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Cuneyt Cirak - One of the best experts on this subject based on the ideXlab platform.
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Secondary metabolites of Hypericum orientale L. growing in Turkey: variation among populations and plant parts
Acta Physiologiae Plantarum, 2012Co-Authors: Cuneyt Cirak, Necdet Camas, Jolita Radusiene, Zydrunas Stanius, Omer Caliskan, Mehmet Serhat OdabasAbstract:The present study was conducted to determine the variation in the content of several plant chemicals, namely hyperforin, hypericin, Pseudohypericin, chlorogenic acid, rutin, hyperoside, isoquercetine, kaempferol, quercitrine and quercetine among ten Hypericum orientale L. populations from Northern Turkey. The aerial parts representing a total of 30 individuals were collected at full flowering and dissected into floral, leaf and stem tissues. After dried at room temperature, the plant materials were assayed for chemical contents by HPLC. The populations varied significantly in chemical contents. Among different plant parts, the flowers were found to be the principle organ for hyperforin, hypericin, Pseudohypericin and rutin accumulations while the rest of the chemicals were accumulated mainly in leaves in all growing localities. The chemical variation among the populations and plant parts is discussed as being possibly the result of different genetic, environmental and morphological factors.
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Secondary Metabolites of Hypericum leptophyllum Hochst., an Endemic Turkish Species
Hindawi Limited, 2012Co-Authors: Necdet Camas, Jolita Radusiene, Zydrunas Stanius, Omer Caliskan, Cuneyt CirakAbstract:In the present study, the presence of the phloroglucinol derivative hyperforin, the naphthodianthrones hypericin and Pseudohypericin, the phenylpropane chlorogenic acid and the flavonoids rutin, hyperoside, kaempferol, isoquercetine, quercitrine, and quercetine was investigated in Hypericum leptophyllum Hochst., an endemic Turkish species for the first time. The aerial parts representing a total of 30 individuals were collected at full flowering and dissected into floral, leaf, and stem tissues. After being dried at room temperature, the plant materials were assayed for secondary metabolite concentrations by HPLC. Aerial plant parts accumulated chlorogenic acid, hyperoside, isoquercetine, quercitrine, and quercetine, but they did not accumulate hyperforin, hypericin, Pseudohypericin, rutin, and kaempferol. Accumulation levels of the detected compounds varied with plant tissues. Such kind of data could be useful for elucidation of the chemotaxonomical significance of the corresponding compounds and phytochemical evaluation of this endemic species
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Secondary metabolites of Hypericum confertum and their possible chemotaxonomic significance.
Natural product communications, 2010Co-Authors: Cuneyt Cirak, Jolita Radusiene, Valdimaras Janulis, Liudas IvanauskasAbstract:The phloroglucinol derivative hyperforin, the naphthodianthrones hypericin and Pseudohypericin, the phenylpropane chlorogenic acid, and the flavonoids rutin, hyperoside, apigenin-7-O-glucoside, kaempferol, quercitrin, quercetin and amentoflavone were investigated in Hypericum confertum growing wild in Turkey. After drying at room temperature, the plant materials were assayed for secondary metabolite concentrations by HPLC. All the listed compounds were detected at various levels. This is the first report on the chemistry of H. confertum.
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The quantitative effects of temperature and light intensity on hyperforin and hypericins accumulation in Hypericum perforatum L
Journal of Medicinal Plants Research, 2009Co-Authors: Mehmet Serhat Odabas, Necdet Camas, J. Raduğienë, Valdimaras Janulis, Liudas Ivanauskas, Cuneyt CirakAbstract:The quantitative effects of temperature and light intensity on accumulations of hyperforin, hypericin and Pseudohypericin were examined in greenhouse-grownHypericum perforatum L. plants. Polyethylene cover of 50% transparency was used for shading. Temperature values and light intensities were measured daily in both shaded and un-shaded parts during experiment. Plants were harvested weekly and assayed for the chemical concentrations by HPLC after being dried at room temperature. Multi regression analyses were performed to describe the quantitative effects of temperature and light intensity on accumulation of phytochemicals. According to the results, increases in temperatures from 24 - 32°C and light intensities from 803.4 - 1618.6 µmolm-2s-1 resulted in a continuous increase in hyperforin, hypericin and Pseudohypericin contents. The relationships between temperatures & light intensity and accumulation of phytochemicals were formulized as PC = [a + (b1 x t) + (b2 x l) + (b3 x l²) + (b4 x (t x l))] where PC – phytochemicals, t–temperature (°C), l–light intensity (µmolm-2s-1), and a, b1, b2, b3 and b4–coefficients of the produced equations. R2? Values were 0.80 for hyperforin, 0.93 for hypericin and 0.96 for Pseudohypericin. All R2 values and standard errors of the equations were found to be significant at the p < 0.001 level. Key words: Hypericum perforatum, hyperforin, hypericin, Pseudohypericin, light, temperature, modeling.
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Variation of hypericins in Hypericum triquetrifolium Turra growing in different locations of Turkey during plant growth.
Natural product research, 2008Co-Authors: Ali Kemal Ayan, Cuneyt CirakAbstract:The principle medicinal secondary metabolites present in Hypericum species are thought to be naphthodianthrones hypericin and Pseudohypericin. The present study was conducted to determine ontogenetic and morphogenetic variations of hypericin and Pseudohypericin contents in Hypericum triquetrifolium growing in two sites located in Northern Turkey. Plants were harvested at vegetative, flowering and fructification stages. Plants were dissected into stem, leaf and reproductive tissues at the time of harvest, dried separately and assayed for hypericin and Pseudohypericin contents by high-performance liquid chromatography. The hypericin and Pseudohypericin concentrations in the leaves and reproductive parts were highest at flowering and fructification, whereas the stem contents of these compounds decreased with advancing plant growth in both sites. The leaves contained higher concentrations of both naphthodianthrones than the stems or reproductive parts of H. triquetrifolium.
Th. Kartnig - One of the best experts on this subject based on the ideXlab platform.
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determination of hypericin and Pseudohypericin by thin layer chromatography densitometry
Journal of Chromatography A, 1992Co-Authors: Th. Kartnig, Go I BelAbstract:Abstract The accuracy and reproducibility of the determination of hypericin and Pseudohypericin by measuring the emitted fluorescence in situ on thin-layer chromatography plates can be improved significantly by using appropriate dipping reagents. The effects of pyridine, polyethylene glycol 4000, paraffins, silicone oil and Triton X-100 in various solvents and combinations on the intensity and stability of emitted fluorescence are described. Using the test conditions established by this investigation, hypericin can be quantified exactly within the range 5–50 ng and Pseudohypericin within the range 20–200 ng. The relative standard deviation for the quantification under the given conditions is less than 1.5% for both substances.
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Determination of hypericin and Pseudohypericin by thin-layer chromatography—densitometry
Journal of Chromatography A, 1992Co-Authors: Th. Kartnig, I. Go¨belAbstract:Abstract The accuracy and reproducibility of the determination of hypericin and Pseudohypericin by measuring the emitted fluorescence in situ on thin-layer chromatography plates can be improved significantly by using appropriate dipping reagents. The effects of pyridine, polyethylene glycol 4000, paraffins, silicone oil and Triton X-100 in various solvents and combinations on the intensity and stability of emitted fluorescence are described. Using the test conditions established by this investigation, hypericin can be quantified exactly within the range 5–50 ng and Pseudohypericin within the range 20–200 ng. The relative standard deviation for the quantification under the given conditions is less than 1.5% for both substances.
Liudas Ivanauskas - One of the best experts on this subject based on the ideXlab platform.
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Secondary metabolites of Hypericum confertum and their possible chemotaxonomic significance.
Natural product communications, 2010Co-Authors: Cuneyt Cirak, Jolita Radusiene, Valdimaras Janulis, Liudas IvanauskasAbstract:The phloroglucinol derivative hyperforin, the naphthodianthrones hypericin and Pseudohypericin, the phenylpropane chlorogenic acid, and the flavonoids rutin, hyperoside, apigenin-7-O-glucoside, kaempferol, quercitrin, quercetin and amentoflavone were investigated in Hypericum confertum growing wild in Turkey. After drying at room temperature, the plant materials were assayed for secondary metabolite concentrations by HPLC. All the listed compounds were detected at various levels. This is the first report on the chemistry of H. confertum.
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The quantitative effects of temperature and light intensity on hyperforin and hypericins accumulation in Hypericum perforatum L
Journal of Medicinal Plants Research, 2009Co-Authors: Mehmet Serhat Odabas, Necdet Camas, J. Raduğienë, Valdimaras Janulis, Liudas Ivanauskas, Cuneyt CirakAbstract:The quantitative effects of temperature and light intensity on accumulations of hyperforin, hypericin and Pseudohypericin were examined in greenhouse-grownHypericum perforatum L. plants. Polyethylene cover of 50% transparency was used for shading. Temperature values and light intensities were measured daily in both shaded and un-shaded parts during experiment. Plants were harvested weekly and assayed for the chemical concentrations by HPLC after being dried at room temperature. Multi regression analyses were performed to describe the quantitative effects of temperature and light intensity on accumulation of phytochemicals. According to the results, increases in temperatures from 24 - 32°C and light intensities from 803.4 - 1618.6 µmolm-2s-1 resulted in a continuous increase in hyperforin, hypericin and Pseudohypericin contents. The relationships between temperatures & light intensity and accumulation of phytochemicals were formulized as PC = [a + (b1 x t) + (b2 x l) + (b3 x l²) + (b4 x (t x l))] where PC – phytochemicals, t–temperature (°C), l–light intensity (µmolm-2s-1), and a, b1, b2, b3 and b4–coefficients of the produced equations. R2? Values were 0.80 for hyperforin, 0.93 for hypericin and 0.96 for Pseudohypericin. All R2 values and standard errors of the equations were found to be significant at the p < 0.001 level. Key words: Hypericum perforatum, hyperforin, hypericin, Pseudohypericin, light, temperature, modeling.
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Variation of Bioactive Secondary Metabolites in Hypericum triquetrifolium Turra from Wild Populations of Turkey
Natural Product Communications, 2008Co-Authors: Necdet Camas, Cuneyt Cirak, Jolita Radušienė, Ali Kemal Ayan, Valdimaras Janulis, Liudas IvanauskasAbstract:The present study was conducted to determine the variation in the content of hyperforin, hypericin and Pseudohypericin in Hypericum triquetrifolium Turra growing wild in four locations of Turkey. The aerial parts, representing a total of 30 individuals, were collected at full flowering and dissected into floral, leaf and stem tissues. After drying at room temperature, the plant materials were assayed for their chemical contents by HPLC. The populations varied significantly in chemical contents. Hyperforin content ranged from 0.05 to 0.56 mg/g, hypericin from 0.74–1.98 mg/g, and Pseudohypericin from 0.72–2.26 mg/g, dry weight. Among the different plant parts, the flowers were found to be the principle organ for hyperforin accumulation, while hypericin and Pseudohypericin were accumulated mainly in leaves. Such kinds of data could be useful for optimizing the processing methodology of wild-harvested plant material and phytochemical evaluation of H. triquetrifolium.
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Pseudohypericin and Hyperforin in Hypericum perforatum from Northern Turkey: Variation among Populations, Plant Parts and Phenological Stages
Journal of integrative plant biology, 2008Co-Authors: Cuneyt Cirak, Jolita Radusiene, Valdimaras Janulis, Liudas IvanauskasAbstract:Hypericum perforatum is a perennial medicinal plant known as "St. John's wort" in Western Europe and has been used in the treatment of several diseases for centuries. In the present study, morphologic, phenologic and population variability in Pseudohypericin and hyperforin concentrations among H. perforatum populations from Northern Turkey was investigated for the first time. The aerial parts of H. perforatum plants representing a total of 30 individuals were collected at full flowering from 10 sites of Northern Turkey to search the regional variation in the secondary metabolite concentrations. For morphologic and phenologic sampling, plants from one site were gathered in five phenological stages: vegetative, floral budding, full flowering, fresh fruiting and mature fruiting. The plant materials were air-dried at room temperature and subsequently assayed for chemical concentrations by high performance liquid chromatography. Secondary metabolite concentrations ranged from traces to 2.94mg/g dry weight (DW) for Pseudohypericin and traces -6.29mg/g DW for hyperforin. The differences in the secondary metabolite concentrations among populations of H. perforatum were found to be significant. The populations varied greatly in hyperforin concentrations, whereas they produced a similar amount of Pseudohypericin. Concentrations of both secondary metabolites in all tissues increased with advancing of plant development and higher accumulation levels were reached at flowering. Among different tissues, full opened flowers were found to be superior to stems, leaves and the other reproductive parts with regard to Pseudohypericin and hyperforin accumulations. The present findings might be useful to optimize the processing methodology of wild-harvested plant material and obtain increased concentrations of these secondary metabolites.
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Chemical Constituents of SomeHypericum Species Growing in Turkey
Journal of Plant Biology, 2007Co-Authors: Cüneyt Çlrak, Jolita Radusiene, Valdimaras Janulis, Liudas Ivanauskas, Burhan ArslanAbstract:The present study was conducted to determine the content of pharmacologically important constituents hypericin, Pseudohypericin, chlorogenic acid, rutin, hyperoside, apigenin-7-O-glucoside, quercitrin, quercetin and vitexin in eight Hypericum species namely, H. aviculariifolium Jaup. and Spach subsp. depilatum (Freyn and Bornm.) Robson var. depilatum (endemic), H. lydium Boiss., H. montbretii Spach, H. orientale L, H. origanifolium Willd, H. perfoliatum L, H. perforatum L. and H. pruinatum Boiss. and Bal. growing in different locations of Turkey. Wild growing plants were harvested at flowering and after dried subsequently assayed for the constituents by HPLC method. Hyperoside, quercitrin and Pseudohypericin were found in all species. Hypericin, quercetin and chlorogenic acid were also detected in all species with the exceptions of H. orientale for hypericin, H. montbretii for quercetin and H. lydium for chlorogenic acid. Apigenin-7-O-glucoside accumulation was observed in all examined species at various levels, except for H. orientale and H. origanifolium. Rutin was detected in H. aviculariifolium , H. lydium, H. orientale, H. perfoliatum and H. perforatum. On the contrary of the other species, vitexin was found in only H. motbretii. The presence of flavonoid vitexin in the genus Hypericum was reported for the first time.
Shizuo Yamada - One of the best experts on this subject based on the ideXlab platform.
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In vitro photochemical and phototoxicological characterization of major constituents in St. John's Wort (Hypericum perforatum) extracts.
Phytochemistry, 2011Co-Authors: Satomi Onoue, Yoshiki Seto, Masanori Ochi, Ryo Inoue, Hideyuki Ito, Tsutomu Hatano, Shizuo YamadaAbstract:Extracts from St. John's Wort (SJW: Hypericum perforatum) have been used for the treatment of mild-to-moderate depression. In spite of the high therapeutic potential, orally administered SJW sometimes causes phototoxic skin responses. As such, the present study aimed to clarify the phototoxic mechanisms and to identify the major phototoxins of SJW extract. Photobiochemical properties of SJW extract and 19 known constituents were characterized with focus on generation of reactive oxygen species (ROS), lipid peroxidation, and DNA photocleavage, which are indicative of photosensitive, photoirritant, and photogenotoxic potentials, respectively. ROS assay revealed the photoreactivity of SJW extract and some SJW ingredients as evidenced by type I and/or II photochemical reactions under light exposure. Not all the ROS-generating constituents caused photosensitized peroxidation of linoleic acid and photodynamic cleavage of plasmid DNA, and only hypericin, Pseudohypericin, and hyperforin exhibited in vitro photoirritant potential. Concomitant UV exposure of quercitrin, an SJW component with potent UV/Vis absorption, with hyperforin resulted in significant attenuation of photodynamic generation of singlet oxygen from hyperforin, but not with hypericin. In conclusion, our results suggested that hypericin, Pseudohypericin, and hyperforin might be responsible for the in vitro phototoxic effects of SJW extract.
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In vitro photochemical and phototoxicological characterization of major constituents in St. John’s Wort (Hypericum perforatum) extracts
Phytochemistry, 2011Co-Authors: Satomi Onoue, Yoshiki Seto, Masanori Ochi, Ryo Inoue, Hideyuki Ito, Tsutomu Hatano, Shizuo YamadaAbstract:Extracts from St. John’s Wort (SJW: Hypericum perforatum) have been used for the treatment of mild-to-moderate depression. In spite of the high therapeutic potential, orally administered SJW sometimes causes phototoxic skin responses. As such, the present study aimed to clarify the phototoxic mechanisms and to identify the major phototoxins of SJW extract. Photobiochemical properties of SJW extract and 19 known constituents were characterized with focus on generation of reactive oxygen species (ROS), lipid peroxidation, and DNA photocleavage, which are indicative of photosensitive, photoirritant, and photogenotoxic potentials, respectively. ROS assay revealed the photoreactivity of SJW extract and some SJW ingredients as evidenced by type I and/or II photochemical reactions under light exposure. Not all the ROS-generating constituents caused photosensitized peroxidation of linoleic acid and photodynamic cleavage of plasmid DNA, and only hypericin, Pseudohypericin, and hyperforin exhibited in vitro photoirritant potential. Concomitant UV exposure of quercitrin, an SJW component with potent UV/Vis absorption, with hyperforin resulted in significant attenuation of photodynamic generation of singlet oxygen from hyperforin, but not with hypericin. In conclusion, our results suggested that hypericin, Pseudohypericin, and hyperforin might be responsible for the in vitro phototoxic effects of SJW extract.
Donna M. Gibson - One of the best experts on this subject based on the ideXlab platform.
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The production of hypericins in two selected Hypericum perforatum shoot cultures is related to differences in black gland structure.
Plant physiology and biochemistry : PPB, 2006Co-Authors: Ari Kornfeld, Donna M. Gibson, Peter B. Kaufman, Steven F. Bolling, Sara L. Warber, Soo Chul Chang, Ara KirakosyanAbstract:In vitro shoot cultures of Hypericum perforatum derived from wild populations grown in Armenia have a wide variation of hypericin and Pseudohypericin metabolite content. We found that a germ line denoted as HP3 produces six times more hypericin and fourteen times more Pseudohypericin than a second line labeled HP1. We undertook a structural comparison of the two lines (HP1 and HP3) in order to see if there are any anatomical or morphological differences that could explain the differences in production of these economically important metabolites. Analysis by LM (light microscopy), SEM (scanning electron microscopy), and TEM (transmission electron microscopy) reveals that the hypericin/Pseudohypericin-containing black glands located along the margins of the leaves consist of a peripheral sheath of flattened cells surrounding a core of interior cells that are typically dead at maturity. The peripheral cells of the HP3 glands appear less flattened than those of the HP1 glands. This may indicate that the peripheral cells are involved in hypericin/Pseudohypericin production. Furthermore, we find that these peripheral cells undergo a developmental transition into the gland's interior cells. The fact that the size of the peripheral cells may correlate with metabolite production adds a new hypothesis for the actual site of hypericin synthesis.
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Variation in Hypericins from wild populations ofHypericum perforatum L. in the Pacific Northwest of the U.S.A.
Economic Botany, 2002Co-Authors: Tara M. Sirvent, Loren Walker, Nan Vance, Donna M. GibsonAbstract:Representatives from eight wild populations of Hypericum perforatum L. were collected from Montana and Northern California at flowering, and subsequently analyzed for hypericin and Pseudohypericin using HPLC analysis. Total individual plant concentrations in these wild populations were from 0.0003–0.1250% dry weight (DW) hypericin and 0.0019–0.8458% DW Pseudohypericin. In general, hypericin concentrations were highest in the plant’s reproductive (flower and bud) tissues, followed by leaf and stem tissues, respectively. Hypericin and Pseudohypericin concentrations were positively correlated in all samples, although the relative ratio of hypericin to Pseudohypericin varied with site location. Los representantes a partir de ocho poblaciones silvestres del Hypericum perforatum L. fueron recogidos de Montana y de California norteña en el florecimiento, y analizados posteriormente para el hypericin y el Pseudohypericin usando análisis del HPLC. Las concentraciones totales de la planta individual en estas poblaciones silvestres eran a partir de 0,0003–0,1250% peso seco hypericin y 0,0019–0,8458% peso seco Pseudohypericin. En general, las concentraciones del hypericin eran las más altas de los tejidos reproductivos de la planta (flor y capullos), seguidos por la hoja y los tejidos del tallo, respectivamente. Las concentraciones de Hypericin y del Pseudohypericin fueron correlacionadas positivamente en todas las muestras, aunque la relación relativa del hypericin al Pseudohypericin varió con la localización de sitio.
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Variation in Hypericins from wild populations ofHypericum perforatum L. in the Pacific Northwest of the U.S.A.
Economic Botany, 2002Co-Authors: Tara M. Sirvent, Loren Walker, Nan Vance, Donna M. GibsonAbstract:Representatives from eight wild populations of Hypericum perforatum L. were collected from Montana and Northern California at flowering, and subsequently analyzed for hypericin and Pseudohypericin using HPLC analysis. Total individual plant concentrations in these wild populations were from 0.0003–0.1250% dry weight (DW) hypericin and 0.0019–0.8458% DW Pseudohypericin. In general, hypericin concentrations were highest in the plant’s reproductive (flower and bud) tissues, followed by leaf and stem tissues, respectively. Hypericin and Pseudohypericin concentrations were positively correlated in all samples, although the relative ratio of hypericin to Pseudohypericin varied with site location. Los representantes a partir de ocho poblaciones silvestres del Hypericum perforatum L. fueron recogidos de Montana y de California norteña en el florecimiento, y analizados posteriormente para el hypericin y el Pseudohypericin usando análisis del HPLC. Las concentraciones totales de la planta individual en estas poblaciones silvestres eran a partir de 0,0003–0,1250% peso seco hypericin y 0,0019–0,8458% peso seco Pseudohypericin. En general, las concentraciones del hypericin eran las más altas de los tejidos reproductivos de la planta (flor y capullos), seguidos por la hoja y los tejidos del tallo, respectivamente. Las concentraciones de Hypericin y del Pseudohypericin fueron correlacionadas positivamente en todas las muestras, aunque la relación relativa del hypericin al Pseudohypericin varió con la localización de sitio.
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variation in hypericins from wild populations of hypericum perforatum l in the pacific northwest of the u s a
Economic Botany, 2002Co-Authors: Tara M. Sirvent, Loren Walker, Nan Vance, Donna M. GibsonAbstract:Abstract Representatives from eight wild populations of Hypericum perforatum L. were collected from Montana and Northern California at flowering, and subsequently analyzed for hypericin and Pseudohypericin using HPLC analysis. Total individual plant concentrations in these wild populations were from 0.0003–0.1250% dry weight (DW) hypericin and 0.0019–0.8458% DW Pseudohypericin. In general, hypericin concentrations were highest in the plant’s reproductive (flower and bud) tissues, followed by leaf and stem tissues, respectively. Hypericin and Pseudohypericin concentrations were positively correlated in all samples, although the relative ratio of hypericin to Pseudohypericin varied with site location.
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Regional differences in hypericin and Pseudohypericin concentrations and five morphological traits among Hypericum perforatum plants in the northwestern United States
Canadian Journal of Botany, 2001Co-Authors: Loren Walker, Donna M. Gibson, Tara Sirvent, Nan VanceAbstract:Geographic differences among Hypericum perforatum L. plants in concentration of two hypericins and five morphological characteristics were analyzed in plants collected from four sites each in northern California and western Montana and two sites in Oregon. Differences among regional collections of H. perforatum were assessed based on analysis of hypericin and Pseudohypericin concentration in floral, leaf, and stem tissue; light and dark leaf gland density; leaf area; leaf length/width ratio; and stem height. Significant differences in morphological and biochemical traits were detected primarily between samples collected from California and Montana. California samples had higher concentrations of hypericins, greater leaf gland density, larger leaves, and taller stems than those from Montana. Overall, Oregon samples did not consistently differentiate from those of Montana and California. Seasonal differences in hypericins were analyzed in Oregon plants only. Mean floral concentration of Pseudohypericin (0.2...
