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Xanthones produced from plant roots and from chitosan-treated cell cultures and in vitro regenerated roots of Hypericum perforatum subsp. angustifolium
No full textEstratti di colture altamente standardizzate di Hypericum perforatum subsp. angustifolium ad alta potenzialità antifungina
No full textEffetto del chitosano sulla biosintesi di xantoni e flavonoidi in colture cellulari di Hypericum perforatum subsp. angustifolium
No full textProduzione di xantoni da radici avventizie di Hypericum perforatum subsp. angustifolium ed attività antifungina
No full textHypericum 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. 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
In vitro antifungal activity of extracts obtained from Hypericum perforatum adventitious roots cultured in a mist bioreactor against planktonic cells and biofilm of Malassezia furfur
No full textExtracts of Hypericum perforatum roots grown in a bioreactor showed activity against planktonic cells and biofilm of Malassezia furfur. Dried biomass, obtained from roots grown under controlled conditions in a ROOTec mist bioreactor, has been extracted with solvents of increasing polarity (i.e. chloroform, ethyl acetate and methanol). The methanolic fraction was the richest in xanthones (2.86 ± 0.43 mg g− 1 DW) as revealed by HPLC. The minimal inhibitory concentration of the methanol extract against M. furfur planktonic cells was 16 μg mL− 1. The inhibition percentage of biofilm formation, at a concentration of 16 μg mL− 1, ranged from 14% to 39%. The results show that H. perforatum root extracts could be used as new antifungal agents in the treatment of Malassezia infections
Colture di radici di Hypericum perforatum subsp. angustifolium, per la produzione di estratti ad attività antifungina
No full textA three-step culture system to increase the xanthone production and antifungal activity of Hypericum perforatum subsp. angustifolium in vitro roots
No full textHypericum perforatum is a well-known medicinal plant. Among all secondary metabolites produced by this species, xanthones are very interesting for their antifungal activity. In the present study, with the aim to improve xanthone production and antifungal activity of H. perforatum subsp. angustifolium (sin. Frohlich) Borkh in vitro roots, a new methodology consisting of a three-step culture system, has been developed. Regenerated roots of H. perforatum were cultured in a three-step culture system: in the first step, to increase biomass, the roots were cultured in half-strength liquid Murashige and Skoog (MS) medium supplemented with 1 mg L-1 indole butyric acid (IBA) and 1.5% sucrose. In the second and third steps, to stimulate secondary metabolism, the roots were cultured with 1.1 mg L-1 2,4-dichlorophenoxyacetic acid (2,4-D), 0.215 mg L-1 kinetin (KIN), and 0.186 mg L-1 1-naphthalenacetic acid (NAA). In the third step, some of the roots were treated with chitosan. Xanthone production increased 2.7 times following the three-step method. The mean minimal inhibitory concentration (MIC) values were of 36.9, 26.7, and 65 mu g mL(-1), against Candida species, Cryptococcus neoformans and dermatophytes, respectively. A positive correlation between xanthone accumulation and antifungal activity has been shown
Chemical composition and antifungal activity of Hypericum perforatum subsp. angustifolium roots from wild plants and plants grown under controlled conditions
No full textThe medicinal properties of the aerial parts of Hypericum perforatum subsp. angustifolium have been extensively investigated, yet little is known about the chemical composition or potential uses of the root extracts. In this study, xanthone production in wild plants and plants grown under controlled conditions was investigated. Chemical analyses carried out on wild plants revealed that xanthones were mainly accumulated in the roots. We mainly detected 1,7-dihydroxyxanthone, paxanthone, 5-O-methyl-2-deprenylrheediaxanthone B, kielcorin. The roots of wild plants showed low xanthone accumulation. In the roots of plants grown under controlled conditions, xanthone accumulation was 27 times greater than that in the roots of wild-grown plants. Kielcorin was not detected in the roots of plants grown under controlled conditions. As xanthones are known for their antifungal activity, the extracts from both samples were tested against the human fungal pathogens Candida albicans, non-albicansCandida species, Cryptococcus neoformans, and dermatophytes. The root extracts from plants grown under controlled conditions showed greater antifungal activity, probably correlated with higher xanthone accumulation
Radici in vitro di Hypericum perforatum subsp. angustifolium come modello per lo studio della via biosintetica degli xantoni
No full textChitosan enhances xanthone production in Hypericum perforatum subsp. angustifolium cell cultures
No full textHypericum perforatum is an important medicinal plant containing numerous biologically active compounds. The effect of chitosan elicitation on xanthone biosynthesis in calli and in cell suspension cultures of H. perforatum subsp. angustifolium was evaluated. Elicited cell cultures showed an increase in xanthone production and a simultaneous decrease in flavonoid production. Chitosan also induced the production of 1,7-dihydroxyxanthone (euxanthone) and cadensin G, which were not detected in either the calli nor the non-elicited cell cultures. 1,7-Dihydroxyxanthone was in part (21%) released in the culture medium
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