In situ imaging of usnic acid in selected Cladonia spp. by vibrational spectroscopy

Liao, Catherine R.; Piercey‐Normore, Michele D.; Sorensen, John L.; Gough, Kathleen

doi:10.1039/c0an00533a

Cited by 31 publications

(27 citation statements)

References 30 publications

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“…Very recently, FPA-FTIR imaging and Raman microscopy were used to localize the presence of usnic acid in Cladonia arbuscula, C. uncialis and C. sulphurina (Liao et al 2010). The techniques can provide time-resolved information about the distribution of major compounds in lichens.…”

Section: In Vivo Imagingmentioning

confidence: 99%

Advanced methods for the study of the chemistry and the metabolism of lichens

2011

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Lichens are compound entities of a fungal partner (''mycobiont'') and one or more photosynthetically active algae or cyanobacteria (''photobionts''). The organisms live in an intimate, symbiotic association which has been classified as a mutualistic or controlled parasitic relationship. Several metabolites from lichens display unique structures with unknown functions, and only a few model species have been analysed comprehensively. The complex metabolic interplay between the organisms in lichens is also incompletely understood. Earlier experiments with 14 C-labelled precursors indicated that the photobionts produce from CO 2 glucose or sugar alcohols (e.g. ribitol and arabitol) which are then transferred to the mycobionts. In the fungi, these compounds are believed to be converted into mannitol serving as the carbon and energy source in the downstream metabolic processes. Recent methodological developments in spectroscopy and ''systems biology'' now enable a concise analysis of the metabolite profiles, networks and fluxes by non-targeted quantitative approaches. In this review, we summarize the current knowledge about lichen metabolism and report on the potential of the advanced methods to reinvestigate lichen chemistry and metabolism on a quantitative basis.

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Section: In Vivo Imagingmentioning

confidence: 99%

Advanced methods for the study of the chemistry and the metabolism of lichens

2011

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“…These three LSM commonly occur in saxicolous lichens, in both silicicolous and calcicolous species (Smith et al, 2009). Usnic acid is a yellowish dibenzofuran, exclusive to lichen-forming fungi and widely distributed in the vegetative and reproductive structures of several species (e.g., species of genera Lecanora, Ramalina) ( Ingólfsdóttir, 2002;Liao et al, 2010). It is well known for antibacterial and antifungal properties (and for antiprotozoal, antiviral, antiproliferative, antiinflammatory, analgesic, antipyretic, antitumor activities) which have been mostly studied for potential therapeutic applications ( Cocchietto et al, 2002;Ingólfsdóttir, 2002), and is also known to play UV protection of thalli ( McEvoy et al, 2006).…”

Section: Introductionmentioning

confidence: 99%

Biocidal effect of lichen secondary metabolites against rock-dwelling microcolonial fungi, cyanobacteria and green algae

Gazzano

Favero‐Longo

Iacomussi

et al. 2013

International Biodeterioration & Biodegradation

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The use of commercial biocides in outdoor environments is increasingly discouraged because of their ecotoxicity, new methods being thus invoked to control patinas of biological origin on the stone cultural heritage. The effects of secondary metabolites (usnic acid, norstictic acid, parietin) produced by saxicolous lichens, natural competitors of rock dwelling microorganisms, were investigated invitro against microcolonial fungi (MCF: Coniosporium apollinis, Coniosporium perforans, Coniosporium uncinatum, Phaeococcomyces-like sp.), coccoid cyanobacteria (Chroococcus minutus) and green algae (Scenedesmus ecornis) which commonly occur on stonework. An acetone/water 10/90 vol/vol mixture was screened as suitable to solubilise the lichen metabolites and to not affect the bioassay results. Benzalkonium chloride 1% was used as positive control.All the three metabolites (approx. 10-2mM) inhibited the growth of the assayed MCF species, displaying the same effect of benzalkonium chloride. Chroococcus and Scenedesmus exhibited sensibility to the lichen metabolites when exposed to high incubation temperatures (35°C), chemicals and temperature synergically yielding percentage decreases of intact cells with red chlorophyll epifluorescence. These findings suggest lichen secondary metabolites as allelopathic agents against rock dwelling microorganisms and as potential natural sources for their control on stone materials in restoration and conservation programmes. In this perspective, the detection of a negligible chromatic alteration (δE<0.5) caused by LSM to the white Carrara marble is reported as the first step of the necessary extensive evaluation of the LSM-stone material interactions

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“…More recently, Raman spectroscopy and FPA-FTIR were used to image the distribution of usnic acid within Cladonia arbsucula, C. sulphurina, and C. uncialis (Liao et al 2010). This dibenzofuran-related metabolite was shown to be present in pycnidia and younger branches of C. arbuscula and C. uncialis, in C. sulphurina's soredia as well as in the spore-forming region of C. uncialis' apothecia.…”

Section: Raman and Ftir Spectroscopymentioning

confidence: 99%