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Frederic Lapeyrie - One of the best experts on this subject based on the ideXlab platform.
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The indole alkaloids brucine, yohimbine, and hypaphorine are indole-3-acetic Acid-specific competitors which do not alter auxin transport.
Physiologia Plantarum, 2004Co-Authors: Anne Jambois, Alain Delbarre, Franck Anicet Ditengou, Tomonori Kawano, Frederic LapeyrieAbstract:The indole alkaloids brucine and yohimbine, just like hypaphorine, counteract indole-3-acetic Acid (IAA) activity in seedling roots, root hairs and shoots, but do not appear to alter auxin transport in roots or in cultured cells. In roots, the interactions between IAA and these three alkaloids appear competitive and specific since these molecules interact with IAA but with neither 1-Naphthaleneacetic Acid (NAA) or 2,4-dichlorophenoxyacetic Acid (2,4-D), two synthetic auxins. The data reported further support the hypothesis that hypaphorine brucine and yohimbine compete with IAA on some auxin-binding proteins likely to be auxin receptors and that 2,4-D and NAA are not always perceived by the same receptor as IAA or the same component of that receptor. At certain steps of plant development and in certain cells, endogenous indole alkaloids could be involved in IAA activity regulation together with other well-described mechanisms such as conjugation or degradation. Hypaphorine with other active indole alkaloids remaining to be identified, might be regarded as a new class of IAA antagonists.
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hypaphorine from the ectomycorrhizal fungus pisolithus tinctorius counteracts activities of indole 3 acetic Acid and ethylene but not synthetic auxins in eucalypt seedlings
Molecular Plant-microbe Interactions, 2000Co-Authors: Franck Anicet Ditengou, Frederic LapeyrieAbstract:Very little is known about the molecules regulating the interaction between plants and ectomycorrhizal fungi during root colonization. The role of fungal auxin in ectomycorrhiza has repeatedly been suggested and questioned, suggesting that, if fungal auxin controls some steps of colonized root development, its activity might be tightly controlled in time and in space by plant and/or fungal regulatory mechanisms. We demonstrate that fungal hypaphorine, the betaine of tryptophan, counteracts the activity of indole-3-acetic Acid (IAA) on eucalypt tap root elongation but does not affect the activity of the IAA analogs 2,4-D ((2,4-dichlorophenoxy)acetic Acid) or NAA (1-Naphthaleneacetic Acid). These data suggest that IAA and hypaphorine interact during the very early steps of the IAA perception or signal transduction pathway. Furthermore, while seedling treatment with 1-amincocyclopro-pane-1-carboxylic Acid (ACC), the precursor of ethylene, results in formation of a hypocotyl apical hook, hypaphorine applicati...
Fengxia Qiao - One of the best experts on this subject based on the ideXlab platform.
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ionic liquid organic functionalized ordered mesoporous silica integrated dispersive solid phase extraction for determination of plant growth regulators in fresh panax ginseng
Talanta, 2020Co-Authors: Runsheng Si, Fengxia Qiao, Di Wu, Zhiqiang WangAbstract:Abstract The massive accumulation of plant growth regulators (PGRs) in Panax ginseng causes serious harm to human health. A new analytical method for the simultaneous determination of multiple PGRs in 19 types of fresh Panax ginseng is developed by a new designed wool cluster-inspired ionic liquid-functionalized ordered mesoporous silica-integrated dispersive solid-phase extraction coupled to high performance liquid chromatography (IL-WFOMS-I-DSPE-HPLC). The proposed method combines the advantages of the multiple adsorption mechanisms, high mass transfer rate and large adsorption capacity of the synthesized IL-WFOMS adsorbent with the safe, convenient operation of the new designed I-DSPE method. Under optimized conditions, the recoveries at three spike levels were in a range of 77.6–98.3% for 3-indole acetic Acid (IAA), 3-indole propionic Acid (IPA), 3-indole butyric Acid (IBA), and 1-Naphthaleneacetic Acid (NAA) with the relative standard deviations (RSD) ≤8.6%, n = 3. This method exhibits the advantages of safety, convenience, reliability, and has great potential for simultaneous determination of multiple trace PGRs in complex sample matrices.
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an ionic liquid functionalized graphene adsorbent with multiple adsorption mechanisms for pipette tip solid phase extraction of auxins in soybean sprouts
Food Chemistry, 2018Co-Authors: Hua Zhang, Fengxia Qiao, Yanan Yuan, Dandan Han, Hongyuan YanAbstract:Abstract A new ionic liquid functionalized graphene-pipette-tip solid-phase extraction method coupled with high-performance liquid chromatography was established for the simultaneous extraction and determination of three auxins in soybean sprouts. The graphene adsorbent, with multiple adsorption mechanisms, was first synthesized by functional modification of pentafluorobenzyl imidazolium bromide ionic liquid through thiol-ene click chemistry. The ionic liquid was applied to prevent the aggregation of graphene; it also imbued graphene with the ability for π-π interactions, ionic exchange, electrostatic interactions, as well as hydrogen bonding (which is stronger than the interaction between water and analytes), by augmenting the adsorption mechanisms between the adsorbent and analytes. Under optimized conditions, linearity was achieved in the ranges 0.03–5.00 µg/g for indole-3-acetic Acid and 1-Naphthaleneacetic Acid and 0.09–5.00 µg/g for 2,4-dichlorophenoxyacetic Acid, with a detection limit of 0.004–0.026 µg/g; this adsorbent has been successfully applied for the determination of auxins in soybean sprouts.
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hydrophilic molecularly imprinted melamine urea formaldehyde monolithic resin prepared in water for selective recognition of plant growth regulators
Analytica Chimica Acta, 2016Co-Authors: Jiankun Cao, Hongyuan Yan, Shigang Shen, Ligai Bai, Haiyan Liu, Fengxia QiaoAbstract:New hydrophilic molecularly imprinted melamine-urea-formaldehyde monolithic resin (MIMR) is synthesized using dopamine hydrochloride as a dummy template via in-situ polymerization directly within pipette tips and it presents special molecular recognition to plant growth regulators in aqueous matrices. Hydrophilic groups (such as hydroxyl groups, imino groups, and amino groups) can be introduced into MIMR by melamine– urea–formaldehyde resin, which make MIMR materials compatible with aqueous media and show their specific molecular recognition in aqueous sample solutions. Meanwhile, monolithic structures avoid the influence of uneven filling on the extraction efficiency. Various parameters affecting the selective recognition of MIMR have been optimized, such as molar ratio of melamine to urea, molar ratio of melamine and urea to formaldehyde, the amount of template and porogen. The prepared MIMR is applied as the sorbents of solid phase extraction (SPE) for sensitive and selective recognition of three plant growth regulators (p-chlorophenoxyacetic Acid, 1-Naphthaleneacetic Acid and 2.4-dichlorophenoxyacetic Acid) in bean sprouts. Considering its excellent hydrophilicity and specificity, MIMR–SPE is promising to be a potential pretreatment strategy in biological, environmental, and clinical fields.
Hongyuan Yan - One of the best experts on this subject based on the ideXlab platform.
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an ionic liquid functionalized graphene adsorbent with multiple adsorption mechanisms for pipette tip solid phase extraction of auxins in soybean sprouts
Food Chemistry, 2018Co-Authors: Hua Zhang, Fengxia Qiao, Yanan Yuan, Dandan Han, Hongyuan YanAbstract:Abstract A new ionic liquid functionalized graphene-pipette-tip solid-phase extraction method coupled with high-performance liquid chromatography was established for the simultaneous extraction and determination of three auxins in soybean sprouts. The graphene adsorbent, with multiple adsorption mechanisms, was first synthesized by functional modification of pentafluorobenzyl imidazolium bromide ionic liquid through thiol-ene click chemistry. The ionic liquid was applied to prevent the aggregation of graphene; it also imbued graphene with the ability for π-π interactions, ionic exchange, electrostatic interactions, as well as hydrogen bonding (which is stronger than the interaction between water and analytes), by augmenting the adsorption mechanisms between the adsorbent and analytes. Under optimized conditions, linearity was achieved in the ranges 0.03–5.00 µg/g for indole-3-acetic Acid and 1-Naphthaleneacetic Acid and 0.09–5.00 µg/g for 2,4-dichlorophenoxyacetic Acid, with a detection limit of 0.004–0.026 µg/g; this adsorbent has been successfully applied for the determination of auxins in soybean sprouts.
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hydrophilic molecularly imprinted melamine urea formaldehyde monolithic resin prepared in water for selective recognition of plant growth regulators
Analytica Chimica Acta, 2016Co-Authors: Jiankun Cao, Hongyuan Yan, Shigang Shen, Ligai Bai, Haiyan Liu, Fengxia QiaoAbstract:New hydrophilic molecularly imprinted melamine-urea-formaldehyde monolithic resin (MIMR) is synthesized using dopamine hydrochloride as a dummy template via in-situ polymerization directly within pipette tips and it presents special molecular recognition to plant growth regulators in aqueous matrices. Hydrophilic groups (such as hydroxyl groups, imino groups, and amino groups) can be introduced into MIMR by melamine– urea–formaldehyde resin, which make MIMR materials compatible with aqueous media and show their specific molecular recognition in aqueous sample solutions. Meanwhile, monolithic structures avoid the influence of uneven filling on the extraction efficiency. Various parameters affecting the selective recognition of MIMR have been optimized, such as molar ratio of melamine to urea, molar ratio of melamine and urea to formaldehyde, the amount of template and porogen. The prepared MIMR is applied as the sorbents of solid phase extraction (SPE) for sensitive and selective recognition of three plant growth regulators (p-chlorophenoxyacetic Acid, 1-Naphthaleneacetic Acid and 2.4-dichlorophenoxyacetic Acid) in bean sprouts. Considering its excellent hydrophilicity and specificity, MIMR–SPE is promising to be a potential pretreatment strategy in biological, environmental, and clinical fields.
Gengliang Yang - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of four plant hormones in bananas by molecularly imprinted solid phase extraction coupled with high performance liquid chromatography
Analyst, 2012Co-Authors: Fang Wang, Gengliang YangAbstract:A highly selective molecularly imprinted solid-phase extraction (MISPE) combined with liquid chromatography-ultraviolet detection was developed for the simultaneous isolation and determination of four plant hormones including indole-3-acetic Acid (IAA), indole-3-propionic Acid (IPA), indole-3-butyric Acid (IBA) and 1-Naphthaleneacetic Acid (NAA) in banana samples. The new molecularly imprinted microspheres (MIMs) prepared by aqueous suspension polymerization using 3-hydroxy-2-naphthoic Acid and 1-methylpiperazine as mimic templates performed with high selectivity and affinity for the four plant hormones, and applied as selective sorbents of solid-phase extraction could effectively eliminate the interferences of the banana matrix. Good linearity was obtained in a range of 0.04–4.00 μg g−1 and the recoveries of the four plant hormones at three spiked levels ranged from 78.5 to 107.7% with the relative standard deviations (RSD) of less than 4.6%. The developed MISPE-HPLC protocol obviously improved the selectivity and eliminated the effect of template leakage on quantitative analysis, and could be applied for the determination of plant hormones in complicated biological samples.
G. R. Rout - One of the best experts on this subject based on the ideXlab platform.
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micropropagation of clitoria ternatea linn fabaceae an important medicinal plant
In Vitro Cellular & Developmental Biology – Plant, 2005Co-Authors: G. R. RoutAbstract:An efficient protocol was established for in vitro shoot multiplication from nodal explants of Clitoria ternatea on semisolid Murashige and Skoog (MS) basal medium supplemented with 8.9μM 6-benzylaminopurine (BA). Inclusion of 1-Naphthaleneacetic Acid (NAA) in the culture medium along with BA promoted higher rates of shoot multiplication than BA alone. The rate of shoot multiplication was maximum (5.21) after 4 wk of culture on MS basal medium supplemented with 8.9μM BA and 1.34μM NAA. The elongated shoots rooted within 7–8d in half-strength MS basal salts supplemented with 1.34μM NAA and 2% (w/v) sucrose. About 85% of the rooted plantlets were acclimatized and transferred to the greenhouse.
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direct plant regeneration of curry leaf tree murraya koenigii koenig an aromatic plant
In Vitro Cellular & Developmental Biology – Plant, 2005Co-Authors: G. R. RoutAbstract:An efficient protocol for plant regeneration from stem segments of Murraya koenigii was developed by culturing on Murashige and Skoog (MS) medium supplemented with 2.5 mg l−1 benzyladenine (BA), 25 mgl−1 adenine sulfate, 0.25 mgl−1 indole-3-acetic Acid (IAA), and 3% sucrose. The frequency of shoot bud regeneration was higher on similar medium in subsequent subcultures. The regenerated shoots were rooted on half-strength basal MS medium supplemented with 0.25–0.5 mgl−1 IAA or 1-Naphthaleneacetic Acid (NAA) within 8–12 d of culture. The maximum percentage of rooting was obtained on MS medium supplemented with IAA and NAA, each at 0.25 mgl−1. During acclimatization, 95% of rooted plantlets survived were grown normally under greenhouse conditions.
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somatic embryogenesis and plant regeneration from callus culture of acacia catechu a multipurpose leguminous tree
Plant Cell Tissue and Organ Culture, 1995Co-Authors: G. R. Rout, S Samantaray, P DasAbstract:Plant regeneration via somatic embryogenesis was achieved from callus derived from immature cotyledons of Acacia catechu Willd. on Woody Plant Medium (WPM) supplemented with 13.9 μM kinetin and 2.7 μM 1-Naphthaleneacetic Acid. The addition of 0.9–3.5 mM L-proline to the medium influenced development of somatic embryos and also promoted secondary somatic embryogenesis. The light-green somatic embryos germinated on half-strength MS medium supplemented with 2% (w/v) sucrose. Somatic embryos germinated into plantlets that were acclimatized in the greenhouse and subsequently transferred to the field.
