyzed through a comparison of full-length transcriptomes and expression profiles. The essential oil of the three C. porrectum chemotypes leaves was mainly composed of monoterpenes. In the full-length transcriptome of C. porrectum, 104,062 transcripts with 306,337,921 total bp, an average length of 2944 bp, and an N50 length of 5449 bp, were obtained and 94025 transcripts were annotated. In the eucalyptol and linalool chemotype, the camphor and eucalyptol chemotype, and the camphor and linalool chemotype comparison groups, 21, 22 and 18 terpene synthase (TPS) unigenes were identified respectively. Three monoterpene synthase genes, CpTPS3, CpTPS5 and CpTPS9, were upregulated in the eucalyptol chemotype compared to the linalool chemotype and camphor chemotype. CpTPS1 was upregulated in the camphor chemotype compared to the linalool chemotype and the eucalyptol chemotype. CpTPS4 was upregulated in the linalool chemotype compared to the camphor chemotype and the eucalyptol chemotype. Different unigenes had different expression levels among the three chemotypes, but the unigene expression levels of the 2-C-methyl-D-erythritol 4phosphate (MEP) pathway were generally higher than those of the mevalonate acid (MVA) pathway. Quantitative reverse transcription PCR(qRT-PCR) further validated these expression levels. The present study provides new clues for the functional exploration of the terpenoid synthesis mechanism and key genes in different chemotypes of C. porrectum.


Assuntos
Vias Biossintéticas , Cinnamomum/genética , Perfilação da Expressão Gênica/métodos , Monoterpenos/análise , Cinnamomum/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica de Plantas , Anotação de Sequência Molecular , Monoterpenos/metabolismo , Óleos Voláteis/análise , Óleos Voláteis/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Sequenciamento Completo do Exoma
4.
Int J Mol Sci ; 21(1)2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861733

RESUMO

The effects of plant inoculation with plant growth-promoting rhizobacteria (PGPR) and those resulting from the exogenous application of salicylic acid (SA) or methyl jasmonte (MeJA) on total phenolic content (TPC) and monoterpenes in Mentha x piperita plants were investigated. Although the PGPR inoculation response has been studied for many plant species, the combination of PGPR and exogenous phytohormones has not been investigated in aromatic plant species. The exogenous application of SA produced an increase in TPC that, in general, was of a similar level when applied alone as when combined with PGPR. This increase in TPC was correlated with an increase in the activity of the enzyme phenylalanine ammonia lyase (PAL). Also, the application of MeJA at different concentrations in combination with inoculation with PGPR produced an increase in TPC, which was more relevant at 4 mM, with a synergism effect being observed. With respect to the main monoterpene concentrations present in peppermint essential oil (EO), it was observed that SA or MeJA application produced a significant increase similar to that of the combination with rhizobacteria. However, when plants were exposed to 2 mM MeJA and inoculated, an important increase was produced in the concentration on menthol, pulegone, linalool, limonene, and menthone concentrations. Rhizobacteria inoculation, the treatment with SA and MeJA, and the combination of both were found to affect the amount of the main monoterpenes present in the EO of M. piperita. For this reason, the expressions of genes related to the biosynthesis of monoterpene were evaluated, with this expression being positively affected by MeJA application and PGPR inoculation, but was not modified by SA application. Our results demonstrate that MeJA or SA application combined with inoculation with PGPR constitutes an advantageous management practice for improving the production of secondary metabolites from M. piperita.


Assuntos
Mentha piperita/crescimento & desenvolvimento , Monoterpenos/análise , Fenóis/análise , Reguladores de Crescimento de Planta/farmacologia , Rhizobiaceae/fisiologia , Acetatos/farmacologia , Ciclopentanos/farmacologia , Sinergismo Farmacológico , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Mentha piperita/química , Mentha piperita/microbiologia , Oxilipinas/farmacologia , Fenilalanina Amônia-Liase/metabolismo , Extratos Vegetais/análise , Proteínas de Plantas/metabolismo , Ácido Salicílico/farmacologia , Metabolismo Secundário/efeitos dos fármacos
5.
Bol. latinoam. Caribe plantas med. aromát ; 18(6): 566-576, nov. 2019. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1102643

RESUMO

This paper reports for the first time volatile compounds, anti-nociceptive and anti-inflammatory activities of essential oils from the leaves of Waltheria indica L. (Stericullaceae) growing in Nigeria. The essential oil was hydro-distilled and characterized by gas chromatography-flame ionization detection (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS) analyses. The anti-inflammatory activity was evaluated on carrageenan induced rat paw edema while the anti-nociceptive test was based on hot plate model. The hydro-distillation afforded 0.41% (dry weight basis) of light green oil. Forty compounds representing 99.8% were identified in the oil. The main constituents of the oil were limonene (34.7%), sabinene (21.2%) and citronellal (9.7%). The anti-nociceptive property of the essential oils statically inhibited edema development (p<0.001) at a dose of 200 and 400 mg/kg independent of time of exposure. However, the 100 mg/kg Waltheria indica essential oils (WIEO) displayed a relatively low inhibition (p<0.01-p>0.5) which declines as exposure time increases. The anti-inflammatory activities shows a steady rate and non-dose dependent activity (p<0.001) up to the 3rd h of inflammation study. Conversely, a sharp reduction at the rate of p<0.5, 0.1 and 0.01 for the 100, 200 and 400 mg/kg WIEO doses respectively. Overall, the results presented sustain and establish the anti-nociceptive and anti-inflammatory properties and justifies the need for further evaluation and development of the essential oils from this plant.


Este artículo informa por primera vez de compuestos volátiles, actividades anti-nociceptivas y antiinflamatorias de aceites esenciales de las hojas de Waltheria indica L. (Stericullaceae) que crecen en Nigeria. El aceite esencial fue hidro-destilado y se caracterizó por cromatografía de gases-detección de ionización de llama (GC-FID) y cromatografía de gases junto con análisis de espectrometría de masas (GC-MS). La actividad antiinflamatoria se evaluó en el edema de pata de rata inducido por carragenano, mientras que la prueba antinociceptiva se basó en el modelo de placa caliente. La destilación hidráulica proporcionó 0,41% (en peso seco) de aceite verde claro. Cuarenta compuestos que representan el 99.8% fueron identificados en el aceite. Los principales componentes del aceite fueron el limoneno (34,7%), el sabineno (21,2%) y el citronelal (9,7%). La propiedad anti-nociceptiva de los aceites esenciales inhibió estáticamente el desarrollo del edema (p<0.001) a una dosis de 200 y 400 mg/kg independientemente del tiempo de exposición. Sin embargo, los aceites esenciales de Waltheria indica de 100 mg/kg (WIEO) mostraron una inhibición relativamente baja (p<0.01-p>0.5) que disminuye a medida que aumenta el tiempo de exposición. Las actividades antiinflamatorias muestran una tasa constante y una actividad no dependiente de la dosis (p<0.001) hasta la tercera hora del estudio de inflamación. Por el contrario, una fuerte reducción a una tasa de p<0.5, 0.1 y 0.01 para las dosis de 100, 200 y 400 mg/kg de WIEO respectivamente. En general, los resultados presentados sostienen y establecen las propiedades anti-nociceptivas y antiinflamatorias y justifican la necesidad de una mayor evaluación y desarrollo de los aceites esenciales de esta planta.


Assuntos
Animais , Masculino , Feminino , Ratos , Óleos Voláteis/farmacologia , Malvaceae/química , Anti-Inflamatórios/farmacologia , Temperatura , Carragenina/toxicidade , Cromatografia Gasosa/métodos , Ratos Wistar , Monoterpenos/análise , Ionização de Chama , Analgésicos/farmacologia , Inflamação/induzido quimicamente
6.
Se Pu ; 37(8): 904-910, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642262

RESUMO

One of the most abundant biological volatile organic compounds (BVOCs) in the atmosphere, monoterpene, is characterized by its short lifetime, low concentration, fast temporal and spatial variations, and wide variety of isomers. In this study, a multi-capillary column (MCC) was combined with high-pressure photoionization time-of-flight mass spectrometry (HPPI-TOF MS) and employed to develop an MCC-HPPI-TOF MS combination instrument as an online two-dimensional gas chromatography-mass spectrometry (GC-MS) method for the rapid qualitative and quantitative analysis of monoterpene isomers. As a result, six monoterpene isomers, α -pinene, ß -pinene, α -terpinene, γ -terpinene, 3-carene, and limonene, were successfully isolated in 180 s with limits of detection (LODs) as low as 6 µg/m3 without sample pre-enrichment. This method was successfully applied to the rapid online analysis of monoterpenes released from the branches and leaves of Cedrus atlantica and Sabina chinensis, which shows the capability and potential application of the method for the online detection of complex sample mixtures in environmental monitoring, process analysis, and other fields.


Assuntos
Monoterpenos/análise , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas
7.
Mar Drugs ; 17(9)2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527497

RESUMO

Macroalgae produce a wide range of monoterpenes as secondary metabolites of mevalonate (MVA) and/or methylerythritol phosphate (MEP) pathway (often including haloperoxidase action). Great biodiversity of macroalgal monoterpenes was reported including acyclic, monocyclic, and bicyclic structures. Halogenated monoterpenes exhibited significant biological activity (e.g., anticancer, antiplasmodial, and insecticidal) that is influenced by the number of present halogens (higher halogen content is preferable, especially bromine) and their position within the monoterpene skeleton. In distinction from the existing reviews, the present review provides novelty with respect to: (a) exclusively monoterpenes from red macroalgae are targeted; (b) biosynthesis, isolation, and analysis, as well as bioactivity of monoterpenes are represented; (c) the methods of their isolation, analysis, and structure elucidation are summarized; (d) the bioactivity of macroalgal monoterpenes is systematically presented with emphasis on anticancer activity; (e) the literature references were updated.


Assuntos
Antineoplásicos/farmacologia , Monoterpenos/farmacologia , Rodófitas/química , Alga Marinha/química , Animais , Antineoplásicos/análise , Antineoplásicos/química , Linhagem Celular Tumoral , Eritritol/análogos & derivados , Eritritol/metabolismo , Humanos , Ácido Mevalônico/metabolismo , Estrutura Molecular , Monoterpenos/análise , Monoterpenos/metabolismo , Rodófitas/metabolismo , Alga Marinha/metabolismo , Fosfatos Açúcares/metabolismo
8.
Molecules ; 24(18)2019 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-31500359

RESUMO

Lavender oil is one of the most valuable aromatherapy oils, its anti-bacterial and anti-fungal activities can be explained by main components such as linalool, linalyl acetate, lavandulol, geraniol, or eucalyptol. The aim of the study was to assess the anti-microbial effects of two different lavender oils on a mixed microbiota from facial skin. The commercial lavender oil and essential lavender oil from the Crimean Peninsula, whose chemical composition and activity are yet to be published, were used. Both oils were analysed by gas chromatography coupled to mass spectrometry. The composition and properties of studied oils were significantly different. The commercial ETJA lavender oil contained 10% more linalool and linalyl acetate than the Crimean lavender oil. Both oils also had different effects on the mixed facial skin microbiota. The Gram-positive bacilli were more sensitive to ETJA lavender oil, and Gram-negative bacilli were more sensitive to Crimean lavender oil. However, neither of the tested oils inhibited the growth of Gram-positive cocci. The tested lavender oils decreased the cell number of the mixed microbiota from facial skin, but ETJA oil showed higher efficiency, probably because it contains higher concentrations of monoterpenoids and monoterpenes than Crimean lavender oil does.


Assuntos
Antibacterianos/farmacologia , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Pele/microbiologia , Monoterpenos Acíclicos/análise , Antibacterianos/química , Face , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Lavandula/química , Testes de Sensibilidade Microbiana , Monoterpenos/análise , Monoterpenos/química , Óleos Voláteis/química , Óleos Vegetais/química
9.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 480-491, sept. 2019. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1008273

RESUMO

In the present study, we investigated the antiproliferative activity of essential oil from leaves of Melissa officinalis L. grown in Southern Bosnia and Herzegovina. In vitro evaluation of antiproliferative activity of the M. officinalis essential oil was carried out on three human tumor cell lines: MCF-7, NCI-H460 and MOLT-4 by MTT assay. M. officinalis essential oil was characterized by high percentage of monoterpenes (77,5%), followed by the sesquiterpene fraction (14,5%) and aliphatic compounds (2,2%). The main constituents of the essential oil of M. officinalis are citral (47,2%), caryophyllene oxide (10,2%), citronellal (5,4%), geraniol (6,6%), geranyl acetate (4,1%) and ß- caryophyllene (3,8%). The essential oil showed significant antiproliferative activity against three cancer cell lines, MOLT-4, MCF-7, and NCI-H460 cells, with GI50 values of <5, 6±2 and 31±17 µg/mL, respectively. The results revealed that M. officinalis L. essential oil has a potential as anticancer therapeutic agent.


En el presente estudio, investigamos la actividad antiproliferativa del aceite esencial de las hojas de Melissa officinalis L. cultivadas en el sur de Bosnia y Herzegovina. La evaluación in vitro de la actividad antiproliferativa del aceite esencial de M. officinalis se llevó a cabo en tres líneas celulares de tumores humanos: MCF-7, NCI-H460 y MOLT-4 utilizando el ensayo de MTT. El aceite esencial de M. officinalis se caracterizó por un alto porcentaje de monoterpenos (77,5%), seguido de la fracción sesquiterpénica (14,5%) y compuestos alifáticos (2,2%). Los principales constituyentes del aceite esencial de M. officinalis fueron citral (47,2%), óxido de cariofileno (10,2%), citronelal (5,4%), geraniol (6,6%), acetato de geranilo (4, 1%), y ß-cariofileno (3,8%). El aceite esencial mostró una actividad antiproliferativa significativa contra las líneas celulares de cáncer MOLT-4, MCF-7 y NCI-H460, con valores GI50 de <5, 6±2 y 31±17 µg/mL, respectivamente. Los resultados revelaron que el aceite esencial de M. officinalis L. tiene potencial como agente terapéutico contra el cáncer.


Assuntos
Óleos Voláteis/farmacologia , Melissa , Antineoplásicos/farmacologia , Sesquiterpenos/análise , Técnicas In Vitro , Óleos Voláteis/química , Células Tumorais Cultivadas , Folhas de Planta , Monoterpenos/análise , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Antineoplásicos/química
10.
Bol. latinoam. Caribe plantas med. aromát ; 18(4): 435-443, jul. 2019. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1008258

RESUMO

Volatiles compounds are involved in defensive induction against insects, playing an important role in insect-plant interaction being induced by response to mechanical damage. However, they could decrease according to the domestication degree in cultivated plants. Currently, it has been established that secondary metabolites are reduced due to the domestication process in murtilla. Hence, the follow question emerges: Are volatile organic compounds induced by mechanical damage reduced in cultivated murtilla plants in relation to wild plants? Two cultivated ecotypes and their respective wild counterparts were sampled. Volatiles compounds were obtained using Porapak-Q columns and analyzed by gas chromatography. Results showed that compounds as 2-hexanone, α-pinene, 2-thujene, 3-thujene and 1,8- cineole were more abundant in wild plants exposed to a mechanical damage than cultivated plants. Hence, these compounds have been associated to induced defense, these results suggest that domestication reduced the induction of defensive volatiles in cultivated murtilla in response to mechanical damage.


Los compuestos volátiles están implicados en la defensa inducida contra insectos, desempeñando un papel importante en esta interacción. Sin embargo, estos compuestos podrían disminuir según el grado de domesticación. Actualmente, se ha reportado que algunos metabolitos secundarios son reducidos en plantas de murtilla domesticadas. Por lo tanto, surge la siguiente pregunta de investigación: ¿Los compuestos orgánicos volátiles inducidos por el daño mecánico son reducidos en plantas cultivadas de murtilla en comparación con plantas silvestres? Para dos ecotipos cultivados y sus respectivas contrapartes silvestres, los compuestos volátiles fueron capturados usando columnas de Porapak-Q y las muestras analizadas por cromatografía gaseosa. Los resultados mostraron que compuestos tales como 2- hexanona, α-pineno, 2-tujeno, 3-tujeno y 1,8-cineol fueron más abundantes en plantas silvestres expuestas a daño mecánico que en cultivadas. Debido a que estos compuestos se han asociado a defensa inducida, estos resultados sugieren que la domesticación reduce la inducción de volátiles en plantas cultivadas sometidas a daño mecánico.


Assuntos
Animais , Óleos Voláteis/metabolismo , Myrtaceae/metabolismo , Myrtaceae/microbiologia , Domesticação , Insetos/fisiologia , Sesquiterpenos/análise , Sesquiterpenos/metabolismo , Óleos Voláteis/química , Myrtaceae/química , Monoterpenos/análise , Monoterpenos/metabolismo , Meio Selvagem , Larva/fisiologia , Cromatografia Gasosa-Espectrometria de Massas
11.
Environ Sci Pollut Res Int ; 26(24): 24988-24997, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31240663

RESUMO

Essential oils (EOs) extracted from leaves (EL) and fruit pericarp (EFP) of Zanthoxylum planispinum var. dintanensis were analyzed for their chemical composition by GC-MS technique and evaluated for their fumigant, contact toxicity and repellency against three stored-product insects, namely Tribolium castaneum, Lasioderma serricorne, and Liposcelis bostrychophila adults. Results of GC-MS analysis manifested that EL and EFP of Z. planispinum var. dintanensis were mainly composed of oxygenated monoterpenes. Major components included linalool, sylvestrene and terpinen-4-ol. The obvious variation observed between two oil samples was that EL contained 2-dodecanone (11.52%) in addition to the above mentioned components, while this constituent was not detected in EFP. Bioassays of insecticidal and repellent activities were performed for EL, EFP as well as some of their individual compounds (linalool, terpinen-4-ol and 2-dodecanone). Testing results indicated that EL, EFP, linalool, terpinen-4-ol and 2-dodecanone exhibited potent insecticidal and repellent activities against the three target insects selected. Among the three individual compounds, 2-dodecanone was significantly toxic to T. castaneum (LD50 = 5.21 µg/adult), L. serricorne (LD50 = 2.54 µg/adult) and L. bostrychophila (LD50 = 23.41 µg/cm2) in contact assays and had beneficial repellent effects on L. serricorne at 2 and 4 h post-exposure. The anti-insect efficacy of Z. planispinum var. dintanensis EO suggests it has potential to be used as botanical insecticide or repellent to control pest damage in warehouses and grain stores.


Assuntos
Repelentes de Insetos/farmacologia , Inseticidas/análise , Monoterpenos/química , Óleos Voláteis/química , Terpenos/química , Zanthoxylum/química , Monoterpenos Acíclicos , Animais , Besouros/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Repelentes de Insetos/química , Inseticidas/química , Dose Letal Mediana , Monoterpenos/análise , Oxirredução , Tribolium/química
12.
Environ Pollut ; 252(Pt A): 493-500, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31163382

RESUMO

Thirteen secondary organic aerosol (SOA) tracers of isoprene, monoterpenes and sesquiterpenes were measured for PM2.5 aerosols collected at the summit of Mt. Wuyi (1139 m, a.s.l.), to investigate their seasonality and formation mechanism. Concentrations of the isoprene and monoterpene SOA tracers were much higher in summer than those in other seasons. In contrast, ß-caryophyllinic acid was found to be the lowest in summer. Concentrations of those BSOA tracers showed a positive correlation with temperature (R2 = 0.52-0.70), and a negative correlation with relative humidity (R2 = 0.43-0.78). Moreover, thermodynamic model (i.e., ISORROPIA-II) calculation results showed that acidity conditions are favorable for BSOA formation. Robust linear correlations between the BSOA tracers and anthropogenic pollutants such as SO2 (R2 = 0.53-0.7) and NO2 (R2 = 0.37-0.54) were observed for all the samples, suggesting that SO2 and NOx can enhance BSOA production in the remote mountain area of southeast China, which is related to an acid-catalyzed heterogeneous chemistry. Moreover, we also found a significant correlation between the concentrations of the BSOA tracers and levoglucosan especially for ß-caryophyllinic acid, indicating that biomass burning plumes from the distant lowland regions could influence the production of BSOA in the mountain free troposphere. Our results clearly demonstrated that anthropogenic emissions in China could enhance BSOA formation in the distant mountain regions.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Butadienos/análise , Monitoramento Ambiental , Hemiterpenos/análise , Monoterpenos/análise , Sesquiterpenos/análise , Biomassa , China , Material Particulado/análise , Estações do Ano
13.
J Food Sci ; 84(7): 1979-1985, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31206673

RESUMO

Essential oils (EO) are widely used in foods as flavoring and preservative agents. Many of the biological activities of EO have been attributed to major essential oil compounds (EOC) but their direct interaction with colonic epithelial cells and their genotoxic and genoprotective effects are not well established. In this study, the cytotoxicity and genotoxicity of EOC including nerolidol, thymol, geraniol, methylisoeugenol, eugenol, linalool, and a commercial blend (Agolin) were determined. Furthermore, the genoprotective effects of EOC against oxidative and methylating damage were assessed using the comet assay in HT-29 colorectal adenocarcinoma cells. The majority of EOC were cytotoxic to HT-29 cells at or above 250 ppm after 24 hr exposure. At noncytotoxic doses, none of the EOC was genotoxic in the comet assay. Genoprotection against oxidative DNA damage was observed for nerolidol (at 62.5 ppm), thymol (at 12.5 ppm), geraniol, and methylisoeugenol (both at 125 ppm), as well as linalool and Agolin (both at 250 ppm). Thymol was the most protective compound against oxidative DNA damage and geraniol (at 125 ppm) also protected cells against methylating DNA damage. This study highlights the potential of EOC such as thymol to protect the colonic epithelium against oxidative DNA damage and geraniol against methylating DNA damage. Further in vivo studies are needed to confirm these findings for safety and efficacy to exploit their potential pharmaceutical or nutraceutical uses for colonic health.


Assuntos
Dano ao DNA/efeitos dos fármacos , Óleos Voláteis/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Monoterpenos Acíclicos , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Ensaio Cometa , Metilação de DNA/efeitos dos fármacos , Eugenol/análise , Eugenol/farmacologia , Humanos , Monoterpenos/análise , Monoterpenos/farmacologia , Óleos Voláteis/análise , Substâncias Protetoras/análise , Terpenos/análise , Terpenos/farmacologia , Timol/análise , Timol/farmacologia
14.
Food Chem ; 295: 72-81, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174812

RESUMO

Grapefruits are sensitive to develop chilling injury (CI) on the peel upon postharvest storage at low temperature. We investigated the influence of the storage at 2 and 12 °C on CI, carotenoids, and emission of volatiles by intact fruit. CI symptoms at 12 °C were restricted to green fruit peel sectors but at 2 °C the CI severity was higher and distributed through the whole fruit surface. Fruit peel coloration and carotenes content increased at 12 °C whereas experienced minor changes at 2 °C. At 2 °C the emission of total volatiles and specific monoterpenes, mainly limonene, but also linalool and α-terpineol was enhanced, while storage at 12 °C resulted in higher emission and diversity of cyclic sesquiterpenes and aliphatic esters. Results indicate a selective emission of volatiles by intact red grapefruit that appears to be a specific response to the storage temperature or to the cold-induced damage.


Assuntos
Carotenoides/análise , Citrus paradisi/química , Armazenamento de Alimentos/métodos , Compostos Orgânicos Voláteis/análise , Monoterpenos Acíclicos , Temperatura Baixa , Monoterpenos Cicloexânicos , Cicloexenos/análise , Cicloexenos/química , Frutas/química , Monoterpenos/análise , Monoterpenos/química , Compostos Orgânicos Voláteis/química
15.
J Sci Food Agric ; 99(12): 5606-5609, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31206173

RESUMO

BACKGROUND: There is a lack of information on the presence of volatile organic compounds including p-cymene in foods for dietary exposure assessment. p-Cymene is a monoterpene found in many plant species, which has been used as a flavouring agent in foods and also exhibits antioxidant and antimicrobial properties. While the Joint FAO/WHO Expert Committee on Food Additives (JECFA) has no safety concerns at current levels of intake when used as a flavouring, the current study examines p-cymene levels in foods in general, not just from possible uses as a flavouring, as there could still be a potential health concern if there were high levels of exposure. RESULTS: 159 food composite samples from the 2014 Canadian Total Diet Study were analysed for p-cymene using a gas chromatographic-mass spectrometric method after headspace solid-phase microextraction. Concentrations of p-cymene in the composite samples of most food types were generally low, with a maximum level of 73.5 µg g-1 , detected in the composite sample of herbs and spices. Dietary exposures to p-cymene were estimated for different age groups of Canadian populations. CONCLUSIONS: Although p-cymene was detected in various foods, estimated dietary exposures to p-cymene for different age groups are well below the human intake threshold of toxicological concern established by JECFA of 1800 µg per person per day for structural class I flavours, which includes p-cymene. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/análise , Exposição Dietética/análise , Monoterpenos/análise , Adolescente , Adulto , Idoso , Animais , Antioxidantes/metabolismo , Canadá , Criança , Pré-Escolar , Cimenos , Grão Comestível/química , Grão Comestível/metabolismo , Fast Foods/análise , Feminino , Aromatizantes/análise , Aromatizantes/metabolismo , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactente , Masculino , Carne/análise , Pessoa de Meia-Idade , Monoterpenos/metabolismo , Verduras/química , Verduras/metabolismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Adulto Jovem
16.
Niger J Clin Pract ; 22(5): 718-726, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31089029

RESUMO

Aims: This work was designed to evaluate the antimicrobial activity of three different commercial herbal (Aloe vera L. and Fragaria vesca L. extracts) toothpastes [LR Aloe vera (HTP1), ESI Aloe fresh (HTP2) and ROCS Teens (HTP3)] against two microorganisms that cause tooth infections. Materials and Methods: An agar disk diffusion method was used to test the antimicrobial activity of three herbal gel toothpastes in the amount of 100 µL against Streptococcus mutans and Staphylococcus aureus. In the second part of the work, the volatile organic compounds of three different commercial herbal toothpastes (HTP1-3) were determined by solid-phase microextraction/gas chromatography-mass spectrometry-flame ionization detection (SPME/GC-MS-FID). Results: The sensitivity of the tested herbal toothpastes toward each microorganism was expressed as the mean of the clear zone within the range of 6-16 mm diameters. HTP1 and HTP2 were found to be more effective against both bacteria compared with HTP3. Oxygenated monoterpenes (99.34%, 91.44%, and 83.48%) were the most abundant groups in the SPME of HTP1-3, respectively. Menthol (25.41%, 35.82%, and 31.15%) and anethole (52.01%, 23.62%, and 38.79%) were the major compounds identified in the SPME analysis of HTP1-3, respectively. Carvone was found only in HTP3 (0.49%) in a small quantity. Conclusion: The commercial herbal toothpastes could have advantages in decreasing bacterial accumulation on teeth with protection of the oral cavity.


Assuntos
Aloe , Fragaria , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Cremes Dentais/farmacologia , Anisóis/análise , Monoterpenos Cicloexânicos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Mentol/análise , Monoterpenos/análise , Extratos Vegetais/análise , Cremes Dentais/química , Compostos Orgânicos Voláteis/análise
17.
Exp Appl Acarol ; 77(4): 585-599, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31089978

RESUMO

Essential oils extracted from the leaves of Libyan Rosemary (Rosmarinus officinalis L.), and Miswak (Salvadora persica L.) were evaluated for their acaricidal and repellent effects on Ixodes ricinus L. nymphs (Acari: Ixodidae) using a bioassay based on an 'open filter paper method'. Rosmarinus officinalis leaf essential oil diluted to 0.5 and 1 µl/cm2 in acetone exhibited, respectively, 20 and 100% tick mortality after about 5 h of exposure. A total of 50 and 95% of I. ricinus nymphs were killed by direct contact with the oil when exposed to lethal concentrations (LC) of 0.7 µl/cm2 (LC50) and 0.95 µl/cm2 (LC95), respectively. The LC50 (0.5 µl/cm2) was reached before the end of the first 24 h of exposure time (ET), as tick mortality at 24 h was 60%. Salvadora persica leaf essential oil at 1 µl/cm2 showed a significant repellency effect against I. ricinus nymphs at 1.5 h ET. A 95% repellency was observed at a repellent concentration (RC95) of 1 µl/cm2 of S. persica, but no significant mortality was recorded at this dose of S. persica oil. Gas chromatography-mass spectrometry analyses showed that the main monoterpenes in both oils were 1,8-cineol, α-pinene, and ß-pinene, although in markedly different proportions. These results suggest that essential oils have substantial potential as alternative approaches for I. ricinus tick control.


Assuntos
Acaricidas , Ixodes , Óleos Voláteis , Rosmarinus/química , Salvadoraceae/química , Animais , Monoterpenos Bicíclicos , Compostos Bicíclicos com Pontes/análise , Eucaliptol/análise , Líbia , Monoterpenos/análise , Ninfa/crescimento & desenvolvimento , Óleos Voláteis/análise
18.
J Agric Food Chem ; 67(24): 6902-6910, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31132263

RESUMO

The autoxidation kinetics of stripped sunflower oil (SSO), squalene (SQ), and p-cymene ( p-C) initiated by 2,2'-azobis(isobutyronitrile) at 303 K were investigated under controlled conditions by differential oximetry in order to build reference model systems that are representative of the natural variability of oxidizable materials, for quantitative antioxidant testing. Rate constants for oxidative chain propagation ( kp) and chain termination (2 kt) and the oxidizability ( kp/√2 kt) were measured using 2,6-di- tert-butyl-4-methoxyphenol, 2,2,5,7,8-pentamethyl-6-chromanol, BHT, and 4-methoxyphenol as reference antioxidants. Measured values of kp (M-1 s-1)/2 kt (M-1 s-1)/oxidizability (M-1/2 s-1/2) at 303 K in chlorobenzene were 66.9/3.45 × 106/3.6 × 10-2, 68.0/7.40 × 106/2.5 × 10-2, and 0.83/2.87 × 106/4.9 × 10-4, respectively, for SSO, SQ, and p-C. Quercetin, magnolol, caffeic acid phenethyl ester, and 2,4,6-trimethylphenol were investigated to validate calibrations. The distinctive usefulness of the three substrates in testing antioxidants is discussed.


Assuntos
Antioxidantes/análise , Espectroscopia de Ressonância Magnética/normas , Monoterpenos/análise , Espectrofotometria Infravermelho/normas , Esqualeno/análise , Óleo de Girassol/química , Calibragem , Cimenos , Oxirredução
19.
J Environ Sci (China) ; 81: 102-118, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30975314

RESUMO

Biological volatile organic compounds (BVOCs) have a large influence on atmospheric environmental quality, climate change and the carbon cycle. This study assesses the composition and diurnal variation in emission rates of BVOCs from Pinus tabuliformis, using an enclosure technique. Environmental parameters (temperature and light intensity) and physiological parameters (net photosynthetic rate, Pn; stomatal conductance, gs; intercellular CO2 concentration, Ci; and transpiration rate, Tr) that may affect emission behavior were continuously monitored. The 10 most abundant compound groups emitted by P. tabuliformis were classified by gas chromatography-mass spectrometry. The dominant monoterpenoid compounds emitted were α-pinene, ß-myrcene, α-farnesene and limonene. The diurnal emission rate of BVOCs changed with temperature and light intensity, with dynamic analysis of BVOCs emissions revealing that their emission rates were more affected by temperature than light. The variation in monoterpene emission rates was consistent with estimates of Pn, gs and Tr. Basal emission rates (at 30 °C,) of the main BVOCs ranged from 0.006 to 0.273 µg  -1/(hr g), while the basal ER standardization coefficients ranged from 0.049 to 0.144 °C-1. Overall, these results provide a detailed reference for the effective selection and configuration of tree species to effectively prevent and control atmospheric pollution.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Pinus/fisiologia , Compostos Orgânicos Voláteis/análise , Monoterpenos Acíclicos , Monoterpenos Bicíclicos , Monoterpenos/análise , Pinus/química , Sesquiterpenos/análise
20.
Food Chem ; 289: 645-656, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955659

RESUMO

We investigated the dynamic changes in norisoprenoids and phenylalanine derivatives in off-vine Vidal blanc. Glycosidically bound as well as free-form volatile compounds were identified by GC-MS in two vintages. Thus, off-vine grape exhibited the development of four higher alcohols (viz. linalool oxide, 2-octanol, 1-pentanol, and 1-heptanol), C13-norisoprenoids (α-ionone), phenylalanine-derivates (2-phenylethanol), whereas ß-ionone and geranial showed high correlation in on-vine grape. Freeze-thaw cycles and desiccation, two exterior stress affect volatile compound development, resulted in content fluctuations during late harvest. Interestingly, the total content of higher alcohols was higher in on-vine grapes than off-vine grapes in two vintages respectively. Interestingly, the content of higher alcohols was higher in off-vine samples in the 2016 and 2017 vintages. In terms of physicochemical parameters, off-vine Vidal showed results similar to those of on-vine sample. Nevertheless, sensorial impression of the grape juice was influenced by interaction of vintages and vine treatments.


Assuntos
Norisoprenoides/análise , Fenilalanina/análise , Vitis/química , Compostos Orgânicos Voláteis/análise , Monoterpenos Acíclicos , Álcoois/análise , Carotenoides/análise , Análise por Conglomerados , Cicloexanóis/análise , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Heptanol/análise , Humanos , Masculino , Monoterpenos/análise , Octanóis/análise , Pentanóis/análise , Paladar , Compostos de Tritil/análise , Vinho/análise
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