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1.
Food Funct ; 15(8): 4421-4435, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38563324

RESUMEN

Fu Brick tea belongs to fermented dark tea, which is one of the six categories of tea. Fu Brick tea has been reported to reduce adiposity and has beneficial effects in the treatment of hypercholesterolemia and cardiovascular disease. Theabrownin (TB) is one of the pigments with the most abundant content in Fu Brick tea. TB has also been reported to have lipid-lowering effects, but its mechanism remains unclear. We found that TB could effectively reduce the insulin resistance and fat deposition induced by a high fat diet (HFD), decrease inflammation in the liver, improve intestinal integrity, and reduce endotoxins in circulation. Further studies showed that TB increased the abundance of Verrucomicrobiota and reduced the abundance of Firmicutes and Desulfobacterota in the intestinal tract of obese mice. The alteration of gut microbiota is closely linked to the metabolic phenotype after TB treatment through correlation analysis. Moreover, TB changed the gut microbial metabolites including L-ornithine, α-ketoglutarate, and glutamine, which have also been found to be upregulated in the liver after TB intervention. In vitro, L-ornithine, α-ketoglutarate, or glutamine significantly reduced lipopolysaccharide (LPS)-induced inflammation in macrophages. Therefore, our results suggest that TB can reduce adiposity, systemic insulin resistance, and liver inflammation induced by a HFD through altering gut microbiota and improving the intestinal tight junction integrity. The metabolites of gut microbiota might also play a role in ameliorating the HFD-induced phenotype by TB.


Asunto(s)
Hígado Graso , Microbioma Gastrointestinal , Inflamación , Resistencia a la Insulina , Ratones Endogámicos C57BL , , Animales , Masculino , Ratones , Catequina/farmacología , Dieta Alta en Grasa/efectos adversos , Hígado Graso/tratamiento farmacológico , Hígado Graso/metabolismo , Microbioma Gastrointestinal/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Hígado/metabolismo , Hígado/efectos de los fármacos , Té/química
2.
ACS Appl Mater Interfaces ; 15(2): 3433-3441, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36596273

RESUMEN

Lack of solution processability is the main bottleneck in research progression and commercialization of conducting polymers. The current strategy of employing a water-soluble dopant (such as PEDOT:PSS) is not feasible with organic solvents, thus limiting compatibility on hydrophobic surfaces, such as three-dimensional (3D) printable thermoplastics. In this article, we utilize a colloidal dispersion of PEDOT particles to overcome this limitation and formulate an organic paint demonstrating conformal coating on 3D-printed objects. We start with synthesizing PEDOT particles that possess a low electrical resistance (gap resistance of 4.2 ± 0.5 Ω/mm). A particle-based organic paint is formulated and applied via brush painting. Coated objects show a surface resistance of 1 kΩ/cm, comparable to an object printed by commercial conductive filaments. The coating enables the fabrication of pH and strain sensors. Highly conductive PEDOT particles also absorb light strongly, especially in the near-infrared (NIR) range due to the high concentration of charge carriers on the polymer's conjugated backbones (i.e., polarons and bipolarons). PEDOT converts light to heat efficiently, resulting in a superior photothermal activity that is demonstrated by the flash ignition of a particle-impregnated cotton ball. Consequently, painted 3D prints are highly effective in converting NIR light to heat, and a 5 s exposure to a NIR laser (808 nm, 0.8 mW/cm2) leads to a record high-temperature increase (194.5 °C) among PEDOT-based coatings.

3.
ACS Appl Mater Interfaces ; 15(2): 3235-3243, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36603852

RESUMEN

Conducting polymers rise among some of the most promising transparent supercapacitor electrode materials due to high conductivity, environmental stability, light weight, and ease of synthesis. A major challenge for depositing conducting polymers on a glass substrate is the lack of molecular interactions between organic and inorganic moieties resulting in poor adhesion and low cycling stability of the electrode. We present a synthetic approach by covalently linking poly(3,4-ethylyenedioxythiophene) (PEDOT) and glass through Friedel-Crafts alkylation on a self-assembled diphenyldimethoxysilane monolayer. This method obviates the need for a conductive FTO or ITO coating, enabling the fabrication of current collector-free planar supercapacitor electrodes on any glass surface. The electrode produced from our vapor-phase synthesis is coated with a highly conductive nanofibrillar PEDOT film (sheet resistance 2.1 Ω/□) possessing a gravimetric capacitance of ∼200 F/g. Our PEDOT planar supercapacitor possesses outstanding stability (86% capacitance retention after 50,000 cycles). We also fabricate a proof-of-concept transparent tandem supercapacitor on PEDOT-coated glass using 3D-printed frames that supplies enough voltage and current to light up a blue light-emitting diode (LED).

4.
Opt Express ; 30(20): 35398-35408, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36258492

RESUMEN

Electro-optical modulators are essential for scalable photonic integrated circuits and are promising for many applications. The convergence of silicon (Si) and lithium niobate (LN) allows for a compact device footprint and large-scale integration of modulators. We propose a sandwiched Si/I/LNOI modulator for broad modulation with CMOS-compatible fabrication tolerances. There is a thin film SiO2 spacer sandwiched between Si and LN, which is engineered to tailor optical and electrical properties and enhance index matching. Moreover, the SiO2 spacer is also exploited to inhibit the radiation loss induced by mode coupling. The modulator shows a bandwidth of ∼180 GHz with a halfwave voltage of 3 V. Such a device is considerably robust to the fabrication deviations, making it promising for massive and stable manufacturing.

5.
Environ Sci Pollut Res Int ; 29(48): 72545-72555, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35608764

RESUMEN

Herein, novel composite materials were prepared by intercalating functional pillars, i.e., pentafluorobenzene (PFB) and sodium 2,3,4,5,6-pentafluorobenzoate (PFBS), into graphene oxide (GO) sheets. It led to forming size hives and increased availability of intrinsic area of GO. The synthesized materials (GO-PFB and GO-PFBS) were investigated as adsorbents to eliminate sulfadiazine (SD) from aqueous solutions. The adsorption capacities of GO-PFBS (1002.21 µmol/g) and GO-PFB (564.17 µmol/g) were 6.37 and 3.59 times higher than that of GO (157.21 µmol/g), respectively. The adsorption of SD onto GO-PFBS decreased with increasing solution pH. Density functional theory (DFT) results revealed that the SD adsorption onto the adsorbents was exothermic, and the introduction of the carboxylate groups showed lower binding energy. It was found that hydrophobic interaction fully participates in the adsorption process, and the electrostatic complementation of hydrogen bonding further enhances the SD adsorption. Obtained results showed that intercalating functional rigid molecules as pillars to support GO sheets could improve its adsorption behavior.


Asunto(s)
Grafito , Contaminantes Químicos del Agua , Adsorción , Grafito/química , Preparaciones Farmacéuticas , Sodio , Sulfadiazina , Sulfanilamida , Agua , Contaminantes Químicos del Agua/análisis
6.
Materials (Basel) ; 15(2)2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-35057195

RESUMEN

The quenching condition of aluminum alloy can affect the mechanical property and corrosion resistance of the profile. This paper is aimed at the low quench sensitivity of aluminum alloys. Scanning electron microscopy and transmission electron microscopy were used to analyze precipitate behaviors of the 7A46 aluminum alloy under different isothermal cooling conditions and microstructure evolutions of quench-induced precipitations. The effect of the different isothermal time on the corrosion resistance of the alloy, and the relationship between microstructure and corrosion resistance after quenching were revealed through electrochemical impedance spectroscopy and potentiodynamic polarization tests. Results show that corrosion sensitivity of the quenching-aged alloy is much higher than that of the double-aged (DA) alloy, and the corrosion resistance of the quenched alloy decreases firstly and then increases. Due to the high density of the matrix precipitates, the increased content of the impurity element, the discontinuity of the grain boundary precipitates and the widening of the precipitates free zone, the most serious degree of corrosion performance among the quenched alloys is 295 °C at 800 s, and the self-corrosion potential and self-current density is -0.919 V and 2.371 µA/cm2, respectively.

7.
ACS Cent Sci ; 7(10): 1668-1675, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34729410

RESUMEN

Atmospheric pollution demands the development of solar-driven photocatalytic technologies for the conversion of CO2 into a fuel; state-of-the-art cocatalyst systems demonstrate conversion efficiencies currently unattainable by a single catalyst. Here, we upend the status quo demonstrating that the nanofibrillar conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is a record-breaking single catalyst for the photoreduction of CO2 to CO. This high catalytic efficiency stems from a highly conductive nanofibrillar structure that significantly enhances surface area, CO2 adsorption and light absorption. Moreover, the polymer's band gap is optimized via chemical doping/dedoping treatments using hydrochloric acid, ammonia hydroxide, and hydrazine. The hydrazine-treated PEDOT catalyst exhibits 100% CO yield under a stable regime (>10 h) with a maximum rate of CO evolution (3000 µmol gcat -1 h-1) that is 2 orders of magnitude higher than the top performing single catalyst and surpassed only by three other cocatalyst systems. Nanofibrillar PEDOT provides a new direction for designing the next generation of high-efficiency photoreduction catalysts.

8.
ACS Appl Mater Interfaces ; 13(29): 34671-34678, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34101409

RESUMEN

Atmospheric water harvesting is a promising technology for alleviating global water scarcity. Current water sorption materials efficiently capture water vapor from ubiquitous air; however, they are difficult to scale up due to high costs, complex device engineering, and intensive energy consumption. Fired red brick, a low-cost masonry construction material, holds the potential for developing large-scale functional architectures. Here, we utilize fired red brick for atmospheric water harvesting by integrating a microtubular coating of the conducting polymer PEDOT within its inorganic microstructure. This microtubular polymer coating affords hygroscopicity and high surface area for water nucleation, enables capillary forces to promote water transport, and enhances the water harvesting efficiency. Our brick composite achieves a maximum water vapor uptake of ∼200 wt % versus polymer mass at 95% relative humidity, decreasing to ∼15 wt % at 40% relative humidity. Facile water release is demonstrated via thermal, electrical, and illuminative heating. This proof-of-concept study demonstrates the potential of masonry construction materials for large-scale atmospheric water harvesting.

9.
ACS Nano ; 15(4): 7799-7810, 2021 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-33819007

RESUMEN

Increasing capacitance and energy density is a major challenge in developing supercapacitors for flexible portable electronics. A thick electrode with a high mass loading of active electronic material leads to high areal capacitance; however, the higher the loading, the higher the mechanical stiffness and ion diffusion resistance, thereby hampering development of flexible supercapacitors. Here, we show a chemical strategy that leads to a hierarchical electrode structure producing devices with both an exceedingly high areal capacitance and superior flexibility. We utilize α-Fe2O3 particles as an oxidant precursor for controlling oxidative radical polymerization of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) from the vapor phase. Our approach impregnates carbon cloth with α-Fe2O3 particles prior to monomer vapor exposure, resulting in state-of-the-art flexible nanofibrillar PEDOT supercapacitors possessing high areal capacitance (2243 mF/cm2 for two-electrode vs 6210 mF/cm2 for three-electrode) and high areal energy density (412 µWh/cm2).

10.
Nat Commun ; 11(1): 3882, 2020 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-32782258

RESUMEN

Fired brick is a universal building material, produced by thousand-year-old technology, that throughout history has seldom served any other purpose. Here, we develop a scalable, cost-effective and versatile chemical synthesis using a fired brick to control oxidative radical polymerization and deposition of a nanofibrillar coating of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). A fired brick's open microstructure, mechanical robustness and ~8 wt% α-Fe2O3 content afford an ideal substrate for developing electrochemical PEDOT electrodes and stationary supercapacitors that readily stack into modules. Five-minute epoxy serves as a waterproof case enabling the operation of our supercapacitors while submerged underwater and a gel electrolyte extends cycling stability to 10,000 cycles with ~90% capacitance retention.

11.
ACS Appl Mater Interfaces ; 11(50): 47320-47329, 2019 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-31739664

RESUMEN

Current state-of-the-art synthetic strategies produce conducting polymers suffering from low processability and unstable chemical and/or physical properties stifling research and development. Here, we introduce a platform for synthesizing scalable submicron-sized particles of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). The synthesis is based on a hybrid approach utilizing an aerosol of aqueous oxidant droplets and monomer vapor to engineer a scalable synthetic scheme. This aerosol vapor polymerization technology results in bulk quantities of discrete solid-state submicron particles (750 nm diameter) with the highest reported particle conductivity (330 ± 70 S/cm) so far. Moreover, particles are dispersible in organics and water, obviating the need for surfactants, and remain electrically conductive and doped over a period of months. This enhanced processability and environmental stability enable their incorporation in thermoplastic and cementitious composites for engineering chemoresistive pH and temperature sensors.

12.
Nanoscale ; 11(25): 12358-12369, 2019 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-31215944

RESUMEN

Freestanding, contiguous, and translucent polypyrrole nanonets are prepared within 90 minutes at room temperature in Petri dishes by exposing aqueous oxidant to static pyrrole vapor. The nanonets are 150 nm thick, with variable densities depending on polymerization time. The nanonets maintain a low sheet resistance of 29.1 Ω□-1 at 30% optical transmission, and 423 Ω□-1 at 50% transmission. A mechanism is proposed in which polypyrrole islands serve as nucleation sites for further surface-tension constrained polymerization. The nanonets exhibit a high degree of electrochemical dopability (over 24%). Nets are robust and processable, as evidenced by their ability to drape over 2D and 3D substrates. Large areas of films are manually twisted into highly porous sub-millimeter diameter conductive wires, able to recover their two-dimensional structure upon immersion in solvents. Moreover, nanonets exhibit a high specific capacitance of 518 F g-1 for a 1.2 V potential window. Electrochemical capacitors fabricated with nanonet active electrodes show a high energy density of 9.86 W h kg-1 at 1775 W kg-1 when charged to 0.8 V.

13.
J Biotechnol ; 161(1): 42-8, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-22728423

RESUMEN

Ketogulonicigenium vulgare WSH001 is an industrial strain commonly used in the vitamin C producing industry. In order to acquire a comprehensive understanding of its physiological characteristics, a genome-scale metabolic model of K. vulgare WSH001, iWZ663, including 830 reactions, 649 metabolites, and 663 genes, was reconstructed by genome annotation and literature mining. This model was capable of predicting quantitatively the growth of K. vulgare under L-sorbose fermentation conditions and the results agreed well with experimental data. Furthermore, phenotypic features, such as the defect in sulfate metabolism hampering the syntheses of L-cysteine, L-methionine, coenzyme A (CoA), and glutathione, were investigated and provided an explanation for the poor growth of K. vulgare in monoculture. The model presented here provides a validated platform that can be used to understand and manipulate the phenotype of K. vulgare to further improve 2-KLG production efficiency.


Asunto(s)
Alphaproteobacteria/genética , Alphaproteobacteria/metabolismo , Ácido Ascórbico/biosíntesis , Microbiología Industrial/métodos , Redes y Vías Metabólicas/genética , Modelos Biológicos , Alphaproteobacteria/crecimiento & desarrollo , Redes y Vías Metabólicas/fisiología
14.
Plant Physiol Biochem ; 48(2-3): 142-52, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20060310

RESUMEN

Current research indicated that the resveratrol was mainly accumulated in the skin of grape berry, however, little is yet known about the distribution of resveratrol, as well as the regulation mechanism at protein level and the localization of stilbene synthase (malonyl-CoA:4-coumaroyl-CoA malonyltransferase; EC 2.3.1.95; STS), a key enzyme of resveratrol biosynthesis, in young grape plants (Vitis vinifera L. cv. Cabernet Sauvignon). Resveratrol, whose constitutive level ranged from 0.2 mg kg(-1) FW to 16.5 mg kg(-1) FW, could be detected in stem, axillary bud, shoot tip, petiole, root and leaf of grape plants. Among them, stem phloems presented the most abundant of resveratrol, and the leaves presented the lowest. Interestingly, the level of STS mRNA and protein were highest in grape leaves. And the analysis of immunohistochemical showed the tissue-specific distribution of STS in different organs, presenting the similar results compared with the amount of protein. And the subcellular localization revealed that the cell wall in different tissues processed the most golden particles representing STS. Subjecting to UV-C irradiation, resveratrol and STS were both intensely stimulated in grape leaves, with the similar response pattern. Results above indicated that distribution of resveratrol and STS in grape was organ-specific and tissue-specific. And the accumulation of resveratrol induced by UV-C was regulated by transcriptional and translational level of STS.


Asunto(s)
Aciltransferasas/metabolismo , Proteínas de Plantas/metabolismo , Estructuras de las Plantas/metabolismo , Estilbenos/metabolismo , Vitis/metabolismo , Aciltransferasas/genética , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Estructuras de las Plantas/efectos de la radiación , ARN Mensajero/metabolismo , Resveratrol , Rayos Ultravioleta , Vitis/genética , Vitis/efectos de la radiación
15.
J Plant Physiol ; 167(2): 95-102, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-19716623

RESUMEN

Plants have evolved mechanisms to avoid and repair UV radiation damage, and the free radicals caused by UV tend to be involved in the induction of antioxidant defense systems. In this study, changes in resveratrol and antioxidant enzymes were investigated in relation to UV damage in peanut seedlings. Accumulation of endogenous resveratrol and stilbene synthase mRNA occurred rapidly and significantly in response to UV-C irradiation. Applying resveratrol before UV-C irradiation mitigated rusty spots and wilting of peanut leaves, and inhibition of resveratrol by applying 3,4-methylenedioxycinnamic acid worsened UV-C damage, an effect that was found to be concentration dependent. Correspondingly, the effect of resveratrol on malondialdehyde was similar to changes in the apparent morphology of seedling leaves. Changes in H(2)O(2), O(2)(-), and antioxidant enzymes showed some similarities after either UV-C irradiation or resveratrol treatment. Activities of superoxide dismutases, glutathione reductase, and catalase were more than 2-fold higher during the first 1h after treatments. Ascorbate peroxidase activity increased to more than 3-fold higher 24h after irradiation, whereas it was more than 2-fold higher 8h after resveratrol treatment. Activities of dehydroascorbate reductase and monodehydroascorbate reductase increased by 40% during 8-24h after treatments. Consequently, we proposed that changes in endogenous resveratrol and in antioxidant enzymes may have been involved in oxidative stress induced by UV-C exposure in peanut seedlings.


Asunto(s)
Antioxidantes/metabolismo , Arachis/enzimología , Arachis/metabolismo , Plantones/enzimología , Plantones/metabolismo , Rayos Ultravioleta , Arachis/efectos de los fármacos , Arachis/efectos de la radiación , Catalasa/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/efectos de la radiación , Glutatión Reductasa/metabolismo , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Resveratrol , Plantones/efectos de los fármacos , Plantones/efectos de la radiación , Estilbenos/metabolismo , Estilbenos/farmacocinética , Superóxido Dismutasa/metabolismo
16.
J Integr Plant Biol ; 51(6): 562-73, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19522815

RESUMEN

The role of jasmonic acid (JA) in plant wounding response has been demonstrated. However, the source of JA in wound signaling remains unclear. In the present study, pea seedlings were used as material to investigate the systemic induction of JA and the activation of lipoxygenase (LOX)-dependent octadecanoid pathway upon wounding. The results showed that endogenous JA could induce two peaks in the wounded leaves and the stalks, while only one peak in the systemic leaves. LOX activity and its protein amount were also induced and the stimulation mainly occurred in the late phase, while one peak of induction was present after pretreatment with JA. Applied nordihydroguaiaretic acid (NDGA), an inhibitor of LOX activity, only inhibited the induction of JA in the late phase, and the resistance of pea was impaired. Furthermore, 13(S)-hydroperoxy-9(Z), 11(E)-octadecadienoic acid (13(S)-H(P)ODE) was confirmed to be the main product of LOX throughout the experimental time. In addition, immunocytochemical analysis also revealed the occurrence of JA biosynthesis and transport upon wounding. These results demonstrated that wound-induced JA in wounded leaves resulted from its biosynthesis and conversion from its conjugates, while in systemic leaves resulted from its transport and biosynthesis; and proved that the LOX pathway was vital to the wound-induced defense response involved in JA biosynthesis.


Asunto(s)
Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Pisum sativum/metabolismo , Enfermedades de las Plantas , Plantones/metabolismo , Western Blotting , Ciclopentanos/farmacología , Lipooxigenasa/metabolismo , Malondialdehído/metabolismo , Masoprocol/farmacología , Oxilipinas/farmacología , Pisum sativum/citología , Pisum sativum/enzimología , Pisum sativum/ultraestructura , Plantones/citología , Plantones/enzimología , Plantones/ultraestructura , Factores de Tiempo
17.
Planta ; 229(5): 1087-98, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19225806

RESUMEN

The plasma membrane H(+)-ATPase (PM H(+)-ATPase, EC.3.6.1.35) plays a key role in the plant response to environmental stress. In this study, a possible mechanistic link between the PM H(+)-ATPase and salicylic acid (SA)-induced thermotolerance was investigated in pea (Pisum sativum L. cv. NingXia) leaves. The burst of free SA in response to heat acclimation (38 +/- 0.5 degrees C) was observed, and peaks appeared subsequently both in activity and amount of PM H(+)-ATPase in pea leaves during heat acclimation. Similarly, exogenous SA also triggered the two peaks in the room temperature (25 +/- 0.5 degrees C). Paclobutrazol (PAC) was employed to infiltrate onto pea leaves prior to heat acclimation treatment. The results showed that the peaks of both free SA and activity of PM H(+)-ATPase still occurred after the PAC pretreatment. In acquired thermotolerance assessment (malondialdehyde content and degree of wilting), spraying SA and fusicoccin (FC, the activator of PM H(+)-ATPase) separately could protect pea leaves from heat injury. Results from RT-PCR and western blotting analysis indicated that the increase in activity of the PM H(+)-ATPase was due to its transcriptional and translational regulation. The subcellular localizations of PM H(+)-ATPase after the FC or SA pretreatment also showed that the PM H(+)-ATPase is important to maintain the integrity of plasma membrane against the heat stress. Taken together, these results suggest PM H(+)-ATPase is related to the development of SA-induced thermotolerance in pea leaves.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Membrana Celular/enzimología , Pisum sativum/enzimología , Hojas de la Planta/enzimología , ATPasas de Translocación de Protón/metabolismo , Ácido Salicílico/farmacología , Temperatura , Aclimatación/efectos de los fármacos , Membrana Celular/ultraestructura , Permeabilidad de la Membrana Celular/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Malondialdehído/metabolismo , Pisum sativum/citología , Pisum sativum/efectos de los fármacos , Pisum sativum/ultraestructura , Hojas de la Planta/citología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/ultraestructura , Transporte de Proteínas/efectos de los fármacos , ATPasas de Translocación de Protón/genética , ATPasas de Translocación de Protón/ultraestructura , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estrés Fisiológico/efectos de los fármacos , Fracciones Subcelulares/efectos de los fármacos , Fracciones Subcelulares/enzimología , Triazoles/farmacología
18.
J Exp Bot ; 57(12): 3337-47, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908502

RESUMEN

Increasing evidence suggests that heat acclimation and exogenous salicylic acid (SA) and abscisic acid (ABA) may lead to the enhancement of thermotolerance in plants. In this study, the roles that free SA, conjugated SA, ABA, and phosphatidylinositol-4,5-bisphosphate (PIP(2))-specific phospholipase C (PLC) play in thermotolerance development induced by heat acclimation (38 degrees C) were investigated. To evaluate their potential functions, three inhibitors of synthesis or activity were infiltrated into pea leaves prior to heat acclimation treatment. The results showed that the burst of free SA in response to heat acclimation could be attributed to the conversion of SA 2-O-D-glucose, the main conjugated form of SA, to free SA. Inhibition of ABA biosynthesis also resulted in a defect in the free SA peak during heat acclimation. In acquired thermotolerance assessment, the greatest weakness of antioxidant enzyme activity and the most severe heat injury (malondialdehyde content and degree of wilting) were found in pea leaves pre-treated with neomycin, a well-known inhibitor of PIP(2)-PLC activity. PsPLC gene expression was activated by exogenous ABA, SA treatments, and heat acclimation after pre-treatments with a SA biosynthesis inhibitor. From these results, PIP(2)-PLC appears to play a key role in free SA- and ABA-associated reinforcement of thermotolerance resulting from heat acclimation.


Asunto(s)
Ácido Abscísico/fisiología , Aclimatación , Calor , Hidrolasas Diéster Fosfóricas/fisiología , Pisum sativum/metabolismo , Ácido Salicílico/metabolismo , Ácido Abscísico/antagonistas & inhibidores , Ácido Abscísico/metabolismo , Anisoles/farmacología , Antioxidantes/metabolismo , Benzoatos/metabolismo , Glucosiltransferasas/metabolismo , Glicina/análogos & derivados , Glicina/farmacología , Modelos Biológicos , Neomicina/farmacología , Pisum sativum/efectos de los fármacos , Pisum sativum/fisiología , Fosfoinositido Fosfolipasa C , Hidrolasas Diéster Fosfóricas/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Inhibidores de la Síntesis de la Proteína/farmacología , Ácido Salicílico/antagonistas & inhibidores , Triazoles/farmacología
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