St John's Wort Research Today is a free monthly online journal that collates and summarizes the latest research about St John's Wort, including details on depression, anxiety, side-effects, dosage, benefits. | ||||||
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Root cultures of Hypericum perforatum subsp. angustifolium elicited with chitosan and production of xanthone-rich extracts with antifungal activity.Tocci N, Simonetti G, D'Auria FD, Panella S, Palamara AT, Valletta A, Pasqua G Department of Environmental Biology, "Sapienza" University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy. Hypericum perforatum is a well-known medicinal plant which contains a wide variety of metabolites, including xanthones, which have a wide range of biological properties, including antifungal activity. In the present study, we evaluated the capability of roots regenerated from calli of H. perforatum subsp. angustifolium to produce xanthones. Root biomass was positively correlated with the indole-3-butyric acid concentration, whereas a concentration of 1 mg l(-1) was the most suitable for the development of roots. High auxin concentrations also inhibited xanthone accumulation. Xanthones were produced in large amounts, with a very stable trend throughout the culture period. When the roots were treated with chitosan, the xanthone content dramatically increased, peaking after 7 days. Chitosan also induced a release of these metabolites into the culture. The maximum accumulation (14.26 ± 0.62 mg g(-1) dry weight [DW]) and release (2.64 ± 0.13 mg g(-1) DW) of xanthones were recorded 7 days after treatment. The most represented xanthones were isolated, purified, and spectroscopically characterized. Antifungal activity of the total root extracts was tested against a broad panel of human fungal pathogen strains (30 Candida species, 12 Cryptococcus neoformans, and 16 dermatophytes); this activity significantly increased when using chitosan. Extracts obtained after 7 days of chitosan treatment showed high antifungal activity (mean minimum inhibitory concentration of 83.4, 39.1, and 114 μg ml(-1) against Candida spp., C. neoformans, and dermatophytes, respectively). Our results suggest that root cultures can be considered as a potential tool for large-scale production of extracts with stable quantities of xanthones. Published 6 May 2011 in Appl Microbiol Biotechnol. Articles on St John's Wort published 29 April 2011: Analysis of secondary plant metabolites by indirect desorption electrospray ionization imaging mass spectrometry. Anal Chem, 83(9): 3256-9. Secondary metabolites in plant material can be imaged in a simple and robust way by creating an imprint of the plant material on a porous Teflon surface. The Teflon surface serves to extract compounds from the plant material for enhanced desorption electrospray ionization imaging analysis, while maintaining the spatial information of the sample. The method, which remedies for limitations in mass spectrometry imaging of compounds embedded in plant material, was demonstrated on leaves and petals ... [Abstract] [Full-text] Articles on St John's Wort published 26 April 2011: Effects of UV-B on Secondary Metabolites of St. John's Wort (Hypericum perforatum L.) Grown in Controlled Environments. Photochem Photobiol, 87(3): 680-4. The medicinal plant industry is under increasing scrutiny due to wide variance in active ingredient (AI) concentration from values claimed on labels. Reasons for this disparity include environmental and genotypic variation which influence AI concentration. St. John's wort (Hypericum perforatum) is a popular herbal remedy which also exhibits marked variance in AI concentration among products. This study evaluated concentration changes of three biologically active metabolites of H. perforatum ... [Abstract] [Full-text] Articles on St John's Wort published 25 April 2011: St. John's Wort (Hypericum perforatum L.) is a useful medication in the treatment of mild to moderate depression. By reanalysis of the data obtained from a total of 154 patients, who responded in a randomised, multicentric, double-blind, placebo-controlled study, to 6 weeks of treatment for an episode of moderate depression with either 20mg citalopram or 900mg Hypericum extract STW 3-VI, the duration of response and occurrence of relapse/recurrence were evaluated. Duration of response and ... [Abstract] [Full-text] Induction of apoptosis in K562 cells by dicyclohexylammonium salt of hyperforin through a mitochondrial-related pathway. Chem Biol Interact, 190(2): 91-101. Hyperforin is an abundant phloroglucinol-type constituent isolated from the extract of the flowering upper portion of the plant Hypericum perforatum L. The dicyclohexylammonium salt of hyperforin (DCHA-HF) has exhibited antitumor and antiangiogenic activities in various cancer cells. Here, the antitumor effects of DCHA-HF on the chronic myeloid leukemia K562 cell line were investigated for the first time. DCHA-HF exhibited dose- and time-dependent inhibitory activities against K562 cells, with ... [Abstract] [Full-text] St. John's Wort (Hypericum perforatum L.) is a useful medication in the treatment of mild to moderate depression. By reanalysis of the data obtained from a total of 154 patients, who responded in a randomised, multicentric, double-blind, placebo-controlled study, to 6 weeks of treatment for an episode of moderate depression with either 20mg citalopram or 900mg Hypericum extract STW 3-VI, the duration of response and occurrence of relapse/recurrence were evaluated. Duration of response and ... [Abstract] [Full-text] Induction of apoptosis in K562 cells by dicyclohexylammonium salt of hyperforin through a mitochondrial-related pathway. Chem Biol Interact, 190(2): 91-101. Hyperforin is an abundant phloroglucinol-type constituent isolated from the extract of the flowering upper portion of the plant Hypericum perforatum L. The dicyclohexylammonium salt of hyperforin (DCHA-HF) has exhibited antitumor and antiangiogenic activities in various cancer cells. Here, the antitumor effects of DCHA-HF on the chronic myeloid leukemia K562 cell line were investigated for the first time. DCHA-HF exhibited dose- and time-dependent inhibitory activities against K562 cells, with ... [Abstract] [Full-text] Articles on St John's Wort published 13 April 2011: Secondary metabolites in plant material can be imaged in a simple and robust way by creating an imprint of the plant material on a porous Teflon surface. The Teflon surface serves to extract compounds from the plant material for enhanced desorption electrospray ionization imaging analysis, while maintaining the spatial information of the sample. The method, which remedies for limitations in mass spectrometry imaging of compounds embedded in plant material, was demonstrated on leaves and petals ... [Abstract] [Full-text] Articles on St John's Wort published 8 April 2011: Secondary metabolites in plant material can be imaged in a simple and robust way by creating an imprint of the plant material on a porous Teflon surface. The Teflon surface serves to extract compounds from the plant material for enhanced Desorption Electrospray Ionization imaging analysis, while maintaining the spatial information of the sample. The method, which remedies for limitations in mass spectrometry imaging of compounds embedded in plant material, was demonstrated on leaves and petals ... [Abstract] [Full-text] © 2004-2011 St John's Wort Research Today. All Rights Reserved. |
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