Xanthones from roots, hairy roots and cell suspension cultures of selected Hypericum species and their antifungal activity against Candida albicans

Abstract

Highest xanthone contents were found in Hypericum pulchrum and H. annulatum untransformed roots. The best anti- Candida activity was obtained for hairy roots extracts of H. tetrapterum clone 2 ATCC 15834. Extracts of root cultures, hairy roots and cell suspensions of selected Hypericum spp. were screened for the presence of xanthones and tested for their antifungal activity against Candida albicans strain ATCC 10231. At least one of the following xanthones, 5-methoxy-2-deprenylrheediaxanthone; 1,3,6,7-tetrahydroxyxanthone; 1,3,5,6-tetrahydroxyxanthone; paxanthone; kielcorin or mangiferin was identified in methanolic extracts of the untransformed root cultures. The highest total xanthone content, with five xanthones, was found in untransformed H. pulchrum and H. annulatum root cultures. Hairy roots and the controls of H. tetrapterum contained 1,7-dihydroxyxanthone, while hairy root cultures and the corresponding controls of H. tomentosum contained toxyloxanthone B, 1,3,6,7- and 1,3,5,6-tetrahydroxyxanthone. Two xanthones, cadensin G and paxanthone, were identified in cell suspension cultures of H. perforatum. Their content increased about two-fold following elicitation with salicylic acid. The anti-Candida activity of the obtained extracts ranged from MIC 64 to >256 µg ml(-1). Among the extracts of Hypericum untransformed roots, the best antifungal activity was obtained for extracts of H. annulatum grown under CD conditions. Extracts of hairy roots clones A4 and 7 ATCC15834 of H. tomentosum and clone 2 ATCC15834 of H. tetrapterum displayed inhibition of 90% of Candida growth with 256 μg ml(-1). Extracts from chitosan-elicitated cells did not show antifungal activity.

Exodermis and endodermis are the sites of xanthone biosynthesis in Hypericum perforatum roots

“…Unlike hypericins, hyperforins, and flavonoids, which occur in the aerial parts of H. perforatum plants, xanthones are abundant in the roots, albeit their content fluctuates as a result of genetic variation and environmental factors (Crockett et al, 2011;Li et al, 2013;Tocci et al, 2013b;Zubrick a et al, 2015). In hairy roots, which result from Agrobacterium rhizogenes transformation, the xanthone concentration was increased compared with that in untransformed roots (Tusevski et al, 2013a).…”

Elicitation as a tool to improve the profiles of high-value secondary metabolites and pharmacological properties of Hypericum perforatum

“…Another study reported that JA treatment significantly increased phenolic compounds, flavanols and flavonols, concomitantly reducing the anthocyanin content . A twofold increase in the xanthone, cadensin G and paxanthone contents was found in cell suspension cultures of H. perforatum following elicitation with SA …”

“…[70] These authors also reported that treating H. perforatum shoot cultures with a S. maltophilia culture filtrate induced only pseudohypericin production. [70] Analysis of the methanolic extract of cell suspension cultures treated with A. tumefaciens revealed a 12-fold increase in the total xanthone concentration and the emergence of [41] Iron nano-oxide Hypericin and hyperforin [41] Chitin Phenolics, flavonols, flavanols, anthocyanins, hypericin and pseudohypericin [66] Pectin Phenolics, flavonols, flavanols, anthocyanins, hypericin and pseudohypericin [66] Dextran Phenolics, flavonols, flavanols, anthocyanins, hypericin and pseudohypericin [66] Phytophthora cinnamoni fungal cell wall extract None [39] Colletotrichum gloeosporioides mycelium extract Xanthones and flavonoids [35] Aspergillus flavus mycelium extract Phenolic compounds, flavanols, flavonols, anthocyanins and hypericins [62] Fusarium oxysporum Phenolics, flavonoids, anthocyanins, hypericin and pseudohypericin [63] Phoma exigua Phenolics, flavonoids, anthocyanins, hypericin and pseudohypericin [63] Botrytis cinerea Phenolics, flavonoids, anthocyanins, hypericin and pseudohypericin [63] JA Hypericins [39] JA Phenolic compounds, flavanols, flavonols, hypericin and pseudohypericin [38] MeJA Flavones [35] MeJA Flavonoids [8] SA Xanthones [85] SA None [35] SA None [39] SA Hypericins, pseudohypericins [86] SA Flavonoids [8] MeJA + C. gloeosporioides Xanthones [35] SA + C. gloeosporioides Xanthones [35] Agrobacterium tumefaciens Xanthones [71] A. tumefaciens Lignin and flavanoids [72] A. tumefaciens Phenolics, flavonols, flavanols and xanthones [73] A. rhizogenes Phenolics, flavonols, flavanols and xanthones [73] Callus SA Hypericins, pseudohypericins [86] Root MeJA Hypericin [84] IBA Hypericin [84] Acetic acid Xanthones…”

“…[38] A twofold increase in the xanthone, cadensin G and paxanthone contents was found in cell suspension cultures of H. perforatum following elicitation with SA. [85] Walker et al [39] found that JA dramatically enhanced hypericin production in cell cultures incubated in the dark compared to cultures grown under photoperiodic conditions, although SA treatment could not induce hypericin production in cell suspensions. Contrarily, SA remarkably influenced the production of hypericin and pseudohypericin in H. perforatum cell suspension cultures as per the report of Gadzovska-Simic et al [86] Abiotic elicitation…”

Atividade antioxidante, antimicrobiana e caracterização de compostos bioativos da casca interna de Kielmeyera coriacea Mart. & Zucc

“…Os resultados da atividade antifúngica frente às leveduras C. (SINGH et al, 2011;ZUBRICKÁ et al, 2015, MOKOKA et al, 2013MONTAGNER et al, 2008 A banda de absorbância em 230nm poderia ser atribuída aos flavonoides, já que os taninos condensados são formados por unidades de flavan-3-ol (uma classe de flavonoides).…”