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Hyperforin is a major metabolite of the medicinal plant Hypericum perforatum (St. John's Wort) and has recently been found in hormone induced root cultures. The objective of this study is to identify a downstream process for the production of a hyperforin-rich extract with maximum extraction
Extracts of the herb St John's Wort have been shown to reduce alcohol intake in alcohol-preferring rats, but it is not known which of the constituent(s) are responsible for this effect. In this study, the effect of a crude methanolic extract of Hypericum perforatum (negligible hyperforin content) on
Cut sprouts of Hypericum perforatum were proffered solutions containing [1-(13)C]glucose or [U-(13)C(6)]glucose. Hyperforin was isolated and analyzed by quantitative NMR spectroscopy. The labeling patterns show that the biosynthesis of hyperforin involves five isoprenoid moieties, which are derived
An overview of the constituents of Hypericum perforatum is given, with special emphasis on the acylphloroglucinol hyperforin. Previous work on the chemistry of hyperforin and on other components derived from hyperforin in H. perforatum is reviewed. A new optimized method of isolating hyperforin on a
The isolation of two oxidation products of hyperforin from the aerial parts of Hypericum perforatum and their structure determination by means of 2D NMR methods is reported. The products had the same 1-(2-methyl-1-oxopropyl)-2,12-dioxo-3,10 beta-bis(3-methyl-2-butenyl)-11 beta-methyl-11
Repeated examination of the aerial parts of Hypericum perforatum yielded a new degradation product of hyperforin (1) namely deoxyfurohyperforin A (2), together with the previously identified furohyperforin (3), furoadhyperforin (4), furohyperforin A (5a and 5b), pyrano[7,28-b]hyperforin (6) and
Extracts of the medicinal plant Hypericum perforatum are used to treat depression and skin irritation. A major API is hyperforin, characterized by sensitivity to light, oxygen and temperature. Total synthesis of hyperforin is challenging and its content in field-grown plants is variable. We have
OBJECTIVE
Hypericum perforatum contains the therapeutically important compounds hypericin and hyperforin. Hypericin is known to accumulate in the dark glands. This investigation aimed to determine the accumulation site of hyperforin.
METHODS
Dark and translucent glands as well as non-secretory
Hyperforin is a pharmacologically active constituent of Hypericum perforatum (St. John's wort). In vitro cultures of this medicinal plant were found to contain hyperforin and three related polyprenylated acylphloroglucinol derivatives. The accumulation of these compounds was coupled to shoot
The effect of the pH of the mobile phase in HPLC analysis of hyperforin was investigated. Working with an extract of St. John's Wort (Hypericum perforatum L.) that is rich in hyperforin, significant differences were observed in conventional chromatograms depending on whether the mobile phase was
The separation of the lipophilic compounds in extracts of Hypericum perforatum L. is demonstrated in a non-aqueous capillary electrophoresis system with reversed electro-osmotic flow. Solvent mixtures of methanol, dimethylsulfoxide and N-methylformamide were used for the electrophoresis media, with
Samples of Hyperici herba were obtained by harvesting Hypericum perforatum L. in different plant development stages. The relation of flower development phases in the drug's flower fraction was examined. The HPLC method was then employed for the analysis of the content of secondary metabolites in
Renewed interest in plant-derived drugs has led to an increased need for efficient extraction methods. Hypericum perforatum L. contains several groups of bioactive compounds with noteworthy pharmacological activities. Direct sonication of H. perforatum was investigated and compared with conventional
St. John's Wort (Hypericum perforatum L.) was extracted with supercritical carbon dioxide using a pilot batch extraction plant. The effects of pressure, temperature, flow rate and extraction time were examined with respect to extraction yield and hyperforin content. Supercritical carbon dioxide
The present work describes isolation of bioactive lipophilic constituent [namely, hyperforin from St. John's wort (Hypericum perforatum L.)], of approximately 98% purity by semipreparative high-performance liquid chromatography (LC). The extraction, isolation, and analysis of the collected compound