The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform
Rilka Mladenova Taskova - One of the best experts on this subject based on the ideXlab platform.
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iridoid and phenylethanoid Glycosides in the new zealand sun hebes veronica plantaginaceae
Phytochemistry, 2012Co-Authors: Rilka Mladenova Taskova, Tetsuo Kokubun, P J Garnockjones, Soren Rosendal JensenAbstract:The sun hebes are a small clade of New Zealand Veronica formerly classified as Heliohebe. The water-soluble compounds of Veronica pentasepala, Veronica raoulii and Veronica hulkeana were studied and 30 compounds including 15 iridoid glucosides, 12 phenylethanoid Glycosides, the acetophenone glucoside pungenin, the mannitol ester hebitol II and mannitol were isolated. Of these, five were previously unknown in the literature: dihydroverminoside and 3,3′,4,4′-tetrahydroxy-α-truxillic acid 6-O-catalpyl diester, named heliosepaloside, as well as three phenylethanoid glycoside esters heliosides D, E and F, all derivatives of aragoside. The esters of cinnamic acid derivatives with iridoid and phenylethanoid Glycosides and an unusually high concentration of verminoside were found to be the most distinctive chemotaxonomic characters of the sun hebes. The chemical profiles of the species were compared and used to assess the phylogenetic relationships in the group.
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flavonoid profiles in the heliohebe group of new zealand veronica plantaginaceae
Biochemical Systematics and Ecology, 2008Co-Authors: Rilka Mladenova Taskova, Renee J Grayer, Tetsuo Kokubun, Ken G Ryan, P J GarnockjonesAbstract:Abstract The Heliohebe group of Veronica (sect. Hebe ) consists of five species occurring in the South Island of New Zealand. These species and a hybrid were analysed for their flavonoids. Five flavone Glycosides were isolated and identified by NMR spectroscopy and three additional Glycosides were detected by LC–UV–MS. Luteolin 7- O -, 3′- O - and 4′- O -glucosides and apigenin 7- O -glucoside were present in all six taxa investigated, 6-hydroxyluteolin Glycosides were found in five and a luteolin caffeoylglycoside in four taxa, while a hypolaetin 7- O -glycoside was detected only in Veronica pentasepala . The 3′- O - and 4′- O -glucosides of luteolin are also common in other species of Veronica sect. Hebe (restricted to the Southern Hemisphere), but are rare in Northern Hemisphere species of Veronica and thus act as good chemotaxonomic markers for the section. The relatively simple flavonoid profiles found in the Heliohebe group are plesiomorphic and consistent with the group's status as sister to the Hebe clade. Based on the detected flavonoids, two groups could be distinguished within the Heliohebe clade: (1) Veronica hulkeana , Veronica lavaudiana and Veronica raoulii , characterised by luteolin caffeoylglycoside, and (2) V. pentasepala and Veronica scrupea , where this compound is replaced by a 6-hydroxyluteolin dihexoside.
Francisco A Tomasbarberan - One of the best experts on this subject based on the ideXlab platform.
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liquid chromatography tandem mass spectrometry reveals the widespread occurrence of flavonoid Glycosides in honey and their potential as floral origin markers
Journal of Chromatography A, 2009Co-Authors: Pilar Truchado, Federico Ferreres, Francisco A TomasbarberanAbstract:HPLC-MS-MS analysis of unifloral honey extracts has shown the occurrence of flavonoid Glycosides in most of the analyzed samples. These compounds are not present in large amounts, but can reach up to 600 microg/100g honey in canola and rapeseed honeys. Rhamnosyl-hexosides (tentatively rutinosides and neohesperidosides) and dihexosides (hexosyl(1-->2)hexosides and hexosyl(1-->6)hexosides) of flavonols such as quercetin, kaempferol, isorhamnetin and 8-methoxykaempferol, are the main flavonoid Glycosides found in honey. However, flavonoid triGlycosides and monoGlycosides are also detected in some floral origins. Eucalyptus and orange blossom nectars were collected and analyzed showing that nectar flavonoid glucosides, as is the case of eucalyptus flavonoids, can be readily hydrolyzed by the bee saliva enzymes, while flavonoid rhamnosyl-glucosides, as is the case of citrus nectar flavonoids, are not hydrolyzed, and because of these reasons the flavonoid glycoside content of citrus honey is higher than that of eucalyptus honey that contains mainly aglycones. The flavonoid glycoside profiles detected in honeys suggest that this could be related to their floral origin and the results show that the HPLC-MSn ion trap analysis of flavonoid Glycosides in honey is a promising analytical method to help in the objective determination of the floral origin of unifloral honeys.
Soren Rosendal Jensen - One of the best experts on this subject based on the ideXlab platform.
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iridoid and phenylethanoid Glycosides in the new zealand sun hebes veronica plantaginaceae
Phytochemistry, 2012Co-Authors: Rilka Mladenova Taskova, Tetsuo Kokubun, P J Garnockjones, Soren Rosendal JensenAbstract:The sun hebes are a small clade of New Zealand Veronica formerly classified as Heliohebe. The water-soluble compounds of Veronica pentasepala, Veronica raoulii and Veronica hulkeana were studied and 30 compounds including 15 iridoid glucosides, 12 phenylethanoid Glycosides, the acetophenone glucoside pungenin, the mannitol ester hebitol II and mannitol were isolated. Of these, five were previously unknown in the literature: dihydroverminoside and 3,3′,4,4′-tetrahydroxy-α-truxillic acid 6-O-catalpyl diester, named heliosepaloside, as well as three phenylethanoid glycoside esters heliosides D, E and F, all derivatives of aragoside. The esters of cinnamic acid derivatives with iridoid and phenylethanoid Glycosides and an unusually high concentration of verminoside were found to be the most distinctive chemotaxonomic characters of the sun hebes. The chemical profiles of the species were compared and used to assess the phylogenetic relationships in the group.
P J Garnockjones - One of the best experts on this subject based on the ideXlab platform.
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iridoid and phenylethanoid Glycosides in the new zealand sun hebes veronica plantaginaceae
Phytochemistry, 2012Co-Authors: Rilka Mladenova Taskova, Tetsuo Kokubun, P J Garnockjones, Soren Rosendal JensenAbstract:The sun hebes are a small clade of New Zealand Veronica formerly classified as Heliohebe. The water-soluble compounds of Veronica pentasepala, Veronica raoulii and Veronica hulkeana were studied and 30 compounds including 15 iridoid glucosides, 12 phenylethanoid Glycosides, the acetophenone glucoside pungenin, the mannitol ester hebitol II and mannitol were isolated. Of these, five were previously unknown in the literature: dihydroverminoside and 3,3′,4,4′-tetrahydroxy-α-truxillic acid 6-O-catalpyl diester, named heliosepaloside, as well as three phenylethanoid glycoside esters heliosides D, E and F, all derivatives of aragoside. The esters of cinnamic acid derivatives with iridoid and phenylethanoid Glycosides and an unusually high concentration of verminoside were found to be the most distinctive chemotaxonomic characters of the sun hebes. The chemical profiles of the species were compared and used to assess the phylogenetic relationships in the group.
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flavonoid profiles in the heliohebe group of new zealand veronica plantaginaceae
Biochemical Systematics and Ecology, 2008Co-Authors: Rilka Mladenova Taskova, Renee J Grayer, Tetsuo Kokubun, Ken G Ryan, P J GarnockjonesAbstract:Abstract The Heliohebe group of Veronica (sect. Hebe ) consists of five species occurring in the South Island of New Zealand. These species and a hybrid were analysed for their flavonoids. Five flavone Glycosides were isolated and identified by NMR spectroscopy and three additional Glycosides were detected by LC–UV–MS. Luteolin 7- O -, 3′- O - and 4′- O -glucosides and apigenin 7- O -glucoside were present in all six taxa investigated, 6-hydroxyluteolin Glycosides were found in five and a luteolin caffeoylglycoside in four taxa, while a hypolaetin 7- O -glycoside was detected only in Veronica pentasepala . The 3′- O - and 4′- O -glucosides of luteolin are also common in other species of Veronica sect. Hebe (restricted to the Southern Hemisphere), but are rare in Northern Hemisphere species of Veronica and thus act as good chemotaxonomic markers for the section. The relatively simple flavonoid profiles found in the Heliohebe group are plesiomorphic and consistent with the group's status as sister to the Hebe clade. Based on the detected flavonoids, two groups could be distinguished within the Heliohebe clade: (1) Veronica hulkeana , Veronica lavaudiana and Veronica raoulii , characterised by luteolin caffeoylglycoside, and (2) V. pentasepala and Veronica scrupea , where this compound is replaced by a 6-hydroxyluteolin dihexoside.
Tetsuo Kokubun - One of the best experts on this subject based on the ideXlab platform.
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iridoid and phenylethanoid Glycosides in the new zealand sun hebes veronica plantaginaceae
Phytochemistry, 2012Co-Authors: Rilka Mladenova Taskova, Tetsuo Kokubun, P J Garnockjones, Soren Rosendal JensenAbstract:The sun hebes are a small clade of New Zealand Veronica formerly classified as Heliohebe. The water-soluble compounds of Veronica pentasepala, Veronica raoulii and Veronica hulkeana were studied and 30 compounds including 15 iridoid glucosides, 12 phenylethanoid Glycosides, the acetophenone glucoside pungenin, the mannitol ester hebitol II and mannitol were isolated. Of these, five were previously unknown in the literature: dihydroverminoside and 3,3′,4,4′-tetrahydroxy-α-truxillic acid 6-O-catalpyl diester, named heliosepaloside, as well as three phenylethanoid glycoside esters heliosides D, E and F, all derivatives of aragoside. The esters of cinnamic acid derivatives with iridoid and phenylethanoid Glycosides and an unusually high concentration of verminoside were found to be the most distinctive chemotaxonomic characters of the sun hebes. The chemical profiles of the species were compared and used to assess the phylogenetic relationships in the group.
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flavonoid profiles in the heliohebe group of new zealand veronica plantaginaceae
Biochemical Systematics and Ecology, 2008Co-Authors: Rilka Mladenova Taskova, Renee J Grayer, Tetsuo Kokubun, Ken G Ryan, P J GarnockjonesAbstract:Abstract The Heliohebe group of Veronica (sect. Hebe ) consists of five species occurring in the South Island of New Zealand. These species and a hybrid were analysed for their flavonoids. Five flavone Glycosides were isolated and identified by NMR spectroscopy and three additional Glycosides were detected by LC–UV–MS. Luteolin 7- O -, 3′- O - and 4′- O -glucosides and apigenin 7- O -glucoside were present in all six taxa investigated, 6-hydroxyluteolin Glycosides were found in five and a luteolin caffeoylglycoside in four taxa, while a hypolaetin 7- O -glycoside was detected only in Veronica pentasepala . The 3′- O - and 4′- O -glucosides of luteolin are also common in other species of Veronica sect. Hebe (restricted to the Southern Hemisphere), but are rare in Northern Hemisphere species of Veronica and thus act as good chemotaxonomic markers for the section. The relatively simple flavonoid profiles found in the Heliohebe group are plesiomorphic and consistent with the group's status as sister to the Hebe clade. Based on the detected flavonoids, two groups could be distinguished within the Heliohebe clade: (1) Veronica hulkeana , Veronica lavaudiana and Veronica raoulii , characterised by luteolin caffeoylglycoside, and (2) V. pentasepala and Veronica scrupea , where this compound is replaced by a 6-hydroxyluteolin dihexoside.
