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A novel fluorescent sensor was developed in this study based on glutathione-functionalized graphene quantum dots (GQDs@GSH) to detect organophosphorus pesticide residues in Radix Angelica Sinensis. GQDs@GSH was synthesized by a one-step pyrolysis method with a fluorescence quantum yield as high as 33.9% and its structure was characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. GQDs@GSH exhibited excellent fluorescence property showing strong blue fluorescence under UV irradiation. The fluorescence of GQDs@GSH could be quenched by Fe3+ by electron transfer and the quenched fluorescence could be recovered due to the strong chelating and reducing ability of phytic acid (PA). Under the catalyzation of acetylcholinesterase (AChE) and choline oxidase (ChOx), acetylcholine (ACh) could be decomposed to H2O2, which could further oxidize Fe2+ to Fe3+ thus quenching the fluorescence of GQDs@GSH once again. Coumaphos, a kind of organophosphorus pesticide, could inhibit AChE activity, thus making the quenched fluorescence turn on again. Several parameters influencing the fluorescence response such as Fe3+, PA, ACh and coumaphos concentration, pH value and reaction time were optimized. Based on such a fluorescence "off-on-off-on" ngkmechanism, GQDs@GSH was successfully applied to the detection of coumaphos in Radix Angelica Sinensis. A good linear relationship between the fluorescence intensity and coumaphos concentration was obtained in the range of 0.1-10.0 µmol·L-1. By a standard addition method, the recoveries were measured to be 101.44-117.90% with RSDs lower than 1.98%. The biosensor system is simple, sensitive and accurate. It has a good application prospect in the detection of organophosphorus pesticide residues in traditional Chinese medicine and agricultural products, and also expanded the application scope for glutathione as a highly selective biological molecule.
Asunto(s)
Angelica sinensis , Grafito , Residuos de Plaguicidas , Plaguicidas , Puntos Cuánticos , Puntos Cuánticos/química , Grafito/química , Colorantes Fluorescentes/química , Compuestos Organofosforados , Acetilcolinesterasa , Peróxido de Hidrógeno , Cumafos , Glutatión/químicaRESUMEN
Magnetic tunnel junction (MTJ) with magnesium oxide (MgO) tunnel barrier is the core element of spin transfer torque-based magnetic random access memory. For the application in the space environment, the total ionizing dose radiation effects on MTJs need to be evaluated. In this work, the MTJs were exposed to X-ray radiation with different doses of up to 10 Mrad(Si). Measurements of current induced magnetization switching (CIMS) behavior of these MTJs were performed before and after radiation. The results show negligible changes in the tunneling magnetoresistance and current switching properties after 8 Mrad(Si) X-ray radiation. However, with a total dose of 9 Mrad(Si), a significant reduction in junction resistance of a fairly large number of MTJs was observed, which showed characteristics of MTJ breakdown. Moreover, in this study, all experimental MTJs became functionally disabled due to MgO breakdown under 10 Mrad(Si) X-ray radiation. The CoFeB/MgO/CoFeB interface microstructure was observed using X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy (HRTEM). Interfacial structural results indicate that the MgO degradation and breakdown behavior caused by X-ray ionizing radiation can give rise to radiation-induced oxygen vacancies across the tunnel barrier oxide layer.
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Attapulgite(ATP), as a fertilizer slow-release agent and soil conditioner, has shown remarkable effect in improving the utilization rate of fertilizer and the yield and quality of agricultural products and Chinese medicinal materials. This study aims to explore the effect of ATP on the growth and root quality of Angelica sinensis. To be specific, Mingui 1 was used, and through the pot(soil culture) experiment in the Dao-di producing area, the effects of conventional chemical fertilizer added with ATP on the morphology, photosynthesis, soil respiration, and content of ferulic acid and volatile oil in roots of Mingui 1 were detected. The underlying mechanism was discussed from the perspective of source-sink relationship. The results showed that ATP, via the fertilizer slow-release effect, could meet the needs of A. sinensis for nutrients at the root expansion stage, improve the net photosynthetic rate of leaves and aboveground biomass of plants, and promote the transfer and accumulation of nutrients from the aboveground part(source) to the underground root(sink) in advance during the dry matter accumulation period of roots, so as to improve the root weight per plant. ATP can increase the content of total ferulic acid(the sum of free ferulic acid and coniferyl ferulate), the main effective component of Angelicae Sinensis Radix, by promoting the synthesis of ferulic acid in the roots and the transformation to coniferyl ferulate. However, it had little effect on the content of volatile oil. ATP had certain influence on soil respiration, which needs to be further explored from root activity, rhizosphere microorganisms, and soil microorganisms. This study can lay a basis for soil remediation and improvement and ecological cultivation of A. sinensis.
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Angelica sinensis , Aceites Volátiles , Adenosina Trifosfato , Angelica sinensis/química , Ácidos Cumáricos , Fertilizantes/análisis , Compuestos de Magnesio , Aceites Volátiles/química , Raíces de Plantas/química , Compuestos de Silicona , SueloRESUMEN
The research status and development trend of nanotoxicology of Liliaceae medicinal plants were analyzed. In the research, the toxicology of Liliaceae medicinal plants was investigated by the preparation method of silver nanoparticles. By means of spectral curve experiment, the present situation of nanotoxicology of Liliaceae medicinal plants was analyzed, and then its subsequent development trend was analyzed. In this process, Liliaceae medicinal plants could be used effectively, which could create great economic benefits. In the application of the above scheme, the toxicological degradation of Liliaceae medicinal plants could be controlled at about 96%. The high-dose silver nanoparticles could reach 100 µM, and the silver nitrate could reach 10 or 30 µM.
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Liliaceae , Nanopartículas del Metal , Plantas Medicinales , Nanopartículas del Metal/toxicidad , Plata/toxicidadRESUMEN
The medicinal plants with roots and rhizomes as the medicinal parts account for about 1/3 of Chinese medicinal herbs. Root and rhizome medicinal materials are widely used in clinical practice, whereas their wild resource reserves are insufficient to meet the market demand. With the expansion of planting areas, the formation of large-scale production areas, and the increase in planting years, diseases and insect pests of these medicinal plants, which are diverse and have broad transmission routes, strong concealment, and heavy damage, have become more and more serious. The prevention and control of these diseases and insect pests is characterized by multiple ways of pesticide application, large consumption of pesticides, susceptibility to soil barrier, difficulty in the control, and unstable control efficiency. Organophosphorus pesticides(OPPs) are widely used in the cultivation of Chinese medicinal plants because of their diverse varieties, broad-spectrum, good efficacy, and low residues, and have a positive effect on the yield and quality of Chinese medicinal materials. However, the abuse of OPPs not only increases the planting cost, but also affects the quality and safety of Chinese medicinal plants, the safety of clinical use of Chinese medicine, and the ecological safety of production areas. This paper reviewed the research and development progress of OPPs, the registration status of OPPs used in root and rhizome medicinal materials, residue limit standards, residue status, and rapid detection technology progress of OPPs. This review aims to provide research ideas and references for standardizing the use of OPPs in root and rhizome medicinal materials, reducing OPP residues, and establishing a fast, efficient, accurate, and reliable method for the detection of OPP residues in Chinese herbal medicine.
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Residuos de Plaguicidas , Plaguicidas , Plantas Medicinales , Compuestos Organofosforados , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Rizoma/químicaRESUMEN
The long-term and extensive use of chemical fertilizers and pesticides in the cultivation of Chinese materia medica has resulted in serious soil ecological and environmental problems such as secondary salinization, soil consolidation, soil acidification, continuous cropping obstacles, micro-ecological imbalance, and serious soil pests and diseases in the production areas of Chinese materia medica. Therefore, promoting the ecological planting of Chinese materia medica is the only way for the production of Chinese materia medica. Attapulgite(ATP) is a kind of water-rich magnesium-rich aluminosilicate clay mineral with layered and chain structure. It has abundant reserves in China, possesses nano-material properties, strong adsorption and ion exchange properties, and has huge high value utilization space. ATP and its functional products have the potential of water and fertilizer conservation, regulating soil structure and micro-ecology, and are widely used in ecological planting of Chinese materia medica. This paper reviews the resource distribution, structural characteristics, the research and application progress in soil ecological effects of ATP, and prospects the application prospects of it in the ecological planting of Chinese materia medica.
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Medicamentos Herbarios Chinos , Materia Medica , China , Compuestos de Magnesio , Medicina Tradicional China , Compuestos de Silicona , SueloRESUMEN
Codonopsis pilosula (Franch.) Nannf. is a traditional Chinese herbal medicinal plant and a low-cost succedaneum for Panax ginseng and contains various bioactivity components. In this work, we first evaluated the effects of the inoculation of the plant growth-promoting rhizobacteria Bacillus amyloliquefaciens strain GB03 on growth and metabolite accumulation of C. pilosula. The results demonstrated that application of B. amyloliquefaciens GB03 significantly improved the growth of C. pilosula compared to DH5α, Luria broth medium, and water treatment, respectively. On the other hand, we observed that the content of lobetyolin, one of the most important secondary metabolites in C. pilosula, was obviously improved by inoculation of GB03 and almost reached twice that compared to the other three treatments. In addition, some amino acids of roots were elevated by GB03, although not significantly. In conclusion, B. amyloliquefaciens GB03 could induce positive effects on the growth and further stimulate accumulation of secondary metabolites in C. pilosula.
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Inoculantes Agrícolas , Bacillus amyloliquefaciens/fisiología , Codonopsis/metabolismo , Codonopsis/microbiología , Codonopsis/crecimiento & desarrollo , Medicamentos Herbarios Chinos , Fotosíntesis , Plantas Medicinales/crecimiento & desarrollo , Plantas Medicinales/metabolismo , Plantas Medicinales/microbiología , Poliinos/metabolismo , Metabolismo SecundarioRESUMEN
4-coumarate coenzyme A ligase is a key enzyme of phenylpropanoid metabolic pathway in higher plant and may regulate the biosynthesis of ferulic acid in Angelica sinensis. In this study, the homology-based cloning and rapid amplification of cDNA ends (RACE) technique were used to clone a full length cDNA encoding 4-coumarate coenzyme A ligase gene (4CL), and then qRT-PCR was taken for analyzing 4CL gene expression levels in the root, stem and root tissue at different growth stages of seedlings of A. sinensis. The results showed that a full-length 4CL cDNA (1,815 bp) was obtained (GenBank accession number: KT880508) which shares an open reading frame (ORF) of 1 632 bp, encodes 544 amino acid polypeptides. We found 4CL gene was expressed in all tissues including leaf, stem and root of seedlings of A. sinensis. The expressions in the leave and stem were increased significantly with the growth of seedlings of A. sinensis (P < 0.05), while it in the root showed little change. It indicates a time-space pattern of 4CL gene expression in seedlings of A. sinensis. These findings will be useful for establishing an experiment basis for studying the structure and function of 4CL gene and elucidating mechanism of ferulic acid biosynthesis and space-time regulation in A. sinensis.
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Angelica sinensis/genética , Clonación Molecular , Coenzima A Ligasas/genética , Secuencia de Aminoácidos , Secuencia de Bases , ADN Complementario/química , Datos de Secuencia MolecularRESUMEN
OBJECTIVE: To investigate the effects of conjunctive application of Chinese herbal medicine residue compost (CHMRC) and chemical fertilizer on ferulic acid and ligustilide contents in Angelica sinensis. METHODS: There were six treatments, viz. T1: control (no fertilizer), T2: chemical fertilizer (the fertilizer rates for N, P2O5 and K2O were 90, 90 and 60 kg/hm2, respectively), T3:1 350 kg/hm2 CHMRC, 86 kg/hm2N, 84 kg/hm2 P2O5 and 52 kg/hm2 K2O, T4:2 250 kg/hm2 CHMRC, 83 kg/hm2N, 81 kg/hm2 P2O5 and 47 kg/hm2 K2O, T5: 3 150 kg/hm2 CHMRC, 82 kg/hm2N, 77 kg/hm2 P2O5 and 42 kg/hm2 K2O, and T6: CHMRC at 4 500 kg/hm2 (nitrogen application rate was the same as T2). RESULTS: Along with growth stages, the changing trend of ferulic acid and ligustilide contents from all treatments showed a "J"-shaped curve; Ferulic acid and ligustilide contents in the roots at the harvest were increased compared with the beginning by over 16.0% and 117.0%, respectively, in which the maximum increasing rates of ferulic acid and ligustilide contents occurred in the chemical fertilizer treatment (T2), and reached at 68.4% and 176.6%, respectively; Compared with control, T2, T5 and T6 significantly increased ferulic acid content by 19.2% - 25.6%, and ligustilide content by 9.1% - 11.2% (P < 0.05). CONCLUSION: The results are obtained as following: the application of CHMRC and/or chemical fertilizer does not change the chemical composition in the root of Angelica sinensis, but has some effects on the content of related ingredients. This research indicates that T5 should be recommended for Angelica sinensis growing, which will ensure a production of high quality, low cost and environment-friendly.
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4-Butirolactona/análogos & derivados , Angelica sinensis/química , Ácidos Cumáricos/análisis , Fertilizantes , Residuos Industriales/análisis , 4-Butirolactona/análisis , Agricultura/métodos , Angelica sinensis/crecimiento & desarrollo , Angelica sinensis/metabolismo , Biomasa , Cromatografía Líquida de Alta Presión , Nitrógeno/análisis , Nitrógeno/metabolismo , Fósforo/análisis , Fósforo/metabolismo , Raíces de Plantas/química , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Tallos de la Planta/química , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/metabolismo , Potasio/análisis , Potasio/metabolismo , Estaciones del AñoRESUMEN
OBJECTIVE: To study the physiological and biochemical changes during storage of angelica seeds with different moisture contents. METHOD: The dynamic changes of percentage and index of seeds germination, relative conductivity, superoxide dismutase (SOD) activity, contents of soluble sugar and protein were determined at an interval of every two months. RESULT: Under the conditions stored in sealed paper cups at 15 degrees C for 10 months, the germination percentage of angelica seeds with 2.85% of moisture content was kept above 85%. With moisture content reducing, the increase rate of relative conductivity decreased, the down trend of SOD activity and protein content were weakened, and soluble sugar content kept stable. CONCLUSION: In cool conditions, a modest low moisture content of seeds can be beneficial to prolong the longevity of angelica seeds, while high moisture content will accelerate the deterioration process of the seeds.