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Ihab Ghabeish - One of the best experts on this subject based on the ideXlab platform.
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impact of flavonoids against woolly apple aphid eriosoma lanigerum hausmann and its sole parasitoid aphelinus mali hald
The Journal of Agricultural Science, 2012Co-Authors: Mazen A Ateyyat, Saeid Aburomman, Mohmmad Abudarwish, Ihab GhabeishAbstract:Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.
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impact of flavonoids against woolly apple aphid eriosoma lanigerum hausmann and its sole parasitoid aphelinus mali hald
The Journal of Agricultural Science, 2012Co-Authors: Mazen A Ateyyat, Saeid Aburomman, Mohmmad Abudarwish, Ihab GhabeishAbstract:Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.
Umesh R. Desai - One of the best experts on this subject based on the ideXlab platform.
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Capillary electrophoresis of highly sulfated Flavanoids and flavonoids.
Analytical biochemistry, 2005Co-Authors: Mandakini Dantuluri, Gunnar T. Gunnarsson, Muhammad Riaz, Huyen Nguyen, Umesh R. DesaiAbstract:Flavanoids and flavonoids are natural products present in our diet and known to possess multiple biological activities. Sulfated species of these natural products represent highly charged water-soluble organic molecules that possess unique biochemical properties. We describe here the first studies on capillary electrophoresis of these highly charged molecules. Fully sulfated Flavanoids and flavonoids can be electrophoresed and resolved under reverse polarity at pH 3.5 using 5-10 kV in less than 20 min. In contrast, at high pH under normal polarity these species can be electrophoresed only if a pressurized capillary is employed. (+/-)-Catechin sulfate, a racemic sulfated flavanoid, was resolved into its enantiomers using 15% beta-cyclodextrin, a chiral selector, but not with alpha- or gamma-cyclodextrins. Yet, the high charge density of these molecules challenges the resolving capability of capillary electrophoresis as diastereomers (-)-epicatechin sulfate and (+)-catechin sulfate do not resolve, even in the presence of cyclodextrins or chiral positively charged amino acids. Overall, capillary electrophoresis of highly sulfated Flavanoids and flavonoids is expected to be useful in rapid structure analysis of sulfated flavonoids, either synthetic or natural.
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capillary electrophoresis of highly sulfated Flavanoids and flavonoids
Analytical Biochemistry, 2005Co-Authors: Mandakini Dantuluri, Gunnar T. Gunnarsson, Muhammad Riaz, Huyen Nguyen, Umesh R. DesaiAbstract:Abstract Flavanoids and flavonoids are natural products present in our diet and known to possess multiple biological activities. Sulfated species of these natural products represent highly charged water-soluble organic molecules that possess unique biochemical properties. We describe here the first studies on capillary electrophoresis of these highly charged molecules. Fully sulfated Flavanoids and flavonoids can be electrophoresed and resolved under reverse polarity at pH 3.5 using 5–10 kV in less than 20 min. In contrast, at high pH under normal polarity these species can be electrophoresed only if a pressurized capillary is employed. (±)-Catechin sulfate, a racemic sulfated flavanoid, was resolved into its enantiomers using 15% β-cyclodextrin, a chiral selector, but not with α- or γ-cyclodextrins. Yet, the high charge density of these molecules challenges the resolving capability of capillary electrophoresis as diastereomers (−)-epicatechin sulfate and (+)-catechin sulfate do not resolve, even in the presence of cyclodextrins or chiral positively charged amino acids. Overall, capillary electrophoresis of highly sulfated Flavanoids and flavonoids is expected to be useful in rapid structure analysis of sulfated flavonoids, either synthetic or natural.
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Interaction of Designed Sulfated Flavanoids with Antithrombin: Lessons on the Design of Organic Activators
Journal of medicinal chemistry, 2002Co-Authors: Gunnar T. Gunnarsson, Umesh R. DesaiAbstract:Recently, we designed (-)-epicatechin sulfate (ECS), the first small nonsaccharide molecule, as an activator of antithrombin for the accelerated inhibition of factor Xa, a key proteinase of the coagulation cascade (Gunnarsson, G. T.; Desai, U. R. J. Med. Chem. 2002, 45, 1233-1243). Although sulfated flavanoid ECS was found to bind antithrombin with an affinity ( approximately 10.7 microM) comparable to the reference trisaccharide DEF ( approximately 4.5 microM), it accelerated the inhibition of factor Xa only 10-fold as compared to the approximately 300-fold observed with DEF. To determine whether this conformational activation of the inhibitor is dependent on the structure of the organic activator and to probe the basis for the deficiency in activation, we studied the interaction of similar sulfated Flavanoids with antithrombin. (+)-Catechin sulfate (CS), a chiral stereoisomer of ECS, bound plasma antithrombin with a 3-fold higher affinity (K(D) = 3.5 microM) and a 2-fold higher second-order rate constant for factor Xa inhibition (k(ACT) = 6750 M(-1) s(-1)). On the contrary, the K(D) and k(ACT) were found to be lower approximately 7.4- and approximately 2.4-fold, respectively, for its racemic counterpart, (+/-)-catechin sulfate. Dependence of the equilibrium dissociation constant on the ionic strength of the medium at pH 6.0 and 7.4 suggests that nonionic interactions contribute a major proportion ( approximately 55-73%) of the total binding energy, and only 1-2 ion pairs, in comparison to the expected approximately 4 ion pairs for the reference trisaccharide, are formed in the interaction. Competitive binding experiments indicate that activator CS does not compete with a saccharide ligand that binds antithrombin in the pentasaccharide binding site, while it competes with full-length low-affinity heparin. A molecular docking study suggests plausible binding of CS in the extended heparin binding site, which is adjacent to the binding domain for the reference trisaccharide DEF. In combination, the results demonstrate that although conformational activation of antithrombin with small sulfated Flavanoids is dependent on the structure of the activator, the designed activators do not bind in the pentasaccharide binding site in antithrombin resulting in weak activation. The mechanistic investigation highlights plausible directions to take in the rational design of specific high-affinity organic antithrombin activators.
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interaction of designed sulfated Flavanoids with antithrombin lessons on the design of organic activators
Journal of Medicinal Chemistry, 2002Co-Authors: Gunnar T. Gunnarsson, Umesh R. DesaiAbstract:Recently, we designed (−)-epicatechin sulfate (ECS), the first small nonsaccharide molecule, as an activator of antithrombin for the accelerated inhibition of factor Xa, a key proteinase of the coagulation cascade (Gunnarsson, G. T.; Desai, U. R. J. Med. Chem. 2002, 45, 1233−1243). Although sulfated flavanoid ECS was found to bind antithrombin with an affinity (∼10.7 μM) comparable to the reference trisaccharide DEF (∼4.5 μM), it accelerated the inhibition of factor Xa only 10-fold as compared to the ∼300-fold observed with DEF. To determine whether this conformational activation of the inhibitor is dependent on the structure of the organic activator and to probe the basis for the deficiency in activation, we studied the interaction of similar sulfated Flavanoids with antithrombin. (+)-Catechin sulfate (CS), a chiral stereoisomer of ECS, bound plasma antithrombin with a 3-fold higher affinity (KD = 3.5 μM) and a 2-fold higher second-order rate constant for factor Xa inhibition (kACT = 6750 M-1 s-1). On th...
Mazen A Ateyyat - One of the best experts on this subject based on the ideXlab platform.
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impact of flavonoids against woolly apple aphid eriosoma lanigerum hausmann and its sole parasitoid aphelinus mali hald
The Journal of Agricultural Science, 2012Co-Authors: Mazen A Ateyyat, Saeid Aburomman, Mohmmad Abudarwish, Ihab GhabeishAbstract:Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.
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impact of flavonoids against woolly apple aphid eriosoma lanigerum hausmann and its sole parasitoid aphelinus mali hald
The Journal of Agricultural Science, 2012Co-Authors: Mazen A Ateyyat, Saeid Aburomman, Mohmmad Abudarwish, Ihab GhabeishAbstract:Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.
Mohmmad Abudarwish - One of the best experts on this subject based on the ideXlab platform.
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impact of flavonoids against woolly apple aphid eriosoma lanigerum hausmann and its sole parasitoid aphelinus mali hald
The Journal of Agricultural Science, 2012Co-Authors: Mazen A Ateyyat, Saeid Aburomman, Mohmmad Abudarwish, Ihab GhabeishAbstract:Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.
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impact of flavonoids against woolly apple aphid eriosoma lanigerum hausmann and its sole parasitoid aphelinus mali hald
The Journal of Agricultural Science, 2012Co-Authors: Mazen A Ateyyat, Saeid Aburomman, Mohmmad Abudarwish, Ihab GhabeishAbstract:Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.
Saeid Aburomman - One of the best experts on this subject based on the ideXlab platform.
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impact of flavonoids against woolly apple aphid eriosoma lanigerum hausmann and its sole parasitoid aphelinus mali hald
The Journal of Agricultural Science, 2012Co-Authors: Mazen A Ateyyat, Saeid Aburomman, Mohmmad Abudarwish, Ihab GhabeishAbstract:Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.
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impact of flavonoids against woolly apple aphid eriosoma lanigerum hausmann and its sole parasitoid aphelinus mali hald
The Journal of Agricultural Science, 2012Co-Authors: Mazen A Ateyyat, Saeid Aburomman, Mohmmad Abudarwish, Ihab GhabeishAbstract:Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.