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1.
Acta Pharmacol Sin ; 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931765

RESUMO

LianhuaQingwen capsule, prepared from an herbal combination, is officially recommended as treatment for COVID-19 in China. Of the serial pharmacokinetic investigations we designed to facilitate identifying LianhuaQingwen compounds that are likely to be therapeutically important, the current investigation focused on the component Glycyrrhiza uralensis roots (Gancao). Besides its function in COVID-19 treatment, Gancao is able to induce pseudoaldosteronism by inhibiting renal 11ß-HSD2. Systemic and colon-luminal exposure to Gancao compounds were characterized in volunteers receiving LianhuaQingwen and by in vitro metabolism studies. Access of Gancao compounds to 11ß-HSD2 was characterized using human/rat, in vitro transport, and plasma protein binding studies, while 11ß-HSD2 inhibition was assessed using human kidney microsomes. LianhuaQingwen contained a total of 41 Gancao constituents (0.01-8.56 µmol/day). Although glycyrrhizin (1), licorice saponin G2 (2), and liquiritin/liquiritin apioside (21/22) were the major Gancao constituents in LianhuaQingwen, their poor intestinal absorption and access to colonic microbiota resulted in significant levels of their respective deglycosylated metabolites glycyrrhetic acid (8), 24-hydroxyglycyrrhetic acid (M2D; a new Gancao metabolite), and liquiritigenin (27) in human plasma and feces after dosing. These circulating metabolites were glucuronized/sulfated in the liver and then excreted into bile. Hepatic oxidation of 8 also yielded M2D. Circulating 8 and M2D, having good membrane permeability, could access (via passive tubular reabsorption) and inhibit renal 11ß-HSD2. Collectively, 1 and 2 were metabolically activated to the pseudoaldosterogenic compounds 8 and M2D. This investigation, together with such investigations of other components, has implications for precisely defining therapeutic benefit of LianhuaQingwen and conditions for its safe use.

2.
Pharmacol Res ; 167: 105519, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33636352

RESUMO

Chinese materia medica (CMM) is indispensable component of Traditional Chinese Medicine (TCM) therapy. With the widespread of TCM around the world, the quality control and safe use of CMM become a major concern. This paper introduces the role of ISO standards for industrial development and current development status of CMM standards in ISO/TC 249. Through the comparison of similarities and differences between CMM standards in ISO/TC 249 and pharmacopoeias of main stakeholders, this paper suggests strengthening standard formulation in the following areas to provide more appropriate documents to facilitate the international trade and promote the industrial development of CMM: (1) Develop standards to fill the blanks among the whole industry chain of CMM; (2) Develop standards for new forms of CMM and services; (3) Develop specification and grade standards for CMM with large quantity and high value.

3.
Food Chem ; 339: 127985, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920305

RESUMO

There is limited research focusing on the effects of human gut microbiota on the oral bioaccessibility and intestinal absorption of pesticide residues in food. In the present study, we use a modified setup of the Simulator of the Human Intestinal Microbial Ecosystem for the determination of pesticide residue bioaccessibility in Chaenomeles speciosa, and a Caco-2 cell model of human intestinal absorption. Results showed that gut microbiota played a dual role based their effects on contaminant release and metabolism in the bioaccessibility assay, and Lactobacillus plantarum was one of key bacterial species in the gut microbiota that influenced pesticide stability significantly. The addition of L. plantarum to the system reduced the relative amounts (by 11.40-86.51%) of six pesticides. The interaction between the food matrix and human gut microbiota led to different absorption rates, and the barrier effects increased with an increase in incubation time.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Praguicidas/farmacologia , Rosaceae/química , Bactérias/metabolismo , Células CACO-2 , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/isolamento & purificação , Neonicotinoides/metabolismo , Neonicotinoides/farmacologia , Nitrocompostos/metabolismo , Nitrocompostos/farmacologia , Compostos Organotiofosforados/metabolismo , Compostos Organotiofosforados/farmacologia , Praguicidas/química , Praguicidas/metabolismo , Rosaceae/metabolismo , Tiametoxam/metabolismo , Tiametoxam/farmacologia
4.
Dalton Trans ; 49(44): 15874-15882, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33156304

RESUMO

SnS2 as the promising anode for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) still encounters the undesirable rate performance and cycle stability. Herein, a unique stable structure is developed, where the SnS2 nanocrystals (NCs) are sturdily encapsulated by carbon shells anchored on a reduced graphene oxide (rGO) via the one-pot solvothermal process. The well-controlled carbon shells provide the enduring protection for SnS2 NCs through C-S covalent bonds from the corrosion of electrolyte and pulverization of structure. Moreover, both experimental results and density functional theory (DFT) calculations demonstrate that the carbon protective shell effectively enhances the structure stability and conductivity of the resulting materials. Interestingly, the size of SnS2 NCs and the thickness of carbon shells are accurately controlled by regulating the content of glucose. Aided by the advanced electron/ion transfer kinetics and structure stability, the SnS2-based electrode exhibits desired lithium/sodium storage performance and unprecedented long-term cycling stability (capacity retention of 74.7% after 1000 cycles at 2 A g-1 for LIBs and 102% after 200 cycles at 500 mA g-1 for SIBs). This work develops a method for promoting the practical applications and large-scale production of SnS2 composites for energy storage devices.

5.
Pharmacol Res ; 160: 105074, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32653649

RESUMO

PURPOSE: Traditional Chinese medicine (TCM) has fully engaged and played an essential role in the prevention and treatment of Coronavirus Disease 2019 (COVID-19). This study compares relevant standards on high-frequent Chinese Materia Medicia (CMM) used in this pandemic aiming at reaching a global consensus and ensuring the use of Chinese medicines safely. METHODS: 141 representative Chinese formulas and Chinese Patent Medicines from the National Protocol and the most of Provincial Protocols for controlling COVID-19 in China have been collected to statistical analyze the composition and characteristics of CMM. Among them, the domestic and international standards of 47 varieties with the frequency usage over 10 times were selected to compare their quality requirements in the mainstream pharmacopoeias and international standards. RESULTS: The quality requirements of used CMM for fighting COVID-19 on the terms of overall quality control, marker compounds, and safety indicators showed different patterns in these mainstream pharmacopoeias and international standards. The uniformed and scientific quality standards of CMM were urgently needed to promote global acceptation and trade. CONCLUSIONS: These findings will provide evidence for building unified quality and safety standards that can adapt to the characteristics of CMM and promote international trade, and also will be stated that it is of the highest priority for ISO/TC 249 to formulate high-quality standards that consolidate international consensus to ensure quality and safety of the urgently needed CMM.


Assuntos
Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Medicamentos de Ervas Chinesas/normas , Medicamentos de Ervas Chinesas/uso terapêutico , Materia Medica/normas , Medicina Tradicional Chinesa/normas , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Infecções por Coronavirus/tratamento farmacológico , Composição de Medicamentos , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Materia Medica/efeitos adversos , Materia Medica/uso terapêutico , Segurança do Paciente , Farmacopeias como Assunto , Saúde Pública , Controle de Qualidade
6.
Zhongguo Zhong Yao Za Zhi ; 45(1): 133-141, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32237422

RESUMO

A simple, specific and selective quantitative analysis of multi-components by single marker(QAMS) method for simultaneous determination of anthraquinones and anthraquinone glycosides in Polygonum multiflorum was developed. Four main anthraquinones and its glycosides, emodin, emodin-8-O-ß-D-glucoside, physcion and physcion-8-O-ß-D-glucoside were selected as analytes to evaluate the quality of P. multiflorum. Emodin was used as the internal standard, and the relative correction factors(RCFs) between emodin and the other three anthraquinones were calculated. Comparison of the contents of the four components in 30 batches of P. multiflorum from different regions and 12 batches decoction pieces from different manufacturers by QAMS and external standard method(ESM) showed that there was no significant difference between QAMS and ESM for quantification of the four main components by using relative error results, and the QAMS method was accurate and reliable, and had a good repeatability. In addition, compared with the results calculated by the difference method between total anthraquinone and free anthraquinone in the content determination of P. multiflorum in Chinese Pharmacopoeia, the results of direct determination combined anthraquinone by QAMS were very close to that by measured the external standard method. Therefore, simultaneous quantification of four main anthraquinones by using QAMS is suitable to evaluate the quality of P. multiflorum. Then the optimized assay method of the combined anthraquinone contents showed simple and feasible, which could be replaced and improved the quantification method of the combined anthraquinone in the current Chinese Pharmacopeia.


Assuntos
Antraquinonas/análise , Medicamentos de Ervas Chinesas/análise , Fallopia multiflora/química , Cromatografia Líquida de Alta Pressão , Glucosídeos , Compostos Fitoquímicos/análise
7.
Chemistry ; 26(4): 853-862, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31691394

RESUMO

The Fe-based transition metal oxides are promising anode candidates for lithium storage considering their high specific capacity, low cost, and environmental compatibility. However, the poor electron/ion conductivity and significant volume stress limit their cycle and rate performances. Furthermore, the phenomena of capacity rise and sudden decay for α-Fe2 O3 have appeared in most reports. Here, a uniform micro/nano α-Fe2 O3 nanoaggregate conformably enclosed in an ultrathin N-doped carbon network (denoted as M/N-α-Fe2 O3 @NC) is designed. The M/N porous balls combine the merits of secondary nanoparticles to shorten the Li+ transportation pathways as well as alleviating volume expansion, and primary microballs to stabilize the electrode/electrolyte interface. Furthermore, the ultrathin carbon shell favors fast electron transfer and protects the electrode from electrolyte corrosion. Therefore, the M/N-α-Fe2 O3 @NC electrode delivers an excellent reversible capacity of 901 mA h g-1 with capacity retention up to 94.0 % after 200 cycles at 0.2 A g-1 . Notably, the capacity rise does not happen during cycling. Moreover, the lithium storage mechanism is elucidated by ex situ XRD and HRTEM experiments. It is verified that the reversible phase transformation of α↔γ occurs during the first cycle, whereas only the α-Fe2 O3 phase is reversibly transformed during subsequent cycles. This study offers a simple and scalable strategy for the practical application of high-performance Fe2 O3 electrodes.

8.
Chemosphere ; 231: 538-545, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31151014

RESUMO

Problems with pesticide residues in medicinal and edible plant have received great attention. The dietary exposure risk induced by presence of pesticide residues depends on its release from the food matrix, i.e., its bioaccessibility. The bioaccessibility of pesticide residues in human food is poorly understood and thus, we used in vitro digestive method to measure the bioaccessibility of six pesticides in Chaenomelis speciosa. Results showed that the lower and upper boundary bioaccessibility values of the six pesticides in C. speciosa was 4.26 and 86.52%, and the bioaccessibility varied for the pesticide types and digestion phase. The α-amylase and pancreatin play an important role in vitro bioaccessibility. Our findings suggest that risk assessment studies should be taken into account the pesticide metabolism, and that previous studies may have underestimated pesticide bioaccessibility.


Assuntos
Resíduos de Praguicidas/metabolismo , Praguicidas/metabolismo , Rosaceae/fisiologia , Disponibilidade Biológica , Humanos , Técnicas In Vitro , Resíduos de Praguicidas/química , Resíduos de Praguicidas/toxicidade , Praguicidas/toxicidade , Medição de Risco
9.
J Dig Dis ; 20(6): 278-287, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31090180

RESUMO

OBJECTIVES: Peptest is a new non-invasive reflux diagnostic test based on lateral flow technology that containing two highly specific human pepsin monoclonal antibodies for detecting pepsin, a biomarker for reflux disease. The primary aim of this multicenter clinical study was to validate the efficacy of Peptest in patients diagnosed with gastroesophageal reflux and healthy controls in China. METHODS: Patients with suspected gastroesophageal reflux underwent an endoscopy and were classified into non-erosive reflux disease and erosive esophagitis subgroups. A healthy control group was also recruited. All participants were given a reflux disease questionnaire-patients scoring greater than 12 and controls scoring zero. All participants provided a postprandial saliva sample and most patients gave an additional post-symptom sample for pepsin analysis. RESULTS: Altogether 1032 participants aged between 19 and 78 years were recruited. They consisted of 488 patients with non-erosive reflux disease, 221 with erosive esophagitis and 323 healthy controls. The number of postprandial and post-symptom samples analyzed totaled 1031 and 692, respectively. The results across all centers showed an overall pepsin-positive sensitivity of 85%, a specificity of 60%, a positive predictive value of 82%, a negative predictive value of 65% and a positive likelihood ratio of 2.12. CONCLUSION: The sensitivity of Peptest was high, but the specificity achieved in some centers was low, resulting overall in only a moderate specificity. Further diagnostic investigative studies are warranted.


Assuntos
Anticorpos Monoclonais/análise , Refluxo Gastroesofágico/diagnóstico , Pepsina A/imunologia , Adulto , Idoso , Anticorpos Monoclonais/imunologia , Biomarcadores/análise , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Saliva/química , Sensibilidade e Especificidade , Adulto Jovem
10.
Food Funct ; 10(1): 289-295, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30566153

RESUMO

Humans are frequently exposed to the residues of various neonicotinoids, highlighting the need to understand human exposure through oral ingestion of contaminated foods. In this study, the effects of different food matrices (tomato, cucumber, and carrot) and their interaction with dietary component additives, including proteins and dietary fiber, was investigated. The results showed that the presence of a food matrix had a significant effect on the bioaccessibility of neonicotinoids (imidacloprid, thiamethoxam, acetamiprid, and thiacloprid) in both the gastric and intestinal environments. Neonicotinoids in tomato presented relatively low bioaccessibility, indicating that the daily intake of the tomato can be regarded as being relatively safer. Moreover, the addition of protein or dietary fiber to fruit and vegetables had a marked influence on neonicotinoid bioaccessibility and the effects varied between the different matrices. In particular, the addition of 2.0% dietary fiber significantly reduced the bioaccessibility (18.38-67.91%). Therefore, we recommend that consuming an increased intake of dietary fiber could improve the safety of fruit and vegetables in daily life. The present results can support the identification of suitable food intake conditions for the significant reduction of pesticide residue levels.


Assuntos
Frutas/química , Resíduos de Praguicidas/química , Verduras/química , Cucumis sativus/química , Cucumis sativus/metabolismo , Daucus carota/química , Daucus carota/metabolismo , Digestão , Contaminação de Alimentos/análise , Frutas/metabolismo , Humanos , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Neonicotinoides/metabolismo , Resíduos de Praguicidas/metabolismo , Verduras/metabolismo
11.
Nanoscale ; 10(40): 18942-18948, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30303226

RESUMO

A three-dimensional hierarchical Ni3Se2 nanorod array (NA) grown in situ on foam Ni is the first to act as a carbon/binder-free electrode of SIBs via a one-step reversible conversion reaction. By a special decomposition-fusion process, the morphology and composition of the NA are regulated to obtain ultrahigh areal capacity, which is three times greater than that reported for other metal selenides.

12.
J Nat Prod ; 81(7): 1508-1516, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-29924604

RESUMO

Twelve new abietane diterpenoids (1-12) and 31 known analogues (13-43) were isolated from a medicinal Chinese herb, Clerodendrum trichotomum Thunberg. The absolute configurations of 1-3 were established on the basis of ECD and X-ray crystallography data, whereas that of 4 was elucidated by comparison of experimental and calculated ECD data. Eight diterpenoids, 15,16-dehydroteuvincenone G (1), trichotomin A (4), 2α-hydrocaryopincaolide F (7), villosin C (20), 15-dehydro-17-hydroxycyrtophyllone A (22), demethylcryptojaponol (38), 6ß-hydroxydemethylcryptojaponol (39), and trichotomone (43), exerted inhibitory effects against NO production with IC50 values of 5.6-16.1 µM. The structure-activity relationships of the isolated diterpenoids are also estimated.


Assuntos
Abietanos/isolamento & purificação , Clerodendrum/química , Medicamentos de Ervas Chinesas/farmacologia , Óxido Nítrico/antagonistas & inibidores , Abietanos/química , Abietanos/farmacologia , Animais , Cristalografia por Raios X , Medicamentos de Ervas Chinesas/isolamento & purificação , Camundongos , Estrutura Molecular , Raízes de Plantas/química , Células RAW 264.7 , Relação Estrutura-Atividade
13.
Artigo em Inglês | MEDLINE | ID: mdl-29762491

RESUMO

Estimating the influence of bioaccessibility of pesticide residues in fruits and vegetables on dietary exposure is a challenge for human health risk assessment. This study investigated the bioaccessibility of pesticide residues in cherry tomatoes and contributing factors (digestion time, pH, solid/liquid ratio, and dietary nutrition) using an in vitro test simulating the human gastrointestinal tract. pH had the largest effect on triazolone precipitation in the simulated gastric intestinal juice, which had a significant impact on the bioaccessibility. The bioaccessibility of triazolone in the intestinal stage was slightly higher than that in the stomach stage, owing to bile salts and pancreatic enzymes present in the intestinal juice. The bioaccessibility of triazolone did not change significantly with digestion time. In the gastric stage, there was a logarithmic relationship between the bioaccessibility and solid/liquid ratio (R² = 0.9941). The addition of oil significantly changed the bioaccessibility in the gastrointestinal stage. Protein and dietary fiber only affected bioaccessibility in the stomach stage. Dietary nutrition can reduce the release of pesticides from fruits and vegetables into the stomach, sharply reducing the bioaccessibility, and the dietary exposure of pesticide residues in fruits and vegetables can be properly evaluated.


Assuntos
Disponibilidade Biológica , Trato Gastrointestinal/metabolismo , Lycopersicon esculentum/química , Modelos Biológicos , Resíduos de Praguicidas/metabolismo , Praguicidas/metabolismo , Humanos , Estado Nutricional , Resíduos de Praguicidas/isolamento & purificação , Praguicidas/isolamento & purificação , Medição de Risco
14.
Chemistry ; 24(26): 6798-6803, 2018 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-29575314

RESUMO

A new hexadecahedron assembled by core-shell CoS2 particles@N-doped carbon (CoS2 @NCH) is prepared successfully through the self-templating method. The CoS2 @NCH hybrid electrode delivers a high lithium-storage capacity of 778 mA h g-1 after 1000 cycles at a high current density of 1 A g-1 , which is the longest cycle lifespan among the reported CoS2 anode materials in lithium-ion batteries. Furthermore, the CoS2 @NCH hybrid electrode shows excellent rate capability with a discharge capacity of 220 mA h g-1 at an extremely high current density of 20 A g-1 , and a charge capacity of 649 mA h g-1 is restored upon returning the current density back to 2 A g-1 . The superior performance is attributed to the unique construction of CoS2 @NCH. The N-doped interconnected porous carbon shells form highly conductive skeletons for quick electron transfer and prevent the electrode from collapsing. Moreover, the porous characteristic of the materials plays a key role: as some effective channels, the mesopores on the porous carbon shells provide greater access for lithium, and the mesopores derived from the particle interspace enables the complete immersion of the electrodes in electrolyte, which alleviates the volume expansion and ensures the integrity of the electrode. In addition, the nanosized CoS2 particles, which shorten the ion-transport path and provide extra electroactive sites, also improve the reaction kinetics.

15.
Molecules ; 23(4)2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29596356

RESUMO

In order to ensure raw consumption safety the dissipation behavior, migration, postharvest processing, and dietary risk assessment of five pyrethroids in mushroom (Auricularia polytricha Mont.) cultivated under Chinese greenhouse-field conditions. Half-lives (t1/2) of pyrethroids in fruiting body and substrate samples were 3.10-5.26 and 17.46-40.06 d, respectively. Fenpropathrin dissipated rapidly in fruiting bodies (t1/2 3.10 d); bifenthrin had the longest t1/2. At harvest, pyrethroid residues in A. polytricha (except fenpropathrin) were above the respective maximum residue limits (MRLs). Some migration of lambda-cyhalothrin was observed in the substrate-fruit body system. In postharvest-processing, sun-drying and soaking reduced pyrethroid residues by 25-83%. We therefore recommend that consumers soak these mushrooms in 0.5% NaHCO3 at 50 °C for 90 min. Pyrethroids exhibit a particularly low PF value of 0.08-0.13%, resulting in a negligible exposure risk upon mushroom consumption. This study provides guidance for the safe application of pyrethroids to edible fungi, and for the establishment of MRLs in mushrooms to reduce pesticide exposure in humans.


Assuntos
Basidiomycota , Análise de Alimentos , Piretrinas , Basidiomycota/química , Basidiomycota/metabolismo , Piretrinas/análise , Piretrinas/metabolismo
16.
ACS Appl Mater Interfaces ; 10(1): 509-516, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29243916

RESUMO

A three-layered cathode structure was designed to minimize the shuttle effect of polysulfides and improve active material utilization. The three-layered configuration was fabricated by directly dropping pure sulfur composite slurry into multifunctional dual-barrier layers consisting of a self-standing TiO2/C interlayer and a very thin acetylene black layer (0.35 mg cm-2). In consequence, a decent discharge capacity of 963 mA h g-1 was acquired after 100 cycles at 0.1 C. With cycling at 0.1, 0.2, 0.5, 1, and 2 C, the cells displayed excellent reversible capacities of 1203, 1145, 1035, 934, and 820 mA h g-1, respectively. Furthermore, the cells still delivered a satisfactory discharge capacity of 799 mA h g-1 after 300 cycles at 0.5 C. The light mass of the three-layered configuration guarantees that the energy density is effectively improved, considering the overall mass of the cathode. The energy density (603 W h kg-1 after 100 cycles) was at a high level compared with those of the reported ones. Therefore, it is believed that the synergistic design for the three-layered cathode structure, which combines the mass-produced layer-by-layer structure, provides a novel protocol to the practical application of lithium-sulfur batteries.

17.
Zhongguo Zhong Yao Za Zhi ; 42(21): 4150-4153, 2017 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-29271153

RESUMO

The chemical constituents of Plantaginis Semen with hypoglycemic effect was investigated in this paper. The previous results of the in vivo hypoglycemic effect showed that 60% ethanol extract of Plantaginis Semen decreased the levels of FBG and improved the glucose tolerance in high fat diet(HFD)-induced diabetic C57BL/6 mice. Then, in the present study, the above potential bioactive extract was separated and purified by silica gel, ODS, Sephadex LH-20 column chromatography, medium pressure liquid chromatography(MPLC)and preparative HPLC. The structures of isolated compounds were identified by physicochemical properties and spectral analyses. Eight compounds were obtained and identified as 4, 4a, 5, 7a-tetrahydro-7-(hydroxymethyl)cyclopenta[c]pyran-3(1H)-one(1), iridolactone(2), pedicularislacton(3), rehmaglutin C(4), geniposidic acid(5), p-hydroxylphenylglycerol(6), 1, 2-benzenediol-4-(2-hydroxyethyl)(7), and 3-buten-2-one-4-[3-(ß-D-glucopyranosyloxy)-4-hydroxyphenyl](8). Among them, compounds 1-5 were iridoids, and 6-8 were phenolic acids. Compound 1 was a new natural product, and compounds 2-4, 6 and 8 were isolated from the Plantaginaceae family for the first time.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hipoglicemiantes/farmacologia , Plantago/química , Sementes/química , Animais , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Experimental/tratamento farmacológico , Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/farmacologia , Iridoides/isolamento & purificação , Iridoides/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-28973970

RESUMO

The transfer of pesticide residues from herbal teas to their infusion is a subject of particular interest. In this study, a multi-residue analytical method for the determination of pyrethroids (fenpropathrin, beta-cypermethrin, lambda-cyhalothrin, and fenvalerate) in honeysuckle, chrysanthemum, wolfberry, and licorice and their infusion samples was validated. The transfer of pyrethroid residues from tea to infusion was investigated at different water temperatures, tea/water ratios, and infusion intervals/times. The results show that low amounts (0-6.70%) of pyrethroids were transferred under the different tea brewing conditions examined, indicating that the infusion process reduced the pyrethroid content in the extracted liquid by over 90%. Similar results were obtained for the different tea varieties, and pesticides with high water solubility and low octanol-water partition coefficients (log Kow) exhibited high transfer rates. Moreover, the estimated values of the exposure risk to the pyrethroids were in the range of 0.0022-0.33, indicating that the daily intake of the four pyrethroid residues from herbal tea can be regarded as safe. The present results can support the identification of suitable tea brewing conditions for significantly reducing the pesticide residue levels in the infusion.


Assuntos
Resíduos de Praguicidas/química , Praguicidas/química , Piretrinas/química , Chás de Ervas/análise , Solubilidade
19.
J Agric Food Chem ; 65(41): 9139-9146, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28915046

RESUMO

This study examined how gastrointestinal conditions affect pesticide bioaccessibility and intestinal transepithelial transport of pesticides (difenoconazole, hexaconazole, and spirodiclofen) in humans. We used an in vitro model combining human gastric and intestinal digestion, followed with Caco-2 cell model for human intestinal absorption. Bioaccessibility of three tested pesticides ranged from 25.2 to 76.3% and 10.6 to 79.63% in the gastric and intestinal phases, respectively. A marked trend similar to the normal distribution was observed between bioaccessibility and pH, with highest values observed at pH 2.12 in gastric juice. No significant differences were observed with increasing digestion time; however, a significant negative correlation was observed with the solid-liquid (S/L) ratio, following a logarithmic equation. R2 ranged from 0.9198 to 0.9848 and 0.9526 to 0.9951 in the simulated gastric and intestinal juices, respectively, suggesting that the S/L ratio is also a major factor affecting bioaccessibility. Moreover, significant dose- and time-response effects were subsequently observed for intestinal membrane permeability of difenoconazole, but not for hexaconazole or spirodiclofen. This is the first study to demonstrate the uptake of pesticides by human intestinal cells, aiding quantification of the likely effects on human health and highlighting the importance of considering bioaccessibility in studies of dietary exposure to pesticide residues.


Assuntos
4-Butirolactona/análogos & derivados , Dioxolanos/metabolismo , Resíduos de Praguicidas/metabolismo , Compostos de Espiro/metabolismo , Triazóis/metabolismo , 4-Butirolactona/química , 4-Butirolactona/metabolismo , Transporte Biológico , Células CACO-2 , Permeabilidade da Membrana Celular , Digestão , Dioxolanos/química , Humanos , Mucosa Intestinal/metabolismo , Intestinos/química , Cinética , Resíduos de Praguicidas/química , Compostos de Espiro/química , Triazóis/química
20.
Artigo em Inglês | MEDLINE | ID: mdl-28885583

RESUMO

The migration and accumulation of octachlorodipropyl ether (OCDPE) in soil-tea systems were investigated using a gas chromatography-electron capture detector (GC-ECD) method in young and old tea gardens. When the residual concentration of OCDPE was 100 g a.i. hm-2 in soils, the peak concentrations of OCDPE in fresh leaves of young and old tea plants were 0.365 mg/kg and 0.144 mg/kg, taking 45 days and 55 days, respectively. Equations for the accumulation curves of OCDPE in fresh leaves of young and old tea plants were Ct = 0.0227e0.0566t (R² = 0.9154) and Ct = 0.0298e-0.0306t (R² = 0.7156), and were Ct = 3.8435e0.055t (R² = 0.9698) and Ct = 1.5627e-0.048t (R² = 0.9634) for dissipation curves, with a half-life of 14.4 days and 12.6 days, respectively. These results have practical guiding significance for controlling tea food safety.


Assuntos
Camellia sinensis/metabolismo , Éteres/análise , Sinergistas de Praguicidas/análise , Folhas de Planta/metabolismo , Poluentes do Solo/análise , Cromatografia Gasosa , Monitoramento Ambiental , Éteres/metabolismo , Inocuidade dos Alimentos , Jardins , Meia-Vida , Sinergistas de Praguicidas/metabolismo , Poluentes do Solo/metabolismo
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