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1.
J Chromatogr A ; 1719: 464774, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38422707

RESUMO

Ginseng is beneficial in the prevention of many diseases and provides benefits for proper growth and development owing to the presence of various useful bioactive substances of diverse chemical heterogeneity (e.g., triterpenoid saponins, polysaccharides, volatile oils, and amino acids). As a result, understanding the therapeutic advantages of ginseng requires an in-depth compositional evaluation employing a simple and rapid analytical technique. In this work, three types of surface-activated carbon fibers (ACFs) were prepared by gas-phase oxidation, strong acid treatment, and Plasma treatment to obtain CO2-ACFs, acidified-ACFs, and plasma-ACFs, respectively. Three prepared ACFs were compared in terms of their physicochemical characterization (i.e., surface roughness and functional groups). A separation system was built using a column with modified ACFs, followed by mass spectrometry detection to investigate and determine substances of different polarities. Among the three columns, CO2-ACFs showed the optimum separation effect. 13 strong polar compounds (12 amino acids and1 oligosaccharide) and 15 lesser polar compounds (ginsenosides) were separated and identified successfully within 4 min in the ginseng sample. The data obtained by CO2-ACFs-TOF-MS/MS and UHPLC-TOF-MS/MS were compared. Our approach was found to be faster (4 min vs. 36 min) and greener, requiring much less solvent (1 mL vs. 10.8 mL), and power (0.06 vs. 0.6 kWh). The developed methodology can provide a faster, eco-friendly, and more reliable tool for the high-throughput screening of complex natural matrices and the simultaneous evaluation of several compounds in diverse samples.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/análise , Espectrometria de Massas em Tandem/métodos , Carvão Vegetal , Fibra de Carbono , Dióxido de Carbono/análise , Extratos Vegetais/química , Aminoácidos , Panax/química , Cromatografia Líquida de Alta Pressão/métodos
2.
Mar Pollut Bull ; 160: 111667, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181942

RESUMO

Phthalate esters (PAEs) are a class of the emerging pollutants that pose a potential environmental threat to marine ecosystems. In this study, a simple analytical method using ultrasound-assisted extraction combined with gas purges microsyringe extraction (GP-MSE) coupled with GC-MS was utilized for the reliable and rapid determination of PAEs in different types of marine sediment. The analytical results showed that the method exhibited excellent reproducibility, linear responses, and detection limits, which verified the suitability of the method for the determination of PAEs in marine sediment. This approach requires minimal reagents, solvents, and sample pretreatment procedures as well as a short analysis time; thus, procedural blanks can be kept to a minimum. This method was demonstrated to be a highly efficient and sensitive quantitative analytical method for the simple detection of PAEs in marine sediment.


Assuntos
Ésteres , Ácidos Ftálicos , Ecossistema , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos , Ácidos Ftálicos/análise , Reprodutibilidade dos Testes
3.
Sci Total Environ ; 703: 134763, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31757545

RESUMO

A total of 29 sediment samples were collected from the East China Sea (ECS), with the Yangtze River estuary and the Zhejiang costal area. These sediment samples were analyzed for 6 phthalate esters (PAEs) and 16 polycyclic aromatic hydrocarbons (PAHs): the ΣPAEs and ΣPAHs concentrations ranged between 1649.5 and 8451.5 ng g-1 (mean = 3446.3 ng g-1) and 57.5-364.5 ng g-1 (mean = 166.2 ng g-1), respectively. Overall, the PAEs and PAHs concentrations gradually decreasing in the offshore and southward directions: their compositions and distributions suggest they could have mainly derived from the Yangtze River. In particular, their distribution was influenced by the sources' proximity, hydrodynamics, and sediment geochemistry (i.e., TOC content and grain size). A classical two-end member model was utilized to estimate the fraction of terrestrial organic carbon in the sediments of the ECS. When the sediment was dominated by terrestrial-derived organic matter (OM), the concentrations of PAEs and PAHs were significantly correlated to the TOC content and gran size of the sediments. In contrast, the poor correlation of TOC content and grain size with PAEs in those sediments dominated by marine-derived OM, implied that the distribution of PAEs in the ECS was mainly related to land-based inputs, (especially to that of the Yangtze River). Regardless of the origin of most of the OM contained in the sediments, we observed positive correlations between the TOC content, and grain size of those containing PAHs. These results suggest that the distribution of PAHs in the ECS was not only related to the Yangtze River input, but also to the geochemical characteristics of the sediments.

4.
Anal Chim Acta ; 879: 63-8, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26002478

RESUMO

Phthalate esters (PAEs) are commonly used as nonreactive plasticisers in vinyl plastics to increase the flexibility of plastic polymers. Numerous studies have indicated that the PAEs as a class of endocrine-disrupting chemicals. In addition, the studies have also shown that a major source of human exposure to phthalates is the diet. To date, the largest problem in PAEs analysis is the high blank value because PAEs are widely used in various applications and products. To overcome this shortcoming, gas purge microsyringe extraction (GP-MSE) was applied, which established a new and low-blank-value analytical method for PAE analysis to analyse PAEs in foodstuffs. In this study, GP-MSE was used as a clean-up method, and the overall recoveries ranged from 85.7 to 102.6%, and the RSD was less than 10%. More importantly, this method can overcome the problem of the high blank value in PAE analysis. This method was applied for measuring PAEs in 78 foodstuffs. The results showed that a wide variety of PAE concentrations were found in the different groups, and the content of PAEs (varies from 658 to 1610 ng g(-1) fresh weight) is greatest in seafood. The concentrations were in the following order: DEHP>DBP>DEP≈DMP>BBP≈DNOP. Finally, the daily intake of PAEs was estimated for adults based on the levels of PAEs in foodstuffs. The total EDIdiet values of 3.2 and 12.9 µg kg(-1) bw d(-1) were calculated for DEHP based on the mean and highest concentrations in foodstuffs, respectively.


Assuntos
Disruptores Endócrinos/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Ftálicos/análise , Animais , Bebidas/análise , China , Análise de Alimentos/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Humanos , Extração Líquido-Líquido/instrumentação , Extração Líquido-Líquido/métodos , Carne/análise , Alimentos Marinhos/análise
5.
Chemosphere ; 119: 289-294, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25036943

RESUMO

The Changbai (also known as "Baekdu") Mountain, on the border between China and North Korea, is the highest mountain (2750 m) in northeastern China. Recently, this mountain region has experienced a dramatic increase in air pollution, not only because of increasing volumes of tourism-derived traffic but also because of the long-range transport of polluted westerly winds passing through major industrial and urban cities in the eastern region of China. To assess the relative importance of the two sources of pollution, 16 polycyclic aromatic hydrocarbons (PAHs) as model substances were determined in the mountain soil. A total of 32 soil samples were collected from different sides of the mountain at different latitudes between July and August of 2009. The ∑PAH concentrations were within the range 38.5-190.1 ng g(-1) on the northern side, 117.7-443.6 ng g(-1) on the southern side, and 75.3-437.3 ng g(-1) on the western side. A progressive increase in the level of ∑PAHs with latitude was observed on the southern and western sides that face the westerly wind with abundant precipitation. However, a similar concentration gradient was not observed on the northern side that receives less rain and is on the leeward direction of the wind. The high-molecular-weight PAH compounds were predominant in the soils on the southern and western sides, while low-molecular-weight PAHs dominated the northern side soils. These findings show that the distribution of PAHs in the mountain soil is strongly influenced by the atmospheric long-range transport and cold trapping.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , China , Monitoramento Ambiental , Vento
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