The antifungal and Cryptococcus neoformans virulence attenuating activity of Pelargonium sidoides extracts.
Abstract Ethnopharmacological relevance Limitations of clinical antifungal treatments and drug-resistance are drivers of the search for novel antifungal strategies. Extracts prepared from the tubers of the medicinal plant, Pelargonium sidoides , are known for their antiviral and antibacterial activi...
| Publicado en: | Journal of Ethnopharmacology Vol. 235; pp. 122 - 133 |
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| Autores principales: | , , , , |
| Formato: | research tables/charts Journal Article |
| Publicado: |
Elsevier B.V.
May2019
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=135255903&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 135255903 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 03788741 3MS jtl: Journal of Ethnopharmacology issn: 03788741 maglogo: N pubinfo: dt: May2019 vid: 235 pid: 1004 pub: Elsevier B.V. artinfo: ui: 135255903 135255903 135255903 10.1016/j.jep.2019.02.008 135255903 ppf: 122 ppct: 11 formats: tig: atl: The antifungal and Cryptococcus neoformans virulence attenuating activity of Pelargonium sidoides extracts. aug: au: Samie, Shakier Trollope, Kim M. Joubert, Lydia-Marié Makunga, Nokwanda P. Volschenk, Heinrich affil: Department of Microbiology, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa sug: subj: Cryptococcus Drug Effects Virulence Drug Effects Plants, Medicinal Pharmacodynamics Plant Extracts Pharmacodynamics Signal Transduction Drug Effects Human Ethanol Platelet Count Yeasts Hemolysis Organic Chemicals Guided Imagery Chromatography Biological Assay Polysaccharides Steroids Urease Drug Effects Microscopy, Electron Oxidoreductases Drug Effects Capsules Medicine, Traditional ab: Abstract Ethnopharmacological relevance Limitations of clinical antifungal treatments and drug-resistance are drivers of the search for novel antifungal strategies. Extracts prepared from the tubers of the medicinal plant, Pelargonium sidoides , are known for their antiviral and antibacterial activities and are used in ethnomedicine for the treatment of acute respiratory infections. Their impact on fungi has not been well characterised. Here, we provide a first report on the antifungal activity of a P. sidoides aerial tissue extract against Cryptococcus neoformans as well as the effects of both tuber and aerial tissue extracts on selected virulence factors. Aim of the study Novel antimicrobial strategies that target multiple cellular pathways or make use of anti-pathogenic compounds that inhibit virulence factors have been proposed. This work aimed to evaluate P. sidoides plant parts for their anticryptococcal activity and antipathogenic properties on selected virulence factors. Materials and methods The antifungal activity of crude P. sidoides tuber and aerial tissue extracts (15% m/m ethanol) were compared using a modified colourimetric antifungal susceptibility test. Fungicidal activity of the extracts was confirmed by plate counts. To test yeast resistance to the extracts, it was conditioned by multiple passages in sub-lethal doses followed by antifungal susceptibility testing. Cytotoxicity of the extracts was tested with a blood agar haemolysis assay. Extracts were evaluated for the presence of multiple bioactive compounds by solid-phase fractionation and visualisation by thin-layer chromatography in combination with bioassays. The influence of extracts on the production of the polysaccharide capsule, ergosterol content as well as laccase and urease activities were also evaluated. Cell surface variations after extract exposure were visualised by scanning electron microscopy (SEM). Results Both tuber and aerial tissue extracts were fungicidal and contained multiple bioactive compounds which constrained the development of antifungal resistance. No haemolytic activity was observed, and the extracts did not appear to target ergosterol biosynthesis. However, the extracts displayed anti-pathogenic potential by significantly inhibiting laccase and urease activity while also significantly reducing capsule size. SEM revealed notable cell surface variations and provided support for the observed reduction in capsule size. Conclusions Our results provide support to the exploration of medicinal plants as sources of alternative antifungal therapies and the potential use of multicomponent inhibition and or virulence attenuation for next-generation treatment strategies. Our data also provide relevant information that may support the further use of P. sidoides in traditional medicines as well as in commercialised phytopharmaceuticals. Graphical abstract fx1 pubtype: Academic Journal doctype: research tables/charts Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
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