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1.
J Ethnopharmacol ; 322: 117640, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38135235

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Solanum lycocarpum A. St. Hil. (Solanaceae) is a species from the Brazilian Cerrado, exhibiting several medicinal properties, being used by the population in the treatment of ulcers, bronchitis, asthma and hepatitis, which involve inflammatory processes. AIM OF THIS STUDY: This study aimed to chemically characterize the dichloromethane fraction (DCM), as well as verify its antinociceptive, anti-inflammatory and antioxidant potential. MATERIALS AND METHODS: The DCM fraction was obtained by partitioning the ethanol extract. The chemical constituents of the DCM fraction were characterized by LC-DAD-MS. The DPPH and FRAP assays were used to evaluate the antioxidant potential. The carrageenan-induced paw edema model was used to assess the anti-inflammatory effects, and the inflammatory infiltrate was evaluated by qualitative and quantitative histological analyses. The antinociceptive action of the DCM fraction was evaluated by acetic acid-induced abdominal writhing test, formalin-induced nociception and hot-plate test. RESULTS: Steroidal alkaloids solasonine, solasodine and solamargine, as well as the alkaloid peiminine/imperialine and caffeoylquinic acids, were annotated in DCM fraction by LC-DAD-MS. The DCM fraction showed antioxidative action in the in vitro DPPH and FRAP tests, as well as an anti-inflammatory effect for the three evaluated doses of 30, 100 and 300 mg/kg in the fourth and sixth hours after the administration of carrageenan. The histological analyses evidenced considerably reduction in leukocyte migration and the number of polymorphonuclear leukocytes. The study also demonstrated antinociceptive activity for the DCM fraction, which reduced abdominal writhing at three concentrations evaluated, as well as a decrease in paw licking in the formalin-induced nociception test both in the neurogenic phase and the inflammatory phase, with greater effectiveness compared to the anti-inflammatory indomethacin. The DCM fraction also increased the latency time of the animals in the hot plate test 60 min after treatment, although it did not seem to involve the opioidergic system. CONCLUSION: This work evidenced that the dichloromethane fraction of S. lycocarpum fruit possesses antinociceptive and anti-inflammatory potential, which supports its use in folk medicine for management inflammatory conditions.


Assuntos
Alcaloides , Solanum , Animais , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos/química , Carragenina , Cloreto de Metileno/efeitos adversos , Cloreto de Metileno/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Solanum/química , Frutas/química , Antioxidantes/análise , Dor/induzido quimicamente , Dor/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/química , Alcaloides/uso terapêutico , Edema/induzido quimicamente , Edema/tratamento farmacológico
2.
Chem Biodivers ; 21(2): e202301528, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38116850

RESUMO

Immortelle, a revered Mediterranean medicinal plant, is celebrated for its potent essential oil renowned in the cosmetic industry for its skin-enhancing properties. Yet, immortelle hydrosol, an often-overlooked byproduct, holds promise in cosmetics due to its compatibility with polar active ingredients. This study investigates the chemical composition of immortelle hydrosol by employing liquid-liquid extraction (LLE) to transfer volatile organic components into nonpolar solvents. Four solvents - chloroform, dichloromethane, hexane, and benzene - were assessed through ten consecutive extractions from industrially produced immortelle hydrosol. Quantification was achieved using GC analysis with tetradecane as an internal standard. Chloroform emerged as the most efficient solvent, yielding 2447.0 mg/L of volatile compounds, surpassing dichloromethane, hexane, and benzene. Key compounds in immortelle hydrosol included 3-pentanone, 2-methyl-1-butanol, and γ-terpineol. Importantly, the study revealed that a portion of essential oil compounds persists in the hydrosol even after ten LLE cycles, with optimal results achievable in five extractions (~92 % in most cases).


Assuntos
Hexanos , Óleos Voláteis , Solventes , Benzeno/análise , Clorofórmio/análise , Cloreto de Metileno/análise , Extração Líquido-Líquido , Óleos Voláteis/química
3.
Artigo em Inglês | MEDLINE | ID: mdl-38035540

RESUMO

Carotenoids, such as lycopene and ß-carotene, have been widely recognized for their antioxidant properties and potential health benefits. Accurate quantification of carotenoids in plant extracts is essential for nutritional assessment, quality control, and research investigations. This study introduces an innovative method for quantifying lycopene and ß-carotene, in plant extracts and aims to bridge the gap between complex and expensive carotenoid quantification techniques and the need for accessible methods that can be widely adopted. The primary difference between HPLC and HPTLC lies in the medium used for separation. HPLC employs a liquid phase within columns, while HPTLC utilizes a thin layer of adsorbent on a plate. This distinction impacts factors like equipment, cost, and analysis time. The VisionCats software, combined with the CAMAG Visualizer-2, allows the semi-quantification of metabolites using an image-based evaluation method enabling the simultaneous assessment of qualitative and semi-quantitative information from the HPTLC images. Sample preparation involves washing and drying the vegetal material, followed by dichloromethane extraction. HPTLC analysis is performed using the CAMAG Advanced Herbal System, and the validation studies include establishing calibration curves and determining the detection threshold and minimum quantification threshold for lycopene and ß-carotene. Specificity and precision were evaluated to ensure accurate identification and repeatability of the method. Data analysis involves selecting the regression method based on the nature of the data and assessing the goodness of fit using the R2 value. The results showed distinct peaks corresponding to lycopene and ß-carotene in the chromatograms of the plant extract samples. The visualizer-based method demonstrates good specificity and precision, with no interfering peaks observed and low relative standard deviation. The method shows promising results regarding specificity, precision, and reliability. It has the potential for broader implementation in carotenoid research and rapid monitoring of carotenoid content in various agricultural and food products, particularly in resource-limited settings. Further optimization and validation on a wider range of samples would enhance the applicability of this method in carotenoid research. Sample preparation involves washing and drying the vegetal material, followed by dichloromethane extraction. HPTLC analysis is performed using the CAMAG Advanced Herbal System, and the validation studies include establishing calibration curves and determining the detection threshold and minimum quantification threshold for lycopene and ß-carotene. Specificity and precision were evaluated to ensure accurate identification and repeatability of the method. Data analysis involves selecting the regression method based on the nature of the data and assessing the goodness of fit using the R2 value. The results showed distinct peaks corresponding to lycopene and ß-carotene in the chromatograms of the plant extract samples. The visualizer-based method demonstrates good specificity and precision, with no interfering peaks observed and low relative standard deviation. The method shows promising results regarding specificity, precision, and reliability. It has the potential for broader implementation in carotenoid research and for rapid screening and monitoring of carotenoid content in various agricultural and food products, particularly in resource-limited settings. Further optimization and validation on a wider range of samples would enhance the applicability of this method in carotenoid research.


Assuntos
Solanum lycopersicum , beta Caroteno , Licopeno , beta Caroteno/análise , Reprodutibilidade dos Testes , Cloreto de Metileno/análise , Carotenoides , Extratos Vegetais
4.
Se Pu ; 41(8): 698-706, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-37534557

RESUMO

Short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) have attracted significant attention because of their persistence, biotoxicity, bioaccumulation, and long-range migration. Given their worldwide detection in a variety of environmental matrices, concerns related to the high exposure risks of SCCPs and MCCPs to humans have grown. Thus, knowledge of the contamination patterns of SCCPs and MCCPs and their distribution characteristics in the vivo exposure of humans is of great importance. However, little information is available on the contamination of SCCPs and MCCPs in human blood/plasma/serum, mainly because of the difficulty of sample preparation and quantitative analysis. In this study, a new blood sample pretreatment method based on Percoll discontinuous density gradient centrifugation was developed to separate plasma, red blood cells, white blood cells, and platelets from human whole blood. A series of Percoll sodium chloride buffer solutions with mass concentrations of 1.095, 1.077, and 1.060 g/mL were placed in a centrifuge tube from top to bottom to establish discontinuous density gradients. The dosage for each density gradient was 1.5 mL. Human whole blood samples mixed with 0.85% sodium chloride aqueous solution were then added to the top layer of the Percoll sodium chloride solution. After centrifugation, the whole blood was separated into four components. The plasma was located at the top layer of the centrifuge tube, whereas the platelets, white blood cells, and red blood cells were retained at the junction of the various Percoll sodium chloride solutions. The sampling volume of human whole blood and incubation time were optimized, and results indicated that an excessively long incubation time could lead to hemolysis, resulting in a decrease in the recoveries of SCCPs and MCCPs. Therefore, a sampling volume of 1.5 mL and incubation time of 10 min at 4 ℃ were adopted. The cells of the blood components were further broken and extracted by ultrasonic pretreatment, followed by multilayer silica gel column chromatography for lipid removal. The use of 80 mL of n-hexane-dichloromethane (1∶1, v/v) and 50 mL of dichloromethane as the elution solvents (collected together) for the gel column separated the SCCPs and MCCPs from the lipid molecules in the blood samples. Gas chromatography-electron capture negative ion-low resolution mass spectrometry (GC-ECNI-LRMS) was used to determine the SCCPs and MCCPs. Quantification using the corrected total response factor with degrees of chlorination was achieved with linear corrections (R2=0.912 and 0.929 for the SCCPs and MCCPs, respectively). The method detection limits (MDLs) for the SCCPs and MCCPs were 1.57 and 8.29 ng/g wet weight (ww, n=7), respectively. The extraction internal standard recoveries were 67.0%-126.6% for the SCCPs and 69.5%-120.5% for the MCCPs. The developed method was applied to determine SCCPs and MCCPs in actual human whole blood samples. The contents of SCCPs and MCCPs were 10.81-65.23 and 31.82-105.65 ng/g (ww), respectively. Red blood cells exhibited the highest contents of CPs, followed by plasma, white blood cells, and platelets. The proportions of SCCPs and MCCPs in red blood cells and plasma were 70% and 66%, respectively. In all four components, the MCCP contents were higher than the SCCP contents, and the ratios of MCCPs to SCCPs ranged from 1.04 to 3.78. Similar congener patterns of SCCPs and MCCPs were found in the four components of human whole blood. C10-CPs and C14-CPs were predominantly observed in the SCCPs and MCCPs, respectively. In summary, a simple and efficient method was proposed to determine low concentrations of SCCPs and MCCPs in human blood with high sensitivity and selectivity. This method can meet requirements for the quantitative analysis of SCCPs and MCCPs in human blood components, thereby providing technical support for human health risk assessment.


Assuntos
Hidrocarbonetos Clorados , Parafina , Humanos , Parafina/análise , Cloreto de Metileno/análise , Hidrocarbonetos Clorados/análise , Elétrons , Cloreto de Sódio/análise , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lipídeos , China
5.
Mar Environ Res ; 190: 106087, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37473598

RESUMO

Fatty acids (FAs) are used, often in combination with stable isotopes (SIs), as chemical biomarkers to assess the contribution of different prey to the diet of consumers and define food web structure and dynamics. Extraction of lipids is traditionally carried out using methanol (MeOH) combined with chloroform or dichloromethane, these latter being well-known environmental pollutant and potential carcinogenic agents. Recently, extraction protocols based on methyl tert-butyl ether (MTBE) and MeOH have been proposed as an alternative to halogenated solvents in lipidomic studies. However, no specific investigation has been performed to assess MTBE suitability in marine ecological studies including FA analysis together with SI measurements. We used an analytical workflow for qualitative and quantitative analysis of FAs and SIs in field samples of phytoplankton, zooplankton and the scyphomedusa Pelagia noctiluca, applying MTBE in comparison with chloroform- and dichloromethane-based protocols for total lipid extraction. Our analysis suggested that MTBE is a reliable substitute for lipid extraction in trophic ecology studies in marine planktonic organisms.


Assuntos
Ácidos Graxos , Cadeia Alimentar , Ácidos Graxos/análise , Plâncton , Clorofórmio/análise , Cloreto de Metileno/análise , Fluxo de Trabalho , Metanol , Isótopos de Carbono/análise
6.
Environ Sci Technol ; 57(32): 12010-12018, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37506359

RESUMO

Determination of microplastics and nanoplastics (MNPs), especially small MPs and NPs (<150 µm), in solid environmental matrices is a challenging task due to the formation of stable aggregates between MNPs and natural colloids. Herein, a novel method for extracting small MPs and NPs embedded in soils/sediments/sludges has been developed by combining tetramethylammonium hydroxide (TMAH) digestion with dichloromethane (DCM) dissolution. The solid samples were digested with TMAH, and the collected precipitate was washed with anhydrous ethanol to eliminate the natural organic matter. Then, the MNPs in precipitate were extracted by dissolving in DCM under ultrasonic conditions. Under the optimized digestion and extraction conditions, the factors including sizes and concentrations of MNPs showed insignificant effects on the extraction process. The feasibility of this sample preparation method was verified by the satisfactory spiked recoveries (79.6-91.4%) of polystyrene, polyethylene, polypropylene, poly(methyl methacrylate), polyvinyl chloride, and polyethylene terephthalate MNPs in soil/sediment/sludge samples. The proposed sample preparation method was coupled with pyrolysis gas chromatography-mass spectrometry to determine trace small MPs and NPs with a relatively low detection limit of 2.3-29.2 µg/g. Notably, commonly used MNPs were successfully detected at levels of 4.6-51.4 µg/g in 6 soil/sediment/sludge samples. This proposed method is promising for evaluating small solid-embedded MNP pollution.


Assuntos
Microplásticos , Plásticos , Plásticos/análise , Cromatografia Gasosa-Espectrometria de Massas , Esgotos/química , Cloreto de Metileno/análise , Solubilidade , Solo/química , Digestão
7.
Se Pu ; 41(6): 535-542, 2023 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-37259879

RESUMO

Polybrominated diphenyl ethers (PBDEs) are used as additive flame retardants. Because they lack the ability to form chemical bonds, PBDEs can easily enter the sediment environment. The accurate qualitative and quantitative analysis of PBDEs in sediments is of great importance for the accurate assessment of PBDE pollution in this environment. Sediments contain many impurities. Therefore, PBDEs in sediment should be purified before analysis to reduce the matrix effect. A method based on gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI/MS) was developed to determine 13 PBDEs in marine sediment samples using a column packed with deactivated silica gel, acidified silica gel, Florisil, and anhydrous sodium sulfate. Sediment samples were extracted by ultrasonication with a mixed solvent of n-hexane-dichloromethane (3∶1, v/v). After two cycles of ultrasonic extraction, the extract was purified by a composite chromatographic column and eluted with n-hexane-dichloromethane (3∶1, v/v). Thirteen PBDEs were determined by GC-NCI/MS in selected-ion monitoring (SIM) mode. The effects of different fillers, eluents, and elution volumes on the purification of PBDEs in the composite column were compared and analyzed, and the GC-NCI/MS analysis conditions were optimized. Three different packing columns were used to purify the sample extract. The first column was packed with 3 g of deactivated silica, 6 g of acidic silica, 3 g of deactivated silica, 3 g of Florisil, and 6 g of anhydrous sodium sulfate; the second column was packed with 3 g of Florisil, 3 g of deactivated silica, 6 g of acidic silica, 3 g of deactivated silica, and 6 g of anhydrous sodium sulfate; and the third column was packed with 3 g of deactivated silica, 6 g of acidified silica, 3 g of deactivated silica, and 6 g of anhydrous sodium sulfate. Among these columns, that packed with 3 g of deactivated silica, 6 g of acidic silica, 3 g of deactivated silica, 3 g of Florisil, and 6 g of anhydrous sodium sulfate showed the best purification effect. The 13 PBDEs showed good linearity in the mass concentration range of 0.1-20 µg/L with correlation coefficients (r2) greater than 0.995 (decabromodiphenyl oxide (BDE-209), r2>0.99). The limits of quantification (S/N=10) was 0.002-0.126 µg/kg. The average recoveries of the 13 PBDEs at three spiked levels of 0.2, 1.0, and 4.0 µg/kg were 85.3%-101.3%, 84.8%-113.6%, and 86.3%-94.7% with relative standard deviations of 4.4%-14.0%, 0.4%-4.9%, and 1.9%-6.6%, respectively. These findings indicate that the method has high sensitivity and accuracy as well as good precision. Finally, the method was applied to the analysis and detection of PBDEs in actual marine sediment samples. The results revealed that the sediment samples contained different contents of the 13 PBDEs, and high detection rates were obtained for lower-brominated PBDE homologs. The detection rate of bis(4-bromophenyl) ether (BDE-15) was 100%, and the detected content of BDE-209 was as high as 60.49 µg/kg. These results demonstrate that the developed method is suitable for the accurate qualitative and quantitative analysis of PBDEs in marine sediment samples.


Assuntos
Éteres Difenil Halogenados , Cloreto de Metileno , Éteres Difenil Halogenados/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cloreto de Metileno/análise , Sílica Gel , Espectrometria de Massas , Dióxido de Silício
8.
Clin Chim Acta ; 546: 117395, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37211176

RESUMO

Roxadustat is an oral inhibitor of hypoxia-inducible factor prolyl hydroxylase which increases erythropoiesis. It can therefore be used as a doping agent. No data are available on how to measure roxadustat in hair and on the concentration found in treated patients. The aim of this study was to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of roxadustat in hair and to apply it to a chronically treated patient. After decontamination with dichloromethane, testosterone-D3 used as an internal standard and phosphate buffer pH 5.0 were added to 20 mg of hair and incubated for 10 min at 95 °C. Four ml of dichloromethane were used for extraction and reconstituted into the mobile phase, 10 µL were injected into the chromatographic system. The method was linear in the range 0.5-200 pg/mg, accurate and precise (evaluated at 3 levels) and was successfully applied to measure roxadustat in a brown-haired patient treated pharmacologically with 100-120 mg 3 days a week. Results were stable between 41 and 57 pg/mg in the 6 proximal 1 cm segments. This first method describing the measurement of roxadustat in hair appears to be suitable for the quantification of this compound in clinical or doping control cases.


Assuntos
Cloreto de Metileno , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Cloreto de Metileno/análise , Cabelo/química
9.
J Chromatogr A ; 1684: 463537, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36240707

RESUMO

Tobacco alkaloids are important precursors of carcinogenic tobacco-specific nitrosamines. Therefore, accurate quantification of tobacco alkaloids is highly important. This study investigates the compensation effects of novel analyte protectants (APs) for matrix effects (MEs) to determine seven minor tobacco alkaloids (nornicotine, myosmine, anabasine, anatabine, nicotyrine, 2,3'-bipyridine, and cotinine) in mainstream cigarette smoke with high accuracy and robustness. By comparing the heights and shapes of the chromatographic peaks before and after the addition of APs to standard solutions prepared in dichloromethane and cigarette smoke solutions, the compensation effects of 12 APs and their combinations on the MEs of seven minor tobacco alkaloids were evaluated, and the best combination of 2-pyridylethylamine (2 mg/mL)+1,2-decanediol (1 mg/mL) was identified. This AP combination could effectively improve the shapes and increase the heights (by 7-371%) of chromatographic peaks for standard solutions prepared in dichloromethane and cigarette smoke solutions. Before the addition of this AP combination, the slope ratios of the calibration curves for two types of standard solutions of the seven target chemicals were 71.4-159.8%, while they were 87.4-105.6% after the addition, indicating that this AP combination reduced the matrix difference between pure solvent and cigarette smoke solution. After adding the AP combination, the standard curves of solutions prepared in dichloromethane showed good linearity (r2 ≥ 0.999), the spiked recoveries were between 80.9% and 119.6%, and the inter- and intraday precisions were between 1.5-9.5% and 3.1-8.5%, respectively. Three commercial cigarette samples and one mixed standard solution were also tested under four different instrument working conditions to verify the long-term accuracy and ruggedness of the approach in routine real-world analysis of the method. The results showed that the RSD values were higher (3.5-25.4%) without the AP combination than that (<6.7%) with the AP combination. Because of its high accuracy, precision, and robustness, this method has good practical prospects.


Assuntos
Alcaloides , Fumar Cigarros , Produtos do Tabaco , Nicotiana/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cloreto de Metileno/análise , Produtos do Tabaco/análise , Alcaloides/análise
10.
Pak J Pharm Sci ; 35(4(Special)): 1261-1267, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36218105

RESUMO

The purpose of this study was to purify the phytoconstituents and to explore the antibacterial, antifungal, phytotoxic and cytotoxic potential of dichloromethane and methanol extracts of aerial and root parts of Trigonella polycerata. The phytochemical study on methanol extract of aerial parts of the plant led to the isolation and purification of seven compounds that were identified as 3,4-dimethoxycinnamaldehyde, Trigocoumarin, 6,7,8-trimethoxycoumarin, Penduletin, 5-hydroxy-3,6,7,4´-tetramethoxyflavone, 3,5,7-trihydroxy-6,4-dimethoxyflavone and 5-hydroxy-4,7-dimethoxyflavone. These structures were elucidated by interpretation of EI-MS and NMR spectral data. The plant aerial parts methanol extract (TPAM) demonstrated higher antibacterial (78.99%), phytotoxic (85% growth regulation at 1000µg/mL) and cytotoxic activities (LD50: 45.643µg/mL). While the methanol root extract (TPRM) was highly active against bacteria's; Salmonella typhi (71.56%), Staphylococcus aureus (70.15%), Escherichia coli (69%), fungi like Candida albicans (70.21%) and moderately active against Brine shrimp larvae (LD50: 125.663µg/mL). The dichloromethane aerial (TPAD) and root (TPRD) extracts exhibited significant antibacterial (78.03% and 50.21% inhibitions respectively) and phytotoxic (55% growth regulation at 1000µg/mL) potential. Only TPAD indicated the best inhibition against fungi; Aspergillus flavus (75.31%) and moderate inhibition against Microsporum canis (42.21%). This phytochemical and biological work is the first time reported in Trigonella polycerata.


Assuntos
Trigonella , Antibacterianos/química , Antibacterianos/toxicidade , Antifúngicos/química , Metanol , Cloreto de Metileno/análise , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química , Extratos Vegetais/toxicidade
11.
Se Pu ; 40(10): 937-943, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36222257

RESUMO

Emerging pollutants (EPs) are chemical substances that are commonly not regulated and can be detected at low or very low concentrations. However, EPs have triggered special concern because their long-term adverse effects on the environment and human health remain unknown. Most EPs show biological toxicity, environmental persistence, and bioaccumulation. Even at low concentrations in the environment, EPs may pose significant environmental and health risks. Therefore, their treatment has been explicitly included in the 14th Five Year Plan for National Economic and Social Development of the People's Republic of China and the Outline of the Long-term Goals for 2035. Soil is a source of pollutants, and its quality is directly related to economic development, ecological security, and people's livelihood. At present, China's soil environmental monitoring system is not perfect, and the ability to monitor these new organic pollutants is lagging. Therefore, to strengthen the supervision of construction and agricultural land soil environments, it is essential to strengthen the soil environment monitoring ability for these EPs and establish a reliable, steady, and economic analysis method, including their separation and analysis methods in soil. Polychlorinated naphthalenes (PCNs) have received considerable attention as emerging halogenated compounds. They were listed in Annexes A and C of the Stockholm Convention on persistent organic pollutants (POPs) in 2015 because of their persistence, multimedia fate, and toxicity. PCNs have now been detected in the surrounding soils. Owing to their trace levels in complex soil, high requirements have been put forward for the pretreatment and instrument analysis of PCNs. This study aims to develop a new method for the selective purification of PCNs in soil, which can not only effectively remove lipids and other interferences in soil but also effectively reduce time, labor, and material costs in the pre-treatment process. Based on the physicochemical properties of the 13X molecular sieve, it was explored to purify soil-extracts as solid-phase extraction (SPE) sorbents. With n-hexane as the loading and rinsing solvent, 10 mL of a dichloromethane/n-hexane mixture (2∶15, v/v) was used to elute the PCNs. Moreover, selective separation of target substances from lipid macromolecules and other interferences could be achieved simultaneously. For the selective separation of PCNs, the average recovery of the internal standard could reach 56.1% to 88.0%. 13X molecular sieves are superior to gel permeation chromatography (GPC) and Florisil SPE, and they exhibit good cleanup efficiency similar to a multilayer silica gel/alumina column (53.0%-117.0%). Although the obtained recoveries are not as high as those obtained with a multilayer silica gel/alumina column, 13X molecular sieves have advantages in terms of simple operation, environmental friendliness, and low cost. Based on these fundamental experiments, accelerated solvent extraction was used to extract targets in soil, molecular sieves were used as SPE sorbents for purification, and GC-MS/MS was employed for PCN analysis. This method was developed as a systematic analytical method for PCNs determination. The method detection limits (MDLs) for PCN homologs were in the range of 0.009-0.6 ng/g. The precision and accuracy of the method were evaluated using spiked matrices. At three spiked levels (4, 10, and 18 ng), the recoveries of PCNs (CN-3, 13, 42, 46, 52, 53, 73, and 75) were 70%-128%, 71%-115%, and 61%-114%, respectively, and the corresponding relative standard derivations were 4.2%-23%, 6.5%-31% and 4.7%-22%. Thus, this method meets the requirements of trace analysis and shows acceptable parallelism, sensitivity, accuracy, and precision, thus being feasible for the analysis of emerging pollutant. The method is expected to play an important role in sample pretreatment in the future, especially for the nationwide investigation of soil pollution.


Assuntos
Poluentes Ambientais , Solo , Humanos , Óxido de Alumínio , Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hexanos , Lipídeos , Cloreto de Metileno/análise , Naftalenos/análise , Poluentes Orgânicos Persistentes , Sílica Gel , Extração em Fase Sólida , Solventes/análise , Espectrometria de Massas em Tandem
12.
BMC Complement Med Ther ; 22(1): 280, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289484

RESUMO

BACKGROUND: Bersama abyssinica is a common herb in Africa, with diverse medical uses in different areas. The plant is well-known in Tanzania for treating respiratory disorders such as TB, tonsillitis, bronchitis, and asthma, and it has lately been utilized to treat COVID-19 symptoms. Water extract of leaf and stem bark has been registered as an herbal medication known as 'Coviba Dawa' in Tanzania for the relief of bacterial respiratory infections. The extracts, however, have not been scientifically tested for their anti-viral activities. The aim of this work was to test for the cytotoxicity and antiviral effects of bioactive ingredients from B. abyssinica extracts against the Delta variant of the SARS-CoV-2 coronavirus. METHODS: B. abyssinica leaves and stem bark were dried under shade in room temperature and then pulverized to obtain small pieces before soaking into different solvents. One hundred grams of each, leaves and stem bark, were extracted in petroleum ether, dichloromethane, ethyl acetate and methanol. Water extract was obtained by decoction of stem bark and leaves into water. Phenols, flavonoids, tannins, and antioxidants were confirmed as components of the extracts. Analysis of polar extracts of bark stem bark and leaves was done. Antiviral screening and cytotoxicity experiments were conducted in a Biosafety Level 3 (BSL-3) Laboratory facility according to International Standard Operating Procedures (SOPs). RESULTS: By the use of LC-MS/MS analysis, this study confirmed the existence of four phenolic compounds in B. abyssinica water extract; 2,4-di-tert-butylphenol, 4-formyl-2-methoxyphenyl propionate, 7,8-Dihydroxy-4-methylcoumarin, and 2,3, 6-trimethoxyflavone with antioxidant activity. This study showed that, while the water extracts of B. abyssinica had significant antiviral activity against SARS Cov2 virus, it showed no cytotoxicity effect on Vero E6 cells. In particular, the water extract (Coviba dawa) showed 75% while ethylacetate fraction of B. abyssinica leaves showed a 50% in vitro viral inhibition, indicating that these substances may be useful for the development of future anti-viral agents. CONCLUSION: We therefore recommend isolation of compounds for further profiling and development with a broader concentration range. We further recommend studies that determine the antiviral activity of extracts of B.abyssinica on other viral pathogens of clinical concern.


Assuntos
Tratamento Farmacológico da COVID-19 , Magnoliopsida , Antioxidantes/análise , Extratos Vegetais/uso terapêutico , Antivirais/farmacologia , Água , SARS-CoV-2 , Cloreto de Metileno/análise , Metanol , Cromatografia Líquida , Propionatos , Espectrometria de Massas em Tandem , Fenóis/farmacologia , Flavonoides/análise , Taninos , Solventes/análise , Tanzânia
13.
Artigo em Inglês | MEDLINE | ID: mdl-36174263

RESUMO

The quantification of tobacco exposure biomarkers is relevant to follow the patients' tobacco use. They allow to discriminate between tobacco users, non-users, passive smokers, and nicotine products users, such as in nicotine replacement therapy. The aim of this study was to develop and validate a quantification method of tobacco biomarkers of choice - nicotine, cotinine, trans-3'-hydroxycotinine, anatabine and anabasine - in urine. The challenge was to develop an easy and rapid liquid chromatography method requiring only one extraction step and allowing simultaneous detections. Some methods are described in the literature but need specific investment in terms of instrumentation and users training. Here, the developed method had to be carried out with instrumentation easily accessible for medical laboratories. The extraction of the analytes was performed by Supported Liquid Extraction (SLE), which consists in liquid-liquid extraction but supported by a sorbent. It allows to insure efficient neutrals extraction with less organic solvent and without any emulsion formation. 200 µl of basified urine - analytes of interest are neutral in this condition - were loaded on Novum SLE 96-Well Plates (Phenomenex) and analytes were eluted with 1 % formic acid in dichloromethane/propan-2-ol (95/5). After solvent evaporation, samples were reconstituted with 100 µl of water for injection. A mass detector (QDa, Waters) was used to detect analytes, this pre-optimised quadrupole mass analyser being less expensive and requiring less adjustments than traditional mass spectrometers while benefiting of the reliability of mass spectral data. This detector was integrated after an Ultra-high performance liquid chromatography (UHPLC) separation on a BEH C18 column (Waters) at a flow rate of 0.5 ml/min. A gradient elution of H2O (pH 10 with NH4OH) and CH3CN was used. Finally, the developed method was validated. This new method is conclusive to assess the patients' tobacco exposure and is easy to implement in medical laboratories.


Assuntos
Abandono do Hábito de Fumar , Humanos , Anabasina/análise , Biomarcadores , Cromatografia Líquida de Alta Pressão , Cotinina , Emulsões , Cloreto de Metileno/análise , Nicotina/análise , Reprodutibilidade dos Testes , Abandono do Hábito de Fumar/métodos , Solventes , Espectrometria de Massas em Tandem/métodos , Uso de Tabaco , Dispositivos para o Abandono do Uso de Tabaco , Água
14.
Chem Biodivers ; 19(10): e202200022, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35997661

RESUMO

This study evaluated the diuretic and antiurolithic effect of methanolic extract (MEGHL), dichloromethane (DCM), and ethyl acetate (EtA) fractions obtained from the leaves of Garcinia humilis, a medicinal plant known as achachairu and native to South American countries such as Bolivia, Peru, and Brazil. For the analysis of diuretic effect, the female rats received the treatment with MEGHL (3, 10, and 30 mg/kg), DCM (1, 3 and 10 mg/kg), EtA (1, 3, and 10 mg/kg), hydrochlorothiazide (HCTZ; 10 mg/kg), or vehicle (VEH) after an overload of saline solution. At the end 8 h of the experiment, the urinary parameters were measured. Additionally, the antiurolithic effect was analyzed, in which sodium oxalate was added in synthetic urine in the presence or absence of MEGHL, DCM, and EtA in different concentrations (0.1, 0.3, and 1 mg/mL). MEGHL, DCM, and EtA were able to promote 8-h diuresis in rats. MEGHL treatment at dose 30 mg/kg was accompanied by increased urinary Na+ , K+ and Cl- excretion. Moreover, the DCM and EtA fractions treatment increased K+ and Cl- excretion in the urine, although it does not cause any change in Na+ elimination. All the preparations were able to exert an antiurolithic effect in vitro, decreasing the number of calcium oxalate crystals of the monohydrate and dihydrate types. Taking together, the results presented herein showed that the preparations of G. humilis leaves are promising strategies to induce diuresis and antiurolithic effects.


Assuntos
Garcinia , Plantas Medicinais , Ratos , Animais , Diuréticos/farmacologia , Diuréticos/análise , Oxalato de Cálcio/análise , Cloreto de Metileno/análise , Solução Salina , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/análise , Ratos Wistar , Folhas de Planta/química , Hidroclorotiazida/análise , Hidroclorotiazida/farmacologia , Brasil
15.
Se Pu ; 40(7): 644-652, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-35791603

RESUMO

Polychlorinated naphthalenes (PCNs) have a structure similar to that of polychlorinated biphenyls (PCBs) and represent a new type of persistent organic pollutants (POPs) that are widely present in the environment and biological communities. PCNs can migrate and transform via different environmental media, which severely affects the health of humans and organisms. Researchers have devoted considerable focus on ambient air pollution. Although the current ambient air quality has not yet limited the concentration of PCNs, the Stockholm Convention has required parties to prohibit and eliminate their production and use. As one of the contracting parties, China is obligated to improve its environmental monitoring. In other words, the development of a method for monitoring PCNs in ambient air is important for understanding ambient air quality and safeguarding human health. PCNs are generally present at trace levels (pg/m3) in ambient air. To achieve accurate quantification of PCNs, high demands are raised on the methods for extraction, purification, and instrumental analysis, which can directly affect the efficiency, accuracy, and sensitivity of a method. Considering the trace-level presence of PCNs in ambient air and the high efficiency and accuracy of the analytical method, accelerated solvent extraction (ASE), combined with column chromatography using a multilayer silica gel column and a neutral alumina column, was established for the extraction and purification of PCNs in ambient air. The important parameters involved in the aforementioned steps, such as the type of extraction and volume of elution solvent, were optimized. The results indicated that dichloromethane-hexane (1∶1, v/v) was the best extraction solvent for the recovery of PCNs. Hexane and dichloromethane-hexane (5∶95, v/v) were used as the elution solvents for the multi-silica gel column and neutral alumina column, respectively. Isotope dilution gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) was used to quantify the target compounds. Gas chromatographic parameters, such as temperature program conditions and inlet temperature, were also optimized. The oven temperature program was as follows: 80 ℃ for 1 min, 80 ℃ to 160 ℃ at 15 ℃/min, 160 ℃ to 265 ℃ at 3 ℃/min, and 265 ℃ to 280 ℃ at 5 ℃/min, followed by holding the temperature at 280 ℃ for 10 min. The inlet temperature was set at 260 ℃. The optimal characteristics of ion pair, collision energy, and ion source temperature were determined by optimizing the key mass spectrometry parameters. The developed instrumental method, combined with suitable sample preparation techniques, was used to determine the concentrations of PCNs in ambient air samples. Quality control (QC) and quality assurance (QA) were performed by adding isotope internal standards before sampling, extraction, and injection analysis to monitor the entire analysis process. The relative standard deviations (RSDs) of the relative response factors (RRFs) for trichloronaphthalene to octachloronaphthalene were less than 16% in the concentration range of 2-100 ng/mL. The method detection limits (MDLs) for PCN homologues were in the range of 1-3 pg/m3(calculated using a sample volume of 288 m3). The precision and accuracy of this method for determining PCNs in ambient air samples were evaluated using a spiked matrix. The average spiked recoveries of trichloronaphthalene to octachloronaphthalene were 89.0%-119.4%, 98.6%-122.5% and 93.7%-124.5% at low, medium, and high spiked concentrations (20, 50, and 90 ng/mL), respectively. The RSDs of the assay results were 1.9%-7.0%, 1.6%-6.6%, and 1.0%-4.8%, respectively. During the entire analysis process, the average recoveries of the sampling and extracted internal standards were 136.2%-146.0% and 42.4%-78.1%, respectively, and the corresponding RSDs were 5.6%-7.5% and 2.7%-17.5%. Thus, this method meets the requirements of trace analysis and exhibits good parallelism, high sensitivity, high accuracy, and good precision, and it is suitable for the accurate quantitative determination of trichloronaphthalene to octachloronaphthalene in ambient air.


Assuntos
Hexanos , Naftalenos , Óxido de Alumínio , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hexanos/análise , Humanos , Isótopos , Cloreto de Metileno/análise , Naftalenos/análise , Sílica Gel , Solventes/análise , Espectrometria de Massas em Tandem/métodos
16.
Environ Res ; 213: 113644, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35697085

RESUMO

Many volatile organic compounds (VOCs) are used for experiments at universities, and most of them contain benzene, toluene, ethylbenzene, xylene, and an extraction solvent of dichloromethane. This study aimed to investigate the indoor concentrations of these five compounds in different locations on campus and to evaluate possible health risks for faculty members and students in a medical university. We selected 10 locations as sampling sites to conduct 4-h monitoring sessions on weekdays each season during 2019-2020. We used a 6-liter canister to collect air samples and analyzed these five VOCs via gas chromatography with a flame ionization detector. Monte Carlo simulation was performed to evaluate the carcinogenic and noncarcinogenic risks of these five VOCs. We found that dichloromethane was the most highly detected compound (median: 621.07 µg/m3; range: 44.01-8523.91 µg/m3), and the Department of Medicine had the highest concentration of the total of these VOCs among all of the locations (median: 5595.29 µg/m3; range: 1565.67-7398.66 µg/m3). The median carcinogenic risks of dichloromethane and benzene were 6.36 × 10-5 (95% confidence interval [CI]: 6.83 × 10-6-7.37 × 10-4) and 5.47 × 10-6 (95% CI: 4.03 × 10-7-2.42 × 10-5), respectively, for faculty members, and the lower risks of 3.14 × 10-5 (95% CI: 3.39 × 10-6-3.64 × 10-4) and 2.69 × 10-6 (95% CI: 1.97 × 10-7-1.19 × 10-5) were estimated for the students. The chronic noncarcinogenic risks of four VOCs were less than one, except for dichloromethane with a median hazard index of 1.92 (95% CI: 2.11 × 10-1-2.22 × 101). This study observed the spatial variation in the concentrations of the total of five VOCs and dichloromethane. The carcinogenic risks were classified as being at the possible level, and the noncarcinogenic risk of dichloromethane was greater than the acceptable level. Increasing local exhaust ventilation during the experiment and reducing the using amount of dichloromethane are recommended actions to reduce VOCs exposures in the medical university.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Benzeno/análise , Benzeno/toxicidade , Monitoramento Ambiental/métodos , Humanos , Cloreto de Metileno/análise , Medição de Risco , Universidades , Compostos Orgânicos Voláteis/análise
17.
Chem Biodivers ; 19(4): e202200068, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35263005

RESUMO

This study focused on the biological evaluation and chemical characterization of Malabaila lasiocarpa Boiss. (M. lasiocarpa) (Family: Apiaceae). The phytochemical profile, antioxidant, enzyme inhibitory of the methanolic, aqueous, dichloromethane, hexane extracts were investigated. Based on UHPLC-HRMS analyses, a total of 101 peaks were annotated or identified for the first time in M. lasiocarpa extracts. They include hydroxybenzoic, hydroxycinnamic, acylquinic acids and their glycosides, C- and O-glycosyl and O-diglycosyl flavonoids. In addition, 10 simple mono- and disubstituted coumarins together with 10 furanocoumarins were tentatively annotated. The methanolic extract possessing the highest phenolic (24.36±0.60 mg gallic acid equivalent/g extract) and flavonoid (69.15±0.37 mg rutin equivalent/g extract) content also exhibited the strongest radical scavenging potential against 2,2-diphenyl-1 picrylhydrazyl (21.73±0.42 mg Trolox equivalent/g extract, respectively), and highest reducing capacity (57.81±0.97 and 28.00±0.40 mg Trolox equivalent/g extract, for cupric reducing antioxidant capacity and ferric reducing antioxidant power, respectively). The dichloromethane extract substantially depressed the tyrosinase (73.92±5.37 mg kojic acid equivalent/g extract), α-amylase (0.63±0.01 mmol acarbose equivalent/g extract) and α-glucosidase (0.69±0.02 mmol acarbose equivalent/g extract) enzymes. This study has produced critical scientific data on M. lasiocarpa which are potential contenders for the development of novel phyto-pharmaceuticals.


Assuntos
Antioxidantes , Apiaceae , Acarbose , Antioxidantes/química , Antioxidantes/farmacologia , Flavonoides/análise , Cloreto de Metileno/análise , Extratos Vegetais/química , Turquia
18.
Environ Geochem Health ; 44(11): 4141-4156, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35022876

RESUMO

Suspended sediments were collected to examine the organic carbon content and n-alkanes in order to assess the impact on water bodies caused by soil and land occupation. For this, samples from distinct areas based on the level of land occupation of the Barigui Watershed and different areas under the influence of human activities were examined. The number of industries increasing along the river was also considered. Twenty-two sediment samples were collected using a time-integrated sediment sampler. Samples were extracted with dichloromethane:methanol (DCM:methanol) (2:1) in an ultrasound bath, treated and injected using gas chromatography coupled with mass spectrometry (GC-MS) for separation and quantification. Twenty-one n-alkanes were identified and were used to track both biogenic and anthropogenic inputs. The concentration of total n-alkanes varied from 38.72 to 222.76 µg g-1, due to the impact of urbanization. Diagnostic indexes indicated high numbers of plants, bacteria and petroleum as n-alkanes sources. The following results were obtained using: carbon preference index (CPI), 1.96-2.22 (rainy season) and 2.12-5.80 (summer season); average chain length (ACL), 30.37-31.17 (rainy season) and 30.05-30.50 (summer season) and terrigenous aquatic ratio (TAR), 0.39-5.47 (rainy season) and 2.98-5.06 (summer season); n-alkanes had two main sources: terrestrial plant and petroleum. It is clear that the source of n-alkanes is different in each season (rainy and dry) demonstrated by n-alkanes occurrence. During the rainy season, there was an increase in organic matter of oil origin which was mainly associated with the increased runoff and rain drainage. Finally, the input of organic matter associated with land occupation and erosion can be distinguished by higher concentration in the most urbanized site (PB).


Assuntos
Petróleo , Poluentes Químicos da Água , Humanos , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Metanol , Cloreto de Metileno/análise , Brasil , Petróleo/análise , Alcanos/análise , Carbono/análise , Solo , Ocupações , Água/análise , Monitoramento Ambiental
19.
J Appl Biomed ; 19(1): 26-39, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34907713

RESUMO

The present study explores pharmacological potential and phytochemicals profiling of Picrorhiza kurroa extracts against mammalian cancer cell lines and pathogenic microbes. Bioactive extracts from roots of Picrorhiza kurroa were recovered in the methanol, 50% aqueous dichloromethane (50 : 50 v/v) and n-hexane. Antimicrobial activity of the bioactive extracts was assessed against selected strains of bacteria and pathogenic fungi. Aqueous dichloromethane extract showed highest zone of growth inhibition (39.06 ± 1.0 mm) towards Staphylococcus aureus bacteria while methanolic extract showed the lowest inhibition (6.3 ± 4.1 mm) to Escherichia coli bacteria. The tested extracts such as methanol and aqueous dichloromethane exhibited higher inhibition antifungal activity against Aspergillus flavus compared to Fusarium oxysporum. As far as cytotoxicity (MTT assay) of the tested extracts is concerned, n-hexane and aqueous dichloromethane extracts were found to be very active against all cancer cell lines (breast cancer MCF7, MDA-MB-231, SKBR3 and ovarian cancer SKOV3). A preliminary phytochemicals profiling was performed in extracts using GC-MS. Several fractions of active extract were separated with HPLC and analyzed using High Resolution Atmospheric Pressure Chemical Ionization Mass Spectrometry (HR-APCI-MS). Two purified compounds (Dihydromikanolide and 1,3-Dicyclohexyl-4-(cyclohexylimino)-2-(cyclohexylethylamino)-3,4-dihydro-1,3-diazetium) were further evaluated for their anticancer activity against ovarian cancer cell line. Our findings depict that all the tested extracts showed considerable anticancer potential through cell viability assays. The purified compound 1 - Dihydromikanolide from methanolic extract was found to be active against ovarian cancer cells and can be explored as a promising nutra-pharmaceutical candidate against ovarian cancer. However, further studies exploring the molecular pathways and in vivo testing are required.


Assuntos
Anti-Infecciosos , Neoplasias Ovarianas , Picrorhiza , Animais , Anti-Infecciosos/farmacologia , Pressão Atmosférica , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Mamíferos , Metabolômica , Metanol/análise , Cloreto de Metileno/análise , Compostos Fitoquímicos/análise , Extratos Vegetais/farmacologia
20.
Ind Health ; 58(1): 22-25, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30996213

RESUMO

The objective of the study is to establish exposure-excretion relationship between dichlorometane (DCM) in air (DCM-A) and in urine (DCM-U) in workplace to confirm a previous report. Male workers in a screen-printing plant participated in the study. Time-weighted average DCM-A was measured by diffusive sampling followed by gas-chromatography (GC), and DCM in end-of-shift urine samples was by head-space GC. The data were subjected to regression and other statistical analyses. In practice, 30 sets of DCM-A and DCM-U values were available. The geometric mean DCM-A was 8.4 ppm and that of DCM-U (as observed) was 41.1 µg/l. The correlation coefficients (0.70-0.85) were statistically significant across the correction for urine density. Thus, the analysis for un-metabolized DCM in end-of-shift urine samples is applicable for biological monitoring of occupational exposure to DCM, in support of and in agreement with the previous report. In conclusion, biological monitoring of occupational DCM exposure is possible by use of analysis for un-metabolized DCM in end-of-shift urine.


Assuntos
Monitoramento Biológico/métodos , Cloreto de Metileno/análise , Cloreto de Metileno/urina , Exposição Ocupacional/análise , Adulto , Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental/métodos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Impressão
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