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Junichi Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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celogenamide a a new cyclic peptide from the seeds of Celosia argentea
Journal of Natural Products, 2004Co-Authors: Hiroshi Morita, Hayato Suzuki, Junichi KobayashiAbstract:A new cyclic nonapeptide, celogenamide A (1), has been isolated from the seeds of Celosia argentea, and the structure including absolute stereochemistry was determined by using extensive 2D NMR and MS-MS methods and chemical means.
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celogentin k a new cyclic peptide from the seeds of Celosia argentea and x ray structure of moroidin
Tetrahedron, 2004Co-Authors: Hayato Suzuki, Hiroshi Morita, Motoo Shiro, Junichi KobayashiAbstract:A new cyclic peptide with a 3-hydroxyoxindole ring, celogentin K (1), has been isolated from the seeds of Celosia argentea and the structure including its absolute stereochemistry was assigned by using extensive NMR, MS/MS, and CD spectra. The stereostructure of a known related bicyclic peptide, moroidin (2), was confirmed by a single crystal X-ray diffraction analysis.
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new antimitotic bicyclic peptides celogentins d h and j from the seeds of Celosia argentea
Tetrahedron, 2003Co-Authors: Hayato Suzuki, Hiroshi Morita, Shigeo Iwasaki, Junichi KobayashiAbstract:Abstract Six new bicyclic peptides, celogentins D–H ( 1–5 ) and J ( 6 ) have been isolated from the seeds of Celosia argentea, and the structures including its absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins E–H ( 2–5 ) and J ( 6 ) showed potent inhibition of tubulin polymerization, while the inhibitory activity of celogentin D ( 1 ) was modest. Structure–activity relationship study indicates that ring size of the bicyclic ring system including unusual βs-Leu, Trp, and His residues would be important for their biological activity.
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New antimitotic bicyclic peptides, celogentins D–H, and J, from the seeds of Celosia argentea
Tetrahedron, 2003Co-Authors: Hayato Suzuki, Hiroshi Morita, Shigeo Iwasaki, Junichi KobayashiAbstract:Abstract Six new bicyclic peptides, celogentins D–H ( 1–5 ) and J ( 6 ) have been isolated from the seeds of Celosia argentea, and the structures including its absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins E–H ( 2–5 ) and J ( 6 ) showed potent inhibition of tubulin polymerization, while the inhibitory activity of celogentin D ( 1 ) was modest. Structure–activity relationship study indicates that ring size of the bicyclic ring system including unusual βs-Leu, Trp, and His residues would be important for their biological activity.
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celogentins a c new antimitotic bicyclic peptides from the seeds of Celosia argentea
Journal of Organic Chemistry, 2001Co-Authors: Junichi Kobayashi, Hayato Suzuki, Kazutaka Shimbo, Koichi Takeya, Hiroshi MoritaAbstract:Three new bicyclic peptides, celogentins A (1), B (2), and C (3), have been isolated together with a known-related peptide, moroidin (4), from the seeds of Celosia argentea, and their structures including absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins A (1), B (2), and C (3) inhibited the polymerization of tubulin, and celogentin C (3) was four times more potent than moroidin (4) in the inhibitory activity. Structure−activity relationship study using moroidin derivatives 5−7 and analogue 8 as well as celogentins A−C (1−3) and moroidin (4) indicates that the bicyclic ring system including unusual non-peptide connections among βs-Leu, Trp, and His residues characteristic of celogentins and moroidin, with ring size and conformations suitable for interaction with tubulin would be important for their biological activity.
Hiroshi Morita - One of the best experts on this subject based on the ideXlab platform.
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celogenamide a a new cyclic peptide from the seeds of Celosia argentea
Journal of Natural Products, 2004Co-Authors: Hiroshi Morita, Hayato Suzuki, Junichi KobayashiAbstract:A new cyclic nonapeptide, celogenamide A (1), has been isolated from the seeds of Celosia argentea, and the structure including absolute stereochemistry was determined by using extensive 2D NMR and MS-MS methods and chemical means.
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celogentin k a new cyclic peptide from the seeds of Celosia argentea and x ray structure of moroidin
Tetrahedron, 2004Co-Authors: Hayato Suzuki, Hiroshi Morita, Motoo Shiro, Junichi KobayashiAbstract:A new cyclic peptide with a 3-hydroxyoxindole ring, celogentin K (1), has been isolated from the seeds of Celosia argentea and the structure including its absolute stereochemistry was assigned by using extensive NMR, MS/MS, and CD spectra. The stereostructure of a known related bicyclic peptide, moroidin (2), was confirmed by a single crystal X-ray diffraction analysis.
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new antimitotic bicyclic peptides celogentins d h and j from the seeds of Celosia argentea
Tetrahedron, 2003Co-Authors: Hayato Suzuki, Hiroshi Morita, Shigeo Iwasaki, Junichi KobayashiAbstract:Abstract Six new bicyclic peptides, celogentins D–H ( 1–5 ) and J ( 6 ) have been isolated from the seeds of Celosia argentea, and the structures including its absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins E–H ( 2–5 ) and J ( 6 ) showed potent inhibition of tubulin polymerization, while the inhibitory activity of celogentin D ( 1 ) was modest. Structure–activity relationship study indicates that ring size of the bicyclic ring system including unusual βs-Leu, Trp, and His residues would be important for their biological activity.
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New antimitotic bicyclic peptides, celogentins D–H, and J, from the seeds of Celosia argentea
Tetrahedron, 2003Co-Authors: Hayato Suzuki, Hiroshi Morita, Shigeo Iwasaki, Junichi KobayashiAbstract:Abstract Six new bicyclic peptides, celogentins D–H ( 1–5 ) and J ( 6 ) have been isolated from the seeds of Celosia argentea, and the structures including its absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins E–H ( 2–5 ) and J ( 6 ) showed potent inhibition of tubulin polymerization, while the inhibitory activity of celogentin D ( 1 ) was modest. Structure–activity relationship study indicates that ring size of the bicyclic ring system including unusual βs-Leu, Trp, and His residues would be important for their biological activity.
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celogentins a c new antimitotic bicyclic peptides from the seeds of Celosia argentea
Journal of Organic Chemistry, 2001Co-Authors: Junichi Kobayashi, Hayato Suzuki, Kazutaka Shimbo, Koichi Takeya, Hiroshi MoritaAbstract:Three new bicyclic peptides, celogentins A (1), B (2), and C (3), have been isolated together with a known-related peptide, moroidin (4), from the seeds of Celosia argentea, and their structures including absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins A (1), B (2), and C (3) inhibited the polymerization of tubulin, and celogentin C (3) was four times more potent than moroidin (4) in the inhibitory activity. Structure−activity relationship study using moroidin derivatives 5−7 and analogue 8 as well as celogentins A−C (1−3) and moroidin (4) indicates that the bicyclic ring system including unusual non-peptide connections among βs-Leu, Trp, and His residues characteristic of celogentins and moroidin, with ring size and conformations suitable for interaction with tubulin would be important for their biological activity.
Hayato Suzuki - One of the best experts on this subject based on the ideXlab platform.
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celogenamide a a new cyclic peptide from the seeds of Celosia argentea
Journal of Natural Products, 2004Co-Authors: Hiroshi Morita, Hayato Suzuki, Junichi KobayashiAbstract:A new cyclic nonapeptide, celogenamide A (1), has been isolated from the seeds of Celosia argentea, and the structure including absolute stereochemistry was determined by using extensive 2D NMR and MS-MS methods and chemical means.
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celogentin k a new cyclic peptide from the seeds of Celosia argentea and x ray structure of moroidin
Tetrahedron, 2004Co-Authors: Hayato Suzuki, Hiroshi Morita, Motoo Shiro, Junichi KobayashiAbstract:A new cyclic peptide with a 3-hydroxyoxindole ring, celogentin K (1), has been isolated from the seeds of Celosia argentea and the structure including its absolute stereochemistry was assigned by using extensive NMR, MS/MS, and CD spectra. The stereostructure of a known related bicyclic peptide, moroidin (2), was confirmed by a single crystal X-ray diffraction analysis.
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new antimitotic bicyclic peptides celogentins d h and j from the seeds of Celosia argentea
Tetrahedron, 2003Co-Authors: Hayato Suzuki, Hiroshi Morita, Shigeo Iwasaki, Junichi KobayashiAbstract:Abstract Six new bicyclic peptides, celogentins D–H ( 1–5 ) and J ( 6 ) have been isolated from the seeds of Celosia argentea, and the structures including its absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins E–H ( 2–5 ) and J ( 6 ) showed potent inhibition of tubulin polymerization, while the inhibitory activity of celogentin D ( 1 ) was modest. Structure–activity relationship study indicates that ring size of the bicyclic ring system including unusual βs-Leu, Trp, and His residues would be important for their biological activity.
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New antimitotic bicyclic peptides, celogentins D–H, and J, from the seeds of Celosia argentea
Tetrahedron, 2003Co-Authors: Hayato Suzuki, Hiroshi Morita, Shigeo Iwasaki, Junichi KobayashiAbstract:Abstract Six new bicyclic peptides, celogentins D–H ( 1–5 ) and J ( 6 ) have been isolated from the seeds of Celosia argentea, and the structures including its absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins E–H ( 2–5 ) and J ( 6 ) showed potent inhibition of tubulin polymerization, while the inhibitory activity of celogentin D ( 1 ) was modest. Structure–activity relationship study indicates that ring size of the bicyclic ring system including unusual βs-Leu, Trp, and His residues would be important for their biological activity.
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celogentins a c new antimitotic bicyclic peptides from the seeds of Celosia argentea
Journal of Organic Chemistry, 2001Co-Authors: Junichi Kobayashi, Hayato Suzuki, Kazutaka Shimbo, Koichi Takeya, Hiroshi MoritaAbstract:Three new bicyclic peptides, celogentins A (1), B (2), and C (3), have been isolated together with a known-related peptide, moroidin (4), from the seeds of Celosia argentea, and their structures including absolute stereochemistry were determined by using extensive NMR methods and chemical means. Celogentins A (1), B (2), and C (3) inhibited the polymerization of tubulin, and celogentin C (3) was four times more potent than moroidin (4) in the inhibitory activity. Structure−activity relationship study using moroidin derivatives 5−7 and analogue 8 as well as celogentins A−C (1−3) and moroidin (4) indicates that the bicyclic ring system including unusual non-peptide connections among βs-Leu, Trp, and His residues characteristic of celogentins and moroidin, with ring size and conformations suitable for interaction with tubulin would be important for their biological activity.
O. L. Erukainure - One of the best experts on this subject based on the ideXlab platform.
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Methanolic extract of Celosia argentea var. crista leaves modulates glucose homeostasis and abates oxidative hepatic injury in diabetic rats.
Comparative Haematology International, 2018Co-Authors: R. U. Hamzah, A. R. Lawal, F. M. Madaki, O. L. ErukainureAbstract:: Celosia argentea commonly known as cockscomb plant is widely used in folkloric medicine in the treatment and management of diabetes mellitus. The effect of methanolic extract of Celosia argentea var. cristata L. (CAVCL) leaves on blood glucose level, superoxide dismutase (SOD), catalase (CAT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) activities, and malondialdehyde (MDA) level were evaluated in diabetic rats. Five groups of male albino rats consisting of 5 animals each were used for the present study. They were grouped as normal control, diabetic control, diabetic administered with 250 and 750 mg/kg b.w C. argentea, and 5 mg/kg b.w glibenclamide. Diabetes was induced with alloxan monohydrate intraperitoneally at 120 mg/kg b.w. The control and diabetic groups were given distilled water and rat chow for 21 days. Blood glucose level of each group was estimated every week, and at the end of the experiment, SOD, CAT, MDA and serum ALP, and AST and ALT activities were assayed in the liver and serum respectively of the experimental animals. The results showed a significant increase (p
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methanolic extract of Celosia argentea var crista leaves modulates glucose homeostasis and abates oxidative hepatic injury in diabetic rats
Comparative Haematology International, 2018Co-Authors: R. U. Hamzah, A. R. Lawal, F. M. Madaki, O. L. ErukainureAbstract:: Celosia argentea commonly known as cockscomb plant is widely used in folkloric medicine in the treatment and management of diabetes mellitus. The effect of methanolic extract of Celosia argentea var. cristata L. (CAVCL) leaves on blood glucose level, superoxide dismutase (SOD), catalase (CAT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) activities, and malondialdehyde (MDA) level were evaluated in diabetic rats. Five groups of male albino rats consisting of 5 animals each were used for the present study. They were grouped as normal control, diabetic control, diabetic administered with 250 and 750 mg/kg b.w C. argentea, and 5 mg/kg b.w glibenclamide. Diabetes was induced with alloxan monohydrate intraperitoneally at 120 mg/kg b.w. The control and diabetic groups were given distilled water and rat chow for 21 days. Blood glucose level of each group was estimated every week, and at the end of the experiment, SOD, CAT, MDA and serum ALP, and AST and ALT activities were assayed in the liver and serum respectively of the experimental animals. The results showed a significant increase (p < 0.05) in serum AST, ALP, and ALT activities and reduction in SOD and CAT activities compared with normal control groups. The extract at both doses significantly lowered the high levels of the serum enzymes and increased the level of CAT and SOD. These results indicate an anti-hyperglycemia and antioxidative protective effect of C. argentea leaves.
Harold Corke - One of the best experts on this subject based on the ideXlab platform.
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Betalains of Celosia argentea
Phytochemistry, 2001Co-Authors: Willibald Schliemann, Thomas Degenkolb, Jürgen Schmidt, Harold CorkeAbstract:The betalains of yellow, orange and red inflorescences of common cockscomb (Celosia argentea var. cristata) were compared and proved to be qualitatively identical to those of feathered amaranth (Celosia argentea var. plumosa). In addition to the known compounds amaranthin and betalamic acid, the structures of three yellow pigments were elucidated to be immonium conjugates of betalamic acid with dopamine, 3-methoxytyramine and (S)-tryptophan by various spectroscopic techniques and comparison to synthesized reference compounds; the latter two are new to plants. Among the betacyanins occurring in yellow inflorescences in trace amounts, the presence of 2-descarboxy-betanidin, a dopamine-derived betacyanin, has been ascertained. The detection of high dopamine concentration may be of toxicological relevance in use of yellow inflorescences as a vegetable and in traditional Chinese medicine, common uses for the red inflorescences of common cockscomb.
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chemical stability and colorant properties of betaxanthin pigments from Celosia argentea
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Willibald Schliemann, Harold CorkeAbstract:The chemical stability and colorant properties of three betaxanthins recently identified from Celosia argentea varieties were evaluated. Lyophilized betaxanthin powders from yellow inflorescences of Celosia exhibited bright yellow color and high color purity with strong hygroscopicity. The aqueous solutions containing these betaxanthins were bright yellow in the pH range 2.2−7.0, and they were most stable at pH 5.5. The betaxanthins in a model system (buffer) were susceptible to heat, and found to be as unstable as red betacyanins (betanin and amaranthine) at high temperatures (>40 °C), but more stable at 40 °C with the exclusion of light and air. The three betaxanthins had slightly higher pigment retention than amaranthine/isoamaranthine in crude extracts at 22 °C, as verified by HPLC analysis. Lyophilized betaxanthins had much better storage stability (mean 95.0% pigment retention) than corresponding aqueous solutions (14.8%) at 22 °C after 20 weeks. Refrigeration (4 °C) significantly increased pigment ...