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Sonia Soares Costa - One of the best experts on this subject based on the ideXlab platform.
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immunomodulatory pretreatment with kalanchoe pinnata extract and its Quercitrin flavonoid effectively protects mice against fatal anaphylactic shock
International Immunopharmacology, 2008Co-Authors: Elaine A Cruz, Michelle Frazao Muzitano, Sonia Soares Costa, Silvia Amaral Goncalves Dasilva, Patricia M R E Silva, Bartira RossibergmannAbstract:Previously, we reported the immunosuppressive action of the aqueous extract of Kalanchoe pinnata (Kp) in mice. In the present study, we report on the protective effect of Kp in fatal anaphylactic shock, likewise a Th2-driven immunopathology, and the identification of its active component. Mice daily treated with oral Kp during hypersensitization with ovalbumin were all protected against death when challenged with the allergen, as compared with the 100% mortality in the untreated group. A single intraperitoneal dose 3 h prior to challenge was partially effective. Oral protection was accompanied by a reduced production of OVA-specific IgE antibodies, reduced eosinophilia, and impaired production of the IL-5, IL-10 and TNF-alpha cytokines. In vitro, Kp prevented antigen-induced mast cell degranulation and histamine release. Oral treatment with the Quercitrin flavonoid isolated from Kp prevented fatal anaphylaxis in 75% of the animals. These findings indicate that oral treatment with Kp effectively downmodulates pro-anaphylactic inducing immune responses. Protection achieved with Quercitrin, although not maximal, suggests that this flavonoid is a critical component of Kp extract against this extreme allergic reaction.
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the antileishmanial activity assessment of unusual flavonoids from kalanchoe pinnata
Phytochemistry, 2006Co-Authors: Michelle Frazao Muzitano, Carlos R Kaiser, Catherine Guette, Bartira Rossibergmann, Luzineide W Tinoco, Sonia Soares CostaAbstract:The importance of flavonoids for the antileishmanial activity of Kalanchoe pinnata was previously demonstrated by the isolation of Quercitrin, a potent antileishmanial flavonoid. In the present study, the aqueous leaf extract from the medicinal plant K. pinnata (Crassulaceae) afforded a kaempferol di-glycoside, named kapinnatoside, identified as kaempferol 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (1). In addition, two unusual flavonol and flavone glycosides already reported, quercetin 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (2) and 4',5-dihydroxy-3',8-dimethoxyflavone 7-O-beta-D-glucopyranoside (3), have been isolated. Their structures were determined via analyses of mono and bi-dimensional (1)H and (13)C NMR spectroscopic experiments and HR-MALDI mass spectra. Because of its restricted occurrence and its abundance in K. pinnata, flavonoid (2) may be a chemical marker for this plant species of high therapeutic potential. The three flavonoids were tested separately against Leishmania amazonenis amastigotes in comparison with Quercitrin, quercetin and afzelin. The quercetin aglycone - type structure, as well as a rhamnosyl unit linked at C-3, seem to be important for antileishmanial activity.
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Quercitrin an antileishmanial flavonoid glycoside from kalanchoe pinnata
Planta Medica, 2006Co-Authors: Michelle Frazao Muzitano, Elaine A Cruz, Ana Paula De Almeida, Silvia A G Da Silva, Carlos R Kaiser, Catherine Guette, Bartira Rossibergmann, Sonia Soares CostaAbstract:Quercitrin (quercetin 3- O-alpha- L-rhamnopyranoside), one of the constituents of the biologically active aqueous extract obtained from Kalanchoe pinnata, is demonstrated to be a potent antileishmanial compound (IC50 approximately 1 microg/mL) with a low toxicity profile. This is the first time that antileishmanial activity is demonstrated for a flavonoid glycoside.
Hoi-seon Lee - One of the best experts on this subject based on the ideXlab platform.
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cuminaldehyde aldose reductase and α glucosidase inhibitor derived from cuminum cyminum l seeds
Journal of Agricultural and Food Chemistry, 2005Co-Authors: Hoi-seon LeeAbstract:The inhibitory activity of Cuminum cyminum seed-isolated component was evaluated against lens aldose reductase and α-glucosidase isolated from Sprague−Dawley male rats and compared to that of 11 commercially available components derived from C. cyminum seed oil, as well as Quercitrin as an aldose reductase inhibitor and acarbose as an α-glucosidase inhibitor. The biologically active constituent of C. cyminum seed oil was characterized as cuminaldehyde by various spectral analyses. The IC50 value of cuminaldehyde is 0.00085 mg/mL against aldose reductase and 0.5 mg/mL against α-glucosidase, respectively. Cuminaldehyde was about 1.8 and 1.6 times less in inhibitory activity than acarbose and quercitin, respectively. Nonetheless, cuminaldehyde may be useful as a lead compound and a new agent for antidiabetic therapeutics. Keywords: Acarbose; aldose reductase; antidiabetic agent; antidiabetic complications; α-glucosidase; Cuminum cyminum; Quercitrin
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rat lens aldose reductase inhibitory activities of coptis japonica root derived isoquinoline alkaloids
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Hoi-seon LeeAbstract:The inhibitory activity of Coptis japonica root-derived materials was evaluated against lens aldose reductase isolated from male Sprague-Dawley rats and compared to that of three commercially available isoquinoline alkaloids (berberine sulfate, berberine iodide, and palmatine chloride), as well as Quercitrin as aldose reductase inhibitor. The biologically active constituents of C. japonica extract were characterized as the isoquinoline alkaloids, berberine chloride and palmatine iodide, by spectral analysis. The inhibitory effects varied with both chemical and concentration used. The IC(50) values of berberine chloride and palmatine iodide are 13.98 and 13.45 nM, respectively. Among three berberines and two palmatines, the inhibitory activity was much greater for the choridated and sulfated analogues than for those with iodide. Quercitrin was a much more potent inhibitor than berberines and palmatines. Nonetheless, berberines and palmatines may be useful as lead compounds and new agents for aldose reductase inhibition.
Michelle Frazao Muzitano - One of the best experts on this subject based on the ideXlab platform.
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immunomodulatory pretreatment with kalanchoe pinnata extract and its Quercitrin flavonoid effectively protects mice against fatal anaphylactic shock
International Immunopharmacology, 2008Co-Authors: Elaine A Cruz, Michelle Frazao Muzitano, Sonia Soares Costa, Silvia Amaral Goncalves Dasilva, Patricia M R E Silva, Bartira RossibergmannAbstract:Previously, we reported the immunosuppressive action of the aqueous extract of Kalanchoe pinnata (Kp) in mice. In the present study, we report on the protective effect of Kp in fatal anaphylactic shock, likewise a Th2-driven immunopathology, and the identification of its active component. Mice daily treated with oral Kp during hypersensitization with ovalbumin were all protected against death when challenged with the allergen, as compared with the 100% mortality in the untreated group. A single intraperitoneal dose 3 h prior to challenge was partially effective. Oral protection was accompanied by a reduced production of OVA-specific IgE antibodies, reduced eosinophilia, and impaired production of the IL-5, IL-10 and TNF-alpha cytokines. In vitro, Kp prevented antigen-induced mast cell degranulation and histamine release. Oral treatment with the Quercitrin flavonoid isolated from Kp prevented fatal anaphylaxis in 75% of the animals. These findings indicate that oral treatment with Kp effectively downmodulates pro-anaphylactic inducing immune responses. Protection achieved with Quercitrin, although not maximal, suggests that this flavonoid is a critical component of Kp extract against this extreme allergic reaction.
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the antileishmanial activity assessment of unusual flavonoids from kalanchoe pinnata
Phytochemistry, 2006Co-Authors: Michelle Frazao Muzitano, Carlos R Kaiser, Catherine Guette, Bartira Rossibergmann, Luzineide W Tinoco, Sonia Soares CostaAbstract:The importance of flavonoids for the antileishmanial activity of Kalanchoe pinnata was previously demonstrated by the isolation of Quercitrin, a potent antileishmanial flavonoid. In the present study, the aqueous leaf extract from the medicinal plant K. pinnata (Crassulaceae) afforded a kaempferol di-glycoside, named kapinnatoside, identified as kaempferol 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (1). In addition, two unusual flavonol and flavone glycosides already reported, quercetin 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (2) and 4',5-dihydroxy-3',8-dimethoxyflavone 7-O-beta-D-glucopyranoside (3), have been isolated. Their structures were determined via analyses of mono and bi-dimensional (1)H and (13)C NMR spectroscopic experiments and HR-MALDI mass spectra. Because of its restricted occurrence and its abundance in K. pinnata, flavonoid (2) may be a chemical marker for this plant species of high therapeutic potential. The three flavonoids were tested separately against Leishmania amazonenis amastigotes in comparison with Quercitrin, quercetin and afzelin. The quercetin aglycone - type structure, as well as a rhamnosyl unit linked at C-3, seem to be important for antileishmanial activity.
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Quercitrin an antileishmanial flavonoid glycoside from kalanchoe pinnata
Planta Medica, 2006Co-Authors: Michelle Frazao Muzitano, Elaine A Cruz, Ana Paula De Almeida, Silvia A G Da Silva, Carlos R Kaiser, Catherine Guette, Bartira Rossibergmann, Sonia Soares CostaAbstract:Quercitrin (quercetin 3- O-alpha- L-rhamnopyranoside), one of the constituents of the biologically active aqueous extract obtained from Kalanchoe pinnata, is demonstrated to be a potent antileishmanial compound (IC50 approximately 1 microg/mL) with a low toxicity profile. This is the first time that antileishmanial activity is demonstrated for a flavonoid glycoside.
Asad U Khan - One of the best experts on this subject based on the ideXlab platform.
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Inhibition of Major Virulence Pathways of Streptococcus mutans by Quercitrin and Deoxynojirimycin: A Synergistic Approach of Infection Control
2016Co-Authors: Sadaf Hasan, Kunal Singh, Mohd Danisuddin, Praveen Kumar Verma, Asad U KhanAbstract:Objectives: To evaluate the synergistic effect of Quercitrin and Deoxynojirimycin (DNJ) together with their individual inhibitory effect against virulence pathways of Streptococcus mutans. Methodology: MICs of both the compounds were determined by the microdilution method, followed by their in vitrosynergy using checkerboard and time kill assay. The nature of interaction was classified as synergistic on the basis of fractional inhibitory concentration index (FICI) value of #0.5. Furthermore, the activity of Quercitrin and DNJ was evaluated individually and in combination against various cariogenic properties of S. mutans UA159 such as acidogenesis, aciduracity, glucan production, hydrophobicity, biofilm and adherence. Moreover, expression of virulent genes in S. mutans was analysed by quantitative RT- PCR (qRT-PCR) and inhibition of F1F0-ATPase, lactate dehydrogenase and enolase was also evaluated. Finally, scanning electron microscopy (SEM) was used to investigate structural obliteration of biofilm. Results: The in vitro synergism between Quercitrin and DNJ was observed, with a FICI of 0.313. Their MIC values were found to be 64 mg/ml and 16 mg/ml respectively. The synergistic combination consistently showed best activity against all the virulence factors as compared to Quercitrin and DNJ individually. A reduction in glucan synthesis and biofilm formation was observed at different phases of growth. The qRT-PCR revealed significant downregulation of various virulent genes. Electron micrographs depicted the obliteration of biofilm as compared to control and the activity of cariogenic enzymes was als
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inhibition of major virulence pathways of streptococcus mutans by Quercitrin and deoxynojirimycin a synergistic approach of infection control
PLOS ONE, 2014Co-Authors: Sadaf Hasan, Kunal Singh, Mohd Danisuddin, Praveen Kumar Verma, Asad U KhanAbstract:Objectives To evaluate the synergistic effect of Quercitrin and Deoxynojirimycin (DNJ) together with their individual inhibitory effect against virulence pathways of Streptococcus mutans. Methodology MICs of both the compounds were determined by the microdilution method, followed by their in vitrosynergy using checkerboard and time kill assay. The nature of interaction was classified as synergistic on the basis of fractional inhibitory concentration index (FICI) value of ≤0.5. Furthermore, the activity of Quercitrin and DNJ was evaluated individually and in combination against various cariogenic properties of S. mutans UA159 such as acidogenesis, aciduracity, glucan production, hydrophobicity, biofilm and adherence. Moreover, expression of virulent genes in S. mutans was analysed by quantitative RT- PCR (qRT-PCR) and inhibition of F1F0-ATPase, lactate dehydrogenase and enolase was also evaluated. Finally, scanning electron microscopy (SEM) was used to investigate structural obliteration of biofilm. Results The in vitro synergism between Quercitrin and DNJ was observed, with a FICI of 0.313. Their MIC values were found to be 64 μg/ml and 16 μg/ml respectively. The synergistic combination consistently showed best activity against all the virulence factors as compared to Quercitrin and DNJ individually. A reduction in glucan synthesis and biofilm formation was observed at different phases of growth. The qRT-PCR revealed significant downregulation of various virulent genes. Electron micrographs depicted the obliteration of biofilm as compared to control and the activity of cariogenic enzymes was also inhibited. Conclusions The whole study reflects a prospective role of Quercitrin and DNJ in combination as a potent anticariogenic agent against S. mutans.
Bartira Rossibergmann - One of the best experts on this subject based on the ideXlab platform.
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immunomodulatory pretreatment with kalanchoe pinnata extract and its Quercitrin flavonoid effectively protects mice against fatal anaphylactic shock
International Immunopharmacology, 2008Co-Authors: Elaine A Cruz, Michelle Frazao Muzitano, Sonia Soares Costa, Silvia Amaral Goncalves Dasilva, Patricia M R E Silva, Bartira RossibergmannAbstract:Previously, we reported the immunosuppressive action of the aqueous extract of Kalanchoe pinnata (Kp) in mice. In the present study, we report on the protective effect of Kp in fatal anaphylactic shock, likewise a Th2-driven immunopathology, and the identification of its active component. Mice daily treated with oral Kp during hypersensitization with ovalbumin were all protected against death when challenged with the allergen, as compared with the 100% mortality in the untreated group. A single intraperitoneal dose 3 h prior to challenge was partially effective. Oral protection was accompanied by a reduced production of OVA-specific IgE antibodies, reduced eosinophilia, and impaired production of the IL-5, IL-10 and TNF-alpha cytokines. In vitro, Kp prevented antigen-induced mast cell degranulation and histamine release. Oral treatment with the Quercitrin flavonoid isolated from Kp prevented fatal anaphylaxis in 75% of the animals. These findings indicate that oral treatment with Kp effectively downmodulates pro-anaphylactic inducing immune responses. Protection achieved with Quercitrin, although not maximal, suggests that this flavonoid is a critical component of Kp extract against this extreme allergic reaction.
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the antileishmanial activity assessment of unusual flavonoids from kalanchoe pinnata
Phytochemistry, 2006Co-Authors: Michelle Frazao Muzitano, Carlos R Kaiser, Catherine Guette, Bartira Rossibergmann, Luzineide W Tinoco, Sonia Soares CostaAbstract:The importance of flavonoids for the antileishmanial activity of Kalanchoe pinnata was previously demonstrated by the isolation of Quercitrin, a potent antileishmanial flavonoid. In the present study, the aqueous leaf extract from the medicinal plant K. pinnata (Crassulaceae) afforded a kaempferol di-glycoside, named kapinnatoside, identified as kaempferol 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (1). In addition, two unusual flavonol and flavone glycosides already reported, quercetin 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (2) and 4',5-dihydroxy-3',8-dimethoxyflavone 7-O-beta-D-glucopyranoside (3), have been isolated. Their structures were determined via analyses of mono and bi-dimensional (1)H and (13)C NMR spectroscopic experiments and HR-MALDI mass spectra. Because of its restricted occurrence and its abundance in K. pinnata, flavonoid (2) may be a chemical marker for this plant species of high therapeutic potential. The three flavonoids were tested separately against Leishmania amazonenis amastigotes in comparison with Quercitrin, quercetin and afzelin. The quercetin aglycone - type structure, as well as a rhamnosyl unit linked at C-3, seem to be important for antileishmanial activity.
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Quercitrin an antileishmanial flavonoid glycoside from kalanchoe pinnata
Planta Medica, 2006Co-Authors: Michelle Frazao Muzitano, Elaine A Cruz, Ana Paula De Almeida, Silvia A G Da Silva, Carlos R Kaiser, Catherine Guette, Bartira Rossibergmann, Sonia Soares CostaAbstract:Quercitrin (quercetin 3- O-alpha- L-rhamnopyranoside), one of the constituents of the biologically active aqueous extract obtained from Kalanchoe pinnata, is demonstrated to be a potent antileishmanial compound (IC50 approximately 1 microg/mL) with a low toxicity profile. This is the first time that antileishmanial activity is demonstrated for a flavonoid glycoside.
